Momordica charantia

 

Momordica charantia

Synonyms

No documentation.

Vernacular Name

African karela, Bitter Melon, Balsam Pear, Papailla, Bitter Gourd.

Description

Momordica charantia is an annual climbing vine of the family Cucurbitaceae. Growing to a length of up to 5m, M. charantia is a slender vine, which produces numerous tendrils, which allow it to be a proficient climber. The leaves of M. charantia are simple, glabrous and palmate, separated into three to seven lobes. Each leaf is roughly 4cm to 12cm across. The flowers of M. charantia bloom in early summer, typically. Each flower is bright yellow in colour and has five simple petals. Each petal is lightly pubescent and curls over itself at the tip.  The fruit borne of M. charantia is long, drupe and fleshy, most often green or yellow, but occasionally orange or red in colour. The skin of the fruit is most often much wrinkled, resembling a dehydrated cucumber. Each fruit is packed full of seeds which, when young appear white, but mature to a brilliant red in colour.

Origin / Habitat

M. charantia thrives in warm, moist tropical areas of the world including the Amazon rainforest and the tropics of Asia and Africa. It cannot tolerate cold temperatures and requires a soil pH of 5.5 to 6.5 in order to thrive. 

Chemical Constituents

Sterols (charantin), triterpenes (momorcharaside A and momorcharaside B), proteids (momorcharin A and B, MAP-30) [1].

Plant Part Used

Fruit and leaves [3][7].

Traditional Use

Karela has been used widely in Africa, with its highest concentration of use falling between the Tropic of Cancer and the Tropic of Capricorn [1].  In West Africa, Karela is most often used as to treat gastrointestinal disorders. More than 50% of traditional healers in Togo viewed Karela as being useful in treating general gastrointestinal debility [2]. In the Congo, macerated leaves are steeped in water and then ingested in order to treat general abdominal pain [3].A similar application of the leaves has been used traditionally in the Ivory Coast in order to treat diarrhea and dysentery and also used as a mild purgative [4]. In Western Nigeria, leaves of Karela are steeped in lemon juice, and used in order to treat diarrhea, cholera and dysentery [4]. Either an extract or an infusion of the fresh leaves, applied as an enema, has been used as an anthelmintic and astringent, respectively [2][5].

Karela has also been established by traditional African medical practitioners as being excellent for treating numerous external ailments. In cases of burns, macerated Karela leaves are combined with animal fat in order to make a paste which is then applied directly to the burns [4]. A decoctions made from the stems and leaves have been used in order to treat ulcers, septic swelling and boils.  Typically, the decoction is applied directly to the wound, or bathed in [2]. In Western Africa, malignant ulcers, and certain cancers are treated by applying a dressing containing the pulverized Karela leaves directly to the infected area [6]. In other areas of Western Africa, the fruit of Karela is used, either directly or as a decoction has been applied to burns ulcers and general wounds [7].

Other particularly notable traditional African applications of Karela include use as a hepatoprotective [7],  cardioprotective[2], and as a snakebite remedy [4].

Pharmacology

Pre-clinical

M.  charantia has been reported to significantly improve glucose tolerance in humans and laboratory animals [8][9] [10]. The currently accepted hypotheses regarding hypoglycemic activity is claimed to be mediated through an insulin secretagogue effect or through an influence on enzymes involved in glucose metabolism [11]. Research indicates that molecules with insulin-like bioactivity may be present in M.  charantia seeds [12].  A few studies suggest that the hypoglycemic mechanism of action of M.  charantia could be partly attributed to increased glucose utilization in the liver rather than an insulin secretion effect [13]. A recent laboratory study reported a significant reduction in fasting blood glucose levels observed in diabetic rats, but no hypoglycemic activity in the treated normal rats [14]. M.  charantia also showed considerable lowering of serum cholesterol and triglycerides in the treated diabetic group. There was a significant improvement in hepatic glycogen level in treated diabetic rats, with a return of close to normal levels after the treatment with M.  charantia . There have been negative reports as to the ability of M.  charantia extracts to lower blood sugar levels in laboratory animals [15][16]. It is recommended that a standardized extract of M.  charantia always be used.

The effect of M.  charantia on fasting and post prandial serum glucose levels was studied in 100 cases of moderate non-insulin dependent diabetic subjects [17].  Drinking of an aqueous homogenised suspension of the vegetable pulp led to a significant reduction of both fasting and post-prandial serum glucose levels. This hypoglycemic action was observed in 86 (86%) cases. Five cases (5%) showed lowering of fasting serum glucose only. Another interesting study reported on the effects of freeze-dried M.  charantia powder on serum glucose level and lipid parameters of the serum and liver were studied in laboratory rats [18].  M.  charantia administration resulted in a consistent decrease in serum glucose levels in rats fed cholesterol-free diets, but not in those fed cholesterol-enriched diets, with no dose-response noted. The authors reported that  M.  charantia product had little effect on serum lipid parameters, except for high density lipoprotein (HDL)-cholesterol; however, HDL-cholesterol levels tended to decrease by dietary cholesterol, while they were consistently elevated by dietary M.  charantia both in the presence and absence of dietary cholesterol, indicating an antiatherogenic activity of M.  charantia . In addition, M.  charantia exhibited a marked reduction in the hepatic total cholesterol and triglyceride levels both in the presence and absence of dietary cholesterol, with the reduction of triglyceride levels in the absence of dietary cholesterol being in a dose-dependent manner.

The mature fruits of M.  charantia have been used externally for the rapid healing of wounds and internally for the treatment of peptic ulcers in Turkish folk medicine. A recent laboratory animal study reported that a potent and dose-dependent inhibitory activity was observed by the administration of ethanol extract of the fruits in peptic ulcer induced by HCL-EtOH and indomethacin in rats [19].

An anti-HIV plant protein has been identified and purified from M.  charantia that is capable of acting against multiple stages of the viral life cycle, on acute infection as well as replication in chronically infected cells [20][21]. The anti-viral agent from M.  charantia is capable of inhibiting infection of HIV type 1 (HIV-1) in T lymphocytes and monocytes as well as replication of the virus in already-infected cells. MAP30 seems to be non-toxic to normal uninfected cells because it is unable to enter healthy cells [22].The MAP30 protein has also been reported to be effective against estrogen-dependent human breast cancer MDA-MB-231 in vitro and in vivo, and also a novel antigenic agent against neurofibrillary tangles Alzheimer's disease [23][24]. Another study indicated that a Thai bitter gourd protein (MRK29), isolated from the ripe fruit and seed of Momordica charantia demonstrated inhibition of HIV-1 reverse transcriptase [25].

A recent laboratory study reported that alpha-momorcharin (alpha-MMC) isolated from M.  charantia fruit was found to inhibit HIV-1 III B-inducing syncytia formation and markedly reduced both expression of p24 core antigen and the numbers of HIV antigen positive cells in acutely but not chronically HIV-1-infected culture [26].

In addition to antiviral action, the protein, termed MAP30, also possesses anti-tumor activity, topological inactivation of viral DNA, inhibition of viral integrase and cell-free ribosome-inactivation activities [21]. Another study completed in rats determined that M.  charantia significantly inhibited aberrant crypt focus formation in the colon noting the potential chemoprotective nature of M.  charantia against colon carcinogenesis [27].

Topical application of an extract of M.  charantia fruit has been reported to be inhibitory on mouse skin papillomagensis with the modulatory influence of biotransformation system enzymes [28].

Clinical

No documentation.

Interaction and Depletions

Interaction with other Herbs

No documentation.

Interaction with Drugs

No documentation.

Precautions and Contraindications

Side effects

Do not use in individuals with existing liver disease including alcoholic cirrhosis [29].

Discontinue if allergy occurs.

Pregnancy

Based on animal data, do not use in pregnancy due to abortifacient activity [30]. If nursing, consult a physician before use.

Age limitation

No documentation.

Adverse reaction

No documentation.

Read More

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  3) South Central America Herbs

  4) Ayuverda

References

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  2. Beloin N, Gbeassor M, Akpagana K, Hudson J, de Soussa K, Koumaglo K, Arnason JT. Ethnomedicinal uses of Momordicacharantia (Cucurbitaceae) in Togo and relation to its phytochemistry and biological activity. J Ethnopharmacol. Jan. 4, 2005;96(1-2):49-55.
  3. Neuwinger HD. African Traditional Medicine: A Dictionary of Plant Use and Applications. Stuttgart, Germany: Medpharm Gmbh Scientific Publishers; 2000:338-339
  4. Baerts-Lehmann M, Lehmann J. Prelude Medicinal Plants Database. Catholic University of Louvain; 2007. Available from: http://www.metafro.be/prelude. [Accessed on February 21, 2009]
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  6. Burkill HM. The Useful Plants of West Tropical Africa; Vol 1. Kew, UK.  Royal Botanical Gardens, Kew: 1985.
  7. Rasoanaivo P, Petitjean A, Ratsimamanga-Urverg S, Rakoto-Ratsimamanga A. Medicinal plants used to treat malaria in Madagascar. J Ethnopharmacol. Sep. 1992;37(2):117-127.
  8. Sitasawad SL, Shewade Y, Bhonde R. Role of Bittergourd Fruit Juice in Stz-induced Diabetic State In Vivo and In Vitro. J Ethnopharmacol. Nov. 2000;73(1-2):71-79.
  9. Leatherdale BA, et al. Improvement in Glucose Tolerance Due to Momordica charantia (Karela). Br Med J. (Clin Res Ed). Jun. 1981;282(6279):1823-1824.
  10. Welihinda J, et al. Effect of Momordica charantia on the Glucose Tolerance in Maturity Onset Diabetes. J Ethnopharmacol. Sep. 1986;17(3):277-282.
  11. Platel K, et al. Plant Foods in the Management of Diabetes Mellitus: Vegetables as Potential Hypoglycaemic Agents. Nahrung. Apr. 1997;41(2):68-74.
  12. Ng TB, et al. Insulin-Like Molecules in Momordica charantia Seeds. J Ethnopharmacol. Jan. 1986;15(1):107-117.
  13. Sarkar S, et al. Demonstration of the Hypoglycemic Action of Momordica charantia in a Validated Animal Model of Diabetes. Pharmacol Res. Jan. 1996;33(1):1-4.
  14. Rao BK, et al. Antidiabetic and Hypolipidemic Effects of Momordica cymbalaria Hook. Fruit Powder in Alloxan-diabetic Rats. J Ethnopharmacol. Oct. 1999;67(1):103-109.
  15. Patel K, et al. Effect of Dietary Intake of Freeze Dried Bitter Gourd (Momordica charantia) in Streptozotocin Induced Diabetic Rats. Nahrung. 1995;39(4):262-268.
  16. Ali L, et al. Studies on Hypoglycemic Effects of Fruit Pulp, Seed, and Whole Plant of Momordica charantia on Normal and Diabetic Model Rats. Planta Med. Oct. 1993;59(5):408-412.
  17. Ahmad N, Hassan MR, Halder H, et al. Effect of Momordica charantia (Karolla) Extracts on Fasting and Postprandial Serum Glucose Levels in NIDDM Patients. Bangladesh Med Res Counc Bull. Apr. 1999;25(1):11-13.
  18. Jayasooriya AP, Sakono M, Yukizaki C, et al. Effects of Momordica charantia Powder on Serum Glucose Levels and Various Lipid Parameters in Rats Fed With Cholesterol-free and Cholesterol-enriched diets. J Ethnopharmacol. Sep. 2000;72(1-2):331-336.
  19. Gurbuz I, Akyuz C, Yesilada E, et al. Anti-ulcerogenic Effect of Momordica charantia L. Fruits on Various Ulcer Models in Rats. J Ethnopharmacol. Jul. 2000;71(1-2):77-82.
  20. Lee-Huang S, et al. Anti-HIV and Anti-Tumor Activities of Recombinant MAP30 From Bitter Melon. Gene. Aug. 1995;161(2):151-156.
  21. Bourinbaiar AS, Lee-Huang S. Potentiation of Anti-HIV Activity of Anti-inflammatory Drugs, Dexamethasone and Indomethacin, by MAP30, the Antiviral Agent from Bitter Melon. Biochem Biophys Res Commun. Mar. 1995;208(2):779-785.
  22. Lee-Huang S, et al. Inhibition of the Integrase of Human Immunodeficiency Virus (HIV) Type 1 by Anti-HIV Plant Proteins MAP30 and GAP31. Proc Natl Acad Sci. Sep. 1995;92(19):8818-8822.
  23. Liu Z. Microtubule-associated Protein30 (MAP30) and Ubiquitin Detected in Neurofibrillary Tangles of Alzheimer's Disease Brains. Hunan I Ko Ta Hsueh Hsueh Pao. 1998;23(1):11-13.
  24. Lee-Huang S, Huang PL, Sun Y, et al. Inhibition of MDA-MB-231 Human Breast Tumor Xenografts and HER2 Expression by Anti-tumor Agents GAP31 and MAP30. Anticancer Res. Mar. 2000;20(2A):653-659.
  25. Jiratchariyakul W, Wiwat C, Vongsakul M, Somanabandhu A, Leelamanit W, Fujii I, et al. HIV inhibitor from Thai bitter gourd. Planta Med. Jun. 2001;67(4):350-353.
  26. Zheng YT, Ben KL, Jin SW. Alpha-momorcharin Inhibits HIV-1 Replication in Acutely but Not Chronically Infected T-lymphocytes. Chung Kuo Yao Li Hsueh Pao. Mar. 1999;20(3):239-243.
  27. Chiampanichayakul S, Kataoka K, Arimochi H, Thumvijit S, Kuwahara T, Nakayama H, et al. Inhibitory effects of bitter melon (Momordica charantia Linn.) on bacterial mutagenesis and aberrant crypt focus formation in the rat colon. J Med Invest. Feb. 2001;48(1-2):88-96.
  28. Singh A, et al. Momordica charantia (Bitter Gourd) Peel, Pulp, Seed and Whole Fruit Extract Inhibits Mouse Skin Papillomagenesis. Toxicol Lett. Jan. 1998;94(1):37-46.
  29. Tennekoon KH, et al. Effect of Momordica Charantia on Key Hepatic Enzymes. J Ethnopharmacol. Oct. 1994;44(2):93-97.
  30. Leung SO, et al. The Immunosuppressive Activities of Two Abortifacient Proteins Isolated from the Seeds of Bitter Melon (Momordica charantia). Immunopharmacology. Jun. 1987;13(3):159-1.