Antioxidant, anti-inflammatory and anti-obesity effects of onion and its by-products in high-fat fed rodents: a systematic review

The effects of onion and its by-products on metabolic changes induced by excessive consumption of a high fat diet have been the focus of many studies. The aim of this study was to systematically review the effects of onion and its by-products antioxidant, anti-inflammatory and anti-obesity in rats exposed to a high-fat diet. Five databases were used: Pubmed, EMBASE, Science Direct, Web of science and Scopus until June 2020 updated December 1, 2022. Research of the articles was carried out by two reviewers, searching and selecting studies after an initial reading of the titles and abstracts. In total, 2,448 papers were found and, after assessing against the inclusion and exclusion criteria, 18 papers were selected for this review. The findings of this review show the beneficial effects of onion and its by-products on inflammatory parameters, obesity, cardiovascular disease, thermogenesis and hepatic alterations generally associated with the consumption of a high-fat diet.

Perinatal exposure to a high-fat diet alters proopiomelanocortin, neuropeptide Y and dopaminergic receptors gene expression and the food preference in offspring adult rats

Exposure to the hight-fat diet may alter the control of food intake promoting hyperphagia and obesity. The objective of this study was to investigate the effects of this diet on dopamine receptors (drd1 and drd2), proopiomelanocortin (pomc), neuropeptideY (npy) genes expression, and preference food in adult rats. Wistar female rats were fed a hight-fat or control diet during pregnancy and lactation. The offspring were allocated into groups: Lactation - Control (C) and High-fat (H). Post-weaning - Control Control (CC), offspring of mothers C, fed a control diet after weaning; Control Hight-fat (CH), offspring of mothers C, fed a hight-fat diet after weaning; Hight-fat Control (HC), offspring of mothers H, fed with control diet after weaning; and Hight-fat Hight-fat (HH), offspring of mothers H, fed a H diet after weaning. The groups CH and HH presented greater expression of drd1 in comparison to the CC. The drd2 of CH and HC presented higher gene expression than did CC. HH presented higher pomc expression in comparison to the other groups. HC also presented greater expression in comparison to CH. The npy of HH presented greater expression in relation to CH and HC. HH and HC have had a higher preference for a high-fat diet at 102º life's day. The high-fat diet altered the gene expression of the drd1, drd2, pomc and npy, and influencing the food preference for high-fat diet.

Influence of mother nutrition during pregnancy and/or lactation on offspring food preference in experimental models

Abstract Introduction Understanding associations between food preferences and maternal nutrition during pregnancy and lactation could inform efforts to understanding the obesity mechanisms and provide insight to prevent it. Objective: To identify studies that investigated the effects of nutritional interventions during the pregnancy and lactation on the food preferences of offspring. Method: The review was conducted with search for articles in the databases: Scopus, Pubmed, Medline, LILACS, Scielo and Science Direct. Exclusion criteria were used: reviews, human studies, studies with drugs or other substances not related to food. Results: At the end of the search in the databases, 176 references were found. After use the exclusion criteria, reading the titles, abstracts and full articles, were selected 11 articles to compose the review. Conclusion: The selected studies suggested that unbalanced nutrition in early life alters the food preference and neural components related to the consumption of fatty and sugary foods in offspring rodents.

Effects of maternal high fat intake during pregnancy and lactation on total cholesterol and adipose tissue in neonatal rats

AIM

Obesity during pregnancy is one of the most established risk factors for negative long-term programming. The aim of the present study was to investigate the effects of maternal consumption of a high-fat diet during pregnancy and lactation on the weight gain, visceral adipose tissue and cholesterolemia in neonatal rats.

METHODS

Wistar rats were divided into two groups according to the mother's diet during pregnancy and lactation: Control group (CG, n = 12) were the offspring of rats fed a standard diet (4% lipid) and the Test group (TG, n = 12) were pups rats fed on a high fat diet (23% lipid). The weight of the animals was measured on alternate days until the 22nd day of life, when collected visceral adipose tissue and blood were collected for biochemical analysis. For statistical analysis the Student t test, Sidak´s teste and two way ANOVA was used, with p <0.05.

RESULTS

the test group showed differences in weight gain, visceral adipose tissue and higher cholesterol.

CONCLUSION

a maternal exposure to a high-fat diet during pregnancy and lactation can promote changes in weight gain, hypercholesterolemia and an increase in adipose tissue in neonatal rats.

Sertraline delays the somatic growth and reflex ontogeny in neonate rats

This study investigated the somatic maturation and ontogeny of reflexes in neonate rats treated with sertraline (Sert) during the suckling period. The animals were divided into four groups; three that received daily doses of Sert (5, 10 or 15 mg/kg s.c.; groups Sert5, Sert10, and Sert15, respectively), and a fourth group that received distilled water (Dw) (1 ml/kg/b.w.). Growth indicators (body weight, axis of the head and tail length) were measured daily, from the 1st to the 21st postnatal day. The reflexes (righting, free-fall righting, negative geotaxis, cliff avoidance, auditory startle response, vibrissa placing and palm grasp) and physical-feature maturation (ear unfolding, auditory conduit opening, irruption of the lower incisors and eye opening) were recorded each day of the animal's life. All groups were compared to the Dw group. The body weight gain was reduced in all the Sert groups. Moreover, a delay in the growth of the body length was observed in all the Sert groups. Higher Sert doses reduced the speed of growth in the tail length. The medio-lateral head axis reduced in Sert15 and Sert5 doses. Otherwise, Sert10 had a temporary acceleration in this growth, but the growth of the anteroposterior head axis had a delay in all the Sert groups. The highest doses induced a delay in physical-feature maturation. The palm grasp reflex (disappearance) was retarded in Sert10; cliff avoidance advanced in Sert10; negative-geotaxis and free-fall righting retarded in Sert15. The findings suggest that altered serotonergic system activity induced by sertraline early in life could play a role in the retardation of the somatic growth ontogeny as well as a delay in the maturation of some reflexes.

The expression of an intraspecific aggressive reaction in the face of a stressor agent alters the immune response in rats

The repercussion on the immune response of the expression of intraspecific aggressiveness in the face of a stressor agent was investigated in rats. Ninety-day-old animals were divided into three groups: the control group (only immunological measurements were performed), the foot-shock (FS) (animals individually receiving FS), and the intraspecific aggressive response (IAR) group (animals receiving FS and presenting IAR). For immunological measurements, blood samples were collected promptly at 7 and 15 days after FS or IAR. The FS reduced the total leukocyte amount presented. However, aggressiveness triggered not only reduction of the leukocytes, but also lymphocyte decrease and neutrophil increase. Moreover, an elevation in total leukocytes associated with an increase in the humoral immune response was also observed one week after IAR. In this study, the expression of intraspecific aggressiveness in the face of a stressor seemed to activate the immune system and to potentiate the antigen specific humoral response.

Malnutrition during brain growth spurt alters the effect of fluoxetine on aggressive behavior in adult rats

Malnutrition effect during the suckling period on aggressive behavior was investigated in adult rats treated and not treated with fluoxetine, a selective serotonin reuptake inhibitor. Sixty-four Wistar male rats were allocated in two groups, according to their mothers' diet during lactation. The well-nourished group was fed by mothers receiving a 23% protein diet; the malnourished one by mothers receiving a 8% protein diet. Following weaning, all rats received the 23% protein diet. On the 90th day after birth, each nutritional group was divided into two subgroups, one receiving a single daily injection of fluoxetine (10 mg/kg) and the other of a saline solution (0.9% NaCl) for 14 days. Treatment with Fluoxetine reduced aggressive response in well-nourished but not in malnourished rats. These findings suggest that the serotoninergic system was affected by malnutrition during the critical period of brain development, and persisted even after a long period of nutritional recovery.