Study comparing effects of regular metformin and metformin XR

x-no-archive: yes



Note that metformin in this study did not reduce insulin resistance.

Susan


http://www.sciencedirect.com/science...aab49e2071b12d

Both slow-release and regular-form metformin improve glycemic control
without altering plasma visfatin level in patients with type 2 diabetes
mellitus

Chang-Hsun Hsieha, Chih-Tseung Hea, Chien-Hsing Leea, Ling-Yi Wua and
Yi-Jen HungCorresponding Author Contact Information, a, E-mail The
Corresponding Author
aDivision of Endocrinology and Metabolism, Department of Internal
Medicine, Tri-Service General Hospital, Taipei, Taiwan, ROC

Received 19 December 2006; accepted 20 March 2007. Available online 6
July 2007.

Abstract

Both slow-release (SR) and regular-release (RR) metformin were effective
in the treatment of type 2 diabetes mellitus. We compare the efficacy,
safety, and effects on serum adipocytokines and inflammatory markers of
both regimens in patients with type 2 diabetes mellitus. A prospective,
randomized, double-blind study enrolled 55 patients with type 2 diabetes
mellitus, which were randomly assigned to receive either metformin SR or
RR (at a maximal dosage of 2000 mg/d for 12 weeks). Glycosylated
hemoglobin A1c (HbA1c), fasting plasma glucose, adipocytokines,
C-reactive protein, and insulin resistance and pancreatic beta-cell
function were measured before and after treatment. Significant decreases
(P < .001) in mean HbA1c and fasting plasma glucose levels were observed
in each group. However, the mean changes in HbA1c from baseline to end
point in the 2 groups were not significantly different. Changes in
metabolic parameters were similar except that a decreased total
cholesterol level was observed in the metformin RR group.

******Neither regimen treatment had any influence on insulin resistance,
but metformin RR improved beta-cell function.******

Neither regimen had an effect on serum adipocytokines or inflammatory
markers. Once-daily metformin SR was as safe and effective as metformin
RR in type 2 diabetic patients. Neither dosage form affected serum
adipocytokines and inflammatory markers.


Corresponding Author Contact InformationCorresponding author. Tel.: +886
2 87927182; fax: +886 287927183.


Metabolism
Volume 56, Issue 8, August 2007, Pages 1087-1092

The 2 tables on the page 21 of this info on Glucophage at
http://www.fda.gov/cder/foi/label/2000/21202lbl.pdf
show the reduction in gastro-disastro side effects when swtiching from
glucophage to glucophage XR. Rather a huge difference.

The part that I find puzzling is why there seems to be a similar
reduction in side effects for the placebo control group used with each
study. With regular glucophage, or met, 11.7% of the placebo group
suffered from diarrhea. But only 2.6% of the placebo group for
glucophage XR experienced diarrhea. Similar difference for nausea.
Can anyone explain why this might be?

Morris

Susan wrote:

> x-no-archive: yes
>
>
>
> Note that metformin in this study did not reduce insulin resistance.
>
> Susan
>
>
> http://www.sciencedirect.com/science...aab49e2071b12d
>
> Both slow-release and regular-form metformin improve glycemic control
> without altering plasma visfatin level in patients with type 2 diabetes
> mellitus
>
I posted the following in another newsgroup on Feb. 28. Frank

There are some indications that Nampt, Visfatin, and PBEF are synonymous
terms.

Visfatin/PBEF is a nicotinamide phosphoribosyltransferase (Nampt).
Search for nampt+nicotinamide resulted in 13 finds -
http://tinyurl.com/2zh3ck..Visfatin search resulted in 305 finds -
http://tinyurl.com/2o68vy. PBEF search resulted in 377 finds -
http://tinyurl.com/26dywz. Defined somewhat: pre–B cell
colony-enhancing factor (PBEF) a 52-kilodalton cytokine expressed in
lymphocytes. This is interesting in that in one place it is called a
cytokine and in another place an enzyme using different terminology.
Visfatin, an Adipocytokine with Proinflammatory and Immunomodulating
Properties. Adiponectin is also a biochemical secreted from the
adipocytes cells. Both of these are secreted via the portal vein from
the visceral fat into the liver.

Serum Visfatin Increases With Progressive ß-Cell Deterioration -
http://diabetes.diabetesjournals.org...ull/55/10/2871

There are overlapping ranges between humans with normal glucose
tolerance and those with type 2 diabetes. Newly diagnosed type 2
diabetics are closer to the normal range than those with longer
duration. Timothy posted an article "Nampt/PBEF/Visfatin: A regulator of
mammalian health and longevity? PMID: 16842957" in which there was a
proposal "that there is a functional equivalent of PNC1 in mammals
called Nampt (a.k.a. PBEF/Visfatin), a stress-responsive gene that would
coordinately regulate metabolism, cell defenses, and resistance to
diseases of aging." In the article above where "serum visfatin increases
with progressive ß-Cell deterioration," it was reported that type 1
diabetics have higher levels of visfatin. There have been other reports
that there isn't a correlation with tissue content and serum levels of
visfatin. Visfatin also is considered an inflammatory adipokine.

"Jefferson" <fwroy@adelphia.netxeopheno> wrote in message
news:muudnblTX-_hvQHbnZ2dnUVZ_hGdnZ2d@adelphia.com...
> Susan wrote:
>> Note that metformin in this study did not reduce insulin resistance.
>> http://www.sciencedirect.com/science...aab49e2071b12d
>> Both slow-release and regular-form metformin improve glycemic control
>> without altering plasma visfatin level in patients with type 2 diabetes
>
> I posted the following in another newsgroup on Feb. 28. Frank
>
> There are some indications that Nampt, Visfatin, and PBEF are synonymous
> terms.

> This is interesting in that in one place it is called a
> cytokine and in another place an enzyme using different terminology.

Hi Frank,
PBEF , NAMPT and visfatin are the same.One of the places to find information
on genes is the National Center For Biological Information.

Go to the NCBI at :
http://www.ncbi.nlm.nih.gov/
Open the "Search" Box in the upper left , move down , click on "Gene" to
change it from : "All Databases" to : "Gene" .
In the "for" box , next to the Search Box type : "Nampt AND Sapiens" to
exclude other organisms.
Click the "Go" button next to the "for" box

Bit elaborate , sorry Frank , but the NCBI won't let me give you the direct
URL Now you are at the latest , compiled information for the gene.The
official full name is : pre-B-cell colony enhancing factor 1 , but the gene
is also known as : PBEF; NAMPT; MGC117256; DKFZP666B131; 1110035O14Rik The
summary says : This gene encodes a protein that catalyzes the condensation
of nicotinamide with 5-phosphoribosyl-1-pyrophosphate to yield nicotinamide
mononucleotide, one step in the biosynthesis of nicotinamide adenine
dinucleotide. The protein is an adipokine that is localized to the
bloodstream and has various functions, including the promotion of vascular
smooth muscle cell maturation and inhibition of neutrophil apoptosis. It
also activates insulin receptor and has insulin-mimetic effects, lowering
blood glucose and improving insulin sensitivity. The protein is highly
expressed in visceral fat and serum levels of the protein correlate with
obesity. This gene has a pseudogene on chromosome 10. Here is also a
compilation of the latest literature where you can see that visfatin is now
aparently abandonned.

Cytokines can do their job by phorphorilating or (de-phosphorilating) other
proteins down stream in their signalling pathway so cytokines can be enzymes

hth
Gys