A caviott on methylcobalamin and sight

[Guest guest]

OK, I still stand on my last post, but there are several references

in the literature that mention posative effects of MeB12 and Folate

on nerves. Of course there are some very important nerves related

to sight. It's a bit of a stretch, but I wanted to point it out.

FYI: Peripheral neuropathy is a general term referring to disorders

of peripheral nerves. (from http://neurologychannel.com/neuropathy/ )

------ Two studies of interest

1: Acta Neurol Taiwan. 2005 Jun;14(2):48-54. Related Articles,

Links

Effectiveness of vitamin B12 on diabetic neuropathy: systematic

review of clinical controlled trials.

Sun Y, Lai MS, Lu CJ.

Department of Neurology, En Chu Kong Hospital, No. 399, Fuhsin Road,

San-shia, Taipei, Taiwan. sunyu@...

The clinical effectiveness of vitamin B12 and its active coenzyme

form on diabetic neuropathy is uncertain. Therefore, we searched the

English- and non-English-language literature on this topic by using

MEDLINE (Ovid, PubMed), the Cochrane Controlled Trials Register, and

related papers. We identified seven randomized controlled trials

from June 1954 to July 2004 and reviewed them for the clinical

effectiveness of vitamin B12 according to the following parameters:

Measurement scales of somatic and autonomic symptoms or signs;

vibrometer-detected thresholds of vibration perception; and,

electrophysiologic measures such as nerve conduction velocities and

evoked potentials. Three studies involved the use of vitamin B

complex (including B12) as the active drug, and four used

methylcobalamin. Two studies were of fairly good quality (Jadad

score = 3/5), and five were of poor quality (Jadad score < or =

2/5). Both the vitamin B12 combination and pure methylcobalamin had

beneficial effects on somatic symptoms, such as pain and

paresthesia. In three studies, methylcobalamin therapy improved

autonomic symptoms. Effects on vibration perception and

electrophysiological measures were not consistent. With both the

vitamin B12 combination and pure methylcobalamin, symptomatic relief

was greater than changes in electrophysiological results. However,

more high-quality, double-blind randomized controlled trials are

needed to confirm the effects of vitamin B12 on diabetic neuropathy.

Publication Types:

Review

PMID: 16008162 [PubMed - indexed for MEDLINE]

--------------------

Neurosci Lett. 1996 Dec 13;220(2):129-32. Related Articles, Links

Vitamin B12 enhances the phase-response of circadian melatonin

rhythm to a single bright light exposure in humans.

Hashimoto S, Kohsaka M, Morita N, Fukuda N, Honma S, Honma K.

Department of Physiology, Hokkaido University School of Medicine,

Sapporo, Japan.

Eight young males were subjected to a single blind cross-over test

to see the effects of vitamin B12 (methylcobalamin; VB12) on the

phase-response of the circadian melatonin rhythm to a single bright

light exposure. VB12 (0.5 mg/day) or vehicle was injected

intravenously at 1230 h for 11 days, which was followed by oral

administration (2 mg x 3/day) for 7 days. A serial blood sampling

was performed under dim light condition (less than 200 lx) and

plasma melatonin rhythm was determined before and after a single

bright light exposure (2500 lx for 3 h) at 0700 h. The melatonin

rhythm before the light exposure showed a smaller amplitude in the

VB12 trial than in the placebo. The light exposure phase-advanced

the melatonin rhythm significantly in the VB12 trail, but not in the

placebo. These findings indicate that VB12 enhances the light-

induced phase-shift in the human circadian rhythm.

Publication Types:

Clinical Trial

Controlled Clinical Trial

PMID: 8981490 [PubMed - indexed for MEDLINE]