Article

Inhibition of prostate cancer cell growth by an avocado extract: Role of lipid-soluble bioactive substances

Center for Human Nutrition, David Geffen School of Medicine, University of California, Los Angeles, CA 90095-1742, USA.
The Journal of Nutritional Biochemistry (Impact Factor: 4.59). 02/2005; 16(1):23-30. DOI: 10.1016/j.jnutbio.2004.08.003
Source: PubMed

ABSTRACT Although the avocado is known as a rich source of monounsaturated fatty acids, there has been far less attention given to its content of other bioactive substances including carotenoids, which might contribute to cancer preventive properties similar to those attributed to other fruits and vegetables. The yellow-green color of the avocado prompted us to study the carotenoid content of this fruit using established methods in our laboratory. The California Hass avocado (Persea americana Mill.) was selected for study, because it is the most commonly consumed variety in the southwest United States. These avocados were found to contain the highest content of lutein among commonly eaten fruits as well as measurable amounts of related carotenoids (zeaxanthin, alpha-carotene, and beta-carotene). Lutein accounted for 70% of the measured carotenoids, and the avocado also contained significant quantities of vitamin E. An acetone extract of avocado containing these carotenoids and tocopherols was shown to inhibit the growth of both androgen-dependent (LNCaP) and androgen-independent (PC-3) prostate cancer cell lines in vitro. Incubation of PC-3 cells with the avocado extract led to G(2)/M cell cycle arrest accompanied by an increase in p27 protein expression. Lutein alone did not reproduce the effects of the avocado extract on cancer cell proliferation. In common with other colorful fruits and vegetables, the avocado contains numerous bioactive carotenoids. Because the avocado also contains a significant amount of monounsaturated fat, these bioactive carotenoids are likely to be absorbed into the bloodstream, where in combination with other diet-derived phytochemicals they may contribute to the significant cancer risk reduction associated with a diet of fruits and vegetables.

Download full-text

Full-text

Available from: Sergio Huerta, Jul 30, 2015
2 Followers
 · 
373 Views
  • Source
    • "Avocados are rich in unsaturated fatty acids, folic acid, dietary fiber, vitamins, pantothenic acid, and other nutrients [1]. Lipophilic extract of avocado has been revealed be potent in lowering risk of cardiovascular and diabetes, attenuating liver injury, inhibiting prostate cancer cell growth, and inducing apoptosis in human breast cancer cells [2] [3] [4] [5]. The consumption of avocado in United States has increased in recent years, and it amounted up to 740,000 t in 2013. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Phospholipids possess important physiological, structural and nutritional functions in biological systems. This study described a solid-phase extraction (SPE) method, employing graphene and titanium dioxide (G/TiO2) nanocomposite as sorbent, for the selective isolation and enrichment of phospholipids from avocado (Persea americana Mill.). Based on the principal that the phosphoryl group in the phospholipid can interact with TiO2 via a bridging bidentate mode, an optimum condition was established for SPE, and was successfully applied to prepare avocado samples. The extracts were monitored by matrix-assisted laser desorption ionization tim-of-flight/tandem mass spectrometry (MALDI-TOF/MS) in both positive-ion and negative-ion modes. Results showed that phospholipids could be efficiently extracted in a clean manner by G/TiO2 based SPE. In addition, the signals of phospholipids were enhanced while the noise was reduced. Some minor peaks became more obvious. In conclusion, the nanocomposite material of G/TiO2 was proved to be a promising sorbent for selective separation of phospholipids from crude lipid extract.
    Analytica Chimica Acta 12/2014; 852. DOI:10.1016/j.aca.2014.09.022 · 4.52 Impact Factor
  • Source
    • "There are no direct avocado breast cancer clinical studies. Exploratory studies in prostate cancer cell lines suggest antiproliferative and antitumor effects of avocado lipid extracts (Lu et al., 2005). Lutein is one of the active components identified. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Hass avocados, the most common commercial avocado cultivars in the world, contain a variety of essential nutrients and important phytochemicals. Although the official avocado serving is one-fifth of a fruit (30 g), according to NHANES analysis the average consumption is one-half an avocado (68 g), which provides a nutrient and phytochemical dense food consisting of the following: dietary fiber (4.6 g), total sugar (0.2 g), potassium (345 mg), sodium (5.5 mg), magnesium (19.5 mg), vitamin A (43 μg), vitamin C (6.0 mg), vitamin E (1.3 mg), vitamin K1 (14 μg), folate (60 mg), vitamin B-6 (0.2 mg), niacin (1.3 mg), pantothenic acid (1.0 mg), riboflavin (0.1 mg), choline (10 mg), lutein/zeaxanthin (185 μg), phytosterols (57 mg), and high-monounsaturated fatty acids (6.7 g) and 114 kcals or 1.7 kcal/g. The avocado oil consists of 71% monounsaturated fatty acids (MUFA), 13% polyunsaturated fatty acids (PUFA), and 16% saturated fatty acids (SFA), which helps to promote healthy blood lipid profiles and enhance the bioavailability of fat soluble vitamins and phytochemicals from the avocado or other fruits and vegetables, naturally low in fat, which are consumed with avocados. There are eight preliminary clinical studies showing that avocado consumption helps support cardiovascular health. Exploratory studies suggest that avocados may support weight management and healthy aging.
    Critical reviews in food science and nutrition 05/2013; 53(7):738-50. DOI:10.1080/10408398.2011.556759 · 5.55 Impact Factor
  • Source
    • "In support of this hypothesis, it is important to note that in a study (Lu et al. 2005), it was recognized that the use of individual components of avocado like lutein may not be as effective to produce biological effects as it does an avocado extract containing a mixture of lipid-soluble antioxidants with lutein being the main component of such extract. Consequently, it was proposed that the interaction between several lipidic compounds from avocado along with improvement in its bioavailability due to the high content of monounsaturated fats may contribute to the probable beneficial effects of avocado (Lu et al. 2005). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Impaired complex III activity and reactive oxygen species (ROS) generation in mitochondria have been identified as key events leading to renal damage during diabetes. Due to its high content of oleic acid and antioxidants, we aimed to test whether avocado oil may attenuate the alterations in electron transfer at complex III induced by diabetes by a mechanism related with increased resistance to lipid peroxidation. 90 days of avocado oil administration prevented the impairment in succinate-cytochrome c oxidoreductase activity caused by streptozotocin-induced diabetes in kidney mitochondria. This was associated with a protection against decreased electron transfer through high potential chain in complex III related to cytochromes c + c 1 loss. During Fe2+-induced oxidative stress, avocado oil improved the activities of complexes II and III and enhanced the protection conferred by a lipophilic antioxidant against damage by Fe2+. Avocado oil also decreased ROS generation in Fe2+-damaged mitochondria. Alterations in the ratio of C20:4/C18:2 fatty acids were observed in mitochondria from diabetic animals that not were corrected by avocado oil treatment, which yielded lower peroxidizability indexes only in diabetic mitochondria although avocado oil caused an augment in the total content of monounsaturated fatty acids. Moreover, a protective effect of avocado oil against lipid peroxidation was observed consistently only in control mitochondria. Since the beneficial effects of avocado oil in diabetic mitochondria were not related to increased resistance to lipid peroxidation, these effects were discussed in terms of the antioxidant activity of both C18:1 and the carotenoids reported to be contained in avocado oil.
    Journal of Bioenergetics 02/2013; 45(3). DOI:10.1007/s10863-013-9502-3 · 2.71 Impact Factor
Show more