Anthocyanin-rich tea Sunrouge upregulates expressions of heat shock proteins in the gastrointestinal tract of ICR mice: A comparison with the conventional tea cultivar Yabukita

Abstract

Sunrouge is an anthocyanin-rich, new tea cultivar that contains similar levels of catechins as Yabukita, the most popular tea cultivar consumed in Japan. Interestingly, Sunrouge preparations have previously been shown to have more pronounced acetylcholinesterase inhibitory and anticolitis activities than those of Yabukita. In this study, we examined their effects on expressions of self-defensive molecules, including heat shock proteins (HSPs), which are molecular chaperones involved in homeostasis and longevity. Hot water extract from freeze-dried Sunrouge significantly upregulated messenger RNA (mRNA) expressions of HSP40, HSP70, and HSP32 (heme oxygenase-1), with grades greater than those shown by Yabukita. Oral administration of freeze-dried preparation of Sunrouge to male ICR mice at a dose of 1% in the basal diet for 1 month resulted in marked upregulations of several HSP mRNA expressions in mucosa from the gastrointestinal tract, especially the upper small intestine. Again, its efficacy was remarkably higher than that of Yabukita. Moreover, exposure of Caenorhabditis elegans to Sunrouge conferred thermoresistant phenotype, and also resulted in a significant life-span elongation. Taken together, our results suggest that Sunrouge is a unique and promising tea cultivar for regulating self-defense systems.

Keywords: Sunrouge; anthocyanins; green tea; heat shock protein; self-defense.

Fig. 1

(A) Viability of Hepa1c1c7 mouse hepatoma cells exposed to Yabukita (YK) and Sunrouge (SR) preparations for 6 hours. (B,C) Effects of YK (10%, v/v) and SR (5%, v/v) on messenger RNA expressions of heme oxygenase-1 (HO-1), cystationine β-synthase (CBS), cystationine γ-liase (CSE), and heat shock protein (HSP) as quantified by reverse transcription-polymerase chain reaction analyses. *p < 0.05 (versus non-treated control group), #p < 0.05 (versus YK group) in the Student t test.

Fig. 2

Effects of oral administrations of basal diet (CTL), Yabukita (YK) and Sunrouge (SR) (1%, w/w, in the basal diet for 1 month each) on messenger RNA expression of heat shock protein (HSP) genes and HO-1 in the mucosa of the (A) stomach, (B) upper small intestine, (C) lower small intestine, (D) large intestine, (E) liver, and (F) kidney of ICR mice. Four mice were used for each group. *p < 0.05 (vs. nontreated control group), #p < 0.05 (vs. YK group) in the Student t test.

Fig. 2

Effects of oral administrations of basal diet (CTL), Yabukita (YK) and Sunrouge (SR) (1%, w/w, in the basal diet for 1 month each) on messenger RNA expression of heat shock protein (HSP) genes and HO-1 in the mucosa of the (A) stomach, (B) upper small intestine, (C) lower small intestine, (D) large intestine, (E) liver, and (F) kidney of ICR mice. Four mice were used for each group. *p < 0.05 (vs. nontreated control group), #p < 0.05 (vs. YK group) in the Student t test.

Fig. 2

Effects of oral administrations of basal diet (CTL), Yabukita (YK) and Sunrouge (SR) (1%, w/w, in the basal diet for 1 month each) on messenger RNA expression of heat shock protein (HSP) genes and HO-1 in the mucosa of the (A) stomach, (B) upper small intestine, (C) lower small intestine, (D) large intestine, (E) liver, and (F) kidney of ICR mice. Four mice were used for each group. *p < 0.05 (vs. nontreated control group), #p < 0.05 (vs. YK group) in the Student t test.

Fig. 3

Effects of oral Yabukita (YK, 0.008-20%, v/v) and Sunrouge (SR, 0.0016-10%, v/v) on the motility of Caenorhabditis elegans and mild heat training. The age-synchronized Day 4 worms were incubated at 20°C for 1 hour in S-basal buffer containing tea samples, then subjected to heat shock at 37°C for 30 minutes. Mild heat training at 33°C for 1 hour served as a positive control. Twenty-four hours after each treatment, the motility of the worms was evaluated by counting the bending numbers per minute. Each experiment was done in triplicate, and the motility of five or more worms were counted. *p < 0.05 (versus NT), **p < 0.05 (versus CTL) in the Student t test. CTL = heat shock group (37°C for 30 minutes); HT = heat training group (33°C for 1 hour); NT = nontreated group.

Fig. 4

Sunrouge (SR, 0.2 or 1%, v/v), but not Yabukita (YK, 1 or 5%, v/v), significantly extended life-span of Caenorhabditis elegans. Solid line with closed circles = nontreated control; unbroken line with open squares = 1% YK; unbroken line with open triangles = 5% YK; broken line with open squares = 0.2% SR; broken line with open triangles = 1% SR. Both 0.2% and 1% SR, but not YK, showed significant longevity extension versus nontreated control by Wilcoxon test (p < 0.05).