Biochemical characterisation of a Kunitz-type inhibitor from Tamarindus indica L. seeds and its efficacy in reducing plasma leptin in an experimental model of obesity

Amanda Fernandes de Medeiros; Izael de Sousa Costa; Fabiana Maria Coimbra de Carvalho; Sumika Kiyota; Beatriz Blenda Pinheiro de Souza; Daniel Nogoceke Sifuentes; Raphael Paschoal Serquiz; Bruna Leal Lima Maciel; Adriana Ferreira Uchôa; Elizeu Antunes Dos Santos; Ana Heloneida de Araújo Morais

doi:10.1080/14756366.2017.1419220

Biochemical characterisation of a Kunitz-type inhibitor from Tamarindus indica L. seeds and its efficacy in reducing plasma leptin in an experimental model of obesity

J Enzyme Inhib Med Chem. 2018 Dec;33(1):334-348. doi: 10.1080/14756366.2017.1419220.

Authors

Amanda Fernandes de Medeiros¹, Izael de Sousa Costa¹, Fabiana Maria Coimbra de Carvalho¹, Sumika Kiyota², Beatriz Blenda Pinheiro de Souza^{3

4}, Daniel Nogoceke Sifuentes⁴, Raphael Paschoal Serquiz¹, Bruna Leal Lima Maciel^{5

6}, Adriana Ferreira Uchôa^{1

7}, Elizeu Antunes Dos Santos^{1

8}, Ana Heloneida de Araújo Morais^{1

5

6}

Affiliations

¹ a Postgraduate Biochemistry Program, Biosciences Center , Federal University of Rio Grande do Norte , Natal , Brazil.
² b Laboratory of Protein and Peptide Biochemistry , CPDSA, Biological Institute , São Paulo , Brazil.
³ c Postgraduate Biological Molecular, Institute of Biological Sciences , University of Brasília , Distrito Federal , Brasília , Brazil.
⁴ d Embrapa Genetic Resources and Biotechnology , Embrapa , Distrito Federal , Brasília , Brazil.
⁵ e Postgraduate Nutrition Program, Center for Health Sciences , Federal University of Rio Grande do Norte , Natal , Brazil.
⁶ f Department of Nutrition, Center for Health Sciences , Federal University of Rio Grande do Norte , Natal , Brazil.
⁷ g Department of Cell Biology and Genetics, Biosciences Center , Federal University of Rio Grande do Norte , Natal , Brazil.
⁸ h Department of Biochemistry, Biosciences Center , Federal University of Rio Grande do Norte , Natal , Brazil.

Abstract

A trypsin inhibitor isolated from tamarind seed (TTI) has satietogenic effects in animals, increasing the cholecystokinin (CCK) in eutrophy and reducing leptin in obesity. We purified TTI (pTTI), characterised, and observed its effect upon CCK and leptin in obese Wistar rats. By HPLC, and after amplification of resolution, two protein fractions were observed: Fr1 and Fr2, with average mass of [M + 14H]⁺ = 19,594,690 Da and [M + 13H]⁺ = 19,578,266 Da, respectively. The protein fractions showed 54 and 53 amino acid residues with the same sequence. pTTI presented resistance to temperature and pH variations; IC₅₀ was 2.7 × 10^-10mol.L^-1 and Ki was 2.9 × 10^-11mol.L^-1. The 2-DE revealed spots with isoelectric points between pH 5 and 6, and one near pH 8. pTTI action on leptin decrease was confirmed. We conclude that pTTI is a Kunitz trypsin inhibitor with possible biotechnological health-related application.

Keywords: CCK; Tamarind; Wistar rats; antitryptic.

MeSH terms

Animals
Anti-Obesity Agents / chemistry
Anti-Obesity Agents / isolation & purification
Anti-Obesity Agents / pharmacology*
Disease Models, Animal*
Dose-Response Relationship, Drug
Leptin / blood*
Male
Obesity / blood*
Obesity / drug therapy*
Obesity / metabolism
Peptides / chemistry
Peptides / isolation & purification
Peptides / pharmacology*
Plant Proteins / chemistry
Plant Proteins / isolation & purification
Plant Proteins / pharmacology*
Rats
Rats, Wistar
Seeds / chemistry
Structure-Activity Relationship
Tamarindus / chemistry*
Trypsin / metabolism

Substances

Anti-Obesity Agents
Kunitz-type protease inhibitor, plant
Leptin
Peptides
Plant Proteins
Trypsin

Grants and funding

This work received the financial support of the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), the Conselho Nacional de Desenvolvimento Cientítico e Tecnológico (CNPq) (scholarship) and Fundação de Apoio à Pesquisa do Rio Grande do Norte (FAPERN) Brazilian research supporting agencies [FAPERN/CAPES 006/2014].