DR protects against methylmercury

[Guest guest]

Wow, nice! Perhaps DR helps to protect us from the little but certain

methylmercury that we may ingest eating fish...

" The results suggest that even mild calorie restriction is enough to

attenuate oxidative stress and age-related morphological changes in

skeletal muscle. Additionally, DR was effective in protecting against

methylmercury-induced pathological changes. "

Acta Neuropathol (Berl). 2004 Jul;108(1):1-9. Epub 2004 Apr 17.

Beneficial effects of mild lifelong dietary restriction on skeletal

muscle: prevention of age-related mitochondrial damage, morphological

changes, and vulnerability to a chemical toxin.

Usuki F, Yasutake A, Umehara F, Higuchi I.

Department of Clinical Medicine, National Institute for Minamata

Disease, 4058-18 Hama, 867-0008, Minamata, Japan. usuki@...

The effect of mild lifelong dietary restriction (DR) on

age-related changes was investigated in rats. Histopathological

findings were compared between 25-month-old male rats fed ad libitum

and 25-month-old male rats that were calorie restricted (80% of ad

libitum calories; protein 15%) from 9 weeks of age. DR-fed rats

retained motor activity even in old age compared with ad libitum-fed

rats. Histopathological studies on soleus muscles clarified myopathic

changes in the ad libitum-fed rats, including variations in fiber size

and an increase in the number of central nuclei. Increased

non-grouping atrophic angulated fibers were also observed. The

specimens revealed a confused arrangement of the mitochondria and

decreased mitochondrial electron transduction enzyme activities,

indicating mitochondrial insults in the ad libitum-fed rats. In

contrast, no myopathic changes, little mitochondrial insult, and fewer

angulated fibers were recognized in the DR-fed rats. The accumulations

of heme oxygenase-1, alphabeta crystallin, 8-hydroxydeoxyguanosine,

and heat shock protein 27 were recognized in ad libitum-fed rats,

indicating the attack of oxidative stress. In contrast, the

expressions of these proteins were suppressed in DR-fed rats. The

results suggest that even mild calorie restriction is enough to

attenuate oxidative stress and age-related morphological changes in

skeletal muscle. Additionally, DR was effective in protecting against

methylmercury-induced pathological changes. Small fiber size and

suppression of mitochondrial electron transduction enzyme activities

in skeletal muscle and degenerative changes in peripheral nerves were

milder in methylmercury-exposed DR-fed rats. The results indicate that

mild lifelong DR also protects skeletal muscle and peripheral nerves

against a chemically-induced form of oxidative stress.

PMID: 15095099

[Guest guest]

Hi :

It is also possible that the 15% protein is an important factor.

Fifteen percent is less than most people consume, but in this case it

was fifteen percent of calories which were, in addition, restricted

by 20% - making the protein restriction more significant.

I am hoping that the Partridge study with fruit flies due out

around year end may provide more guidance about this (about whether

restricting fat, or restricting protein is more important).

[While on the subject of fruit flies, and the possible relevance of

studies done with them to humans, I read recently that fruit flies

have ~13,000 genes while humans have ~35,000. But of the genes fruit

flies have, ~70% are also in the human genome. It is estimated, the

article said, that we have a common ancestor with fruit flies about

800 million years ago.]

So there is a half-decent chance that what works in fruit flies

**MAY** also have relevance to us.

I am hoping it turns out that fat is the macronutrient that most

needs to be restricted, because I have been used to restricting fat

intake for a very long time. If it were to turn out that protein is

the issue, then I would have to learn a lot more on the subject

before knowing how best to go about it. 's posting of a study

relating fat intake to osteoporosis is interesting. Which is another

reason why it would be nicer if it is shown that fat is the big issue.

Rodney.

>

> Wow, nice! Perhaps DR helps to protect us from the little but

certain

> methylmercury that we may ingest eating fish...

>

> " The results suggest that even mild calorie restriction is enough to

> attenuate oxidative stress and age-related morphological changes in

> skeletal muscle. Additionally, DR was effective in protecting

against

> methylmercury-induced pathological changes. "

>

> Acta Neuropathol (Berl). 2004 Jul;108(1):1-9. Epub 2004 Apr 17.

>

> Beneficial effects of mild lifelong dietary restriction on skeletal

> muscle: prevention of age-related mitochondrial damage,

morphological

> changes, and vulnerability to a chemical toxin.

>

> Usuki F, Yasutake A, Umehara F, Higuchi I.

>

> Department of Clinical Medicine, National Institute for Minamata

> Disease, 4058-18 Hama, 867-0008, Minamata, Japan. usuki@n...

>

> The effect of mild lifelong dietary restriction (DR) on

> age-related changes was investigated in rats. Histopathological

> findings were compared between 25-month-old male rats fed ad libitum

> and 25-month-old male rats that were calorie restricted (80% of ad

> libitum calories; protein 15%) from 9 weeks of age. DR-fed rats

> retained motor activity even in old age compared with ad libitum-fed

> rats. Histopathological studies on soleus muscles clarified

myopathic

> changes in the ad libitum-fed rats, including variations in fiber

size

> and an increase in the number of central nuclei. Increased

> non-grouping atrophic angulated fibers were also observed. The

> specimens revealed a confused arrangement of the mitochondria and

> decreased mitochondrial electron transduction enzyme activities,

> indicating mitochondrial insults in the ad libitum-fed rats. In

> contrast, no myopathic changes, little mitochondrial insult, and

fewer

> angulated fibers were recognized in the DR-fed rats. The

accumulations

> of heme oxygenase-1, alphabeta crystallin, 8-hydroxydeoxyguanosine,

> and heat shock protein 27 were recognized in ad libitum-fed rats,

> indicating the attack of oxidative stress. In contrast, the

> expressions of these proteins were suppressed in DR-fed rats. The

> results suggest that even mild calorie restriction is enough to

> attenuate oxidative stress and age-related morphological changes in

> skeletal muscle. Additionally, DR was effective in protecting

against

> methylmercury-induced pathological changes. Small fiber size and

> suppression of mitochondrial electron transduction enzyme activities

> in skeletal muscle and degenerative changes in peripheral nerves

were

> milder in methylmercury-exposed DR-fed rats. The results indicate

that

> mild lifelong DR also protects skeletal muscle and peripheral nerves

> against a chemically-induced form of oxidative stress.

>

> PMID: 15095099

>

[Guest guest]

Hi :

It is also possible that the 15% protein is an important factor.

Fifteen percent is less than most people consume, but in this case it

was fifteen percent of calories which were, in addition, restricted

by 20% - making the protein restriction more significant.

I am hoping that the Partridge study with fruit flies due out

around year end may provide more guidance about this (about whether

restricting fat, or restricting protein is more important).

[While on the subject of fruit flies, and the possible relevance of

studies done with them to humans, I read recently that fruit flies

have ~13,000 genes while humans have ~35,000. But of the genes fruit

flies have, ~70% are also in the human genome. It is estimated, the

article said, that we have a common ancestor with fruit flies about

800 million years ago.]

So there is a half-decent chance that what works in fruit flies

**MAY** also have relevance to us.

I am hoping it turns out that fat is the macronutrient that most

needs to be restricted, because I have been used to restricting fat

intake for a very long time. If it were to turn out that protein is

the issue, then I would have to learn a lot more on the subject

before knowing how best to go about it. 's posting of a study

relating fat intake to osteoporosis is interesting. Which is another

reason why it would be nicer if it is shown that fat is the big issue.

Rodney.

>

> Wow, nice! Perhaps DR helps to protect us from the little but

certain

> methylmercury that we may ingest eating fish...

>

> " The results suggest that even mild calorie restriction is enough to

> attenuate oxidative stress and age-related morphological changes in

> skeletal muscle. Additionally, DR was effective in protecting

against

> methylmercury-induced pathological changes. "

>

> Acta Neuropathol (Berl). 2004 Jul;108(1):1-9. Epub 2004 Apr 17.

>

> Beneficial effects of mild lifelong dietary restriction on skeletal

> muscle: prevention of age-related mitochondrial damage,

morphological

> changes, and vulnerability to a chemical toxin.

>

> Usuki F, Yasutake A, Umehara F, Higuchi I.

>

> Department of Clinical Medicine, National Institute for Minamata

> Disease, 4058-18 Hama, 867-0008, Minamata, Japan. usuki@n...

>

> The effect of mild lifelong dietary restriction (DR) on

> age-related changes was investigated in rats. Histopathological

> findings were compared between 25-month-old male rats fed ad libitum

> and 25-month-old male rats that were calorie restricted (80% of ad

> libitum calories; protein 15%) from 9 weeks of age. DR-fed rats

> retained motor activity even in old age compared with ad libitum-fed

> rats. Histopathological studies on soleus muscles clarified

myopathic

> changes in the ad libitum-fed rats, including variations in fiber

size

> and an increase in the number of central nuclei. Increased

> non-grouping atrophic angulated fibers were also observed. The

> specimens revealed a confused arrangement of the mitochondria and

> decreased mitochondrial electron transduction enzyme activities,

> indicating mitochondrial insults in the ad libitum-fed rats. In

> contrast, no myopathic changes, little mitochondrial insult, and

fewer

> angulated fibers were recognized in the DR-fed rats. The

accumulations

> of heme oxygenase-1, alphabeta crystallin, 8-hydroxydeoxyguanosine,

> and heat shock protein 27 were recognized in ad libitum-fed rats,

> indicating the attack of oxidative stress. In contrast, the

> expressions of these proteins were suppressed in DR-fed rats. The

> results suggest that even mild calorie restriction is enough to

> attenuate oxidative stress and age-related morphological changes in

> skeletal muscle. Additionally, DR was effective in protecting

against

> methylmercury-induced pathological changes. Small fiber size and

> suppression of mitochondrial electron transduction enzyme activities

> in skeletal muscle and degenerative changes in peripheral nerves

were

> milder in methylmercury-exposed DR-fed rats. The results indicate

that

> mild lifelong DR also protects skeletal muscle and peripheral nerves

> against a chemically-induced form of oxidative stress.

>

> PMID: 15095099

>