Selective anti-proliferative activities of Carica papaya leaf juice extracts against prostate cancer.

BACKGROUND: Prostate cancer (PCa) is the leading cause of cancer related deaths in men. Carica papaya is a popular tropical plant that has been traditionally used for its nutritional and medicinal properties. METHODS: We investigated the anti-proliferative responses of papaya leaf juice (LJP) and its various extracts ("biological"- in vitro digested, "physical"- size exclusion, and "chemical"-solvent extraction) on a range of cell lines representing benign hyperplasia, tumorigenic and normal cells of prostate origin. RESULTS: Time course analysis (by 24h, 48h and 72h) of LJP (1-0.1mg/mL) before and after in vitro digestion, and of molecular weight based fractions of LJP showed anti-proliferative responses. The medium polarity fraction of LJP (0.03-0.003mg/mL) after 72h exposure showed potent growth inhibitory (IC50=0.02-0.07mg/mL) and cytotoxic activities on all prostate cells, with the exception of the normal (RWPE-1 and WPMY-1) cells. Flow cytometry analysis showed S phase cell cycle arrest and apoptosis as a possible mechanism for these activities. Medium polar fraction of LJP also inhibited migration and adhesion of metastatic PC-3 cells. CONCLUSION: This is the first report suggesting selective anti-proliferative and anti-metastatic attributes of LJP extract against prostatic diseases, including PCa.

Anti-inflammatory and immunomodulatory properties of Carica papaya.

Chronic inflammation is linked with the generation and progression of various diseases such as cancer, diabetes and atherosclerosis, and anti-inflammatory drugs therefore have the potential to assist in the treatment of these conditions. Carica papaya is a tropical plant that is traditionally used in the treatment of various ailments including inflammatory conditions. A literature search was conducted by using the keywords "papaya", "anti-inflammatory and inflammation" and "immunomodulation and immune" along with cross-referencing. Both in vitro and in vivo investigation studies were included. This is a review of all studies published since 2000 on the anti-inflammatory activity of papaya extracts and their effects on various immune-inflammatory mediators. Studies on the anti-inflammatory activities of recognized phytochemicals present in papaya are also included. Although in vitro and in vivo studies have shown that papaya extracts and papaya-associated phytochemicals possess anti-inflammatory and immunomodulatory properties, clinical studies are lacking.

Traditional Aboriginal Preparation Alters the Chemical Profile of Carica papaya Leaves and Impacts on Cytotoxicity towards Human Squamous Cell Carcinoma.

Carica papaya leaf decoction, an Australian Aboriginal remedy, has been used widely for its healing capabilities against cancer, with numerous anecdotal reports. In this study we investigated its in vitro cytotoxicity on human squamous cell carcinoma cells followed by metabolomic profiling of Carica papaya leaf decoction and leaf juice/brewed leaf juice to determine the effects imparted by the long heating process typical of the Aboriginal remedy preparation. MTT assay results showed that in comparison with the decoction, the leaf juice not only exhibited a stronger cytotoxic effect on SCC25 cancer cells, but also produced a significant cancer-selective effect as shown by tests on non-cancerous human keratinocyte HaCaT cells. Furthermore, evidence from testing brewed leaf juice on these two cell lines suggested that the brewing process markedly reduced the selective effect of Carica papaya leaf on SCC25 cancer cells. To tentatively identify the compounds that contribute to the distinct selective anticancer activity of leaf juice, an untargeted metabolomic approach employing Ultra High Performance Liquid Chromatography-Quadrupole Time of Flight-Mass Spectrometry followed by multivariate data analysis was applied. Some 90 and 104 peaks in positive and negative mode respectively were selected as discriminatory features from the chemical profile of leaf juice and >1500 putative compound IDs were obtained via database searching. Direct comparison of chromatographic and tandem mass spectral data to available reference compounds confirmed one feature as a match with its proposed authentic standard, namely pheophorbide A. However, despite pheophorbide A exhibiting cytotoxic activity on SCC25 cancer cells, it did not prove to be the compound contributing principally to the selective activity of leaf juice. With promising results suggesting stronger and more selective anticancer effects when compared to the Aboriginal remedy, Carica papaya leaf juice warrants further study to explore its activity on other cancer cell lines, as well as investigation to confirm the identity of compounds contributing to its selective effect, particularly those compounds altered by the long heating process applied during the traditional Aboriginal remedy preparation.

Chemical Characterization and in Vitro Cytotoxicity on Squamous Cell Carcinoma Cells of Carica papaya Leaf Extracts.

In traditional medicine, Carica papaya leaf has been used for a wide range of therapeutic applications including skin diseases and cancer. In this study, we investigated the in vitro cytotoxicity of aqueous and ethanolic extracts of Carica papaya leaves on the human oral squamous cell carcinoma SCC25 cell line in parallel with non-cancerous human keratinocyte HaCaT cells. Two out of four extracts showed a significantly selective effect towards the cancer cells and were found to contain high levels of phenolic and flavonoid compounds. The chromatographic and mass spectrometric profiles of the extracts obtained with Ultra High Performance Liquid Chromatography-Quadrupole Time of Flight-Mass Spectrometry were used to tentatively identify the bioactive compounds using comparative analysis. The principal compounds identified were flavonoids or flavonoid glycosides, particularly compounds from the kaempferol and quercetin families, of which several have previously been reported to possess anticancer activities. These results confirm that papaya leaf is a potential source of anticancer compounds and warrant further scientific investigation to validate the traditional use of papaya leaf to treat cancer.

Simultaneous quantitative analysis of eight vitamin D analogues in milk using liquid chromatography-tandem mass spectrometry.

Milk is an important source of nutrients for various risk populations, including infants. The accurate measurement of vitamin D in milk is necessary to provide adequate supplementation advice for risk groups and to monitor regulatory compliance. Currently used liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods are capable of measuring only four analogues of vitamin D in unfortified milk. We report here an accurate quantitative analytical method for eight analogues of vitamin D: Vitamin D2 and D3 (D2 and D3), 25-hydroxy D2 and D3, 24,25-dihydroxy D2 and D3, and 1,25-dihydroxyD2 and D3. In this study, we compared saponification and protein precipitation for the extraction of vitamin D from milk and found the latter to be more effective. We also optimised the pre-column derivatisation using 4-phenyl-l,2,4-triazoline-3,5-dione (PTAD), to achieve the highest sensitivity and accuracy for all major vitamin D forms in milk. Chromatography was optimised to reduce matrix effects such as ion-suppression, and the matrix effects were eliminated using co-eluting stable isotope labelled internal standards for the calibration of each analogue. The analogues, 25-hydroxyD3 (25(OH)D3) and its epimer (3-epi-25(OH)D3) were chromatographically resolved, to prevent over-estimation of 25(OH)D3. The method was validated and subsequently applied for the measurement of total vitamin D levels in human, cow, mare, goat and sheep milk samples. The detection limits, repeatability standard deviations, and recovery ranges were from 0.2 to 0.4 femtomols, 6.30-13.5%, and 88.2-105%, respectively.

Review of procedures used for the extraction of anti-cancer compounds from tropical plants.

Tropical plants are important sources of anti-cancer lead molecules. According to the US National Cancer Institute, out of the 3000 plants identified as active against cancer using in vitro studies, 70% are of tropical origin. The extraction of bioactive compounds from the plant materials is a fundamental step whose efficiency is critical for the success of drug discovery efforts. There has been no review published of the extraction procedures of anti-cancer compounds from tropical plants and hence the following is a critical evaluation of such procedures undertaken prior to the use of these compounds in cancer cell line studies, during the last five years. It presents a comprehensive analysis of all approaches taken to extract anti-cancer compounds from various tropical plants. (Databases searched were PubMed, SciFinder, Web of Knowledge, Scopus, Embase and Google Scholar).

Two peptides, cycloaspeptide A and nazumamide A from a sponge associated marine actinobacterium Salinispora sp.

Marine sponges are a major component of benthic communities and act as a reservoir for microbial species. In terms of biomass, they are the richest source of secondary metabolite production, with the potential to influence both benthic and pelagic systems. In most cases it is the sponge-associated microbes that account for many of the secondary metabolites assigned to the host. Here we report the occurrence of cycloaspeptide A, a fungus-derived cyclic peptide, in a culturable bacterium Salinispora arenicola. We have also identified nazumamide A, a sponge-derived linear tetrapeptide currently used as a thrombin inhibitor, in Salinispora pacifica. Their structures were determined using an integrated approach consisting of: (1) HPLC-UV-Vis-QToF-MS analysis with multimode ionization (ESI and APCI) and fast polarity switching; (2) database searching and matching of monoisotopic masses, retention times, mass spectra of the precursor and product ions of the compounds of interest and the authentic reference standards thereof.

Anticancer activity of Carica papaya: a review.

Carica papaya is widely cultivated in tropical and subtropical countries and is used as food as well as traditional medicine to treat a range of diseases. Increasing anecdotal reports of its effects in cancer treatment and prevention, with many successful cases, have warranted that these pharmacological properties be scientifically validated. A bibliographic search was conducted using the key words "papaya", "anticancer", and "antitumor" along with cross-referencing. No clinical or animal cancer studies were identified and only seven in vitro cell-culture-based studies were reported; these indicate that C. papaya extracts may alter the growth of several types of cancer cell lines. However, many studies focused on specific compounds in papaya and reported bioactivity including anticancer effects. This review summarizes the results of extract-based or specific compound-based investigations and emphasizes the aspects that warrant future research to explore the bioactives in C. papaya for their anticancer activities.

Bioactivity of mango flesh and peel extracts on peroxisome proliferator-activated receptor γ [PPARγ] activation and MCF-7 cell proliferation: fraction and fruit variability.

Mangos are a source of bioactive compounds with potential health promoting activity. Biological activities associated with mango fractions were assessed in cell-based assays to develop effective extraction and fractionation methodologies and to define sources of variability. Two techniques were developed for extraction and fractionation of mango fruit peel and flesh. Liquid chromatography-mass spectrometry (LC-MS) was used to assess compositional differences between mango fractions in flesh extracts. Many of the extracts were effective in inhibiting the proliferation of human breast cancer cells in vitro. All fractions showed bioactivity in PPAR activation assays, but quantitative responses showed marked fruit-to-fruit variability, highlighting the need to bulk fruit prior to extraction for activity-guided fractionation of bioactive components. This study also suggests that combinations of diverse molecular components may be responsible for cell-level bioactivities from mango fractions, and that purification and activity profiling of individual components may be difficult to relate to whole fruit effects. Practical Application: Although the health benefits of fruits are strongly indicated from studies of diet and disease, it is not known what role individual fruit types can play, particularly for tropical fruits. This study shows that there is a diversity of potentially beneficial bioactivities within the flesh and peel of mango fruit, although fruit-to-fruit variation can be large. The results add to the evidence that the food approach of eating all components of fruits is likely to be more beneficial to health than consuming refined extracts, as the purification process would inevitably remove components with beneficial bioactivities.

Mango extracts and the mango component mangiferin promote endothelial cell migration.

This study tested the hypothesis that mango extracts contain bioactive molecules capable of modulating endothelial cell migration, an essential step in the formation of new blood vessels or angiogenesis. The formation of new blood vessels is an important therapeutic target for diseases such as limb ischemia, coronary infarction or stroke. We examined the effect of mango peel and flesh extracts as well as the individual polyphenolic molecules, mangiferin and quercetin, on bovine aortic cell migration using a modified Boyden chamber assay. Our results show that mangiferin, and extracts rich in mangiferin, increase endothelial cell migration. The dose-effect relationship for various extracts further suggests that this action of mangiferin is modulated by other components present in the extracts. The promigratory effect of mango extracts or mangiferin was unrelated to an effect on cell proliferation, and did not involve a change in the production of matrix metalloprotease-2 or -9 by the endothelial cells. Taken together, these results suggest that mangiferin present in mango extracts may have health promoting effects in diseases related to the impaired formation of new blood vessels.