Plants are better chemist than humans – Part 2?
Continued from last week
Many flowering plants in nature and cultivated gardens all over the world aren’t just beautiful to be used only as ornamentals, they are also carriers of properties with powers to heal diseases and treat various ailments of humans and animals.
For example, Chemoprevention represents a different attitude in the battle against cancer. This approach was defined as the ingestion of dietary or pharmaceutical compounds to prevent or delay carcinogenic processes.
Many potential chemopreventive secondary metabolites in both extracts and purified molecules isolated from teas, herbs, fruits and vegetables have been explored.
Curcumin (diferuloylmethane) is the most prominent chemopreventive agent studied. This yellow-orange turmeric powder is a polyphenol that accumulates in the rhizome of Curcuma longa.
Both TCM and TIM have used Curcuma as a medicine for the treatment of diseases due to its capabilities to regulate important transcription factors, cytokines, protein kinases, adhesion molecules and redox status.
Curcumin can serve as an anti-inflammatory, anti-oxidant, anti-proliferative, anti-angiogenic and anti-neoplastic agent. Thus it has been used to treat many different conditions such as neurodegenerative diseases, cardiovascular diseases, diabetes, allergy, asthma and bronchitis, inflammatory bowel diseases, rheumatoid arthritis, renal ischemia, psoriasis, scleroderma, Acquired Immuno-deficiency Syndrome (AIDS) and cancer. It is also an anti-ageing and scar formation agent.
Curcumin can act also as a chemopreventive agent of photocarcinogenesis by protecting the skin from diminishing oxidative stress and suppressing inflammation. Curcumin has been shown to affect microtubule assembly, leading cells to mitotic arrest. Recently, this type of action by curcumin was found non-specific only to cancer cells, implying its possible impact also on normal cells. Therefore, additional studies to assure this plant-derived substance influences normal cells and is used in combination with other anti-cancer drugs are required.
Cannabis sativa has also been used in the TCM mainly to treat malaria, constipation, rheumatic pains and childbirth pains. It was only in the nineteenth century that an Irish scientist and physician, O’ Shaughnessy found that in India, it is used as an analgesic, anticonvulsant, antispasmodic, anti-emetic, and hypnotic agent. These observations caused its spread into Europe and USA until it was outlawed in 1928 and 1937, respectively due to its negative effects.
The plant, cannabis sativa, is known to contain more than 60 compounds. The first active compound isolated from cannabis sativa was tetrahydrocannabinol (THC). The active components of marijuana cannabinoids are mainly used in the last two centuries as supporting drugs for patients that received either radiation or chemotherapies. These drugs ease common symptoms and side effects of such treatments as nausea, vomiting, cachexia, and loss of appetite.
The use of cannabinoids as anti-cancer agents is still under debate due partly to the cancer-promoting and inhibiting effects shown in the last centuries.
The use of herbal medicines offers a way to alleviate the crisis in drug development. There are three main advances for herbal medicines: (1) utilizing the traditional herbal medicine knowledge may give rise to an inexpensive and more rapid discovery of new drugs; (2) herbal remedies offer a holistic approach that complements the disease-targeting approach of silver bullet; (3) synergy between the various components of the herbs are an important element of their overall medical effects.
The main disadvantage related to herbal medicines is the lack of international standardization in terms of methods for evaluating their composition, efficacy, safety and quality, consistent manufacturing practices, regulation and approval process.
Ironically, vast knowledge and experience in drug development are available in the pharmaceutical industry. Therefore, combining the benefits provided by both traditional and modern medicine has been previously suggested as a promising approach to revealing and bringing to market new plant-derived substances.
However, in the last centuries, only several herbal medicines or botanical drugs have been approved by health authorities for human use, collaboration and coordination between World Health Organization (WHO), Federal Drug Administration (FDA), and European and other regulatory agencies.
The pharmaceutical industry worldwide may lead to clear guidance for the development of herbal medications while taking advantage of the huge potential held by traditional medicine for the development of both anti-cancer and other health-promoting drugs.
There is also much interest in the role of plant chemicals in our diet that may help protect against some diseases such as cancer and Alzheimer’s, and the role that plants may play to support health, and to prevent or alleviate some diseases such as dementia.
Plants have long been a key source of important drugs that we have continued to use till today. We can harness the power of the natural world to save lives, and do it in a way that protects the plant kingdom too.