Analysis of Anthocyanins in Dietary Supplements Containing Blueberry Extract

Ishikawa, Fusako; Oishi, Mitsuo; Shindo, Tetsuya; Horie, Masao; Yasui, Akiko; Nakazato, Mitsuo

doi:10.3358/shokueishi.49.339

Cited by 6 publications

(2 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We next attempted to examine if various polyphenols obtained from bilberry had any direct effects on GroES amyloid fibril formation. Bilberry is a rich source of natural polyphenols, and bilberry extracts are mainly composed of glycoside forms of various anthocyanins and a minor fraction of basic skeletal anthocyanidins that are detectable by HPLC and mass analysis. , Figure shows the structures of delphinidin, cyanidin, del 3-gal, and cya 3-gal used in this study. These delphinidin-based and cyanidin-based polyphenols are relatively abundant in VMA.…”

Section: Resultsmentioning

confidence: 99%

Bilberry Anthocyanins Neutralize the Cytotoxicity of Co-Chaperonin GroES Fibrillation Intermediates

Iwasa¹,

Kubo²,

Fukui³

et al. 2013

Biochemistry

View full text Add to dashboard Cite

The co-chaperonin GroES (Hsp10) works with chaperonin GroEL (Hsp60) to facilitate the folding reactions of various substrate proteins. Upon forming a specific disordered state in guanidine hydrochloride, GroES is able to self-assemble into amyloid fibrils similar to those observed in various neurodegenerative diseases. GroES therefore is a suitable model system to understand the mechanism of amyloid fibril formation. Here, we determined the cytotoxicity of intermediate GroES species formed during fibrillation. We found that neuronal cell death was provoked by soluble intermediate aggregates of GroES, rather than mature fibrils. The data suggest that amyloid fibril formation and its associated toxicity toward cell might be an inherent property of proteins irrespective of their correlation with specific diseases. Furthermore, with the presence of anthocyanins that are abundant in bilberry, we could inhibit both fibril formation and the toxicity of intermediates. Addition of bilberry anthocyanins dissolved the toxic intermediates and fibrils, and the toxicity of the intermediates was thus neutralized. Our results suggest that anthocyanins may display a general and potent inhibitory effect on the amyloid fibril formation of various conformational disease-causing proteins.

show abstract

Section: Resultsmentioning

confidence: 99%

Bilberry Anthocyanins Neutralize the Cytotoxicity of Co-Chaperonin GroES Fibrillation Intermediates

Iwasa¹,

Kubo²,

Fukui³

et al. 2013

Biochemistry

View full text Add to dashboard Cite

show abstract

“…Twenty compounds, 15 anthocyanins and 5 anthocyanidins, in bilberry extracts are separable by HPLC analysis with gradient elution using formic acid and methanol‐acetonitrile as the mobile phase (Ishikawa and others 2008). In the present study, we detected 20 compounds in Bilberon‐25 by HPLC and demonstrated that Bilberon‐25, an anthocyanin‐rich extract, was degraded in a time‐dependent manner to an anthocyanidin‐rich compound by heating.…”

Section: Discussionmentioning

confidence: 99%

Anthocyanins, but not Anthocyanidins, from Bilberry (Vaccinium myrtillus L.) Alleviate Pruritus via Inhibition of Mast Cell Degranulation

Yamaura

Ishiwatari

Yamamoto

et al. 2012

Journal of Food Science

View full text Add to dashboard Cite

We have previously reported that bilberry anthocyanins exhibit an anti-pruritic effect in a mouse model of allergic contact dermatitis. It has been reported that anthocyanins are particularly sensitive to thermal treatment and are easily hydrolyzed to anthocyanidins when exposed to high temperatures. The objective of this study was to compare the anti-pruritic effect of anthocyanin-rich quality-controlled bilberry extract and anthocyanidin-rich degraded extract using a mouse model of allergic contact dermatitis. BALB/c mice with allergic contact dermatitis induced by 4 weeks of repeated application of 2,4,6-trinitro-1-chlorobenzene (TNCB) were administered Bilberon-25 orally for 4 weeks after sensitization with TNCB. The effect of Bilberon-25 on pruritus was evaluated by measurement of scratching behavior. RBL-2H3 mast cells were used to investigate the effect of Bilberon-25 on degranulation in 48/80-stimulated mast cells. Compared with nonheated Bilberon-25, the proportion of anthocyanins in heated Bilberon-25 decreased, and the proportion of anthocyanidins was increased in heated-time dependent manner. Treatment with non-heated Bilberon-25 significantly attenuated the TNCB-induced increase in scratching behavior, whereas treatment with 2 h-heated Bilberon-25 did not. Moreover, 300 μg/mL nonheated Bilberon-25 showed significant inhibition of degranulation in RBL-2H3 mast cells, whereas 2 h-heated Bilberon-25 had no effect at any concentration studied. It is assumed that the inhibitory effect of bilberry anthocyanins on pruritus might be mediated, at least in part, by its inhibitory effect on mast cell degranulation. In conclusion, the anthocyanin-rich but not anthocyanidin-rich bilberry extract may be a useful dietary supplement for skin diseases involving pruritic symptoms, such as chronic allergic contact dermatitis, atopic dermatitis, and rhinitis.

show abstract