There is a continuing discussion as to which is worse -
long-term high exposure to moderately elevated blood glucose
levels or short-term much higher spikes. Most of the
discussion I've read here on the subject tend to focus on
vascular and cardio damage. While searching for something
else I came across this paper on renal aspects.
I won't pretend to be able to follow it all, so I'll be
interested to hear the comments by our scientists.
Here is how I understand it as a layman. I may be totally
wrong so please correct me if I am.
Segments of normal renal cortex from nine renally healthy
non-diabetic subjects were treated in the laboratory by
exposure to four different "glucose conditions."
1. One glucose condition was the control and was subjected
to 72 hours constant exposure to 5mM(90mg/dl).
2. The second was exposed to 72 hours of 15mM(270).
3. The third "fluctuating glucose" was exposed to a cycle of
two hours at 15(270) followed by three hours at 5(90). This
was repeated three times daily, then incubated at 5(90)
overnight and the cycle repeated for two more days. In this
fluctuating protocol, the cells were exposed to a total of
180 mM glucose over a 24-h period compared with 120 mM under
control conditions.
4. The fourth or "moderately elevated glucose" involved
constant exposure to 7.5 mM. This condition gave the same
total glucose load over 24 h as the fluctuating condition
(180 mM) but delivered it in a constant manner.
There was a separate control to check on the experimental
methods.
Their results, in brief:
"In summary, this study provides evidence that short-term
repeated exposure to high-glucose conditions amplifies the
adverse cellular responses compared with cells exposed to
the same glucose load or constantly high levels of glucose.
These effects are shown to be mediated through both
osmotically and nonosmotically induced mechanisms. These
results are likely to have important implications for the
monitoring and treatment strategies implemented in patients
with diabetes mellitus."
If you read the detail, the surprise to me was that the
fluctuating 5-15 mM levels were actually worse for some
results than continuous high 15mM levels; they were
definitely worse than steady 7.5 mM . Maybe I'm reading it
wrong. However, despite it's limitations it's one of the few
papers indicating that short term high spikes may be causing
damage, in this case to kidneys.
Cheers, Alan, T2, Australia.
d&e,
metformin 1500mg, ezetrol 10mg
Everything in Moderation - Except Laughter.
--
http://loraldiabetes.blogspot.com/ http://loraltravel.blogspot.com/
latest: Slovenia
Short-term peaks in glucose promote renal fibrogenesis 
Linear Mode
