3 CR-related papers

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Hi All,

Three CR-related papers that are not pdf-available are described below.

For the first " Antioxidants do not explain the disparate longevity between mice

and

the longest-living rodent, the naked mole-rat " pretty well sum up the story.

However, actual experimental results appear not to be so simple. CRers should

not

rely on effects of CR on reactive free radical production changes?

Andziak B, O'connor TP, Buffenstein R.

Antioxidants do not explain the disparate longevity between mice and the

longest-living rodent, the naked mole-rat.

Mech Ageing Dev. 2005 Aug 5; [Epub ahead of print]

PMID: 16087218

The maximum lifespan of naked mole-rats (NMRs; Heterocephalus glaber) is greater

than that of any other rodent. These hystricognaths survive in captivity >28

years,

eight-times longer than similar-sized mice. The present study tested if NMRs

possess

superior antioxidant defenses compared to mice and if age-related interspecies

changes in antioxidants were evident. Activities of Cu/Zn superoxide dismutase

(Cu/Zn, SOD), Mn SOD, catalase and cellular glutathione peroxidase (cGPx) were

measured in livers of physiologically equivalent age-matched NMRs (30, 75 and

130

months) and CB6F1 mice (4, 12 and 18 months). In mice, Mn SOD activity increased

with age, while the activity of catalase and cGPx declined. None of the

antioxidants

changed with age in mole-rats. cGPx activity of NMRs was 70-times lower

(p<0.0001)

than in mice, and resembled that of cGPx knock-out animals. NMRs may partially

compensate for the lower cGPx when compared to mice, by having moderately higher

activities of the other antioxidants. It is nonetheless unlikely that

antioxidant

defenses are responsible for the eight-fold longevity difference between these

two

species. Maintenance of constant antioxidant defenses with age in NMRs concurs

with

previous physiological data, suggesting delayed aging in this species.

In the second paper Japanese centenarians were used to suggest that depression

and

anxiety genes possibly involved in their longevity. CRers seem to be more

relaxed,

is it not so?

Gondo Y, Hirose N, Arai Y, Yamamura K, Shimizu KI, Takayama M, Ebihara Y,

Nakazawa

S, Inagakia H, Masui Y, Kitagawa K.

Contribution of an affect-associated gene to human longevity: Prevalence of the

long-allele genotype of the serotonin transporter-linked gene in Japanese

centenarians.

Mech Ageing Dev. 2005 Aug 8; [Epub ahead of print]

PMID: 16095668

.... serotonin transporter (5HTT) ... we compared the polymorphic variation of

the

5HTT gene between 265 Japanese centenarians and control subjects. ... The

frequency

of the l/l genotype and the l allele was significantly greater in centenarians

than

in younger control subjects, particularly women. A significant effect of the

5HTT

genotype on serum albumin concentration was observed in both sexes. Although,

there

was sex optionality, the l allele may carry a longevity advantage possibly

through

behavioral mechanisms.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve & db=pubmed & dopt=Abstra\

ct & list_uids=16095668 & query_hl=34

In the third paper, alternate-day fasting is shown, although not via CR, to help

mice duck age-associated lymphomas. Also, the mitochondrial generation of

reactive

oxygen species was reduced.

Descamps O, Riondel J, Ducros V, Roussel AM.

Mitochondrial production of reactive oxygen species and incidence of

age-associated

lymphoma in OF1 mice: Effect of alternate-day fasting.

Mech Ageing Dev. 2005 Aug 25; [Epub ahead of print]

PMID: 16126250

.... Alternate fasting, that was initiated in middle age mice through a 4 month

period, reduced significantly the incidence of lymphoma (0% versus 33% for

controls). No remarkable difference was observed in the overall food consumption

between alternate-fed (AF) and ad libitum (AL) mice, suggesting that the

efficacy of

alternate fasting did not really depend on calorie restriction. A significant

decrease in the mitochondrial generation of reactive oxygen species (ROS) that

was

associated with a significant increase in spleen mitochondria SOD activity was

observed when mice were maintained on intermittent fasting. Our results suggest

that

alternate fasting could exert a beneficial antioxidant effect and a modulation

of

the oxidative stress associated with aging.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve & db=pubmed & dopt=Abstra\

ct & list_uids=16126250 & query_hl=34

Al Pater, PhD; email: old542000@...

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