Is this a Missing Link in Calcium Signalling?
Malcolm Green* Technical Director, Calinnova Ltd – Update May 2019
Billions of dollars have been invested in studying ion channels and calcium signalling over the ast 20 years or so and whilst our understanding of this has blossomed there are certainly areas still ripe for study. I am going to propose that some simple molecules that are invisible to the techniques used in current ion channel research may have profoundly important functions in the calcium signalling story. Further these molecules appear to be quite commonly deficient in animal and human diets leading to health and performance failures that could be very easily plugged by simple and cheap nutritional changes. These nutritional changes SEEM to improve calcium signalling and our working hypothesis is that they do this by facilitating the natural removal of calcium ions from the cytoplasm of electrically active cells so enabling those cells to enter the resting phase properly.
I am an outsider. When I got my honours degree in Biological Sciences in the early 1970’s nobody was thinking about calcium signalling. I am not an academic, I don’t work at a university or for a big pharmaceutical or a big nutrition company. After nearly 20 years working for large chemical companies my wife and I started an animal nutrition business focused on cage birds (budgies, canaries, parrots and birds of prey). Every month of every year what we now call chelated calcium (perhaps better described as organic calcium coordination compounds or organically complexed calcium) has been incorporated into our biggest selling products. The technology has been copied by others in that market even though we now realise we really didn’t understand it and our underlying assumption that it was simply a great source of calcium was completely flawed.
On entering the horse market in the mid 2000s it became clear that this technology was equally applicable to these large mammals and, intriguingly, had a profound role in diets that could not possibly be calcium deficient (animals grazing limestone pastures). In 2008 we started our efforts to try and understand how our products worked. This has taught us that our fundamental assumptions were wrong and that what nutritionists call chelated calcium (others may prefer the more technical terms) seems to have important roles in cellular signalling that have profound health and performance implications.
We are in the very early stages of looking at the impact of chelated calcium on dairy and beef cows and have some interesting observations in this area too.
Please note there are granted patents covering the use of these materials in horses – see the very end of the appendices.
Science and statistics
This document is an attempt to pull together the research projects we have carried out since 2008 and anecdotal evidence from independent persons in the marketplace around the world that all seems to be linked by the common thread of calcium signalling.
None of the work I am going to present here constitutes science. It is technology applied to earning a living selling products that work. The commercial world tells us that this is an important technology because people see benefits when they use it and they are prepared to spend money on it. But a tiny firm like ours* doesn’t have the resources to take the technology to a more scientifically rigorous level. One independent trial (on behaviour and performance of competition horses by University of the West of England epidemiologist Jane Williams*) shows statistical validity figures of p= < 0.003 and other trials we have conducted and have had analysed by the Royal Agricultural University show p numbers of < 0.5 for properties like muscle relaxation in horses suffering veterinary diagnosed musculo-skeletal conditions.
Hopefully some corporate and academic scientists will be excited enough to take on the challenges this line of research has to offer tough our attempts to attract interest have so far proved unrewarding.
To tickle your taste buds
Obviously calcium signalling is almost ubiquitous so if we can improve it (or more likely prevent it from failing) then benefits should be seen all over the body. Our limited resources (and marketplace opportunities) force us to restrict our field trial work to certain sectors. However we have tried to broaden the work as much as possible. These are the main areas in which we have data from trials:
Interestingly the traditional treatment for Big Head has been supplementation with limestone and DCP but when interviewed most vets in affected areas acknowledge that they still have major problems with shifting lameness that they struggle to pin down or treat. More recent reports from farriers, equine dentists, vets and experienced stockmen highlight the dramatic improvements in health and wellbeing of horses when limestone and DCP is removed and chelated calcium is supplemented.
Recently published case studies from a vet near Adelaide, Australia shows the only truly successful treatment for oxalate poisoned horses was injected calcium borogluconate (a chelate) and even horses that had responded successfully to that were later put to sleep after deteriorating on traditional calcium supplements.
As exciting is a recent (2017) report we have received of Big Head in British horses grazing chalk based pastures implying that excess ionisable calcium in the diet may be enough to upset calcium regulation and to initiate bone and soft tissue failures. This would be entirely consistent with our experience that vast quantities of chelated calcium supplements are sold to horses grazing chalk and limestone pastures and that foals raised on rich chalky pastures like the Hunter Valley of New South Wales have very high incidences of developmental bone disease.
Earlier trials in the UK showed that chelated calcium supplementation is unlikely to impact on total blood calcium but can shift the balance between ionised calcium (iCa) and complexed calcium often lowering iCa whilst simultaneously improving behaviour and other functions.
More recent reports link high oxalate pastures (Central Queensland) to calving difficulties in heifers. These animals simply seem to lack the muscle function to push the calf out. When assisted pulling the calf is really easy.
Hypotheses about the physiology and cellular biochemistry
The main research methods used on ion channels and calcium signalling seem to rely on the electrical charge of the metal ions. This applies to the patch clamp method or fluorescence techniques. The “chelated calcium” molecules we are dealing with are much larger, very stable and carry no electrical charge. Although recognised for decades as normal components of blood and presumably inter and intra cellular fluids they are invisible to the techniques used in ion research. However our work suggests that chelated calcium molecules are measured as part of the calcium homeostatic process. This means that while protein bound calcium seems to be independent of calcium regulation both ionised calcium and chelated calcium are counted together. That suggests that both these forms of calcium have important functions and it also creates the possibility that high ionisable calcium diets may “out-compete” chelates and that “bad chelates” (like calcium oxalate) may also exclude the good chelates (like gluconate, citrate or amino acid salts). This would explain why we developed this technology in horses grazing high ionisable calcium pastures (on the limestone of the Cotswolds in the West Country of England) despite it being counter-intuitive to apply a calcium supplement to such animals.
So let us start with the blood information that clients and their vets have been kind enough to share with us. We have quite a lot of data from horses. All the horse blood information I will present here are on horses that came to us with behavioural and often related performance problems as we were selling chelated calcium as what the horse nutrition industry would call a calmer (any researchers dealing with humans with ADHD may be interested in this). In all cases triallists reported improvements in behaviour that coincided with chelated calcium supplementation though this story is complicated by the negative effects on behaviour of the huge amounts of magnesium used in horse diets (mostly as a sedating calmer)*. However in order to obtain good behaviour from horses we have concluded that two conditions need to be met:
When these are achieved all the horses in the trials described showed improved behaviour and performance as reported by their riders. Obviously in the real world many other factors impact on horse behaviour such as pain (ulcers, saddle fitting etc).
When we started to conduct these trials (late 2011) we were under the belief (from veterinary text books) that the only blood calcium that mattered was ionised calcium so we assumed that horses that improved when given our supplement would show increases in iCa. We were wrong. All the horses showed very steady Total Serum Calcium but quite variable iCa. In fact the iCa level dropped in more horses than it rose. The changes shown here occurred within one month of chelated calcium supplementation at the “loading dose” we have always used since 1994 in birds and since 2009 in horses.
When horses’ blood protein (especially albumin) levels rise or fall so does their total blood calcium. This implies that the protein bound calcium is not rigorously controlled as part of calcium homeostasis. However the notion that adding chelated calcium to the diet can actually decrease blood iCa suggests that the chelated calcium is part of the regulatory process. Indeed it could be considered as having to “compete” with iCa for space. Evolution has had millions of years to work on calcium regulation and it seems likely that if iCa was really all that mattered it would be much better regulated than our trials suggest. If chelated calcium is included in the homeostatic process that implies that it too has a role in nature.
I have been really surprised how little work seems to have been done on calcium regulation and the calcium regulatory protein* but it is noticeable that there are organic compounds (drugs) capable of influencing it. None of these compounds seem to bear any relationship to the chelating materials we use so don’t provide any guidance about how say calcium citrate or calcium gluconate might be measured in the body.
If we take the notion that calcium chelates and ionised calcium “compete” for space in the blood it explains how horses on high calcium diets may benefit from chelated calcium supplements. This has also been supported by our Australian work were horses with calcium oxalate poisoning recovered better on chelated calcium supplements if the “traditional” limestone and calcium phosphate supplements were withdrawn. And they also had spare calcium carbonate to excrete in their urine despite this reduction in calcium input.
Our desk research has only discovered one mechanism by which chelated calcium is selectively moved around cells and that is through voltage dependant anion channels (VDACs). VDACs have a number of characteristics that make them interesting:
This section on VDACs may be short but equally it may be the most important idea in this document. Or do all you ion channel experts have better ideas?
I am getting well out of my depth here but please bear with me. For nearly 20 years we have made a simple set of connected observations:
I recently read an article that suggested that humans with Chronic Fatigue Syndrome (CFS) and Myalgic Encephalomyelitis (ME) often had their symptoms appear after some sort of trauma. These symptoms are then notoriously difficult to get rid of.
It would appear that following a shock the function or TRPM3 channels is affected – or is it that the gene itself is impacted or maybe humans have versions of the TRPM3 gene that, when switched on or off may cause CFS or ME? Regardless the TRPM3 receptor seems to be largely involved in the removal of calcium ions from the cell cytoplasm and pumping them into store in the Endoplasmic Reticulum. And this occurs in cells all over the body. Is this a coincidence or does it relate to our hypothesis – see below – that chelated calcium is involved in removing Ca++ from the cytoplasm.
What other ion channels may have a use for chelated calcium molecules?
Tying up and calcium clearance
The other reason we believe that chelated calcium may help with calcium ion removal is “Tying Up” in horses. This condition is mostly caused by a failure to remove the calcium ions from the cytoplasm of the muscle cells. These cells remain contracted as a result. The condition varies from a completely locked muscle in spasm to simply shortened gait length as the relaxation process is impaired.
With two exceptions (both of which occurred during a “power-loading” process) even horses with a history of tying up do not do so when on chelated calcium supplements. Plenty of anecdotal reports and our work on horses with Kissing Spines support the improvement in muscle relaxation and stride length in horses ranging from dressage to racing.
A final thought about the science
Clearly billions of dollars has been spent on ion channel research but two observations have to be made:
Our take on calcium homeostasis
I have been really surprised how little research has gone into this crucial topic. It is as if, just because we have identified a bunch of hormones, we don’t need to look much deeper. Our limited work makes it really clear that iCa is far from the only calcium counted as part of the homeostatic system. If other stuff is measured there must be a reason – it isn’t an accident that has lasted for billions of years of evolution.
I have tried to produce a diagrammatic illustration of how we believe the calcium homeostatic system works.
Let’s start by looking at what happens when the level of protein (particularly albumin) changes. Many proteins in the blood have calcium bound to them. When blood protein levels rise or fall (generally as a result of illness) the Total Blood Calcium level rises and falls as well. This demonstrates that this protein bound calcium is not regulated by the homeostatic process:
When ionised blood calcium (iCa) levels rise or fall the Total Blood Calcium remains unchanged. That’s a surprise – after all we all thought iCa was the only thing that matters!! iCa is easy to measure and easy to control so the fact that such changes can easily be initiated by dietary change is a real surprise.
This tells us that iCa is not the only form of calcium that is controlled by the homeostatic process. So if the iCa increases the organic and/or inorganic complexed component must decrease. Of course there is a chicken and egg question to be asked here.
Conversely supplementing with chelated calcium can reverse that effect. So the homeostatic process is measuring and regulating the combination of iCa and more complex, uncharged molecules where the calcium entity is firmly attached to a ligand. We have never tested inorganic complexed calcium molecules so we don’t know if organic and inorganic molecules are both counted or not. Over to you scientists for that one.
There is one very important layer of complexity and that comes about because not all the complexed molecules seem to have the same functionality. We know that calcium oxalate effectively poisons horses and the same may be true of other organic and/or inorganic calcium salts. So I will introduce the notion of good and bad calcium chelates. In this chart I have assumed the bad chelates compete only with the good chelates but it is equally likely that iCa levels would drop in animals grazing, for example, high oxalate pastures.
And we also have no idea why calcium oxalate is a poison – is it because it is so small or because the calcium ion is bound to just one ligand not multiple ligands or something else?
We can measure Total Blood Calcium and we can measure iCa but we have no measure of organic, inorganic, good or bad complexed calcium. I am really hoping that a veterinary or human laboratory somewhere will take on this challenge.
I have not found any references to regulating anything other than “calcium” or “calcium ions” or “Ca++” when looking through the literature. However I don’t have good literature access and hope that I can stimulate someone to look for any studies on the regulation of complexed calcium molecules.
Similarly there seems to be very little study of the calcium sensing protein yet there are large, organic molecules (drugs) that are capable of influencing it. It would be fascinating to know what impact molecules like calcium citrate and calcium gluconate have on the calcium sensing process.
More detail on our trials and case studies
Our first trial, in 2008 simply took horses with difficult behaviour and either added a variety of different chelated calcium molecules to the diet or, as a control, calcium carbonate at a much higher level of calcium.
None of the calcium carbonate horses showed any behaviour changes but all except one of the horses given chelated calcium (whatever the ligand) showed improvements. The one that deteriorated almost certainly had a large amount of magnesium in its diet as we now know just how much that can impair brain function. These simple trials formed the basis of our primary patent.
Our second trial again used horses with difficult behaviour and fed them a product that contained both calcium and magnesium. This shows our ignorance then of the negative impact of magnesium – it was and remains the most common (sedating) “calmer” on the market worldwide.
Because we assumed that chelated calcium was simply a better source of the only active calcium – iCa, we didn’t even measure Total Blood Calcium. When the results came through we were taken aback as not only did iCa tend to fall but so did magnesium. Somehow chelated calcium seems to help regulate blood magnesium though generally not as far as we would like. Those interested in the magnesium component of this story should contact us for more detail or watch our main YouTube Magnesium video: https://www.youtube.com/watch?v=7JKe4Bvh4E4
So in our third trial we used only chelated calcium (no magnesium) and we measured Total Blood Calcium, protein, albumin and iCa. The Total results show that (as protein figures were pretty stable) the Total Blood Calcium is also stable even when iCa is changing significantly. These charts also highlight why a blood test for organic and inorganic complexed calcium would be useful.
A little aside here about what level of iCa a horse needs. The main text books I have viewed say 55% of the blood calcium should be ionised. The horse that ended the trial with the lowest iCa reading was an Arab horse that competed in endurance. Living on the Shropshire/Wales border it grazed the lowest calcium soils in Britain so an initial low iCa is really no surprise (now we realise iCa is not tightly controlled). It was in the trial because its vet recognised that it had major behavioural issues and it often struggled to pass the vet checks during competitions (it suffered Sychronous Diaphramatic Flutter and heart and respiration rates that didn’t fall adequately quickly). In the “after” condition in the chart above this horse finished the Endurance World Championships as the best British horse (12th overall). Just a month on chelated calcium had corrected its metabolic and behavioural issues simultaneously. iCa was 46% of total blood calcium – and you will find vet text books in other parts of the world that suggest the “right figure” should be 47%. Regardless of what is correct this supports our oxalate work that says that even horses with impaired bone density do not necessarily benefit from adding limestone and DCP. Indeed those additives may have anti-nutritional effects.
And that brings us to blood trials on horses with oxalate poisoning.
Oxalate poisoning is a huge and drastically under recognised condition. It is best seen in Australia with horses grazing pastures “improved” by the sowing of exotic tropical grasses like buffel, setaria, green panic and kikuyu. Buffel covers millions of acres of extensive beef cattle country in Australia and South America and probably (I haven’t investigated) North America too. Setaria has been used for dairy farming
Species like kikuyu create merry hell even further south and are common in temperate and semi-tropical climates and, of course, in their region of origin – East Africa.
Oxalate poisoning mainly affects horses though reports of weak bones, problems calving (weak muscles) and even neuromuscular failures described as “milk fever symptoms” – even in weaning bullocks which clearly can’t lactate but can suffer from neurological failures! All of these have reportedly resulted in stock deaths
In horses the problems are often more severe. Some big cattle stations routinely shoot horses over 12 years old because they assume they will be affected. Others feed them expensive imported hay to avoid them consuming calcium oxalate. Most feed limestone and DCP because they have been assured that these horses simply cannot absorb calcium oxalate and so become calcium deficient. If only it was that simple. Symptoms vary seasonally (oxalate levels are higher in fresh growing grass so peak after rain). The most well-known symptom is “Big Head” which is simply enlargement of the facial bones, often lumps and bumps and a very broad nose. Normally these bones are assumed to be very soft but when you get into the field you also get reports of hard nodules and even mineral deposits in the glands of the neck. These apparent opposite symptoms are consistent with observations reported in other cases of chelated calcium deficiency much earlier in this document.
We estimate that these skeletal deformities only show in perhaps 5% of oxalate affected horses. Demineralised bones and the reverse, bone spurs, ringbone etc., are far harder to see unless they occur on leg joints or along the long bones of the legs. Yet we have plenty of reports of horses with almost completely demineralised cannon bones, pelvic bones and even the spine.
Because the disease has been labelled Big Head the 95% of horses that don’t show that symptom are presumed to be alright. In other words the DCP and limestone supplements are credited with preventing the problem. Yet there are huge numbers of horses with major behavioural problems. Hormonal issues from EMS and laminitis to a failure of mares to cycle normally and hence conceive are very common and vets are constantly chasing shifting lameness around horses and struggling to diagnose a cause or effect a cure.
The veterinary name for the disease is equally misleading – Nutritional Secondary Hyper Para Thyroidism. Our trials showed that whilst two out of 5 horses had elevated PTH, one relied on Calcitonin and even more were using 25 hydroxyvitamin D. None of these three hormone tests are available to Australian equine vets. We used human hospitals for calcitonin and Vit D and in 2012 we could get PTH from a vet lab – but that service is no longer available and samples have to be sent to America.
All three elevated hormones normalised during the first 1-2 months of the chelated calcium supplementation except the horse using calcitonin whose levels dropped much slower. Despite that his severe aggression symptoms, facial deformations and shifting lameness all resolved in about 2 months.
We tested Total Calcium, protein, albumin, iCa, Mg, Na and K. Apart from the two lowest total calcium horses going up there was no obvious pattern to any of those mineral blood results.
The hormone results were dramatic as was the relief of symptoms.
The other telling effect was that horses that appeared to be retaining as much calcium as possible in any form before the trial, started to pee out calcium oxalate and calcium carbonate crystals.
And the most important fact about this trail is that part of the regime was the removal of all limestone and DCP and magnesium supplementation. So we dramatically reduced calcium inputs yet remineralisation occurred. This is why we do not accept that oxalate poisoning causes calcium deficiency. Even low calcium diets are fine when adequate chelated calcium is there to regulate the processes properly.
A further note is that the stability constants of chelates vary – though they are all far more stable than calcium carbonate and calcium phosphates. The chelate we used in this trial more stable than calcium oxalate so even less likely to donate its calcium ions to bone or blood. Stability constants, association and dissociation constants seem to have gone out of fashion but they seem important in this case.
There has been very little published research on Big Head or oxalates in horses and all that is out there is predicated on the poor absorption/deficiency assumption. This has never been tested except in our trial. Only one other paper (Herbert et al 2016) mentions chelates and in those case studies the only reliable treatment was the injection of calcium borogluconate (a chelate). Horses responded positively to this treatment in minutes yet were always “maintained” on DCP/limestone. Some were later put down despite previous success with the injected chelate.
So there appears to be no scientific evidence that ionisable supplements work and our trials and the Herbert case studies support the use of chelated calcium.
Equally importantly the marketplace is currently very excited about chelated calcium as in Central Queensland a significant number of people have now used chelated calcium with astounding success including vets, farriers, equine dentists, equine chiropractors, competitive camp drafters and working musterers. The cattle stations are so excited about the impact on their horses that many are looking to see what chelated calcium can do for their cattle with initial interest in calving heifers and cow and heifer conception rates.
Big Head (and other conditions) without oxalates
In the good old days Big Head had other names including Millers Disease and Bran Disease because they occurred in horses on high grain diets. Horses fed these high phosphorus, low calcium diets seemed to produce genuine calcium deficiency and the associated facial bone symptoms. It is probably this experience that initially made the oxalate/deficiency hypothesis so attractive. I have never experienced this cause of Big Head as diets like that are thankfully far less common. We still feed far too much starch to horses and they suffer from ulcers, cholic and insulin resistance as a result but bran disease, if there, is not being reported.
Our blood hypothesis suggests that high limestone/DCP diets should reduce blood chelated calcium levels and lead to the shifting lameness and behavioural issues and perhaps, in extreme cases to Big Head. All the anecdotal evidence points to exactly that and is now spreading into dairy cattle. So while Bran disease may create calcium deficiency we are suggesting that a simple overload of ionisable calcium can also create problems by reducing chelated calcium levels in body fluids.
All of our original work and product development was carried out on horses grazing Cotswold limestone. The focus was on behaviour and we now have thousands of horses in the UK and elsewhere improving behaviour using chelated calcium. Probably the majority are grazing high calcium pastures but as the Arab endurance story above shows low calcium soils also produce behavioural issues that chelated calcium resolves. This is why we need tests for the various organic and inorganic complexes.
More recently, as news of our work seeps out we have had reports of Big Head on high calcium soils. The first was in Westerham, Kent on the North Downs and he resolved with chelated calcium. Just in early May 2017 we heard of eight horses that annually get Big Head symptoms (the vet was treating for sinus infections). These horses are grazing a small patch of very chalky soil in Hertfordshire. The owner unilaterally gave these horses chelated calcium, all started to improve. She then switched to limestone and all deteriorated in two days and later improved again on chelated calcium.
We have a report of a horse on the Epsom Downs that, when given calcium carbonate and magnesium oxide as part of an ulcer treatment regime developed significant muscle tension along the topline.
Near Warrnambool in Victoria (sand over limestone or just limestone) an organic dairy farmer has stopped feeding his cation/anion acidifying diet to pre-calving cattle and instead “loaded” them with our standard chelated calcium protocol and cut milk fever rates toabsolutely zero and the whole herd has now calved. We are hoping we will see improved conception rates following this less stressful and calcium depleting approach to milk fever prevention.
Independent behaviour research
Jane Williams, an epidemiologist from the University of the West of England, conducted a study of horse behaviour, performance and trainability with chelated calcium supplements and the outcomes were published as a poster at the International Society for Equitation Science Conference in 2015:
A short note on magnesium
Magnesium has profound negative effects on horse behaviour presumably by blocking NMDA channels and antagonising calcium receptors inside cells. This is a huge topic all of its own and not a subject in this document though the author will be delighted to share the published and unpublished information on this topic. In the real world it is clear that excessive supplementation with magnesium is capable of preventing many of the benefits of chelated calcium. This supports the notion that chelated calcium has a function in calcium signalling.
Malcolm Green – Biography
Born 24 April 1953
Dulwich College, London
The University of East Anglia, Norwich. BSc (Hons) Biological Sciences
The University of New England, Armidale, Australia, Grad Dip Agricultural Economics
ICI Paints Division, UK
Exxon Chemical Australia Ltd
Calinnova Ltd (1994 - present) – 22 years in animal nutrition specialising in cage and aviary birds and horses (from 2005).
Badminton (played for Norfolk).
Sailing (Qualified for four Laser World Championships and represented GB at one. Now sails a small cruiser on the Mediterranean).
Horse riding – but rubbish at it.
Bred pedigree Limousin cattle including Supreme Limousin Exhibit at the 1994 Royal Sydney Show.
Great Britain 2468675