beta-Cryptoxanthin

International journal of molecular medicine, 2005, 15(4):675-681.

beta-Cryptoxanthin stimulates cell proliferation and transcriptional activity in osteoblastic MC3T3-E1 cells.[Reference: WebLink]

The carotenoid beta-Cryptoxanthin has been shown to have a stimulatory effect on bone formation in rat bone tissues in vitro. The effect of beta-Cryptoxanthin in osteoblastic cells in vitro was investigated.
METHODS AND RESULTS:
Osteoblastic MC3T3-E1 cells were cultured for 72 h in alpha-minimal essential medium containing 10% fetal bovine sereum (FBS) to reach subconfluent monolayers. After culture, the medium was changed, then beta-Cryptoxanthin (10(-8) to 10(-6) M) was added in the culture medium without FBS, and the cells were cultured for an additional 24, 48, or 72 h. The proliferation of osteoblastic cells was significantly enhanced in the presence of beta-Cryptoxanthin (10(-8) to 10(-6) M), when it was cultured for 48 or 72 h in medium containing 10% FBS. When osteoblastic cells with subconfluency were cultured for 48 or 72 h in FBS free-medium containing beta-Cryptoxanthin (10(-8) to 10(-6) M), alkaline phosphatase activity or deoxyribonucleic acid (DNA) content in the cells was significantly increased. Also, protein content in the cells was significantly increased by culture with 10(-6) M beta-Cryptoxanthin for 48 or 72 h. The effect of beta-Cryptoxanthin (10(-6) M) in increasing protein content, alkaline phosphatase activity, or DNA content in the cells was significantly blocked in the presence of staurosporine (10(-6) M) or PD98059 (10(-6) M), which is an inhibitor of protein kinases. The stimulatory effect of beta-Cryptoxanthin (10(-6) M) on cellular biochemical components was completely prevented in the presence of cycloheximide (10(-6) M), an inhibitor of protein synthesis, or 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB; 10(-9) M), an inhibitor of transcriptional activity. The expressions of insulin-like growth factor (IGF)-I and transforming growth factor (TGF)-beta1 mRNAs were demonstrated by reverse transcription-polymerase chain reaction (RT-PCR) analysis in osteoblastic cells using mouse IGF-I or TGF-beta1-specific primers. These expressions were significantly raised in the presence of beta-Cryptoxanthin (10(-6) M).
CONCLUSIONS:
This study demonstrates that beta-Cryptoxanthin has a stimulatory effect on cell proliferation and biochemical components in osteoclastic MC3T3-E1 cells, and that the carotenoid can stimulate transcriptional activity in the cells.

British Journal of Nutrition, 2008,10(4):786-793.

β-Cryptoxanthin from supplements or carotenoid-enhanced maize maintains liver vitamin A in Mongolian gerbils (Meriones unguiculatus) better than or equal to β-carotene supplements.[Reference: WebLink]

Maize with enhanced provitamin A carotenoids (biofortified), accomplished through conventional plant breeding, maintains vitamin A (VA) status in Mongolian gerbils (Meriones unguiculatus).
METHODS AND RESULTS:
Two studies in gerbils compared the VA value of beta-Cryptoxanthin with β-carotene. Study 1 (n 47) examined oil supplements and study 2 (n 46) used maize with enhanced β-cryptoxanthin and β-carotene. After 4 weeks' depletion, seven or six gerbils were killed; remaining gerbils were placed into weight-matched groups of 10. In study 1, daily supplements were cottonseed oil, and 35, 35 or 17·5 nmol VA (retinyl acetate), β-cryptoxanthin or β-carotene, respectively, for 3 weeks. In study 2, one group of gerbils was fed a 50 % biofortified maize diet which contained 2·9 nmol β-cryptoxanthin and 3·2 nmol β-carotene/g feed. Other groups were given equivalent β-carotene or VA supplements based on prior-day intake from the biofortified maize or oil only for 4 weeks. In study 1, liver retinol was higher in the VA (0·74 (sd 0·11) μmol) and beta-Cryptoxanthin (0·65 (sd 0·10) μmol) groups than in the β-carotene (0·49 (sd 0·13) μmol) and control (0·41 (sd 0·16) μmol) groups (P < 0·05). In study 2, the VA (1·17 (sd 0·19) μmol) and maize (0·71 (sd 0·18) μmol) groups had higher liver retinol than the control (0·42 (sd 0·16) μmol) group (P < 0·05), whereas the β-carotene (0·57 (sd 0·21) μmol) group did not.
CONCLUSIONS:
Bioconversion factors (i.e. 2·74 μg beta-Cryptoxanthin and 2·4 μg β-carotene equivalents in maize to 1 μg retinol) were lower than the Institute of Medicine values.

Archives of biochemistry & biophysics, 1995, 324(2):385.

beta-Cryptoxanthin selectively increases in human chylomicrons upon ingestion of tangerine concentrate rich in beta-cryptoxanthin esters.[Reference: WebLink]

beta-Cryptoxanthin is a major source of vitamin A, often second only to beta-carotene, and is present in fruits such as oranges, tangerines, and papayas.
METHODS AND RESULTS:
Here, we studied the uptake of this carotenoid upon ingestion of tangerine juice concentrate, rich in beta-Cryptoxanthin esters. Increasing amounts of free beta-Cryptoxanthin were detected in chylomicrons and serum. Peak levels in chylomicrons were reached at t = 6 h, and the concentration returned toward basal levels at t = 9 h. No beta-Cryptoxanthin esters were detected in chylomicrons or serum, indicating efficient cleavage in the intestine before the carotenoid is incorporated into lipoproteins by the liver. Other xanthophyll esters, e.g., of zeaxanthin and lutein, were present in low amounts in the tangerine concentrate.
CONCLUSIONS:
As with beta-Cryptoxanthin, no esters appeared in serum or chylomicrons, suggesting that the cleavage of carotenoid esters prior to release into the lymphatic circulation occurs generally in human oxocarotenoid biokinetics.