Ageless Animals and Plants Richa Banthia BIOL 4097 September 9 th , 2014
Jul 12, 2015
Ageless Animals and Plants
Richa BanthiaBIOL 4097
September 9th, 2014
Introduction & Outline
• Ageless Plants and Animals – Where is this research heading? Is aging not a requirement?
• What is Aging?
– Mechanisms of Aging
– Theories of Aging
• What is Negligible Senescence?
• Review of Plants & Animals displaying NS
• Conclusion and modern day Research
Survivorship vs. Age
http://poseidonsciences.scienceblog.com/files/2010/08/Aging-Scienceblog-Survivorship-curve-2006-Census.jpg
Average Life Span in the US
• Current Life Expectancy
78.74 years
http://i.dailymail.co.uk/i/pix/2013/01/09/article-2259763-16D65AD6000005DC-767_306x423.jpg
Supercentenarians
• Jeanne Calment (1875-1997)
• Longest living person at 122 years old
• Met Vincent van Goh, ate 2 lbs. of chocolate EVERY week, rubbed her skin with olive oil
http://www.nytimes.com/1997/08/05/world/jeanne-calment-world-s-elder-dies-at-122.html
Supercentenarians: 127 year old Leandra Lumbreras
http://metrouk2.files.wordpress.com/2014/08/166.png
Supercentenarians
• Mexican woman Leandra Becerra Lumbreras turned 127 years old on Sunday, August 31st.
• Born: August 31st, 1887 (no birth certificate)
• 73 great-grand children
• 55 great-great grand children
• Secrets to long life: sing, eat chocolate, sleep and don’t get married
http://www.dailymail.co.uk/news/article-2739036/Mexican-woman-Leandra-Becerra-Lumbreras-oldest-person-lived-127.html
What is aging?
• Defined as “the condition or process of deterioration with age” and “the loss of a cell’s power of division and growth.”
• Involves deterioration of cardiovascular, digestive, nervous, reproductive and urinary systems.
• More prone to development of age related diseases
http://www.hindawi.com/journals/tswj/2002/704240/abs/
Challenges of Aging
Age Related Diseases
• Arthritis
• Cancer
• Alzheimer’s
• Diabetes
• Heart Disease
• Depression
Age Related Conditions
• Loss of hearing, vision, etc.
• Loss of coordination
• Increased proportion of fat to muscle
• Loss of bone density
Three Classical Theories of Aging
1. Mutation Accumulation Theory Sir Peter Medawar 1952
• Suggests that random mutations accumulate later in life such that they cannot be selected against
• Why? By this time, you will have already passed your genes to offspring.
• Over time, these mutations accumulate leading to increased mortality in later life.
http://www.hindawi.com/journals/tswj/2002/704240/abs/
Three Classical Theories of Aging
2. Antagonistic Pleiotropy TheoryGeorge C. Williams 1957
• Pleiotropy: one gene influences multiple phenotypic traits
• Tradeoff between fertility and longevity
• Genes that are beneficial early in life in order to reproduce, become harmful later in life
• Suggests that if the benefits outweigh the negatives, the gene will always be selected for.
http://www.hindawi.com/journals/tswj/2002/704240/abs/
2. Antagonistic Pleiotropy TheoryGeorge C. Williams 1957
Example: Testosterone production in males
In early life, production of testosterone controls sex drive, sperm production, muscle mass, etc. Later in
life, this same action can cause prostate issues.
http://awarnach.mathstat.dal.ca/~joeb/biol3046/projects/AGE2/Antagonistic%20Pleiotropy%20Theory.htm
Three Classical Theories of Aging
3. Programmed Death Theory August Weismann 1882
• Aging of cells is genetically programmed
• Supported by the idea that within species, life span is fairly constant
• Suggested that life span of species is dependent on the number of somatic cell regenerations
• Other evidence: “senescent cells are resistant to apoptosis” by inhibiting caspase 3 (part of programmed cell death pathway) which causes dysfunction of various tissues
http://www.discoverymedicine.com/Jie-Shen/2009/11/24/programmed-cell-death-and-apoptosis-in-aging-and-life-span-regulation/
Programmed Cell Death Pathway
http://www.bumc.bu.edu/phys-biophys/files/2010/04/intrinsic-apoptotic-pathway.jpg
Hayflick’s Limit: Molecular Clock Leonard Hayflick 1961
• A cell can multiply a limited number of times
• 3 phases of cell growth:
– Phase 1: Rapid cell division
– Phase 2: Cell division slows
– Phase 3: Cells stop dividing : “senescence” and cell death occurs.
• Human cell’s stop dividing after 50 divisions
http://longevity-science.org/Evolution.htm
Hayflick’s Limit
http://www.nature.com/nrm/journal/v1/n1/fig_tab/nrm1000_072a_F3.html
Mechanisms of Aging
http://cubocube.com/files/images/e/2/e2ebd42c8333191ad90b0db81f44957566f1961b.jpg
Closer Look: Telomere Shortening
• Telomere length and telomere capping both contribute to cellular senescence
• DNA Polymerase cannot fully synthesize 3’ end of lagging strand: End Replication Problem
• Telomerase synthesizes short repeating sequence TTAGGG added to 3’ end of DNA lagging strand
• Telomere shortening could act as a cellular time keeper
http://www.senescence.info/telomeres_telomerase.html
Telomerase length vs. Age
http://www.nature.com/nrg/journal/v13/n10/images/nrg3246-f2.jpg
Closer Look: Telomere Capping
• Structure via electron microscopy
• Telomeres form T-loops that contains TRF-1 and TRF-2 (Telomere repeat binding factor)
• Loops prevent telomeres from being identified as damaged DNA.
• Also provide stability.
http://www.senescence.info/telomeres_telomerase.html http://web.pdx.edu/~newmanl/TelomereLoop.gif
TRF Length (Capping) vs. Age
http://www.anti-agingfirewalls.com/2014/02/03/nuclear-aging-the-view-from-the-telomere-end-of-the-chromsome-part-1-context-history-and-about-telomere-lengths-2/
Fin? Noggin’? DUUUUDE!
• https://www.youtube.com/watch?v=9YkxZvdCvYM
What is negligible senescence?
• What is it? And what does it mean? According to John C. Guerin…Director of the Centenarian Rockfish Project at Oregon State University
• “not only long lived, but they don’t grow old”
• “Chronological aging without increased mortality”
• “Continue to grow and reproduce after reaching maturity but show no evidence of senescence. In fact fecundity often increases with increasing age.”
http://www.lef.org/magazine/mag99/june99-report4.htm
Research and Measurement Techniques
• Determining the age of animals:
• Whales
– Harpoon points
– Otolith growth rings
– Otolith: structure in inner ear
• Fish
– Otolith growth rings
http://www.nmfs.noaa.gov/gallery/images/images/photos/20110404_5589334674.jpg
Research and Measurement Techniques
• Turtles
– Mark and recapture methods
• Lobster
– Estimation of body size
• Mollusks
– Growth rings in shell
ANIMALS DISPLAYING NEGLIGIBLE SENESCENCE
Yellow Rockfish
• Known to live up to 205 years old.
• 2013 Fishing controversy!
• Found from San Diego to the Bering Sea
• 16% sold are over the age of 50
Yellow Rockfish
• Hypothesis: Don’t age due to telomerase expression that doesn’t decrease with age
• Age measured by examining the otolith, a structure in the inner ear.
• Study by Dr. Guido Krupp shows that telomerase levels are independent of age.
http://www.agelessanimals.org/research2.htm
Aldabra, the giant tortoise
• Aldabra, the giant Tortoise
• Calculated life span of 255 years
• Died early in a zoo in India due to liver failure and infection – NOT AGE.
http://io9.com/5618046/the-mystery-of-why-turtles-never-grow-old---and-how-we-can-learn-from-it http://www.sciencephoto.com/image/378918/350wm/Z7520265-Aldabra_Giant_Tortoise-SPL.jpg
Aldabra, the giant tortoise• Hypothesis: Don’t age due to reactive oxygen
species/ oocyte regeneration/ high telomerase expression
• ROS: “chemically active free radicals” that are formed by metabolic energy production. Animals with slower metabolism have better control of ROS, thus less likely to have DNA damage.
http://90ways.com/sciarchive/sci61.php
Antarctic giant Sponge
• Antarctic sponge estimated to be 10, 000 years old• Average water temper of 4˚ Celsius slows biochemical
processes• “Slow motion” living• Lower rates of respiration, reproduction and
metabolism
http://www.montereyinstitute.org/noaa/lesson06/l6text.htm
Jellyfish
• Turritopsis dohrnii
• Benjamin Button jellyfish
• Found in Mediterranean sea and waters near Japan
• “Immortal” in the sense that it reverts back to embryonic form under stress…keeps rewinding life cycle.
http://www.ibtimes.com/immortal-jellyfish-ageless-aspen-trees-animals-plants-who-found-fountain-youth-998646
How does it work?
• Jellyfish forms cyst
• Develops into polyp colony
• Jellyfish cells are often totally transformed in this process.
https://www.fightaging.org/archives/2011/04/ageless-animals-the-jellyfish-edition.php
Bowhead Whales
- Discovered to be up to 210 years old- Age is estimated by investigating the types of
harpoon found in the whale blubber
http://img-fotki.yandex.ru/get/6713/207833497.1/0_ab022_6b3333a5_XL.jpg
Lobsters
• Age is difficult to measure due to molting
• Only way to estimate age is based on size observation
• Some over 3 feet long
• Longevity could be due to telomerase activity
http://www.smithsonianmag.com/science-nature/dont-listen-to-the-buzz-lobsters-arent-actually-immortal-88450872/?no-ist
Leach’s Storm Petrel
• Small seabird
• Average Life Span: 20 years
• Maximum recorded lifespan of 36 years.
• How? Telomere length increases with age.
http://www.bucknell.edu/x45446.xml
Leach’s Storm Petrel
Elongation hypothesis: Long lived birds tend to have increasing length of telomeresSelection hypothesis: Long lived birds start off with the longest telomeres http://mbe.oxfordjournals.org/content/25/
1/220.full.pdf+html
Naked mole rat
• Only mammal to show negligible senescence
• Live to 28 years old
• Most rodents of similar size only live 1-3 years
Quahog Clam
• Artica islandica
• Can live up to 400 years
• Found off the coast of Iceland
• Suggested that maintained antioxidant activity increases life span
http://news.nationalgeographic.com/news/2007/10/071029-oldest-clam.html
PLANTS DISPLAYING NEGLIGIBLE SENESCENCE
World’s Oldest Tree: Old Djikko in Dalarna Province, Sweden
• Spruce tree estimated to be 9,500 years old
• Dating back to last ice age using C-14 dating
• Current tree is a clone
Pando – The Trembling Giant
• Clonal colony of aspen trees made up of 50,000 clones
• Located in Utah
• 80, 000 year old root system
• Common root system spans 110 acres
http://www.leaflimb.com/blog/wp-content/uploads/2010/04/Pando1.jpg
The Senator
• Bald cypress in Seminole County, FL
• Tardium distichum
• Was the oldest known Cyprus tree at 3500 years old
• Burned down in 2012
https://www.gunandgame.com/attachments/gen-sherman-jpg.46821/
Methuselah
• Oldest non-clonal tree estimated to be 4,841 years old
• Bristlecone pine
• White Mountains, California
• Precise location is a secret to prevent damage
http://www.mnn.com/sites/default/files/styles/featured_blog/public/METHUSELAH.jpg
Chestnut Tree of One Hundred Horses
• Chestnut tree on Mount Etna in Sicily – 5 miles from an active volcano.
• Estimated to be between 2,000 – 4,000 years old • Circumference of 190 feet – “greatest tree girth” according
to Guinness World Records• Name comes from a legend where a queen and her 100
knights were able to take shelter under this tree during a storm.
https://yy2.staticflickr.com/3291/2817869138_30eb23d70d.jpg
Mediterranean Sea Grass
• Posidonia oceanica
• Grass like plants that is found at the bottom of the ocean
• Found near Ibiza, Spain
• Spans 5 miles
• Estimated to be 100,000 years old –world’s oldest organism
http://science.time.com/2014/02/25/worlds-oldest-things/photo/08_sussman_seagrass_0910_0753_1068px/
Olive Tree of Vouves
• Found in the island of Crete in the Greek isles
• Age: 3200 years
• Continues to produce high quantity of olives
• Resistant to stressors such as insects, droughts, fire, etc.
Strategies for Engineered Negligible Senescence (SENS)
• Dr. Aubrey de Grey• CEO of SENS• “master plan to cure aging” by
proposing engineering solutions to the 7 types of cell damage
• SENS is an extremely controversial topic
• Goal directed organization to prevent aging by bringing together scientists from various fields –gerontology and engineering.
• Results to completely defeat aging are still far off in the foreseeable future
http://mavericksofthemind.com/dr-aubrey-de-grey/6
SENS
http://www.sens.org/research/introduction-to-sens-research
Conclusion
• Aging is not a requirement and there are many organisms that display negligible senescence
• Many hypotheses involving telomere length –continued focus in research.
• Still a controversial topic to apply goals of negligible senescence to humans
• So for now….eat as much chocolate as possible!• Questions?
Referenceshttp://www.smart-publications.com/interviews/mavericks-of-medicine/john-guerin
http://genetics.thetech.org/original_news/news10
http://www.agelessanimals.org/
http://www.hindawi.com/journals/tswj/2002/704240/abs/
http://awarnach.mathstat.dal.ca/~joeb/biol3046/projects/AGE2/Antagonistic%20Pleiotropy%20Theory.htm
http://www.programmed-aging.org/theories/antagonistic_pleiotropy.html
http://poseidonsciences.scienceblog.com/files/2010/08/Aging-Scienceblog-Survivorship-curve-2006-Census.jpg
http://books.google.com/books?id=X5Po92PzOtAC&pg=PA79&lpg=PA79&dq=depletion+of+follicle+and+antagonistic+pleiotropy&source=bl&ots=Nh_xGTzbDz&sig=VrQcJUMAcI0EDKkYstp1bCwNG5M&hl=en&sa=X&ei=K_oIVOadB4PgiwK414CgDQ&ved=0CC8Q6AEwAg#v=onepage&q=depletion%20of%20follicle%20and%20antagonistic%20pleiotropy&f=false
http://www.dailymail.co.uk/news/article-2739036/Mexican-woman-Leandra-Becerra-Lumbreras-oldest-person-lived-127.html
http://www.discoverymedicine.com/Jie-Shen/2009/11/24/programmed-cell-death-and-apoptosis-in-aging-and-life-span-regulation/
http://www.nmfs.noaa.gov/gallery/images/images/photos/20110404_5589334674.jpg
http://www.mnn.com/sites/default/files/styles/featured_blog/public/METHUSELAH.jpg
http://www.smithsonianmag.com/science-nature/dont-listen-to-the-buzz-lobsters-arent-actually-immortal-88450872/?no-ist
https://www.fightaging.org/archives/2011/04/ageless-animals-the-jellyfish-edition.php
http://www.ibtimes.com/immortal-jellyfish-ageless-aspen-trees-animals-plants-who-found-fountain-youth-998646
http://www.mavericksofthemind.com/wp-content/uploads/2011/11/John-Guerin-Photo.jpg
http://www.senescence.info/telomeres_telomerase.html
http://longevity-science.org/Evolution.htm
http://www.sens.org/research/introduction-to-sens-research
http://mavericksofthemind.com/dr-aubrey-de-grey/6
http://science.time.com/2014/02/25/worlds-oldest-things/photo/08_sussman_seagrass_0910_0753_1068px/