The kalanchoe and its medicinal properties, what is true?

Kalanchoe  sp. it is a genus of succulent plants comprising about 125 species. Like all succulent plants, they accumulate water in their tissues and are adapted to life in warm environments. They are frequently cultivated for ornamental use due to the fact that many species have showy flowers and their great resistance to drought.

A striking feature of these plants, although present in other families, is their asexual reproduction . In some species, such as Kalanchoe daigremontiana , the adult individuals generate small seedlings on the edge of their leaves, which develop roots and fall to the ground, giving rise to new individuals.

 Kalanchoe medicinal properties

Many are the plants that have been traditionally used in different cultures to fight diseases or provide health benefits. A well-known example of this is salicylic acid, from which acetylsalicylic acid, better known as Aspirin, is obtained. The salicylic acid is present in the cortex of the willows (whose Latin name is Salix , hence the name of the compound), and were several cultures who knew the medicinal properties of willow bark before it was isolated compound.

Some plants of the genus Kalanchoe have been used in traditional medicine to treat infections, rheumatism and inflammation . To give a concrete example, in Trinidad and Tobago Kalanchoe pinnata was used to combat hypertension.

The modern science insulates different compounds from plants and check its effect in different tissues or cells, either in vitro in conditions (with tissues or cells within a petri dish) or in vivo (in studies usually using live mice , due to the simplicity of its handling in the laboratory and the similarities between its nervous and immune systems with those of the human body).

That a compound shows a certain behavior in vitro does not imply that it has the same effect in vivo. Nor can a good result be extrapolated in in vivo tests with mice to humans, since the responses may not be the same.

In the species K. pinnata , belonging to the genus Kalanchoe , three flavonoids have been discovered that are effective against the parasite that causes the leishmaniasis disease ( Leishmania amazonensis ). These compounds, whose full names are quite long, are a kaempferol, a quercetin, and a dimethoxyflavone. At the moment they have only been detected in K. pinnata , being absent in the rest of the species of the genus. However, recent studies have discovered new substances present in other plants of the genus, and this has raised a real powder keg. 

The anti-cancer effect of Kalanchoe

It is a fairly widespread error in current times to believe that, if a chemical compound that has anticancer properties (preventing the spread of tumors, for example) is discovered in a plant under laboratory conditions, consuming the plant directly will have the same effect on the body.

Furthermore, it is believed that this plant will replace the current therapies used in cancer treatments , such as chemotherapy. Perhaps the best known example of this is cannabis, derived from the hemp plant ( Cannabis sativa ).

Far from replacing chemotherapy, if one of these compounds is discovered and its efficacy is proven, it is refined and becomes part of chemotherapy treatments. The vincristine and vinblastine are two alkaloids extracted from Vinca Madagascar, Catharanthus roseus , and used to treat cancers, such as leukemia, breast cancer or Hodgkin's lymphoma. The alkaloids are substances present in many plants and that present a high toxicity, which makes these plants poisonous. Madagascar vinca is a toxic plant due to the amount of alkaloids it contains, but two of them are used as effective drugs once isolated.

In recent years, bufadienolide compounds have been discovered in various species of the genus Kalanchoe . They are K. pinnata , K. tubiflora and K, gracilis . These substances have been able to reduce the growth of tumors, both in vitro and in vivo. But, and this is a very important but, in vivo studies have only been done in mice to date. For now the results are promising.

Isn't it good news that new ways to fight cancer are being discovered? Of course. But these things must be done rigorously. These bufadienolides have not even been shown to be capable of stopping tumor growth in humans. And, if they were, they would need to be refined and properly administered as part of a chemotherapy treatment.

Of the 125 species that make up the genus, only in 3 have these substances been discovered and their effect on humans has not been demonstrated. So, for now at least, news of a miraculous plant that cures cancer is nothing but smoke.

Sources

• Kalanchoe: The Genus and its Chromosomes. American Journal of Botany 25 (8). October 1938. pp. 572-579.
• The antileishmanial activity assessment of unusual flavonoids from Kalanchoe pinnata . Muzitano MF, Tinoco LW, Guette C, Kaiser CR, Rossi-Bergmann B, Costa SS. Phytochesmistry. Volume 67, Issue 18, September 2006, Pages 2071–2077.
• Kalanchosides A − C, New Cytotoxic Bufadienolides from the Aerial Parts of Kalanchoe gracilis . Wu PL, Hsu YL, Wu TS, Bastow KF, Lee KH. Org. , 2006, 8 (23), pp 5207–5210.
• Anti-tumor promoting activity of bufadienolides from Kalanchoe pinnata and daigremontiana x tubiflora . Supratman U, Fujita T, Akiyama K, Hayashi H, Murakami A, Sakai H, Koshimizu K, Ohigashi H. Biosci Biotechnol Biochem. 2001 Apr; 65 (4): 947-9.
• Anticancer activity of Kalanchoe tubiflora extract against human lung cancer cells in vitro and in vivo. Hsieh YJ, Huang HS, Leu YL, Peng KC, Chang CJ, Chang MY. Environ Toxicol. 2016 Nov; 31 (11): 1663-1673. doi: 10.1002 / tox.22170. Epub 2015 Jul 15.
• Isolation and Characterization of Antineoplastic Alkaloids from Catharanthus Roseus Don. Cultivated in Egypt. Shams KA, Nazif NM, Azim NSA, Shafeek KAA, El-Missiry MM, Ismail SI, El Nasr MMS. Afr J Tradit Complement Altern Med. 2009; 6 (2): 118–122.