HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Jagadeeswaran, P. Search for Related Content PubMed PubMed Citation Articles by Jagadeeswaran, P.

RESPONSE TO CELLERINO ON ANNUAL KILLIFISHES

Department of Biological Sciences, University of North Texas, Denton, Texas

Address correspondence to Pudur Jagadeeswaran, Department of Biological Sciences, University of North Texas, 1510 Chestnut, Denton TX 76203. E-mail: jag{at}unt.edu

To the Editor:

In a comment on our recent article on annual fish as genetic models for aging (1), Cellerino felt that we seemed unaware of work by others on Nothobranchius as a model of rapid aging in vertebrates (2). We wish to clarify that we never claimed that we are the first to introduce Nothobranchius for studying aging. What we stated, even in the title of the article (1), was that this model is particularly well suited for studying the genetics of aging, which previous authors have not done, despite their use of Nothobranchius in aging research (3). In fact, Cellerino recognizes this fact in a recent review article (4).

Cellerino also suggests that other species of annual fish such as Nothobranchius furzeri would make superior aging models because of their much shorter life spans. Furthermore, he argues that rainfall amount in a species' natural habitat (related to longevity of the temporary ponds in which the fish breed) would be a good predictor of aging rate, and notes that N. rachovii originates from a city with annual rainfall substantially greater than the average rainfall where his preferred model, N. furzeri, lives (2). However, it is worth noting that there may be no straightforward relationship between annual rainfall and longevity in this genus, as a third species, N. orthonotus, with a similar life span to N. rachovii, lives in the same habitat in the same region as the much shorter-lived N. furzeri, according to Jubb (5). Also, Jubb describes two strains of N. furzeri that differ substantially in their life history. One exhibits a prolonged incubation period, very fast-growing fry, and highly productive adults, but after approximately 1–1.5 months, they are struck with sudden death. The second strain has an incubation time of 3 months or more, the fry grow normally, and the adults die of old age. Cellerino has focused on the short-lived strain that has sudden-death syndrome, which may or may not be related to accelerated aging. Although the cause of this sudden death is not known, it may be due to the fact that this strain may be exceptionally susceptible to stress. The strain of N. furzeri without sudden death appears to have a life span similar to N. rachovii. In the original article describing the extraordinarily short life of N. furzeri, Cellerino mentions that its shorter life span could be due to a single deleterious mutation (6). In addition, given the long incubation time in the short-lived furzeri strain, the advantage of its short-lived adulthood would be mitigated by considering its total lifetime from birth to death. A further concern with N. furzeri is that it seems extremely vulnerable to velvet disease (5). Aging studies are best carried out in the absence of infectious disease. Thus, we agree that N. furzeri might make a reasonable model of accelerated aging; however, a number of details glossed over by Cellerino (4) still need to be worked out. Perhaps most useful would be a comparative study of the two strains, which might give insight into the sudden death syndrome, but whether that syndrome will give insight into more gradual aging remains to be seen.

References

1. Herrera M, Jagadeeswaran P. Annual fish as a genetic model for aging. J Gerontol A Biol Sci Med Sci. 2004;59A:101-107.[Medline]
2. Cellerino A. On the possible use of annual killifishes as models for aging research: a comment on Herrera and Jagadeeswaran. J Gerontol A Biol Sci Med Sci. 2005;60:679.[Free Full Text]
3. Markofsky J, Milstoc M. Aging changes in the liver of the male annual cyprinodont fish, Nothobranchius guentheri. Exp Gerontol. 1979;14:11-20.[Medline]
4. Genade T, Benedetti M, Terzibasi E, Roncaglia P, Valenzano DR, Cattaneo A, Cellerino A. Annual fishes of the genus Nothobranchius as a model system for aging research. Aging Cell. 2005;4:223-233.[Medline]
5. Jubb RA. Nothobranchius furzeri. http://users.pandora.be/marc.bellemans/Furzeri_E.htm 2000.
6. Valdesalici S, Cellerino A. Extremely short lifespan in the annual fish Nothobranchius furzeri. Proc R Soc Lond B Biol Sci. 2003;270:(Suppl 2): S189-S191.

This article has been cited by other articles:

				C.-Y. Hsu, Y.-C. Chiu, W.-L. Hsu, and Y.-P. Chan Age-Related Markers Assayed at Different Developmental Stages of the Annual Fish Nothobranchius rachovii J. Gerontol. A Biol. Sci. Med. Sci., December 1, 2008; 63(12): 1267 - 1276. [Abstract] [Full Text] [PDF]

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Jagadeeswaran, P. Search for Related Content PubMed PubMed Citation Articles by Jagadeeswaran, P.