Perinephric and epididymal fat affect hepatic metabolism in rats.
Obesity (Silver Spring)
; 20(1): 151-6, 2012 Jan.
Article
en En
| MEDLINE
| ID: mdl-21818154
ABSTRACT
The present study examined whether the perinephric and epididymal visceral fat (PEVF) depot under short-term excess nutrient protected the liver by trapping nutrient-derived nonesterified free fatty acids (NEFAs) or had deleterious effects on hepatic triglycerides (TGs) accumulation and insulin resistance due to adipokine secretion. Young rats pre-emptively underwent surgical PEVF removal or sham operations and were fed with either high-fat diet (HFD) (PEVF-HFD) or regular chow (RC) (PEVF-RC) for 3 days. Insulin sensitivity was measured by hyperinsulinemic-euglycemic clamp. Liver TG, serum NEFA, and fat-derived adipokines were assessed. Insulin and lipogenesis signaling were assessed by western blots. Pre-emptive PEVF removal significantly decreases insulin-induced suppression of hepatic glucose production (HGP) both in RC and in HFD-fed rats. In accordance with the clamp results, hepatic TG accumulation is also significantly reduced by PEVF excision both in RC and HFD-fed rats. These results are further validated by insulin signaling results, which show that pre-emptive PEVF removal increases phosphorylation of hepatic Akt, irrespective of diet. Notably, high levels of serum leptin induced by HFD are significantly reduced by pre-emptive PEVF excision. Additionally, expression of lipogenic enzyme p-acetyl-CoA-carboxylase, denoting reduced lipogenesis, is increased in the PEVF-HFD rats. In conclusion, PEVF has a deleterious effect on the liver as a source of insulin resistance-inducing adipokines irrespective of diet, and does not serve as a buffer for excess nutrients.
Texto completo:
1
Base de datos:
MEDLINE
Asunto principal:
Triglicéridos
/
Grasa Intraabdominal
/
Hígado Graso
/
Dieta Alta en Grasa
/
Hígado
/
Obesidad
Tipo de estudio:
Etiology_studies
Límite:
Animals
Idioma:
En
Revista:
Obesity (Silver Spring)
Asunto de la revista:
CIENCIAS DA NUTRICAO
/
FISIOLOGIA
/
METABOLISMO
Año:
2012
Tipo del documento:
Article
País de afiliación:
Israel