''Croton lechleri'' is a species of
flowering plant
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...
in the
spurge
''Euphorbia'' is a very large and diverse genus of flowering plants, commonly called spurge, in the family Euphorbiaceae. "Euphorbia" is sometimes used in ordinary English to collectively refer to all members of Euphorbiaceae (in deference to t ...
family,
Euphorbiaceae
Euphorbiaceae, the spurge family, is a large family of flowering plants. In English, they are also commonly called euphorbias, which is also the name of a genus in the family. Most spurges, such as '' Euphorbia paralias'', are herbs, but some, ...
, that is native to northwestern
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sout ...
. It is commonly known as ''sangre de grado'' (Peruvian Spanish), ''sangre de drago'' (Ecuadorian Spanish) or ''sangre de grada'' (Bolivian Spanish), both of which translate to "
dragon's blood".
[Meza, E.N.(Editor). 1999.] They refer to this tree's (and several related species') thick red
latex
Latex is an emulsion (stable dispersion) of polymer microparticles in water. Latexes are found in nature, but synthetic latexes are common as well.
In nature, latex is found as a milky fluid found in 10% of all flowering plants (angiosperms ...
.
The latex has medicinal properties, and is used by local peoples as a
liquid bandage, applied to seal wounds, as it dries quickly to form a protective skin-like barrier.
Its use by native people has led to scientific study and observation of its ''
in vitro
''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called " test-tube experiments", these studies in biology ...
''
antioxidant activity as well as both
mutagenic
In genetics, a mutagen is a physical or chemical agent that permanently changes genetic material, usually DNA, in an organism and thus increases the frequency of mutations above the natural background level. As many mutations can cause cancer i ...
and
antimutagenic behavior.
The latex also contains a number of chemicals, including
taspine.
Oligomeric
proanthocyanidin
Proanthocyanidins are a class of polyphenols found in many plants, such as cranberry, blueberry, and grape seeds. Chemically, they are oligomeric flavonoids. Many are oligomers of catechin and epicatechin and their gallic acid esters. More compl ...
s, another kind of chemical contained in the latex, have been investigated for the treatment of
HIV
The human immunodeficiency viruses (HIV) are two species of ''Lentivirus'' (a subgroup of retrovirus) that infect humans. Over time, they cause acquired immunodeficiency syndrome (AIDS), a condition in which progressive failure of the immune ...
-associated diarrhea under the name
crofelemer
Crofelemer (USAN, trade name Mytesi) is an antidiarrheal indicated for the symptomatic relief of non-infectious diarrhea in adult patients with HIV/AIDS on antiretroviral therapy. Other possible uses include diarrhea in children, acute infectious ...
.
In January 2013, crofelemer, under the trade name Mytesi, was approved by the FDA for the treatment of non-infectious diarrhea in HIV+ patients.
Description
''Croton lechleri'' belongs to the family
Euphorbiaceae
Euphorbiaceae, the spurge family, is a large family of flowering plants. In English, they are also commonly called euphorbias, which is also the name of a genus in the family. Most spurges, such as '' Euphorbia paralias'', are herbs, but some, ...
and are medium sized trees with evergreen foliage, growing 10 to 20 meters (30 to 60 feet) in height.
Despite their relatively large height, the trees have very narrow trunks, averaging a bole diameter of about 30 centimeters (1 ft).
The leaves are large, alternate cordate (heart-shaped), bright green and 15–30 cm in width and length.
The flowers are greenish-white, white or amber, which produce small, three-part capsule fruits that appear on a thin spike that measures 30–50 cm.
Both the smooth, mottled bark and viscous, red, latex-rich resin excreted from the wounded trunk of the tree are used medicinally.
/sup> While the sap can be harvested with a tap much like natural latex from rubber trees, trees that are repeatedly tapped become vulnerable to fungal infections.
''Croton lechleri'' are native to the Amazon basin and are distributed across the tropical regions of the South American countries of Bolivia, Brazil
Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...
, Colombia, Ecuador
Ecuador ( ; ; Quechua: ''Ikwayur''; Shuar: ''Ecuador'' or ''Ekuatur''), officially the Republic of Ecuador ( es, República del Ecuador, which literally translates as "Republic of the Equator"; Quechua: ''Ikwadur Ripuwlika''; Shuar: ' ...
, Peru
, image_flag = Flag of Peru.svg
, image_coat = Escudo nacional del Perú.svg
, other_symbol = Great Seal of the State
, other_symbol_type = National seal
, national_motto = "Firm and Happy f ...
, and Venezuela
Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...
. They are most commonly found in the northwest lowlands between sea level up to 1000 m in elevation, mostly in mineral-rich disturbed soil and along rivers.
History
The earliest written reference to ''Croton lechleri'' dates to the 17th century, when Spanish Jesuit missionary, naturalist, and explorer, Bernabé Cobo
Padre Bernabé Cobo (born at Lopera in Spain, 1582; died at Lima, Peru, 9 October 1657) was a Spanish Jesuit missionary and writer. He played a part in the early history of quinine by his description of cinchona bark; he brought some to Europe o ...
encountered the use of the plant's resin by indigenous tribes throughout Mexico, Peru and Ecuador. This discovery was greatly overshadowed in Europe by his description of cinchona bark, or Jesuit's bark
Jesuit's bark, also known as cinchona bark, Peruvian bark or China bark, is a former remedy for malaria, as the bark contains quinine used to treat the disease. The bark of several species of the genus ''Cinchona'', family Rubiaceae indigenous t ...
, which was instrumental in the discovery and isolation of quinine
Quinine is a medication used to treat malaria and babesiosis. This includes the treatment of malaria due to '' Plasmodium falciparum'' that is resistant to chloroquine when artesunate is not available. While sometimes used for nocturnal le ...
.
Medicinal Use
Traditional Medicine
The resin of ''Croton lechleri,'' commonly known as sangre de drago, has a long history of medicinal use by indigenous peoples and is widely used in both urban and rural contexts in Peru and Ecuador, and to a lesser extent in other endemic countries. /sup> For centuries, the sap has been used to cover abrasions, cuts, scratches, blisters, bites and stings to prevent bleeding, decrease inflammation, seal wounds and injuries to protect from infection. The sap dries quickly on soft, damaged tissue, forming a barrier similar in thickness to the skin removed, noted as something akin to a "second skin." Antimicrobial activity offered by the plant is further believed to offer protection to the injury. The formation of this resistant barrier is likely due to the saps ability to co-precipitate with surrounding proteins or extracellular matrix elements. The hemostatic qualities relevant in wound healing that are associated with sangre de grado are further relevant to Amazonian indigenous communities in arresting the large amounts of bleeding following childbirth. Beyond cutaneous ailments, the use of sangre de grado is taken orally for gastrointestinal disorders and irregularities including gastritis, gastric ulcers, intestinal infections, and inflammation.
Modern Use and Clinical Research
Wound Care
Recent studies confirm the biochemical role played by the chemical composition of sangre de grado as a cicatrizant beneficial in the reduction of mean wound healing time. The polyphenolic compounds of the sap further create a protective layer at the wound surface, preventing the entry of pathogenic microbes. These compounds condense and bind to surrounding extracellular proteins, clogging the wound and offering vasoconstriction at the site of injury, which is crucial in wound healing. Taspine was found to be the principal cicatrizant agent in murine models as well as able to increase the chemotaxis of human fibroblast cells which is the most likely mechanism by which the resin and taspine accelerate the wound healing process. The chemotaxis of fibroblasts aids the reformation in the reformation of the matrix following re-epithelialization, allowing for the regeneration of damaged skin.
Antimicrobial Activity
Some compounds of the resin, as found in a particular study, 2,4,6-trimethoxyphenol, 1,3,5-trimethoxybenzene, crolechinic acid, and korberins A and B showed exhibited antibacterial properties individually. Sangre de grado from the closely related ''Croton urucurana'' was reported to exhibit antifungal qualities due to the presence of catechins and epigallocatechin contained in the resin, both of which are also found in ''Croton lechleri.'' In one study, disk diffusion method proved concentration-dependent antifungal activity against ''Trichophyton
''Trichophyton'' is a genus of fungi, which includes the parasitic varieties that cause tinea, including athlete's foot, ringworm, jock itch, and similar infections of the nail, beard, skin and scalp. Trichophyton fungi are molds characterize ...
'', ''Microsporum
''Microsporum'' is a genus of fungi that causes tinea capitis, tinea corporis, ringworm, and other dermatophytoses (fungal infections of the skin). ''Microsporum'' forms both macroconidia (large asexual reproductive structures) and microconi ...
'' and ''Epidermophyton
''Epidermophyton'' is a genus of fungus causing superficial and cutaneous mycoses, including ''E. floccosum'', and causes tinea corporis (ringworm), tinea cruris (jock itch), tinea pedis
Dermatophytosis, also known as ringworm, is a fung ...
'', three of the most common species of dermatophyte
Dermatophyte (from Greek '' derma'' "skin" ( GEN ''dermatos'') and ''phyton'' "plant") is a common label for a group of fungus of ''Arthrodermataceae'' that commonly causes skin disease in animals and humans. Traditionally, these anamorphic (a ...
s that cause superficial fungal infections of human skin. Further research is needed, however, to examine the role of sangre de grado from ''Croton lechleri'' as an effective antifungal agent in animal and human models.
Antiviral activity against influenza, parainfluenza
Human parainfluenza viruses (HPIVs) are the viruses that cause human parainfluenza. HPIVs are a paraphyletic group of four distinct single-stranded RNA viruses belonging to the '' Paramyxoviridae'' family. These viruses are closely associated wit ...
, Herpes simplex viruses I and II, and Hepatitis A
Hepatitis A is an infectious disease of the liver caused by ''Hepatovirus A'' (HAV); it is a type of viral hepatitis. Many cases have few or no symptoms, especially in the young. The time between infection and symptoms, in those who develop them ...
and B by ''Croton lechleri'' extracts and compounds have been exhibited. The most notable compound involved in antiviral activity is SP-303, also known as crofelemer, which has been heavily studied in vitro for its antiviral activity against the aforementioned viruses, as well as thymidine kinase mutants of HSV-1 and HSV-2 and acyclovir-resistant strains.
Antidiarrhoeal Activity
Crofelemer
Crofelemer (USAN, trade name Mytesi) is an antidiarrheal indicated for the symptomatic relief of non-infectious diarrhea in adult patients with HIV/AIDS on antiretroviral therapy. Other possible uses include diarrhea in children, acute infectious ...
, a purified proanthocyanidin oligomer extracted from the sap of ''Croton lechleri'' has been investigated for potential antidiarrhoeal activity. Various clinical studies have confirmed significant improvement in acute E. coli and V. cholera diarrhea cases from the administration of crofelemer. In the context of the principal luminal membrane determinants of intestinal fluid secretion, the mechanism of crofelemer action involves the inhibition of apical membrane cAMP-stimulated (CFTR) and calcium-stimulated (CaCC) Cl− channels by crofelemer molecules, with little effect on cation channels or cAMP/calcium signaling. As a result, fewer chloride ions are excreted into the bowel, decreasing the excretion of sodium ions and water, improving stool consistency and preventing diarrhea.
Up to 90% of individuals living with HIV face HIV-associated diarrhea, largely caused as a side effect of antiretroviral drugs such as nucleoside analog reverse transcriptase inhibitor
Reverse-transcriptase inhibitors (RTIs) are a class of antiretroviral drugs used to treat HIV infection or AIDS, and in some cases hepatitis B. RTIs inhibit activity of reverse transcriptase, a viral DNA polymerase that is required for replicati ...
s and protease inhibitors
Protease inhibitors (PIs) are medications that act by interfering with enzymes that cleave proteins. Some of the most well known are antiviral drugs widely used to treat HIV/AIDS and hepatitis C. These protease inhibitors prevent viral replicat ...
, which worsens with an increasingly compromised immune system. Various clinical have emphasized statistically significant efficacy crofelemer in HIV-associated diarrhea and restoration of digestive regularity. In 2012, a Phase III clinical trial for diarrhea in HIV patients was completed, and the drug was approved US Food and Drug Administration (FDA) the following year under the trade name Mytesi.
Chemistry
Proanthocyanidin
Proanthocyanidins are a class of polyphenols found in many plants, such as cranberry, blueberry, and grape seeds. Chemically, they are oligomeric flavonoids. Many are oligomers of catechin and epicatechin and their gallic acid esters. More compl ...
s are the main constituent of the resin produced by ''Croton lechleri,'' constituting more than 90% of its dry weight. The remaining 10% is largely alkaloid taspine, as well as catechin
Catechin is a flavan-3-ol, a type of secondary metabolite providing antioxidant roles in plants. It belongs to the subgroup of polyphenols called flavonoids.
The name of the catechin chemical family derives from ''catechu'', which is the tanni ...
, epigallocatechin
Gallocatechol or gallocatechin (GC) is a flavan-3-ol, a type of chemical compound including catechin, with the gallate residue being in an isomeric trans position.
This compound possesses two epimers. The most common, (+)-gallocatechin (GC), CAS ...
, epicatechin
Catechin is a flavan-3-ol, a type of secondary metabolite providing antioxidant roles in plants. It belongs to the subgroup of polyphenols called flavonoids.
The name of the catechin chemical family derives from ''catechu'', which is the tanni ...
, and low amounts of terpene
Terpenes () are a class of natural products consisting of compounds with the formula (C5H8)n for n > 1. Comprising more than 30,000 compounds, these unsaturated hydrocarbons are produced predominantly by plants, particularly conifers. Terpenes ...
compounds.
References
{{commons
lechleri
Plants described in 1866
Trees of western South America
Mutagens
Trees of Peru
Trees of Ecuador