Ameliorative Effects of Mulberry (Morus albaL.) Leaves on Hyperlipidemia in Rats Fed a High-Fat Diet: Induction of Fatty Acid Oxidation, Inhibition of Lipogenesis, and Suppression of Oxidative Stress

Abstract

To determine the effects of mulberry (Morus alba L.) leaves on hyperlipidemia, we performed gene expression profiling of the liver. Rats were fed a high-fat diet and administered mulberry leaves for 7 weeks. Plasma triglyceride and non-esterified fatty acid levels were significantly lower in the rats treated with mulberry leaves as compared with the untreated rats. DNA microarray analysis revealed that mulberry leaves upregulated expression of the genes involved in α-, β- and ω-oxidation of fatty acids, mainly related to the peroxisome proliferator-activated receptor signaling pathway, and downregulated the genes involved in lipogenesis. Furthermore, treatment with mulberry leaves upregulated expression of the genes involved in the response to oxidative stress. These results indicate that consumption of fatty acids and inhibition of lipogenesis are responsible for the reduction in plasma lipids caused by mulberry administration. In addition, mulberry treatment maintains the body's oxidative state at a low level despite enhancing fatty acid oxidation.

Mulberry leaves (Morus alba L.) ameliorate obesity-induced hepatic lipogenesis, fibrosis, and oxidative stress in high-fat diet-fed mice

“…The activation of PPARa regulates lipoprotein metabolism, which enhances hepatic uptake and increases the esterification of free fatty acids (Fruchart and Duriez 2006) as well as activation of mitochondrial fatty acid oxidation. Kobayashi et al (2010) confirmed that mulberry had regulatory effects on the PPAR-mediated pathway, PPARa, and/or PPARd, which is involved in energy expenditure. Interestingly, a previous report suggested that supplementation with short-chain fatty acids (SCFA) reduced HFD-induced hepatic steatosis, but PPARc deficiency blocked the ameliorating effect of SCFA supplementation on hepatic steatosis by regulation of UCP2 and AMP-activated protein kinase (den Besten et al 2015).…”

“…In our previous study, mulberry leaf has shown anti-inflammation and antioxidant effects on obesity (Lim et al 2013b). Earlier studies suggest some potential effects of the mulberry leaf on regulation of the antioxidant defense system and dyslipidemia in vivo and in vitro (Kobayashi et al 2010;Liu et al 2008;Peng et al 2011). In addition, mulberry leaf has several effects such as scavenging free radicals, inhibiting oxidation, and reducing atherogenic risk (Liu et al 2008).…”

“…In addition, PPARa stimulates fatty acid uptake and oxidation in mitochondria. A previous study proved that decreases in mitochondrial fatty acid oxidation and energy expenditure stimulated excessive accumulation of TG in the liver (Kobayashi et al 2010). The activation of PPARa regulates lipoprotein metabolism, which enhances hepatic uptake and increases the esterification of free fatty acids (Fruchart and Duriez 2006) as well as activation of mitochondrial fatty acid oxidation.…”

“…Interestingly, a previous report suggested that supplementation with short-chain fatty acids (SCFA) reduced HFD-induced hepatic steatosis, but PPARc deficiency blocked the ameliorating effect of SCFA supplementation on hepatic steatosis by regulation of UCP2 and AMP-activated protein kinase (den Besten et al 2015). However, PPARa would be a main regulator among the PPAR families in MLE treatment according to DNA microarray experiment in HFD-fed mice (Kobayashi et al 2010). The current study demonstrated that MLE induced up-regulation of gene expression and/or protein level of PPARa and UCP2 in liver.…”

Modification of abomasum contractility by flavonoids present in ruminants diet: in vitro study

“…The idea of employing flavonoids as plant-derived feed additives results from the wide spectrum of their physiological and pharmacological effects (Harborne and Williams, 2000;Khayyal et al, 2001;Githiori et al, 2006). Especially the antioxidant property of flavonoids and their ability to affect the activity of several metabolic enzymes are very promising in dairy cows, since they can experience oxidative stress during the peripartum period (Bernabucci et al, 2005;Kobayashi et al, 2010). Furthermore, flavonoid supplementation was shown to improve rumen fermentation parameters, limit the incidence of rumen acidosis (Balcells et al, 2012) and slightly increase the milk yield in dairy cows (Nielsen and Hansen, 2004;Gohlke et al, 2011).…”