Therapeutic Antiallergy Effect of Fermented Soy Curd by Pediococcus inopinatus Y2

항알레르기에 대한 Pediococcus inopinatus Y2 유산균 발효 두유 커드의 치료 효과

Abstract

The use of fermented soy curd as a functional substance has been actively studied due to the anti-inflammatory and antiallergic activity of soybean protein hydrolyzate by enzymes of lactic acid bacteria. The present study investigated the potential of soy curd as a treatment for atopic dermatitis (AD). Pediococcus inopinatus Y2 (P. inopinatus Y2) lactic acid bacteria were inoculated into soy milk and fermented ($30^{\circ}C$, 24 hr). Changes in body weights, ear thicknesses, IgE concentrations, and weights of immune organs in ICR female mice were quantified. Moderate weight gain occurred in most of the groups. The ear thickness was lowest in the untreated group (no group), and it was allergic and thickened in the phthalic anhydride (PA) treatment group. Based on visual observations, as compared with the skin condition of the PA-induced AD group, the skin condition of the animals in the fermented soy curd (FSC) group was improved. Therefore, FSC by lactic acid bacteria seemed to improve AD. Based on the comparison of the weights of the spleen, thymus, and lymph nodes, as well as the results of the IgE analysis, soy milk, in addition to FSC, had a therapeutic effect. However, the antiallergy effects of FSC in terms of AD were far superior to those of soy milk. These results indicated that FSC can be used as a treatment for AD.

본 실험에서는 Pediococcus inopinatus Y2 (P. inopinatus Y2) 유산균으로 발효시켜 제조한 발효 두유커드가 알레르기성 피부질환의 치료에 미치는 효과를 확인하기 위해 알레르기 유발 ICR 마우스를 대상으로 4주간 경구투여한 이후, 마우스의 체중, 귀 두께, IgE 농도, 면역 기관 중량 및 혈청 IgE 농도 변화를 비교 분석하였다. 대부분의 동물실험 군은 적당한 체중 증가를 보였다. 귀 두께에서, 아무처리를 하지 않은 그룹(No group)이 가장 낮은 두께를 나타냈고, PA 처리 그룹이 알레르기가 유발되어 두꺼워졌다. PA로 유도된 AD 마우스를 육안으로 관찰하였을 때, 발효 두유커드 투여그룹(FSC group)의 피부 상태는 더욱 개선되었다. 이에 따라 유산균에 의한 발효 두유커드가 피부염을 회복시킬 수 있음이 확인되었다. 마우스의 비장과 림프절의 무게와 IgE 농도를 비교 한 결과, 두유를 투여한 그룹(SM group)도 치료 효과를 보였으나 발효 두유커드의 알레르기 치료 효과가 더 우수 하였다. 결과적으로 발효 된 두유커드가 알레르기성 피부질환을 개선 할 수 있음을 확인할 수 있었다.

Fig. 1. Effects of fermented soycurd intake on body weight. Body weights of mice in the five groups were measured with a chemical balance. Soy milk and fermented soycurd were orally administered and PA solution was repeatedly applied to the dorsum of the ICR mice ear. Values are expressed as the Means ± SD (n=7) of 7 independent mice. No significant difference in body weight was detected No group or Ve group after any of the treatments.

Fig. 2. Changes in immune organ weight. Differences in organ weights of ICR mice. After final application, the weights of three organs, including the spleen, and lymph nodes, were measured by following the procedure described in Materials and Methods. (A) The spleen weight were analyzed using a chemical balance. (B) The mandibular lymph node were harvested from the neck regions of the mice using a microscissors and they were weighted using a chemical balance. Differences in mandibular lymph node. The lymph node of mice in the five groups were observed by photo images taken after harvested. Data shown are the means ± SD (n=7) of 7 independent mice. a, p<0.05 is the significance level compared to the No group. b, p<0.05 is the significance level compared to the PA+Vehicle treated group by Tukey's multiple range test.

Fig. 3. Difference in ear thickness. PA solution was repeatedly applied to the dorsum of ears of ICR mice during oral gavage of soymilk and fermented soycurd. After 4 weeks, ear thickness was observed. Data shown are the Means ± SD (n=7) of 7 independent mice. a, p<0.05 is the significance level compared to the No group by Tukey's multiple range test.

Fig. 4. Ear phenotypes. PA solution was repeatedly applied to the dorsum of ears of ICR mice during oral gavage of soymilk (SM) and fermented soycurd (FSC). After 4 weeks, phenotypes were observed. Arrowhead indicates the ear vein and skin inflammation.

Fig. 5. Changes in serum IgE concentration. The serum IgE concentration in ICR mice were analyzed. Serum was collected from the abdominal vein of mice. Serum IgE concentration was quantified by ELISA. Data shown are the Means ± SD (n=7) of 7 independent mice. a, p<0.05 is the significance level compared to the No group. b, p<0.05 is the significance level compared to the PA+Vehicle treated group by Tukey's multiple range test.

Table 1. Differences in immune organ weight