I presented a slightly modified version of this paper published on 23 June, 2015 in the journal 'Nature Communications' in the final of my seminar presentation course of Masters (GEB-507).
2. Introduction
• A medicinal mushroom
• Used in traditional Chinese medicine
to promote health and longevity
• Putative anti-diabetic effects
• Previous studies
- triterpenes and polysaccharides
isolated from this fungus inhibit
adipocyte differentiation and
lower serum glucose on type 2 diabetes mellitus mice
- proteoglycans isolated from its fruiting bodies induce
antidiabetic, antihyperlipidemic and antioxidant activities.
• The effects on gut microbiota, inflammation and obesity-related
disorders remained unknown.
Ganoderma lucidum
3. • A disease condition associated with numerous health problems
and a reduced life expectancy.
• Closely linked with intestinal dysbiosis and chronic inflammation,
which can lead to –
- insulin resistance
- type 2 diabetes
- fatty liver disease
- cardiovascular disease
- obstructive sleep apnea and
- cancer
• The high prevalence is currently a major threat to public health,
with ~ 500 million obese people and
1.4 billion overweight individuals worldwide.
Obesity
4. • To determine the effects of a water extract of G.
lucidum (WEGL) on obesity, inflammation and
insulin resistance in HFD-fed mice.
Objective
5. Methods
Murine strain
(C57BL/6NCrl Bltw)
Processing of the water extract
G. lucidum (WEGL)
Determination of energy
and fat in feces
qRT-PCR
Biochemical analysis
Fecal transplantation
Oil red O staining
Oral glucose tolerance test
Cytokine measurements
Morphometry analysis
of epididymal adipose tissues
Determination of bacteria by
quantitative real-time PCR
Gut microbiota analysis
Statistical analysis
Western blotting
7. Results: Obesity and fat accumulation were
reversed by fecal transplantation from
WEGL-treated mice to HFD-fed mice
Fig 5 a-d
8. Results: WEGL reduced pro-inflammatory
cytokine expression in liver and adipose
tissues of HFD-fed mice
Fig 2 a-d , 6a
Following fecal transplantation
9. Results: WEGL reduced serum LPS and TLR4-
related signaling pathways in HFD mice
Fig 3 a-c
10. Results: WEGL may improve intestinal integrity
in HFD-fed mice
Following fecal
transplantation
Fig: 6 e-f, Sup. 8
11. Results: WEGL altered HFD-induced gut dysbiosis and
WEGL fecal transplants modulated gut
microbiota composition
Fig 4c, 7 c,
sup. 9
12. Fig 8 a-e
WEGL high molecular weight polysaccharides reduce
body weight and fat accumulation in HFD-fed mice
13. • As SCFAs are produced from fermentation of polysaccharides and
some other prebiotics by gut bacteria (i.e., Bacteroides spp.) and
the percentage of Bacteroides was enhanced by 8% WEGL
treatment in HFD mice, it is possible that the amount of SCFAs may
also increase.
• It remains to be determined
- whether SCFAs are affected or not by WEGL and
- whether these molecules contribute to the anti-inflammatory
effect of WEGL.
Scope for Future Research
14. Summary
• WEGL reduces dietary-induced obesity, body weight, fat
accumulation as well as chronic inflammation in the liver and
adipose tissues of HFD-fed mice.
• WEGL alters microbiota composition in HFD-fed mice.
• WEGL may improve intestinal integrity in HFD-fed mice
• WEGL reduces serum LPS (therefore, endotoxemia) and TLR4-related
signaling pathways in HFD mice.
• WEGL fecal transplants reduce pro-inflammatory cytokines, obesity
and fat accumulation; modulate gut microbiota composition and
increase intestinal tight junction expression in HFD-mice.
• Both WEGL and its high Mw polysaccharides (>300 kDa) may be used
as prebiotics to reduce gut dysbiosis, chronic inflammation and
obesity-related metabolic disorders in obese individuals.