Resveratrol and Decreased Fat Deposition in C. elegans

Alexandra ******- Period 3

Manhasset Science Research

1998

Obesity Trends* Among U.S. Adults1990, 1998, 2007

(*BMI 30, or about 30 lbs. overweight for 5’4” person)

2007

1990

No Data <10% 10%–14% 15%–19% 20%–24% 25%–29% ≥30%

Source: Center for Disease Control & Prevention [http://www.cdc.gov/nccdphp/dnpa/obesity/trend/maps/obesity_trends_2007.ppt#487,5,Slide 5]

Need

Knowledge Base

Figure 1: Chemical structure of Nile Red (A) & Sudan Black (B) staining. Nile Red staining in wild-type and mutant C. elegans (C-E). Sudan Black staining in wild-type (F) & mutant (G) organisms.Source: (Ashrafi, 2007) [http://www.wormbook.org/chapters/www_obesity/obesity.html]

Resveratrol

Figure 2: chemical structure of resveratrol (C14H12O3)

[http://www.3dchem.com/molecules.asp?ID=277]

• Chemical found in grapes; red wine

• Popular dietary supplement- advertised as anti-aging substance

•May explain “French paradox”

Literature ReviewRNAi in E. coli food

ingested by C. elegans

Mutant C. elegans strains

Nile Red Staining ingested

Wild-type C. elegans

Fat deposition monitored as RNAi silences genes

Results

305 gene silences cause reduced fat storage

112 gene silences cause increased fat storage

Figure 2: RNAi was used to silence certain genes to determine which ones regulated fat in C. elegans (Ashrafi, et al, 2003) [chart made by author using materials from article]

Literature Review

• C. elegans in dauer need AMP-activated protein kinase (AMPK) to survive– Dauer- larval “hibernation”

stage in which metabolic rate is slowed; fat deposits increase to sustain organism

– AMPK- fat regulatory enzyme

• aak2 mutant dauers lack AMPK destroy fat

• (Roy, et al, 2009)

C. Elegans dauerorganisms

Wild-type N2 strain-Has AMPK

aak-2 mutant strainNo AMPK

Sudan Blackstaining

Sudan Blackstaining

Fat reservesRationed at

Constant level

Fat reservesdestroyed

Organisms died

Figure 3: The enzyme AMPK is necessary for C. elegans in dauer to survive and regulate fat deposition (Roy, et al, 2009) [chart created by author]

Literature Review• Resveratrol

improves health and survival of mice on a high-calorie diet

• (Baur, et al, 2006)

Positive effects ofResveratrol

in mice

Increased survival

Activation of AMPK Increased insulin

Sensitivityless fatty acid

syntase

More mitochondriaLess damage to

Liver and pancreas

Figure 4: Resveratrol caused many positive changes in the overall health of mice similar to the effects of caloric restriction

(Baur, et al, 2006) [chart made by author adapted from article]

Literature Review

Human preadipocytes

prevented from becomingfat cells

Decreasedfat storage

Stimulates adiponectin

Anti-obesity properties

of resveratrol

Figure 5: In human preadipocytes (fat cell precursors), resveratrol in extremely high doses (3-5 g) caused positive changes in the cells. (Fischer-Posovsky, et al, 2008) [chart made by author]

Purpose/Hypothesis

• Purpose: to observe the effects of resveratrol on fat deposition in C. elegans and comparing it to caloric restriction

• Null hypothesis: Resveratrol will cause no change in fat deposition in C. elegans

• Alternate hypothesis: Resveratrol will cause a decrease in fat deposition and mimic the effects of caloric restriction

Methodology

C. ElegansN= 75

25= control- no resveratrol

or caloric restriction

25= experimental- caloric restriction

25= experimental- Resveratrol

(5.0 mg/kg per day)

Sudan Black StainingInserted into E. coli food-

Ingested by organism

Fluorescent microscopeexamination

Statistical analysis-Using SPSS program

Budget

Vendor Order # Quantity Description Unit Price Total Price

Caenorhabditis Genetic Center TJ3014 10 Wild-type C. elegans N2 $7.00 $70.00

GNC 429702 1 Resveratrol- 500 mg $74.99 $74.99

Carolina Biological 2009 NP-17-3500 2 Sudan III Stain $26.85 $53.70

Total Price: $198.69

Do-ability

• Resveratrol studies have been done in previous years

• C. elegans is a useful model organism that is easily obtained

• Sudan Black staining and fluorescent microscope examination are possible