Inhibition of tumor growth and angiogenesis by water extract of Gac fruit (Momordica cochinchinensis Spreng).
Department of Integrated Medicine 1, Jichi Medical School, Omiya Medical Center, 1-847 Amanuma-cho, Saitama 330-8503, Japan.
The antitumor activity of the crude water extract from Gac fruit (Momordica cochinchinensis) was investigated in vivo and in vitro. A water extract prepared from 0.75 and 0.25 mg dry weight of Gac fruit per gram body weight was given daily to Balb/c mice (n=15/group). The water extract inhibited the growth of the colon 26-20 adenocarcinoma cell line, transplanted in Balb/c mice, reducing wet tumor weight by 23.6%. Histological and immunohistochemical results indicated that Gac water extract reduced the density of blood vessels around the carcinoma. The water extract also produced a marked suppression of cell proliferation in colon 26-20 and HepG2 cells. Cell cycle analysis demonstrated a significant accumulation of cells in the S phase by water extract. Immunoblotting showed that cyclin A, Cdk2, p27waf1/Kip1 were down-regulated, whereas the protein level of p21waf1/Cip1 was not decreased. Treatment of colon 26-20 cells with Gac extract induced necrosis rather than apoptosis. The antitumor component was confirmed as a protein with molecular weight of 35 kDa, retained in the water-soluble high molecular weight fraction. Thus, the bioactive antitumor compound in Gac extract is a protein, which is distinct from lycopene, another compound in Gac fruit with potential antitumor activity.
What is Gac Fruit?
Because it has a relatively short harvest season (which peaks in December and January), making it less abundant than other foods, gac is typically served at ceremonial or festive occasions in Vietnam, such as Tết (the Vietnamese new year) and weddings. The fruit has begun to be marketed outside of Asia in the form of juice dietary supplements because of its allegedly high phytonutrient content.
Traditionally, gac has been used as both food and medicine in the regions in which it grows. Other than the use of its fruit and leaves for special Vietnamese culinary dishes, gac is also used for its medicinal and nutritional properties. In Vietnam, the seed membranes are used to aid in the relief of dry eyes, as well as to promote healthy vision. Similarly, in traditional Chinese medicine the seeds of gac, known in Mandarin Chinese as mùbiēzǐ (Chinese: 木鳖子), are employed for a variety of internal and external purposes. Recently, attention is being to be attracted to it in the West, because chemical analysis of the fruit suggests it has high concentrations of several important phytonutrients.
The fruit contains by far the highest content of beta-carotene of any known fruit or vegetable. Research has confirmed that the beta-carotene (vitamin A) in the fruit is highly bioavailable. In a double-blind study with 185 children, some were given a dish containing 3.5 mg beta-carotene from spiny bitter gourd, while others were given an identical-looking dish containing 5 mg beta-carotene powder. After 30 days, the former group eating natural beta-carotene had significantly greater plasma (blood) levels of beta-carotene than the latter with synthetic beta-carotene. This oil also included high levels of vitamin E. The fatty acids in the aril are important for the absorption of fat-soluble nutrients, including carotenoids, in a diet typically low in fat. Thus, gac provides an acceptable source of high levels of valuable antioxidants that have good bioavailability. Also, vitamin A is good for skin and vision.
Gac has been shown to be especially high in lycopene content. Relative to mass, it contains up to 70 times the amount of lycopene found in tomatoes. It has also been found to contain up to 10 times the amount of beta-carotene of carrots or sweet potatoes. Additionally, the carotenoids present in gac are bound to long-chain fatty acids, resulting in what is claimed to be a more bioavailable form. There has also been recent research that suggests that gac contains a protein that may inhibit the proliferation of cancer cells.
Is Gac available in ROMANIA?
YES, it is!