Alexandre Coelho Serquiz

Supplementation with a new trypsin inhibitor from peanut is associated with reduced fasting glucose, weight control, and increased plasma CCK secretion in an animal model

Abstract Ingestion of peanuts may have a beneficial effect on weight control, possibly due to the satietogenic action of trypsin inhibitors. The aim of this study was to isolate a new trypsin inhibitor in a typical Brazilian peanut sweet (paçoca) and evaluate its effect in biochemical parameters, weight gain and food intake in male Wistar rats. The trypsin inhibitor in peanut paçoca (AHTI) was isolated. Experimental diets were prepared with AIN-93G supplemented with AHTI. Animals had their weight and food intake monitored. Animals were anesthetized, euthanized, and their bloods collected by cardiac puncture for dosage of cholecystokinin (CCK) and other biochemical parameters. Supplementation with AHTI significantly decreased fasting glucose, body weight gain, and food intake. These effects may be attributed to increased satiety, once supplemented animals showed no evidence of impaired nutritional status and also because AHTI increased CCK production. Thus, our results indicate that AHTI, besides reducing fasting glucose, can reduce weight gain via food intake reduction.

A Trypsin Inhibitor from Tamarind Reduces Food Intake and Improves Inflammatory Status in Rats with Metabolic Syndrome Regardless of Weight Loss

Trypsin inhibitors are studied in a variety of models for their anti-obesity and anti-inflammatory bioactive properties. Our group has previously demonstrated the satietogenic effect of tamarind seed trypsin inhibitors (TTI) in eutrophic mouse models and anti-inflammatory effects of other trypsin inhibitors. In this study, we evaluated TTI effect upon satiety, biochemical and inflammatory parameters in an experimental model of metabolic syndrome (MetS). Three groups of n = 5 male Wistar rats with obesity-based MetS received for 10 days one of the following: (1) Cafeteria diet; (2) Cafeteria diet + TTI (25 mg/kg); and (3) Standard diet. TTI reduced food intake in animals with MetS. Nevertheless, weight gain was not different between studied groups. Dyslipidemia parameters were not different with the use of TTI, only the group receiving standard diet showed lower very low density lipoprotein (VLDL) and triglycerides (TG) (Kruskal–Wallis, p < 0.05). Interleukin-6 (IL-6) production did not differ between groups. Interestingly, tumor necrosis factor-alpha (TNF-α) was lower in animals receiving TTI. Our results corroborate the satietogenic effect of TTI in a MetS model. Furthermore, we showed that TTI added to a cafeteria diet may decrease inflammation regardless of weight loss. This puts TTI as a candidate for studies to test its effectiveness as an adjuvant in MetS treatment.

DETERMINAÇÃO DA ATIVIDADE ANTITRÍPTICA EM PROTEÍNAS DE PRODUTOS DO AMENDOIM ISOLADAS POR CROMATOGRAFIA DE AFINIDADE

The peanut is an oleaginous plant of high nutritional value, a source of protein and a trypsin inhibitor. Trypsin inhibitors are proteins present in the vegetable kingdom, considered anti-nutritional factors for animals. However, there have been several recent reports about their heterologous and beneficial effects on human health. These important effects have been the focus of studies investigating these inhibitors in foods. The aim of the present study was to isolate and determine the estimated molecular mass and specific inhibitory activity, for trypsin in the Japanese peanut, peanut butter, and peanut nougat using the techniques of precipitation with ammonium sulfate and affinity chromatography on trypsin - Sepharose CNBr 4B. The techniques used in this study were efficient for isolating the protein inhibitors with antitryptic specific activity of 694 UI mg-1, 823 UI mg-1 and 108 UI mg-1 for the Japanese peanut, peanut nougat, and peanut butter, respectively. The techniques featured high selectivity of the adsorbent, with consequent efficiency in isolation, given the low amount of dosed proteins and specific antitryptic activity presented by the products studied. The various health-related benefits show the importance of detecting and isolating efficient trypsin inhibitors in foods, taking into account the health claims attributed to the vegetable and its high consumption by humans.

Acute Effects of High-Intensity Interval and Moderate-Intensity Continuous Exercise on GLP-1, Appetite and Energy Intake in Obese Men: A Crossover Trial

This study investigated the effect of high-intensity interval (HIIE) and moderate-intensity continuous exercise (MICE) on glucagon-like peptide 1 (GLP-1), appetite and energy intake (EI) in obese men. In a randomized crossover trial, 12 participants (28.4 ± 2.6 years, 35.5 ± 4.5 kg/m2, 39.8 ± 2.2% body fat) performed: (I) Control (CON, no exercise); (II) MICE (20 min, 70% of maximal heart rate) and (III) HIIE (10 × 1 min at 90% of maximal heart rate with 1 min recovery). GLP-1 and appetite were assessed at: (I) PRE: pre-exercise; (II) POST: immediately post-exercise; (III) POST-1 h: 1 h post-exercise. EI was assessed after an ad libitum meal offered 1 h post-exercise and over 24 h. There was a significant time × condition interaction for GLP-1 (p = 0.035). Higher GLP-1 levels in MICE vs. CON (p = 0.024) and a trend for HIIE vs. CON (p = 0.069) POST-1h was found. Hunger was reduced immediately post-HIIE compared to CON (p < 0.01), but was not sustained POST-1 h (p > 0.05). EI did not differ between the sessions 1 h post-exercise or over 24H (p > 0.05). In summary, although MICE increased GLP-1 levels POST-1h and HIIE induced a transient reduction in hunger, both exercise protocols did not impact EI in obese men.

Gastroprotective and antielastase effects of protein inhibitors from Erythrina velutina seeds in an experimental ulcer model

Trypsin and chymotrypsin inhibitors from Erythrina velutina seeds have been previously isolated by our group. In previous studies using a sepsis model, we demonstrated the antitumor and anti-inflammatory action of these compounds. This study aimed to evaluate the gastroprotective and antielastase effects of protein inhibitors from E. velutina seeds in an experimental stress-induced ulcer model. Two protein isolates from E. velutina seeds, with antitrypsin (PIAT) and antichymotrypsin (PIAQ) activities, were tested. Both protein isolates showed a high affinity and inhibitory effect against human neutrophil elastase, with 84% and 85% inhibition, respectively. Gastric ulcer was induced using ethanol (99%) in 6 groups of animals (female Wistar rats, n = 6). Before ulcer induction, these animals were treated for 5 days with one of the following: (1) PIAT (0.2 mg·kg-1), (2) PIAT (0.4 mg·kg-1), (3) PIAQ (0.035 mg·kg-1), (4) ranitidine hydrochloride (50 mg·kg-1), (5) saline solution (0.9%), or (6) no intervention (sham). Both PIAT and PIAQ protected gastric mucosa, preventing hemorrhagic lesions, edema, and mucus loss. No histologic toxic effects of PIAT or PIAQ were seen in liver and pancreatic cells. Our results show that protein isolates from E. velutina seeds have potential gastroprotective effects, placing these compounds as natural candidates for gastric ulcer prevention.

Atividade antitríptica de proteínas em polpas e sementes de frutas tropicais

A healthy and diversified eating is essential for the maintenance of physical and mental health, and despite the current trend that appreciates the convenience of eating, it is noted that the population is increasingly consuming fruit, both in natura and / or juices. However, the use of certain fresh fruits is accompanied by the consumption of the seeds, peels or other parts may contain antinutritional factors, molecules and / or compounds that may adversely affect the bioavailability and / or digestibility of nutrients, such as inhibitors of trypsin. Such inhibitors may impair the utilization of proteins in food, but recent studies have been published also demonstrating the beneficial effects of the same. This study aimed to evaluate the trypsin inhibitors in aqueous extracts of fruits: guava (Psidium guajava L) varieties Kumagai (white) and Paluma (red), yellow passion fruit (Passiflora edulis f.) and watermelon (Citrullus vulgaris Schrad). Tests were done in order to detect the presence of antitryptic activity and the dosage of soluble proteins. Trypsin inhibitory activity was detected in all extracts tested, as well as soluble proteins. Thus, inhibition can be explained by the presence of an inhibitor protein, because it was possible, in seed extracts, in SDS-PAGE, to visualize a wide range of protein bands. It is noteworthy that in the study, the protein bands that coincide with the molecular masses of the trypsin inhibitors did not appear in a majority, showing that seed extracts are likely to have protein inhibitor, however sparingly, justifying the low antitryptic activity (1, 36 to 15.15 IU / mg of dry weight), also shown by the extracts of the pulp. Therefore, having the recommended consumption of fruits including guava, passion fruit and watermelon in sight, possibly this inhibitory activity is more related to benefits than to hazards, regarding ones health. However, it is important to emphasize a careful consumption of large quantities of seeds present in these fruits.

ASSESSMENT OF THE HEMOAGLUTINANT AND DIGESTIVE ENZYME INHIBITORY ACTIVITY OF EXTRACTS OBTAINED FROM DIFFERENT PARTS OF ATEMOIA

1PhD candidate, Graduate Program in Health Sciences, Federal University of Rio Grande do Norte, Natal-RN, Brazil. E-mail: alexandreserquiz@ gmail.com 2Master’s Degree candidate, Graduate Program in Biochemistry, Federal University of Rio Grande do Norte, Natal-RN, Brazil. E-mail: raphaserquiz@hotmail.com 3BSc Nutrition and Food Sciences, Federal University of Rio Grande do Norte, Natal-RN, Brazil. E-mail: thayanekerbele@gmail.com 4PhD,Department of Biochemistry, Federal University of Rio Grande do Norte, Natal-RN, Brazil. E-mail: elizeu@ufrnet.br 5PhD, Department of Biochemistry, Federal University of Rio Grande do Norte, Natal-RN, Brazil. E-mail: hugo@cb.ufrn.br Corresponding author: E-mail: alexandreserquiz@gmail.com