• Asian-Australasian Journal of Animal Sciences
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• 제12권7호
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• pp.1135-1141
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• 1999

A large number of investigations have shown that changes in nutritional condition affect endocrine status in avian species. Herein, recent findings including novel peptides discovered by the development of the techniques in the field of molecular biology have been reviewed. The insulin-like growth factors (IGF-I and IGF-II) found in chickens have been characterized and shown to be 70 and 66 amino acid polypeptides, respectively. Plasma IGF-I level is very responsive to nutrition, Le. varying dietary proteins and energy intakes, and food restriction. Plasma IGF-II concentration is altered by nutritional deprivation to a much smaller extent than plasma IGF-I concentration. Almost all of the serum and tissue IGFs are found in a complex composed of IGF and IGF-binding protein (IGFBP). In the chicken plasma, the major IGFBP differs from that in mammalian plasma. The proglucagon mRNA encodes glucagon and two glucagon-like peptides (GLP-I and GLP-2). The intracerebroventricular administration of GLP-l strongly decreased food intake of chicks, and it was indicated that the inhibition of food intake by GLP-l was associated with neuropeptide Y, which is one of the neurotransmitters reported to enhance food intake.

• 식품과학과 산업
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• 제51권4호
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• pp.302-312
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• 2018

우유 단백질과 같은 식이 단백질은 분해되기 전에는 대사 조절을 위한 생물학적인 활성을 나타내지 않으나 장에서의 소화과정이나 단백질 분해 효소, 또는 미생물 발효 과정을 통하여 저분자의 펩타이드로 분해되어 수용체 결합을 통하여 생체조절기능을 발휘하거나, 체내 대사의 조절에 관여하는 다양한 효소의 활성을 억제함으로써 기능을 발휘하기도 한다. 우유단백질의 섭취에 의한 혈당 감소 효과는 여러 연구자에 의하여 확인되었으며, 그 작용 기전은 주로 분지사슬 아미노산에 의한 인슐린 분비촉진 기전과 음식물의 소화 과정 중 위장관에서 췌장에서 인슐린 분비 촉진, glucagon의 분비를 감소시켜 혈당을 감소시키는 역할을 담당하는 내분비 호르몬의 일종인 GLP-1의 작용에 영향을 미치는 기전을 생각할 수 있다. 생리적 환경에서 GLP-1은 GLP-1을 가수분해하여 불활성화시키는 DPP-4에 의하여 빠르게 분해되어 생물학적 활성을 소실하기 때문에 DPP-4 억제제는 제 2형 당뇨의 새로운 치료 방법으로써 주목을 받고 있다. DPP-4의 억제 효능을 가진 다수의 기능성 펩타이드가 우유단백질의 분해에 의하여 생성됨이 보고되었으며 그 효능이 in vitro 연구는 물론 동물 모델을 이용한 연구에서도 증명되었다. 이상의 연구 결과를 근거로 할 때 우유 단백질 유래 DPP-4 억제 펩타이드는 인체 적용 연구를 통하여 혈당 조절에 도움을 주는 기능성 소재로 개발될 수 있는 충분한 가능성을 가지고 있다고 판단된다.

• 비만대사연구학술지
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• 제1권1호
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• pp.4-13
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• 2022

Currently, pharmacotherapy is becoming essential for obesity, owing to its expanding and increasing epidemiology. In this review, novel peptide-based drugs of four classes are covered: GLP-1 receptor agonist, GIP/GLP-1 receptor dual agonist, glucagon/GLP-1 receptor dual agonist, and a combination of amylin receptor agonist/GLP-1 receptor agonist. Semaglutide is a next-generation GLP-1 receptor agonist with a longer duration and stronger weight and glucose reduction effects than liraglutide and dulaglutide. In the STEP1 trial, semaglutide 2.4 mg reduced body weight by approximately 15% in people with obesity with similar or milder adverse events than liraglutide 3.0 mg. Tirzepatide, a GIP/GLP-1 receptor dual agonist, also has a long duration and strong weight- and glucose-lowering effect. According to SURPASS-2, 3, and 4, in patients with BMI≥25 kg/m² and type 2 diabetes mellitus (T2DM), tirzepatide 15 mg reduced the initial body weight by >13%. Cotadutide, a glucagon/GLP-1 receptor dual agonist, showed weaker weight-lowering effects than semaglutide and tirzepatide, while it was comparable to that of liraglutide in a phase 2 clinical trial for non-alcoholic fatty liver disease in patients with BMI≥25 kg/m² and T2DM. Additionally, its effect on the liver was noticeable. The long-acting amylin receptor agonist cargrilintide combined with semaglutide can be another effective option for obesity treatment. Even in a small phase 1 trial with a short study period of 20 weeks, cargrilintide 2.4 mg/semaglutide 2.4 mg reduced by 17% of initial body weight in people with BMI 27-39.9 kg/m². In coming several years, semaglutide, tirzepatide, and cargrilintide/semaglutide will become available for obesity treatment in Korea.