Immune Netw.  2011 Apr;11(2):107-113. 10.4110/in.2011.11.2.107.

Dietary Aloe Reduces Adipogenesis via the Activation of AMPK and Suppresses Obesity-related Inflammation in Obese Mice

• Shin E
• Shin S
• Kong H
• Lee S
• Do SG
• Jo TH
• Park YI
• Lee CK
• Hwang IK
• Kim K

• KMID: 2150698
• DOI: http://doi.org/10.4110/in.2011.11.2.107

Abstract

BACKGROUND
Metabolic disorders, including type II diabetes and obesity, present major health risks in industrialized countries. AMP-activated protein kinase (AMPK) has become the focus of a great deal of attention as a novel therapeutic target for the treatment of metabolic syndromes. In this study, we evaluated whether dietary aloe could reduce obesity-induced inflammation and adipogenesis.
METHODS
Male C57BL/6 obese mice fed a high-fat diet for 54 days received a supplement of aloe formula (PAG, ALS, Aloe QDM, and Aloe QDM complex) or pioglitazone (PGZ) and were compared with unsupplemented controls (high-fat diet; HFD) or mice fed a regular diet (RD). RT-PCR and western blot analysis were used to quantify the expression of obesity-induced inflammation.
RESULTS
Aloe QDM complex down-regulated fat size through suppressed expression of scavenger receptors on adipose tissue macrophages (ATMs) compared with HFD. Both white adipose tissue (WATs) and muscle exhibited increased AMPK activation through aloe supplementation, and in particular, the Aloe QDM complex. Obesity-induced inflammatory cytokines (IL-1beta and -6) and HIF1alpha mRNA and protein were decreased markedly, as was macrophage infiltration by the Aloe QDM complex. Further, the Aloe QDM complex decreased the translocation of NF-kappaB p65 from the cytosol in the WAT.
CONCLUSION
Dietary aloe formula reduced obesity-induced inflammatory responses by activation of AMPK in muscle and suppression of proinflammatory cytokines in the WAT. Additionally, the expression of scavenger receptors in the ATM and activation of AMPK in WAT led to reduction in the percent of body fat. Thus, we suggest that the effect of the Aloe QDM complex in the WAT and muscle are related to activation of AMPK and its use as a nutritional intervention against T2D and obesity-related inflammation.

Keyword

Aloe QDM complex; Type 2 diabetes mellitus; AMPK; Obesity-induced inflammation

MeSH Terms

Adipogenesis
Adipose Tissue
Adipose Tissue, White
Aloe
AMP-Activated Protein Kinases
Animals
Blotting, Western
Cytokines
Cytosol
Developed Countries
Diabetes Mellitus, Type 2
Diet
Diet, High-Fat
Humans
Inflammation
Macrophages
Male
Mice
Mice, Obese
Muscles
NF-kappa B
Obesity
Receptors, Scavenger
RNA, Messenger
Thiazolidinediones
AMP-Activated Protein Kinases
Cytokines
NF-kappa B
RNA, Messenger
Receptors, Scavenger
Thiazolidinediones

Figure

• 

  Figure 1 Effects of aloe formulas on cell counts in the epididymal fat pad. The fat cell count in 7.35 mm2 from hematoxylin and eosin-stained paraffin sections of the fat pad.

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  Figure 2 Effects of aloe formulas on obesity-related inflammatory receptors. WAT were isolated from mice. mRNA expression of scavenger receptors in the WAT were measured by RT-PCR. This was repeated in triplicate and similar results were obtained in all three.

• 

  Figure 3 Effects of aloe formulas on AMPK phosphorylation. WAT and muscles were isolated from mice. Protein expression in the (A) WAT and (B) muscles were measured by western blot. This was repeated in triplicate and similar results were obtained in all three.

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  Figure 4 Effects of aloe formulas on proinflammatory cytokines. WAT were isolated from mice. (A) Protein expression of HIF1α were measured by western blot. (B) mRNA expression of IL-1β and IL-6 were measured by RT-PCR. This was repeated in triplicate and similar results were obtained in all three.

• 

  Figure 5 Effects of aloe formulas on NF-κB activation. WAT were isolated from mice. Protein expression of NF-κB p65 were measured by western blot. This was repeated in triplicate and similar results were obtained in all three.

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