Medicinal Plants for Cancer Treatment - Research Paper Example

Medicinal Plants for Cancer Treatment Introduction: The use of plants in the treatment and prevention of diseases is as old as the history of humankind itself. Medicine as it existed in the ancient civilizations like the Indian, Chinese, and Egyptian civilizations essentially depended on plants to provide the means to combat and prevent diseases. Elements of this practice have remained in the traditional practice of medicine among many communities around the world, which provides an insight into the beneficial use of plants in the treatment diseases. Modern medicine has started evaluating and using medicinal plants in the treatment of many diseases that have remained a challenge in spite of the many advances in medical science and technology. An example of this lies in the reduced risk of cancer through the high consumption of vegetables and fruits that evidence from epidemiological has suggested. Such evidence has led to modern medicine evaluating the potential chemo-preventive benefits of naturally occurring phytochemicals in fruits and vegetables (Park & Pezzuto, 2002). Range and Action of Medicinal Plants: History has demonstrated that plants have been used for disparate intervention strategies to ease, treat and manage a wide range of diseases and conditions. On one side we have a range of plants that offer medically oriented benefits. These plants include those that form a part of our daily diet like cabbage, broccoli, garlic, onion, citrus fruits, tomatoes, onions, berries, ginger and ginseng. Besides these examples of plants that are used on a regular basis, there is a host of medicinal plants that are used solely for the medicinal benefits they offer. Since the growth of plants is depended on climate and soil patterns, the use of these plants vary from region to region and in most of Asia, Africa, and Central and South America, where traditional medicine is still practiced, different plants are employed for different medical purposes (Park & Pezzuto, 2002). On the other side we have a range of medical ailments that are treated with the help of medicinal plants. These medical ailments are not restricted to any particular type or classification. The range of medical ailments that can be treated with the help of medicinal plants have a wide range from infections to diabetes to cardiovascular disorders to neurodegenerative disorders, and hence present a very large spectrum of activity. Such a wide range of activity cannot come from a single pharmacological agent present in plants, but must come from a wide range of active ingredients in plants that allow for such a wide action. Studies have revealed that there are a wide range of medically beneficially chemical agents present in plants that are responsible for the different roles played in the traditional modes of treatment of disparate diseases. These pharmaceutically active agents include alkaloids, phenolics, tannins, carotenoids, tocopherol, catalase, glutathione, and quercetin. (Ali, et al, 2008). Rationale for the role of Medicinal Plants in the Treatment of Cancer: Medicinal plants have been used traditionally and in modern medicine for the treatment of non-infectious and infectious ailments. Estimates suggest that as much as twenty-five percent of pharmaceutical agents currently employed by modern medicine contain compound isolated from plants. Medicinal plants offer modern medicine a vast repository for drug discovery to combat non-infectious and infectious diseases. This is particularly significant, when there is the realization that improved separation technologies available makes it easier to extract beneficial plant compounds to enable us to meet the challenges of complex diseases like AIDS and cancer, which continue to resist the attempts to develop efficient cost-effective treatment and therapeutic strategies (Mukhtar, et al, 2008). The world experiences almost ten million new cancer cases every year, which is the cause of 7.6 million deaths annually. The death toll due to cancer is so high that it makes up thirteen percent of all deaths seen around the world. These figures put cancer among the most devastating diseases that is being experienced by humankind. Prospects for the immediate future in spite of all the developments in medical science and technology and the emerging new therapeutic agents and drug delivery systems, estimates suggest that mortality from cancer will continue to rise with almost nine million people dieing from cancer in 2015. This makes combating cancer through all the resources available an essential component of medical science. Medicinal plants are one such resource that has yet to be efficiently deployed in combating cancer (Pujol, et al, 2007). Besides the enhancement potential of that medicinal plants offer in the medical arsenal against cancer, another benefit is the possibility of reducing the cost of treatment of cancer. The huge costs currently associated in the treatment of cancer are responsible for the denial of the benefits of potentially effective therapeutic agents to many of the patients of cancer, because they cannot afford it. Such a denial leads to the progress of the disease and their early demise (Chusteka, 2008). A major issue concerning the current range of drugs available for use in chemotherapy for the treatment of cancer is in their toxicity. They produce a wide range of side effects that has led to the passing refrain that the treatment for cancer is worse than the disease itself. In addition to these side effects many of the anti-cancer drugs employed today not only destroy the cancerous cells, but also the normal cells, giving rise to serious concern on the toxic effect of these drugs on patients suffering from cancer. Medicinal plants offer us a means to drugs to combat patients without the problem of toxicity and side effects. Many plants that form our normal diet offer scope to be used to fight cancer and the other medicinal plants are not likely to create issues of toxicity and side effects, enlarging the scope of their use without discomfort to the patients (Zhu, et al, 2007). Thus there are several reasons why medicinal plants are essential to the medical arsenal that can be deployed to combat a disease as devastating as cancer. Medicinal plants offer a wide range of possibilities to this medical arsenal against cancer. Examples of Plants in the Treatment of Cancer: From the vegetables that we consume to plants around us there is a repository of means to fight cancer. Cancer-fighting derivatives have even been isolated from the weeds around us and are already in use to combat cancer. Examples of this lie in vinblastine a weed derivative used in Hodgkin’s disease and vincristine another weed derivative employed in childhood leukemia. The potential use of commonly found plants as a source to combat cancer has caused John Richard Stepp, an anthropologist from the University of Florida to state “the realization that medicinal plants are a readily available pharmacy outside the door and along the sides of trails rather than deep in the forest could lead governments to encourage and promote traditional practice. He goes on to add “they are readily available, cost nothing to gather, and are often more effective” (Weeds as Medicines). Commonly available or cultivated plants and other medicinal plants make a wide source of potential means to combat of which there are many being evaluated. Garlic and Onion: Garlic (Allium sativum) and onion (allium) are two of the oldest cultivated plants in the history of humankind and a common spice ingredient in the food that is commonly consumed. Traditional medicine has employed these two plants for their beneficial effects in their treatment methods and is one of the most researched and known plants to traditional medicine. The range of activity of these two commonly known plants is amazing, as it has been known to be used as an antiseptic, anti-thrombotic, hypolipidemic, and anti-arthritic. Modern medical science is examining the potential insecticidal, anti-microbial, anti-protozoal, and anti-tumor beneficial properties of these two medicinal plants (Ali, Thomson & Afzal, 2000). The anti-tumor properties of garlic has been known since ancient times and employed even then to inhibit the growth of tumors in the ancient Indian and Egyptian civilizations. The current thrust of its evaluation of garlic and onion in modern medicine is focused on several aspects that include chemoprevention. According to Ali, Thomson, and Afzal, 2000, “a compound that can inhibit the carcinogenic process is called an anticarcinogen or chemopreventive. Cancer affects different parts or organs of the body. To study the possible chemopreventive potential of garlic and onion, on the several forms of cancer, various preparations, like fresh extract, aged garlic or onion extract, garlic oil and several organosulfur compounds extracted from garlic and onion (Ali, Thomson & Afzal, 2000). The mode of action through which garlic and onion show promise of chemoprevention is not clear, but there is clear indication that these potential benefits that garlic and onion offer in chemoprevention arise from the compounds that are present in them with particular emphasis on the organosulfur compounds. The organosulfur compounds in garlic and onion give them their characteristic pungent taste and smell and are also firmly associated with the chemopreventive benefits derived from garlic and onion. An interesting development in the evaluation of the chemopreventive benefits of garlic and onion is the presence of more polar compounds of phenolic and steroidal origin with pharmaceutical properties that may offer potential chemopreventive benefits. These compounds do not have the pungency associated with the organosulfur compounds and more importantly are more stable to cooking increasing the potential use of garlic and onion chemopreventive properties through the dietary means instead of other modes of administration normally associated with pharmacological agents (Lanzotti, 2006). Cruciferous Vegetables: The objective of chemoprevention is to delay the onset of cancer and also the incidence of cancer. Effective means to chemoprevention essentially requires the utilization of nontoxic agents that act as inhibitive agents to the several specific molecular steps involved in the carcinogenic pathway. Diet is a means of addressing the goal of chemoprevention and the cruciferous vegetables, which form a part of normal diet, component of diet to achieve chemoprevention (Fimognari & Hrelia, 2007). Vegetable consumption is an essential part of a balanced daily diet. The cruciferous vegetables of broccoli, cauliflower, cabbage, kale, Brussels sprouts, and radish are more strongly linked to the anti-cancer properties than any other vegetable. This is because the cruciferous vegetables contain many bioactive compounds like flavanoids, minerals like selenium, and vitamins like vitamin C. A group of compounds of significant interest found in the cruciferous vegetables is the isothiocynate group. The reason for this interest is the capability of the isothiocynates to modulate the various stages of the development of cancer, and thus offer the means of simultaneously modulating multiple cellular targets involved in the development of cancer. Such multiple modulations include DNA protection through the modulation of carcinogen-metabolizing enzymes and blocking the action of mutagens, and inhibition of cell proliferation and induction of apoptosis (Fimognari & Hrelia, 2007). Ginger: Ginger is the rhizome of Zungiber officinalis, which is a well known and a frequently used condiment used in the preparation of several foods and beverages. It is another plant that has seen medicinal use that dates back to the ancient civilizations. There are pungent constituents present in the ginger and the zingiberaceous plants that demonstrate potent antioxidant properties. In experimental carcinogenesis some of these potent antioxidant properties of ginger and the zingiberaceous plants exhibit cancer preventive activity. The constituents of ginger associated with the cancer preventive activity are believed to be certain vallinoids like gingerol and paradol, and shogaols, and zingerone (Shukla & Singh, 2007). Herbal and Medicinal Plants: Herbal and medicinal plants have a long history of curative powers employed by traditional branches of medicines of different regions of the world for the treatment of infectious and non-infectious diseases. One of the regions of the world that abound in the use of herbal and medicinal plants is Asia, with the traditional branches of Indian medicine and Chinese medicine still remaining popular in this region. Evaluation of the curative powers of these herbal and medicinal plants has already thrown up the potential use of some herbal and medicinal plants in the treatment of cancer, even though the evaluation has not been exhaustive as yet (Ali, et al, 2008). A vast majority of the synthetic chemotherapeutic agents employed in the treatment of cancer are immunosuppressant, cytotoxic and produce a wide variety of side effects during their use in chemotherapy in the treatment of cancer. Many of the currently herbal and medicinal plant derived chemotherapeutic agents are immunomodulators that are used as supportive or adjuvant therapy to reduce or overcome the undesired effects of the cytotoxic synthetic chemotherapeutic agents, and through that bring about a restoration of normal health. Such benefits of botanical derivates are seen in the case of medicinal plants like Withania somnifera, Tinospora cordifolia, and Asparagus racemouse. Thus one of the initial benefits that can be derived by the use of herbal and medicinal plants in the treatment of cancer is the reduction of undesired side effects of the currently employed synthetic chemotherapeutic agents in the treatment of cancer (Diwanay, Chitre & Patwardhan, 2004). The roles of herbal and medicinal plants are not restricted to that of chemoprevention or as an adjuvant therapy to reduce the side effects of the cytotoxic synthetic chemotherapeutic agents. Promise is held out by several herbal and medicinal plants to perform chemotherapeutic functions, because of the chemotherapeutic compounds contained by them. The traditional Indian medicine Rasaganthi Lehyam, derived from medicinal herbs, shows potential for the treatment of ling cancer. Rasaganthi Lehyam has five fractions, of which one is a chloroform fraction. Evidence is emerging of that this chloroform fraction inhibits cell proliferation and causes induction of apoptosis of in the two lung cancer cell lines of A-549 and H-460, but does not act on the normal bronchial epithelial cell line. This is an example of the possible chemotherapeutic effect of herbal and medicinal plants without the side effects seen in synthetic chemotherapeutic agents (Ranga, et al, 2005). Additional evidence is emerging on the potential chemotherapeutic effects of herbal and medicinal plants. Extracts of the genus Aglaia is used in China and the South-East Asian countries like Vietnam as an insecticide with no substantial toxic effects on animals or humans. Roclagamide has been identified as the active ingredient in these extracts. Evaluation of roclagamide has shown that it inhibits the cell proliferation of some human leukemia cell lines through a cytostatic effect, holding out promise for development as a chemotherapeutic for leukemia (Zhu, et al, 2007). Conclusion: Treatment of the devastative disease of cancer remains a challenge to modern medicine. In spite of the several advances made treatment of cancer continues to remain a vexing problem to modern medicine due to the lack of effective synthetic chemotherapeutic agents to treat cancer efficiently, the side of effects of these synthetic chemotherapeutic agents, and the immense costs involved in the use of these synthetic chemotherapeutic agents in the treatment of cancer. Human kind may have to fall back on the backbone of traditional medicine namely medicinal plants to find an effective means to combat the dreaded disease of cancer. Medicinal plants or their derivates hold out the promise of combating cancer without the problems associated with the synthetic chemotherapeutics through enhanced efficacy, lower or hardly any side effects, and much lower costs. Plants are already employed in several roles in the fight against cancer. Many commonly used vegetables have chemopreventive properties and through their enlarged use in daily diets pave the way for chemoprevention of cancer. Medicinal plant derivatives occupy a place as adjuvant therapies in the treatment of cancer, so as to reduce the side effects of the synthetic chemotherapeutics used in the treatment. Evidence emerging from the studies of medicinal plants indicates that medicinal plants or their derivatives have the potential of chemotherapeutic effect on different forms of cancer. Thus medicinal plants may be employed with much larger effect in the treatment of cancer in the near future. Literary References Ali, M., Thomson, M. & Afzal, M. (2000). Garlic and onions: their effect on eicosanoid metabolism and its clinical relevance. Prostaglandins, Leukotrienes and Essential Fatty Acids, 62(2), 55-73. Ali, S. S., Kasoju, N., Luthra, A., Singh, A., Sharanabasava, H., Sahu, A. & Bora, U. (2008). Food Research International, 41, 1-15. Chustecka, Z. (2008). Extended Approval of Herceptin Welcomed by US Experts, but UK Physicians Remain Concerned About Cost. Retrieved March 29, 2008, from Medscape News, Medscape Today Web Site: http://www.medscape.com/viewarticle/548248 Diwanay, S., Chitre, D. & Patwardhan, B. (2004). Immunoprotection by botanical drugs in cancer chemotherapy. Journal of Ethnopharmacology, 90(1), 49-55. Fimognari, C. & Hrelia, P. (2007). Sulforaphane as a molecule for fighting cancer. Mutation Research, 635, 90-104. Lanzotti, V. (2006). The analysis of onion and garlic. Journal of Chromatography, 1112, 3-22. Mukhtar, M., Arshad, M., Ahmad, M., Pomerantz, J. R., Wigdahl, B. & Parveen, Z. (2008). Antiviral potentials of medicinal plants. Virus Research, 131, 111-120. Park, J. E. & Pezzuto, M. J. (2002). Botanicals in Cancer Chemoprevention. Cancer and Metastasis Reviews, 21(3-4), 231-255. Pujol, M., Gavilondo, J., Ayala, M., Rodriguez, M. Gonzales, M. E. & Perez, L. (2007). Fighting cancer with plant-expressed pharmaceuticals. Trends in Biotechnology, 25(10), 456-459. Ranga, S. R., Sowmyalakshmi, S., Burikhanov, R., Akbarsha, A.M. & Chendil, D. A herbal medicine for the treatment of lung cancer. Molecular and Cellular Biochemistry, 280, 125-133. Shukla, Y. & Singh, M. (2007). Cancer preventive properties of ginger: A brief review. Food and Chemical Chemical Toxicology, 45(5), 683-690. Weeds as Medicines. (2004). THE FUTURIST, September-October, 2004, p.11. Zhu, Y. J., Larvik, N. I., Mahlknecht, U., Giaisi, M., Proksch, P, Krammer, H. P. & Lo-Weber, M. (2007). International Journal of Cancer, 121, 1839-1846. Read More