https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5278837/
This article has been cited by other articles in PMC.
Abstract
The
course of events in ischemic strokes is normally seen from a point in
which the penumbra is already in place. Since there is no known
treatment for edema reduction, mainstream medicine focuses on re-opening
the occluded vessel. Here we show that reducing the penumbra saves
neuronal units from undergoing apoptosis.
Keywords: ischemic stroke, penumbra, ozone therapy
Introduction
The
treatment and treatment outcome of ischemic brain strokes is still
unsatisfactory. Even medical associations dismiss major progress in the
current means of counteracting the disease1.
The number of totally disabled patients after ischemic stroke has
remained high over the decades at about 17% and without any sign of
alleviation.
Another point is that
mainstream medicine does not focus on the first event after stroke onset
because the first stage of inflammation, the incoming penumbra or
perifocal edema, is not identified as a target for intervention since no
medication exists.
Physiology and pathophysiology of the neuronal unit
The
neuronal unit is composed of neurons, astrocytes, and specialized
endothelial cells and pericytes building the blood brain barrier (BBB).
The microglial cells patrolling the tissue as guards belong to the wider
environment. It is common knowledge that the brain metabolizes mainly
glucose and it is taken for granted that neurons are a part of glucose
users. In 1999 Magistretti et al. reported that neurons mainly
metabolize lactate and are widely devoid of the glycolytic pathways2.
In 2004 another publication by Pellerin and Magistretti investigated
the topic further and proved the till then theoretical explanation3.
The reason is that neurons are the racehorses of our brain needing high
amounts of energy to do their work in firing and transmission of
excitations. The exocytic release of neurotransmitters and their
reuptake are highly energy-consuming processes. While astrocytes depend
on glycolysis to create pyruvate and metabolize pyruvate via acetyl-CoA
in the mitochondrial tricarbon cycle, neurons use lactate (lactate
contains only one H-atom more). In glycolysis, phosphof-ructokinase-1,
the enzyme creating fructose-1,6-diphosphate, is the limiting factor.
This enzyme is the bottleneck in glycolysis. If neurons depended on the
glycolysis to create ATP they could not work as high-speed transmitters
and would be disabled in their firing capability. Nature found the
solution in providing neurons with lactate enabling them to feed their
mitochondria located close to the neuronal spines with 'fast food',
lactate.
Even other glial cells, like
microglial cells, react promptly in case of lesions in the neuronal
tissue. After laser occlusion of a single capillary the microglial cells
occupy the area in a time as short as seven minutes4.
Ischemic stroke penumbra
From
the efficiency point of view, this division of metabolism is very
effective under physiological conditions. But it creates an 'Achilles
heel' in case of disturbance and inflammation. Any obstruction in oxygen
supply leads to ATP depletion and within eight minutes to necrosis.
Necrosis is induced in neurons by ATP deficiency close to zero,
resulting in instant cell death5. This is why we find at least a scar in the location of the first impact of ischemic stroke in most cases.
Neuronal
death sends a wave of potassium into the neighborhood depolarizing the
cells and creating the penumbra. In the penumbra zone cells can survive
since the BBB is still intact and astrocytes and glial cells still have
the means to create ATP by disabled but still functioning electron
transport chains (ETCs). The relative resistance to ischemia is based on
glycogen storage and use. In this area the cells will undergo
apoptosis. This means that ETC complex IV still works providing the
mitochondria with minimal ATP amounts enabling the cells to undergo
controlled destruction, apoptosis6.
The mitochondria still maintain a mitochondrial membrane potential
(mΔΨ) as part of their limited survival ability. Within 24 to 48 hours
the penumbra passes the stages of apoptosis. But within this time with
the special means of ATP delivery we can revitalize the area (Figure 1A-D).
A)
Intact arteria cerebri media. B) Ischemic stroke and area of first
impact. C) Widening of depolarized cells by potassium efflux. D)
Penumbra.
The ATP content (Figure 2)
in the MCA area is close to zero after occlusion and never reaches the
former level after reperfusion. The content does not equal zero since
the astrocytes still produce ATP by their ETC. Here, in the middle
cerebral artery (MCA) area the astrocytes will also develop apoptosis,
since the effector cells, the neurons passed away. In the penumbra area
we still find higher amounts of ATP for the same reason.
Yellow
bars show ATP deprivation after first impact, recovery of ATP content
depends on astrocytes using glycolysis. Green bars show ATP in the
penumbra area with ATP production continuing via ETC complex IV in
astrocytes.
If we look at the lactate content in the MCA area and penumbra we will find a vital difference (Figure 3). The MCA area produced in an animal trial by occlusion of the MCA shows an overload of lactate5.
This phenomenon mirrors the fact of surviving astrocytes with
glycolysis and ETC partially functioning and the surplus of lactate
results in the lack of surviving neurons which normally metabolizes the
substrate. A larger portion of lactate is derived from the fact, that
astrocytes themselves are no longer able to use pyruvate because of cell
membrane depolarization despite the fact that there is no lack of
oxygen in the penumbra area.
Penumbra water
Researchers
and clinicians consider penumbra edema a major problem. Still some
clinicians infuse hyperbaric glucose or mannitol solutions to get rid of
the water. If we look at the distribution of body water (Figure 4) we find that in males 40% of total body water is located intracellularly7.
From here we can assume that the edema water mainly comes from the
depolarized cells and not out of the vasa. We have good reason to assume
so, since the BBB is widely intact, most of the water is stored (40%)
inside cells, only 16% reside in the intercellular space, and edema
occurs even after total occlusion of the MCA. So the conclusion is: in
the first period after ischemia the edema water comes from the affected
cells. Later, after the end of the ap-optotic pathways, the BBB will
break down and then the edema becomes vasogenic. This view is shared by
publications telling us that 'When vascular occlusion occurs, edema
initially results in part from shifts in ions between the intracellular
and extracellular compartments; this change leads to an accumulation of
excess water within astrocytes and other cells, a change that in turn
leads to swelling'8.
On the other hand, we know by the function of aquapor-ins that these
channels transport water without allowing protons to switch membrane
side, here in the form of H3O+, and to pass their
channel. In this way aquaporins do not disturb the membrane
polarisation. The unsolved question is whether they are held in check by
phosphorylation like the ATP-dependent K+ channel. In case
of depolarization they would shed the water into the interstitium
producing the penumbra. Otherwise the different water distribution in
concert with the osmotic pressure of proteins would alter the normal
arrangement9,10.
By removing the edema water early after ischemic stroke physicians
close the door to revitalizing the stunned astrocytes, glial cells, and
neurons.
Timetable of ischemic stroke
Back
to the beginning of ischemic stroke: in most cases only a small artery
or some capillaries are involved. Occlusion of supplying arteries like
the MCA leads to death. The penumbra emerges as described above and is
still perfused by mainly intact capillaries of the BBB. Only the small
spot of first impact does not show any blood flow. The penumbra expands
until it comes to the point that the cells are able to supply themselves
with enough ATP to run their ion channels to maintain their membrane
potential. This struggle creates the outer borderline of the penumbra.
In the penumbra area the BBB is still intact during the time of
apoptosis and glucose and oxygen is delivered but not taken up by the
cell due to depolarization of the cell membranes and the stunned
metabolism. Only the small obstructed vessel shows no perfusion signs.
To restart the metabolism of the stunned cells ATP is needed. Glycolysis
starts with the input of two mol ATP (the first to create
glucose-6-phosphate and the second to create fructose-1.6-diphosphate),
and exactly these two mol of ATP per mol glucose are missing in the
penumbra to kick start metabolism (Figure 5).
Conventional mainstream medical treatment
Let
us now look at conventional treatment for brain strokes. Guidelines
limit the use of rtPA to four hours after onset of brain stroke.
Approximately
7% of the victims reach a clinic within this therapeutic window. Even
if the rtPA application reopens the occluded vessel the situation is
unchanged. The latest publication records a clinical trial with rtPA and
rtPA in combination with endovascular therapy11.
The first trial was stopped because there was no advantage of the
combined therapy. Another paper published in the same edition of NEJM
demonstrated no advantage of endovascular therapy over rtPA treatment12.
Depolarized cells in the penumbra are supplied by glucose and oxygen
even without treatment or ambitions to reopen the single occluded
vessel. But in the wake of depolarization they cannot start using the
supply. Inflammation has started in the zone behind the occlusion and in
the penumbra. The cellular environment becomes increasingly acidic with
activation of metallo-proteases which in turn will use the newly
incoming oxygen supply to create radicals after successful re-opening of
the vessel. These radicals extend the till then limited tissue damage
(undergoing apoptosis) into a larger area of necrotic debris or inflict
bleeding resulting in a much more extended scarring. This phenomenon is
well-documented and known as reperfusion injury. The therapeutic window
of four hours tries to limit the damage caused by reperfusion injury.
But this treatment does not restart the metabolism in the penumbra.
Warnings have been published by the American Society of Intensive
Medicine not to use this method at all1. Only a small
percentage of patients treated with rtPA because of the therapeutic
window seem to justify this treatment. And the evidence of induction of
bleeding should be kept in mind. The end is that in most conventionally
treated cases the area of first impact and the penumbra undergo scarring
leading to extended loss of function and disability.
Basis for explanation of ozone therapy
Ozone
is simply a small molecule which has only one intention: the oxidation
of organic chemical double bonds. Ozone gas cannot be produced enriched
to a hundred percent with ozone. It always contains oxygen, normally in
the range of up to 97%. Therefore the gas should not be directly
injected into the veins or arteries since it will disappear in ms
encountering the first cell membrane. Instead we use major
auto-hemo-therapy (MAHT) to induce intracellular ATP stocks and use
mainly the RBCs as transporters for ATP. RBCs supply and maintain the
serum with a threshold of 1 μxmol/ml blood signal undisturbed metabolism13. This ability of RBCs to disperse ATP at the area of need is used for therapy.
Here
the unsaturated fatty acids — mostly oleic acids — of the membrane
phospholipids will react in ms with the ozone molecule to build
ozonides. The presence of protecting enzymes inside and outside the cell
dismantles the ozonides (= peroxides) into compounds no longer
threatening to damage cellular structures. One of the main enzymes is
glutathione peroxidase-reductase, a member of the glutathione peroxidase
family, containing a selenium molecule inside the active center. The
glutathione peroxidase-reductase defuses ozonides with glutathione as
the substrate and proton donor into water, alcohols, and other
compounds. In this reaction the reduced glutathione is transformed into
the oxidized form. Since there are only limited amounts of glutathione
per cell available — most of the compound is found in RBCs7
— the oxidized form must be regenerated to gain reduced glutathione to
start or to be ready for the next round of detoxification.
By means of NADPH as proton donator, reduced glutathione is recycled. NADP+, the leftover of this reaction, changes the redox potential of the cell and ignites another round of regeneration. NADP+
is transformed into NADPH in the first two steps of the pentose shunt.
The limiting enzyme is glucose-6-phosphate-dehy-drogenase (G-6-PD) which
starts the pentose shunt. A lack of this enzyme more frequently found
in Asia than in Europe disables the detoxification of radicals by
glutathione peroxidase-reductase leading to hemolysis in the bottle or
blood bag in case ozone gas is used. Of course there is no absolute
G-6-PD deficiency since this would have devastating effects on all
cellular functions.
RBCs control Yin and Yang
RBCs
filled with ATP travel through the capillaries of the BBB sensing the
low ATP content (< 1 μmol/ml full blood) and start giving away their
ATP13
which is instantly used by the stunned cells. All of a sudden there is
energy available to create glucose-6-phosphate and fructose-l,
6-diphosphate to restart glycolysis. With the first pyruvate available
and the ion channels running in the cell membrane, re-polarisation of
the double layer occurs, and ATP is generated by the ETC which did not
lack oxygen but pyruvate or acetyl-CoA in the penumbra area.
ATP and effect on penumbra
The
earlier the penumbra is resupplied with ATP, the more visible is the
instant effect on the clinical picture. In the first hours after stroke
onset one can see the paralysis resolving. And the effect lasts with no
blowback. The edema shrinks and only the area of first impact, the area
of necrosis and debris from decaying neurons will be visible in MRI as a
minor scar (Figure 6D).
Outcome in a pilot study
About
15 years ago I published 45 cases of ischemic brain strokes treated
with extracorporeal administered ozone gas to full blood14.
The outcome was judged by three stages: 1) full recovery, 2) disabled
with loss of fine motor function, but able to control daily life, 3)
fully disabled (Figure 7).
Stage
1 after stroke, full recovery. Stage II, disabled but managing daily
life activities. Stage III totally disabled and immobilized.
The
Framingham Study shows over decades an outcome of 17% of the patients
in stage 3 with no signs of decline even after the introduction of rtPA
therapy. In the pilot study there was no patient enlisted in the stage 3
group. I am well aware that we cannot compare 45 patients with the high
numbers of the Framing-ham Study, but if we can reduce the outcome in
stage 3 by 5-10%, this would be a major step forward for the stroke
victims to live a decent life after ischemic stroke.
Therapeutic methodology with MAHT
Ozone
concentration and frequency of treatment: since ozone is not a
medication with a dosage/efficacy ratio we must try to produce as much
ATP inside cells, here RBCs, as possible to influence the perifocal
edema via ATP delivery by RBCs. According to the SFDA in Beijing the
highest concentration of ozone in oxygen gas is limited to 60 $$μmg/ml
to prevent the overproduction of lysophospholipids which would interrupt
membrane integrity. The effect would be hemolysis of blood cells or the
necrosis of other cells. The application of MAHT is recommended with 60
$$μmg/ml (equivalent to 3% ozone in 97 % oxygen) in 50 ml of blood. The
surplus of oxygen will stay in the supernatant and is not used for
therapeutic intervention. This lack of oxygen use prevents reperfusion
injury. The often used term oxygen-ozone therapy is therefore the wrong
expression and does not match the biochemical reactions. In principle
and with a look at the pathophysiology of the penumbra development one
extracorporeal ozone treatment is sufficient. But since ischemic stroke
patients are multimorbid six to ten treatments, once on the following
days, are recommended.
Conclusion
Because
of the described rationale, we believe that using the physiological
potential of RBCs to supply suffering tissues with ATP we can influence
the outcome after ischemic stroke. The therapeutic window is extended to
up to 48 hours until irreversible damage occurs in the sense of
extended scarring. This method is safe and without side-effects since we
use only the glycolysis to induce higher ATP levels in RBCs. Of course a
large randomized study is advisable to better evaluate this therapeutic
proposal.
No comments:
Post a Comment