Mitochondrial Filamentation

Abstract

It is reflected on the recently open possibility of new studies on Alzheimer’s disease, Late Stage Dementia, Cytoskeleton Live Dynamics and Mitochondria, afforded by the new emerging field of mitochondrial physiology bioenergetics, Mitochondrial Filamentation. To this area the author groups provided some initial efforts. The considerations emphasize the many important relationships ahead for possible future studies with many other fields. Especially with Genome Alterations and Proteonomics.

Introduction

The role of mitochondria is more and more frequently marked in cancer, neural degeneration, regeneration, and aging, together with telomeres and several other pre- and posttranscriptional aspects. ^1–6 I have made a modest contribution with respect to standard mitochondria isolation in neuromuscular diseases, heart anoxic arrest, cirrhosis, and tumoral adenomas, ^7–10 but my expertise is really in the elucidation of mechanisms of control of mitochondrial respiration and aerobic glycolysis in cancer cells. ^11–14

I am now focusing the attention of interested scientific communities on some short summaries on mitochondrial filamentation and its possible applications. ^15–18 This is an emerging new field of bioenergetic physiology and molecular pharmacology in which our group played the initiator’s role. ^19–23

Essentially, this new step forward in molecular physiology and bioenergetics has proposed, up until now, that

1. Isolating mitochondria with the minimal mechanical, thermal, and chemical stress possible, by killing the animal when sleeping and not awakening it, causes many mitochondria to show short cytoskeletal filaments anchored in the external membrane. These substructural changes deprive the mitochondria, to some extent, of respiratory control and oxidative phosphorylation giving them more adenosine triphosphatase activity and capacity to metabolize glucose or pyruvate to lactic acid if adequate glycolytic supplements are present. ^19,21

2. It was proposed, following “in vitro” and “in vivo” pilot experiments, that mitochondria underwent a recurrent cycle of filamentation and defilamentation correlated with the motor activity and light cycles of the organism probably related to the cyclic changes in the vertical gravity force. ²¹

3. It also seems from pilot experiments that agents for cancer reversal enhance mitochondrial filamentation, while some potent carcinogens induce mitochondrial defilamentation. It is also likely that inducers of neural degeneration defilament mitochondria, while agents of neural regeneration seem to increase mitochondrial filamentation. ^19–23

Thus, I would now like to share my thoughts and proposals with readers who may enquire what significance these new findings could hold in store for future studies in neural degenerative diseases and early aging. Especially, I have in mind Alzheimer’s and late-stage dementia.

Mitochondrial Fragility, Cancer, and Degenerative Diseases

I became aware of the mitochondrial research riddle that haunted my life when I arrived in Philadelphia to study single-cellular bioenergetics of cancer with Britton Chance in April 1968. ⁷ I was trying to revisit Warburg’s Theory on the Respiratory Impairment of Tumors. ²⁴ Every important investigator consulted in energy metabolism was then thinking, especially with respect to cancer ²⁵ and also for many other degenerative diseases, that the mitochondria probably possessed too much fragility to be isolated without defects or without too much fragmentation. This was possibly due to the multiple degenerative traits of the type of disease considered.

I experimented on this tenet with standard isolation of mitochondria during the years dedicated to studying neuromuscular diseases, anoxic heart, cirrhosis, rotenone tumors, and spontaneous adenomas in rats, above all. ^7–10 But I was, from the outset, convinced that such mitochondrial fragility had much to do with the enormous mechanical, thermal, and chemical stress with which they were isolated. Sir Hans Krebs and Albert Claude told me in my tiny room, adjacent to Britt’s office, that perhaps it was impossible for anybody to isolate biochemically functioning mitochondria with fewer traumas. We managed it, but it took us nearly 30 years to achieve this apparently impossible task.

Therefore, now there is surely a need to reexamine the mitochondria of normal cells as well as those isolated from diverse pathologies—with low thermal, mechanical, and chemical stress. ^15–23 The methods we developed are very straightforward. Fundamentally, they deal with diminishing the radius of the tube in the equation of differential centrifugation and isolating mitochondria very rapidly at approximately 13°C, with a somewhat basic pH, in the presence of proteolysis inhibitors.

While working with that new simple mitochondrial isolation technique, if you would allow me to make some suggestions, I consider that there are 5 things that would be necessary to arrive at a full scope of the role of oxidative stress in the biochemistry of life, disease, and death:

1. Do not pay attention to very transient free radical forms.

2. Determine levels of permanent versions with not too sensitive methods.

3. Look for derivates with cross-linking effects of DNA.

4. Try to find lesions not easily reparable.

5. Consider that cellular life, cellular alteration, or cellular death is a multifactorial phenomenon.

Genome Alterations and Proteomics

There will be thousands of years of investigative work ahead of us, I truly think, in order to define the countless varieties of genome alterations and posttranscriptional alterations in many diseases. Therefore, I reflect that the multiform advancement of normal and pathological cells of any kind has the obligation to develop diverse amplifications. It would be, anecdotally, like trying to classify the varieties of hosieries worn by the billions of human beings in the world.

I recall a conversation once I had with Sir Alexander Hadow, in London in 1964, on the variations of the lactic dehydrogenase isoenzymes in cancerous tumors. I asked him “How many of these changes have you recorded so far? Perhaps more than 20 may now have been published”. Professor Hadow replied “It could be in the hundreds were we to continue publishing this aspect which has so excited us.” I replied “the variety of cancer’s genetic expression is astounding. There could even be skin cancers from which hormones, such as insulin, could be developed. There could be a day in the future when this enormous diversity will be studied for many things such as gene alteration, growth factors and many other things.”

The most profuse gratitude should be extended to all the investigators in those so important fields such as genetics and molecular biology of cancer, neural degeneration and protection, dementia, and aging, ^{1–6,26–28} for the tremendous and intelligent efforts they have made.

I suppose that soon the role of these findings on the nature, treatment, diagnosis, and prevention of diseases will diminish somewhat to let the new priority pass.

In my modest opinion, this should be to join mitochondria and the cytoskeleton—with genes and some of the other things—which have been so effectively studied, by studying cytoskeleton live dynamics in the sense that demands knowledge in mitochondrial filamentation.

Cytoskeleton Live Dynamics and Mitochondria

Presently, cytoskeleton dynamics and mitochondria in neural degeneration have focused on alterations in axonal transport, deteriorations of the mitochondria fission–fusion processes, and mitochondrial fragmentation. ¹ I do not consider myself well versed in the cellular cytoskeleton, let alone an expert, but I sincerely believe that now, after this initial phase on the first characterization of its diverse types and numerous components, we have to progress toward a more complete live dynamic visualization.

I consider, for that aim to be achieved, that a precise following of the intact living sample of the recurring cycles of mitochondrial filamentation–defilamentation is required. That molecular physiology of mitochondria should be studied in as many cellular species as possible, in normal cells, and in several degenerative diseases. In the final analysis, our contributions to this now emerging field of mitochondrial filamentation were solely founded on isolating the mitochondria with low thermal, mechanical, and chemical trauma, at many different times of the day and night and on as many species and organs as possible, including in the livers, kidneys, and brains of mice, rats, and rabbits, respectively.

Some pilot experiments were also performed on birds, fish, vegetables, fungi, and microorganisms. I was then able to propose some recurrent cycles of the mitochondria in their external membranes, with the presentation of short radial filaments of at least 3 classes plus the formation of cones and condensation veils.

I believe that for new advances in the living molecular physiological dynamics of the filamentation–defilamentation mitochondrial cycles, the techniques of the colloidal silver in protozoa, applied in Spain some 70 years ago, could first be tried out. But this should be attempted with metals lighter than silver and on cells with a more translucent outer membrane than most amoebas possess in order to facilitate time lapse video and other noninvasive morphological techniques. I would first try colloidal tungsten carbonate on those Tetrahymena in low salinity, shallow waters that are very sensitive to light cycles in the polymerization and depolarization of their cytoskeletal arrangements.

Studies on Alzheimer

Our first proposal would, of course, be to repeat and also subject the tissues, with no visible signs of unhealthiness in the patients with these illnesses, to the study of the mitochondria. These mitochondrial isolations with the lowest thermal, mechanical, and chemical trauma would help in studying many other parallel things, among which most certainly would be genetic and molecular biology concomitants.

Let me suggest 3 things that I consider fundamental in those studies:

1. Positron emission tomography determinations of brain oxygen production should be mastered in patients and normal counterparts.

2. Postmortem studies should be done on cadavers not preserved at temperatures below 14°C.

The partial alterations of mitochondrial filamentation cycles should be done with a great attention to minor changes along the progression of the diseases.

What we have just said appears simple. But I believe that there would be work for years to come in laboratories all over the world which possess the required scientific and medical specialties. Only then, perhaps, we would begin to see the light at the end of the tunnel through which patients in hospitals or care home residents are treading.

Studies on Dementia

I think that late-stage dementia is a terminal illness brought about by a lack of physical and mental hygiene and other basic shortcomings, for example, what inhibitors of mitochondrial cerebral filamentation have the patients received involuntarily. Among these might be some of the new, and not so new, psychoactive, pharmacological agents that perhaps could be scrutinized with respect to their effect on mitochondrial filamentation.

Advanced normal senility, I think, will take hold of everyone when reaching their 130th birthday, approximately. In the human evolutionary stage, normal death would occur at that age, with the accrual of many different slow progressions of physiological causes. The onset of a normal final senility warning would possibly be when the ability to recall deep childhood memories begins to be lost, the precursor of returning to being an infant again.

The first studies, which I suggest to be made would be a detailed characterization of the mitochondrial filamentation cycles in various species of healthy animals and their spontaneous pathological differences. These studies should be done from birth up until death, wither from natural causes or from illness, so as to study the different progressions of partial filamentation of mitochondria on several tissues.

With that information in hand, say in a decade or so, experts could then focus on those same studies on humans, perhaps, using noninvasive methods. Once again we would have to broadcast something to the public domain which appears very simple but which in my opinion could give much to new research.

Preliminary Conclusion

The last 50 years have convinced me that my desire to assist people in difficulty could have conditioned my heart, and this is happening to countless others everywhere, to the degree that now I dare to publish ideas that are perhaps too ambitious for anyone. At the moment, I cannot, of course, be too specific due to industrial collaboration needed for the next course. All those involved in the enormous responsibility of these areas of investigation are much needed.