Monthly Archives: August 2013

Average Height Of Korean Men And Average Height Of Vietnamese Men

This is one of those posts that will go into the back of the indexes since it has no real relevance to our research. However this type of post will be used in any future type of anthropo-morphological or auxological research on asian populations.

I personally am not of the Korean or Vietnamese Ethnicity so I have no subjective biases on the research. I only present what I find and try to interpret the studies in my own way.

I refer to the study “The impact of environment on morphological and physical indexes of Vietnamese and South Korean students” – Authors: Mai Van Hung*, Sunyoung Pak based in Seoul National University in 2007.

The study basically says that if we were to divide groups of people up by the country of their origin, or the country of their ethnic origin, and we averaged out college aged young men and women we would find that South Korean ethnic based people are on average taller than Vietnamese ethnic based people.

Here are the actual numbers that are tabulated.

Height Measurements for South Korean College Students

Based on measuring 916 college aged korean men and 910 college aged korean females. When we refer to the term ‘college age’ we are talking about the age range of 20-25 years old. I personally note that fact that Korean Culture actually adds an extra year of age compared to the way American Society measures age. At the moment that a person is born, the age is counted as 1. Also, almost all South Korean young men who are of able body and in good health are mandated/obligated to serve in the Korean military for 2 years, so this means that Korean men often graduate University at the age of 24-25 while the average American male assuming that he finished his undergraduate degree in the assumed 4 year time graduates usually in the 21-22 year range. If we take into the consideration that many Koreans take a year off from their normal undergraduate years to student abroad in a European, Australian, Canadian, or American University, the average age at which the South Korean men might graduate might be 4 years later than their American counterpart. Of course, now I have digressed too far off the main point.

Average Height of Korean Men

  • Average Height for College Age Korean Men – 174.51 ± 6.15
  • Average Height for College Age Korean Women – 161.22 ± 5.18

Height Measurements for Vietnamese College Students

I personally have lived in Seoul, South Korea for the last year for business so I have more knowledge on Korean Culture than the Vietnamese culture. As for the anthropometric measurements of the young adults and college students of the country of Vietnam, I have nothing to say since I just don’t know enough about the culture and the people there, at least from a stature point of view.

Average Height of Vietnamese Men


  • Average Height for College Age Vietnamese Men – 165.76 
  • Average Height for College Age Vietnamese Women – 155.22

Just like how in the movie “The Wizard of Oz” The wizard named Oz would say “Pay no attention to the man behind the curtain” I would say something similar in this post “Pay no attention to why I decided to post about height statistics of two countries which have almost nothing in common with each other”. It’s just something I do, and I like to collect that type of mostly useless information, often to be used months or even years later in conversation, or scientific discussions.

Is there a method to my madness, and my almost obsessive fixation on average height of different groups of people around the world?

I am not sure. Maybe this is just something that I really enjoy talking about and doing research on.

I am definitely not saying that one group of people is somehow better than another group of people just because they have a larger stature on average. That is completely asinine to make such a stupid claim. I am presenting numbers that represent measured body dimensions.

These are the basic scientific points that these scientists from Seoul National University have made about human growth and height based on environmental factors.

  1. The amount of habitual physical activity has no effect on body height
  2. Daily caloric expenditure can be a major determinant of weight.
  3. Generally the basic anthropometric indexes of the North people are higher than the South people

The scientific explanation on the third claim is based on the old idea that people in regions closer to the equator, where it is hotter, would naturally evolve to have body shapes and sizes where the surface area/body volume ratio is maximized to release internal body heat generated from the millions of chemical reactions that are going on. This means that people who have ethnicities originating from countries closer to the equator would be smaller, based on the fact that as the human body gets taller, their volume increases a geometric rate based on a cubed function while the surface area of the person would increase at a squared function. That is something to be avoided evolutionary for heat releasing causes.

The last interesting facts that are noted are…

  • Average male height in Vietnamese and North Korean remains comparatively small at 5  ft 4 in (1.63 m) and 5 ft 5 in (1.65 m) respectively.
  • Currently, young North Korean males are actually significantly shorter.
  • Average male height in South Koreans are about 3 inches (8 cm) taller than their North Korean counterparts, on average…

A Special Note For People Who Read This Far Into The Post

There is nothing special to take away from this post. Some people actually develop a sort of nationalist pride for having a larger average height for their country than others. The South Koreans are a prime example of this issue, thinking they are somehow better than their neighbor Chinese or Japanese. I have met quite a few Koreans who seem to take pride in the idea that their “pure blood” race is somehow better than the other countries because they happen to have a average national height slightly more than another country.

There is an american slang term known as “Dick Measuring Contest“. It means that often men of different groups or factions start to compare themselves to other people/men and somehow get super-inflated egos over what they think is the most important thing in their own eyes, while the rest of the world thinks what they value and take pride in is trivial or useless. So don’t get trapped in a Dick Measuring Contest. Nobody is a winner. One is not better than another person just because they are taller.

Wild Olives for Height Increase?

Elaengus angustfolia is also known as silver berry or wild olives.

Toxic effects of Elaeagnus angustifolia fruit extract on chondrogenesis and osteogenesis in mouse limb buds.

“We determined the effect of Elaeagnus angustifolia extract on chondrogenesis and osteogenesis in mouse embryo limb buds in vitro and in vivo. Limb bud mesenchyme from day 12.5 embryos were used for high-density micromass cultures. Water/alcohol extract was added to culture media at 10, 100, 1000 and 10000 μg/L. For in vivo experiments, 40 pregnant mice were given 0.5, 5.0 or 50.0 mg/kg of the extract between days 8 and 18 of gestation.

In limb bud cultures 10 μg/mL of extract reduced chondrogenesis but not osteogenesis. Higher concentrations had no effect on chondrogenesis or osteogenesis. In pregnant mice 50 mg/kg of the extract significantly increased fetal femur and ossified zone length, but significantly decreased bone and cartilage volumes{How can something increase femur length but decrease bone and cartilage volume?}.

The extract had no favorable effects on chodrification or ossification and appeared to reduce chondrogenesis. This is in apparent contradiction to its empirical effects in human adults.”

“Elaeagnus angustifolia (Russian olive, Russian silverberry, Oleander), [is] a plant native to Western Asia”  How the authors prepared the extract can be gotten from the Extract Preparation section in the full study.

The authors hypothesize that the effect of the extract is due to flavinoids and antioxidants.

Both 0.5mg/kg and 50mg/kg reduced cartilage volume but only 5mg/kg and 50mg/kg increased embryo femoral bone length.  5mg/kg actually increased cartilage volume in contrast to 0.5mg/kg, 50mg/kg, and control.

“1000 µg/mL of the extract reduced cell survival. High cell density can induce the mesenchymal cells to differentiate into the chondroblasts. At 1000 µg/mL, cell density decreased; therefore the number of differentiated nodules was reduced. Lower concentrations of the extract led to a decrease in the number and the area of the nodules. Stereological study confirmed that bone and cartilage volumes were reduced by feeding the animals with a high dose of the extract. The difference in the effective concentrations in vitro and in vivo may be attributed to differences in the bioavailability of the extract components”

“the extract may exert an effect on the chondrogenic potential of mesenchymal cells through GPR30.”<-Royal jelly is also associated with GPR30.  Also, GPR30KO is also associated with longer femur length.

Wild Olives wouldn’t be the first supplement to inhibit chondrogenesis and yet increase bone length.  It would be nice to compare the ingredients to Royal Jelly to see if there are any similarities and then the direct height increasing materials could be identified.

Given the chondroinhibitory effects, it would only have potential to increase height during development and not post growth plate cessation.

Do We Use A TENS Electronic Pulse Massager or A Function Generator? – The Physics Of Electromagnetism, Waves, And Vibrations

This post is a note on resolving an issue I realized I had created almost a few minutes after I had pressed the Publish Button on the most recent post I wrote about using a pulse massager to possibly let the growth plate in still growing adolescences increase in their longitudinal growth. The post was entitled Using An Electrical Pulse Massager Physiotherapy Device To Increase Longitudinal Growth In Vivo For Open Growth Plates (Big Breakthrough)

I realized that I had made a huge mistake in not realizing that when the term frequency, or wavelength, or Herts, or Amplitude, or Intensity, there is actually almost two meanings for these things, since what I was talking about and what the Patent on Non-Invasive In Vivo Stimulation of the Growth Plates Using Capacitative Electrical Fields was talking about were two different things.

The Abstract of the Patent…

Epiphyseal growth plate stimulation in the bone of a living body is achieved by applying electrodes non-invasively to a body and supplying to said electrodes an AC signal in the range of about 2.5 to 15 volts peak-to-peak at a frequency of about 20-100 KHz.

What I realized was that what Brighton was suggesting to do was release an AC signal, and that is not what the TENS or EMS Pulse massager was doing. First I reference the Wikipedia article on Pulsed Electromagnetic Field Theory.

The Pulse Massagers that I was talking about seemed to be not releasing an AC electrical signal, but a DC signal but in a specific pattern which mimicked what a impulse function would look like. I was definitely wrong before.

There is a picture below comparing the differences between an AC Current, a DC Current, and a Pulsed Electrical Current…


Note how while the AC (or alternating current) is moving in a sinusoidal way, the Pulsating Current does not, but moves in a repeating pattern which does not drop below the Applied Current at 0.

This is my way of trying to explain the problem with my logic in the last post using an Electrical Engineering perspective. The x-y graph on the left represent the applied current over time where the x axis represents time and the y axis if for current.

The reason that the current can even go into the negatives is because when you are supplying AC Current, the electrons that are flowing down the conducting material, something like copper or iron, actually switches directions.

Based on mathematical conventions, the flow of electrons/electrical charge (aka Current) is defined by a mathematical term known as a vector, which has both a magnitude and a direction. Since the concept of current has to be defined by not only a magnitude, but also direction, when you see a ‘negative current’ that means that the direction of the flow of electrons (aka Current) is going in the opposite direction.

However I wanted to make some extremely accurate distinctions between 1. E&M Fields and Waves, 2. what Brighton is actually proposing in the patent, and 3. what I had proposed which was a mistake.

1. Elementary Electrodynamics Theory

Our bodies when broken down as much as possible turns out to be a bunch of molecules. Those molecules broken down even further through snapping the covalent, ionic, and hydrogen bones turns into atoms. Almost all atoms have at least 1 electron, and the reason that any type of chemical reaction is even possible is due to the exchange of electrons between element atoms which either have too much or too little electrons. Based on Quantum Theory the electron itself has both the properties of a particle and a wave. We can actually use mathematical tools used to describe waves to describe the behavior and movements of electrons.

What this implies is that if we really wanted to, we could say that everything has a sort of sinusoidal electrical wave of field that is generated from it. We could say that every single object does emit some type of alternating electro-magnetic signal, which means that every single object would have some type of electrical signal going through it already.

The way that all electromagnetic waves move is in a sinusoidal way, from the ones with the lowest frequency and biggest wavelength like the radio waves to gamma rays. Like the electromagnetic waves, our bodies themselves emit electromagnetic waves is a sinusoidal, alternating pattern.

However that doesn’t help us on differentiating what Brighton is talking about and what I was talking about.

2. What Brighton is actually proposing in the patent

Brighton is talking about using a function generator to send a electrical current that is of the alternating current type through the metal electrode pad.

When he talks about frequency, he is referring to how many times the flow of electrical charges or electrons reverse themselves and them reverse themselves back. The device that he reference in the patent was a

From the patent he writes the following under the section entitled DESCRIPTION OF THE PREFERRED EMBODIMENT….

FIG. 1 shows a signal frequency generator 10 which generates an AC stimulation signal having a frequency within the range of about 20-100 KHz. The waveform of the AC stimulation signal is preferably an unmodulated symmetrical sine wave having a peak-to-peak amplitude within the range of about 2.5-15 volts peak-to-peak and more preferably within the range of about 5-10 volts peak-to-peak. The frequency generator 10 can be a Wave Tech Model 148 Function Generator

3. What I had proposed which was a mistake. 

I was proposing that we use one of those TENS Pulse Massagers with the electrode pads to do the same job as the patent. They are not the same. The electrical signal that is being sent is different.

Pulse electrical signals are also measured in intensity and frequency, but the frequency is the number of impulse signals that the electrical signal sees every second. When a TENS device says that it can get upwards of 100 Hz it means that within a 1 second time frame, the electrical current was increased to a certain intensity 100 times and then decreased as well.

When you press the button to increase or decrease the Intensity, you are telling the device to increase the amplitude of the impulse signal of the electric current. The signal becomes stronger, and when graphed out in terms of current vs. time, the amplitude of the current function will multiply by a certain factor.

So I was talking about pulsed electrical signals and he was talking about alternating electrical signals, two completely different things.

Currently I have no idea what the effect of using one of those pulse massagers would be if it was applied to the skin close to the growth plate of kids who are still growing.

Would the pulse electrical signals have a similar effect as the AC signals proposed by brighton? I am not sure

Me as the amateur researcher made the mistake in thinking that a pulse massager and a function generator was the same thing.

The actual device that the Ivy League Ph. D & M.D. Orthopaedic Surgeon is suggesting is actually a Function Generator, and his proposed one was one from back in the mid 1980s. It was called a Wave Tech Model 148 Function Generator. For more information on Wave Tech, (aka Wave Tek) the company and what happened, Click Here.

You can find more information about the cost of function generators on Amazon by Click Here. Some of the models are expensive but any of the devices that can just get 60 KHz and in the range of 5-10 Volts would be good enough possibly stimulate the epiphyseal growth plates.

Adipose Tissue, Increasing Bone Size, and Interstitial Growth

The White spots within bone marrow are adipose tissue.  There are four above the arrow for instance.

Bone size and bone strength are increased in obese male adolescents.

“We recruited 51 male ObAs (10-19 years) at the entry of a residential weight-loss program and 51 healthy age-matched and 51 bone-age-matched controls. vBMD and geometric bone parameters, as well as muscle and fat area were studied at the forearm and lower leg by peripheral quantitative computed tomography. Muscle force was studied by jumping mechanography. In addition to an advanced bone maturation, differences in trabecular bone parameters (higher vBMD and larger trabecular area) and cortical bone geometry (larger cortical area and periosteal and endosteal circumference) were observed in ObAs both at the radius and tibia at different pubertal stages. After matching for bone age, all differences at the tibia, but only the difference in trabecular vBMD at the radius, remained significant. Larger muscle area and higher maximal force were found in ObAs compared with controls, as well as higher circulating free estrogen, but similar free testosterone and IGF-I levels. ObAs have larger and stronger bones at both the forearm and lower leg. The observed differences in bone parameters can be explained by a combination of advanced bone maturation, higher estrogen exposure, and greater mechanical loading resulting from a higher muscle mass and strength. ”

Obese individuals have a higher bone age than non-obese individuals until age 16.  Obese individuals had taller height than age matched controls but shorter height than bone age matched controls.

“higher values of trabecular vBMD, trabecular area, periosteal circumference, and cortical area at the different pubertal stages in the obese group. ”  So bodyfat causes increase in bone parameters outside of the growth plate.  This includes the bone age matched group and not just the age matched group.

Obese individuals had increased estrogen and leptin but similar levels of free testosterone.

What would be interesting if the fat itself did not increase various hormones and genes to cause bone growth or some kind of loading effect.  But if the fat within the bone itself caused an expansion of bone parameters.

The main difference between a growth plate and adipose tissue is that adipose tissue is disorganized as you can see in the image of the bone marrow however adipose tissue cells are huge.  So is it possible that there could be enough adipose tissue cells to cause an expansion of the bone even if they are not coordinated like a growth plate.

The effect of weight on the femur: a cross-sectional analysis.

if stresses associated with biomechanical modifications of the obese surpass the strain threshold of a bone or bony location, it is possible that discernible differences in long-bone morphology could be observed between different weight categories as a direct result of long-term, abnormal mechanical compensation.”

“The Pearson’s product-moment correlation coefficient results show no correlation between weight and stature. “<-Since only very large amounts of weight would influence stature it’s possible that effect of extreme weights are overlooked.

Mediolateral dimensions of the bone at the midshaft at the bone increased at 4 out of 5 of the sites measured in the bone.  It’s possible that other parameters were increased but not statistically significant.  Anteriorposterior dimensions were increased only at the midshaft.

Is it the adipose tissue cells themselves that increase the bone dimensions or is it a weight loading effect increasing the dimenions.  The question is why would the bone increase in size in only one dimension.  The increase in bone size being mainly in one axis is consistent with it being a weight loaded effect and not a result of internal forces from adipose tissue cells.

research has shown elongation of the proximal ML dimension of the femur in pregnant women

“As ML diameter measures resistance to ML bending, these results suggest that as weight increases, alterations to the femoral angle result in greater ML pressures, forcing the femur to adapt or risk failure.”

Reduced size-independent mechanical properties of cortical bone in high-fat diet-induced obesity.

” femora from C57BL/6 mice fed either a HFD or standard laboratory chow (Chow) were evaluated for structural changes and tested for bending strength, bending stiffness and fracture toughness. Here, we find that in young, obese, high-fat fed mice, all geometric parameters of the femoral bone, except length, are increased, but strength, bending stiffness, and fracture toughness are all reduced. This increased bone size and reduced size-independent mechanical properties suggests that obesity leads to a general reduction in bone quality despite an increase in bone quantity; yield and maximum loads, however, remained unchanged, suggesting compensatory mechanisms. We conclude that diet-induced obesity increases bone size and reduces size-independent mechanical properties of cortical bone in mice.”

Mice were fed high fat diet over 19 weeks.  4 week old mice were used.

“the HFD group showed a 34% increase in serum IGF-I concentration compared to Chow”

Cellular dynamics and tissue interactions of the dura mater during head development

“Morphogenesis of the cranial bones and sutures is dependent on tissue interactions with the dura mater, which control the size and shape of bones as well as sutural patency. Development of the brain also involves interactions with dura mater: secretion of stromal derived factor 1 (SDF-1) is a critical event in directing migration of the external granular layer precursors of the cerebellar cortex and the Cajal-Retzius (CR) cells of the cerebral cortex. The dura mater is also required for growth of the hippocampal dentate gyrus. Wnt1Cre/R26R transgenic reporter mice were used to study the origin and fates of the cells of dura mater during head development. The dura mater of mammals is derived entirely from the cranial neural crest. Beginning around neonatal day 10 (N 10), the dura mater is infiltrated by cells derived from paraxial mesoderm, which later come to predominate. Over the course of infancy, the neural crest–derived cells of the dura mater become sequestered in niche-like distribution characteristic of stem cells. Simultaneously, dura mater cells underlying the sagittal suture migrate upward into the mesodermally-derived mesenchyme separating the parietal bones. Although initially the parietal bones are formed entirely from paraxial mesoderm, the cellular composition gradually becomes chimeric and is populated mainly by neural crest–derived cells by N 30. This occurs as a consequence of osteoblastic differentiation at the dura mater interface and intravasation of neural crest–derived osteoclastic and other hematopoietic precursors. The isolated cells of the dura mater are multipotent in vitro, giving rise to osteoblasts, neuronal cells and other derivatives characteristic of cranial neural crest, possibly reflecting the multipotent nature of dura mater cells in vivo.

” neural crest cells can be found throughout the intrafrontal suture. These cells give rise to fibroblast-like mesenchymal cells in the sutures, as well as chondrocytes, osteoblasts, and osteocytes in developing bones.”

Mineralized bone is incapable of interstitial growth{this would explain why adipose tissue cells don’t cause interstitial growth, however is unmineralized bone capable of interstitial growth; unfortunately there is no citation}, and bones grow at the marginal growth sites—growth plates in long bones and sutures in the skull. ” I also couldn’t find any emails either so I can’t ask where they retrieved that conclusion from.

Further research shows that the possibility of interstitial growth is related to the the rigidity of the ECM.  So adipocytes may be capable of interstitial growth if the ECM is too rigid.

I write about the optimal stiffness of ECM for chondrocyte differentiation here.  However, the stiffness for ECM for chondrocyte differentiation may be different from that for interstital growth.  Here I mention, that the compounds that give the bone ECM it’s stiffness are Calcium, Phosphorus, and Vitmain D.  However, people with deficiencies in those three compounds do not grow taller.  Also, mentioned is that demineralized bone matrix is an effective scaffold for chondroinduction.

In conclusion, the reason that adipose cells do not cause interstitial growth in bone despite being enormous and potentially present in massive quantities is that the ECM of bone is too stiff due to the mineral content.  Although during longitudinal growth, the bone is stiff at the bony area between the top and bottom area of the growth plate.  Thus, a key factor for micro-growth plate success via induction by LSJL is to reduce bone ECM stiffness.  LSJL may do this itself by causing interstitial fluid flow and shear strain.

LSJL dincreasing interstitial fluid flow and shear strain can be supported by the histological slides presented here.  The pink area which represents the bone appears to be much less rigid(compare slides A and B).

Hydroxyapatite crystals and chondrocyte apoptosis

A recent post by Michael stated that one of the obstacles to LSJL success is that hydroxyapatite crystals have sharp edges and that could result in the damage to the cells of any microgrowth plate possibly induced by LSJL.

First, Shear Strain and Fluid Flow induced by LSJL may disrupt the crystals.  However, let’s look at the science of Hydroxyapatite crystals and cell death to chondrocytes.

Intracellular calcium oscillations in articular chondrocytes induced by basic calcium phosphate crystals lead to cartilage degradation.

“Basic calcium phosphate (BCP) crystals, including octacalcium phosphate (OCP), carbonated-apatite (CA) and hydroxyapatite (HA) crystals are associated with destructive forms of osteoarthritis.  We assessed the ability of BCP to induce changes in intracellular calcium (iCa(2+)) content and oscillations and the role of iCa(2+) in BCP-induced cartilage degradation.

Bovine articular chondrocytes (BACs) and bovine cartilage explants (BCEs) were stimulated with BCP or monosodium urate (MSU) crystals. iCa(2+) levels were determined. mRNA expression of matrix metalloproteinase 3 (MMP-3), a disintegrin and metalloprotease with thrombospondin-like motifs 4 (ADAMTS-4) and ADAMTS-5 was assessed. Glycosaminoglycan (GAG) release was measured in the supernatants of BCE cultures.

All three BCP crystals significantly increased iCa(2+) content. OCP also induced iCa(2+) oscillations. Rate of BACs displaying iCa(2+) oscillations increased over time, with a peak after 20 min of stimulation. OCP-induced iCa(2+) oscillations involved both extracellular Ca(2+) (eCa(2+)) influx and iCa(2+) stores. Indeed, OCP-induced iCa(2+) oscillations decreased rapidly in Ca(2+)-free medium. Both voltage- and non-voltage-dependent Ca(2+) channels were involved in eCa(2+) influx. BCP crystal-induced variation in iCa(2+) content was associated with BCP crystal-induced cartilage matrix degradation. iCa²(+) was not associated with OCP crystal-induced mRNA expression of MMP-3, ADAMTS-4 or ADAMTS-5.

BCP crystals can induce variation in iCa(2+) content and oscillations in articular chondrocytes. BCP crystal-induced changes in iCa(2+) content play a pivotal role in BCP catabolic effects on articular cartilage{and potentially possibly LSJL induced micro-growth plates}.”

“BCP crystal deposition in knee articular cartilage is associated with cartilage destruction, more severe clinical symptoms, and chondrocyte phenotype changes towards hypertrophy as suggested by increased expression of type X collagen and greater ability to produce BCPs in vitro”<-So the BCP crystals within the bone will encourage the chondrocytes to hypertrophy.

“BCP crystals may stimulate articular cells through two mechanisms. They can first activate cells as endocytosed or phagocytosed particles leading to intralysosomal crystal dissolution with subsequent elevation of intracellular Ca2+ levels and release of inflammatory cytokines. The other mechanism of cell activation by Ca2+ crystals involves a direct crystal–cell membrane interaction”

“In articular chondrocytes, BCP crystals induce increased DNA synthesis and cell division{this is anabolic}, IL-1β mRNA overexpression, nitric oxide and MMP-13 production, increased caspase-3 activity and chondrocyte apoptosis”

“iCa2+ was involved in OCP-induced proteoglycan degradation but not OCP-induced mRNA expression of MMP-3, ADAMTS-4 or ADAMTS-5.”

This next study relates to HA crystals and causing apoptosis in another type of cell in bone osteoblasts.

Effects of four types of hydroxyapatite nanoparticles with different nanocrystal morphologies and sizes on apoptosis in rat osteoblasts.

“Hydroxyapatite nanoparticles (nano-HAP) have been reported to cause inflammatory reactions. Here, we aimed to compare the effects of four types of nano-HAP with different nanocrystal morphologies (short rod-like, long rod-like, spherical or needle-shaped crystals) and sizes (10-20, 10-30 or 20-40 nm) on growth inhibition and apoptosis in primary cultured rat osteoblasts. The osteoblasts was treated with the four types of nano-HAP at various concentrations (20, 40, 60, 80 or 100 mg/l).  All four types of nano-HAP inhibited the growth of osteoblasts in a dose-dependent manner. These nano-HAP significantly induced apoptosis in osteoblasts. Nano-HAP with smaller specific surface areas induced lower apoptosis rates. The needle-shaped and the short rod-like particles induced greater cellular injury than the spherical and long rod-like particles, respectively. The increased apoptosis rates were accompanied by increased p53 and cytochrome c expression. nano-HAP inhibit the activity of osteoblasts and also induce the apoptosis of osteoblasts in vitro. The nano-HAP-induced apoptotic pathway is mediated by a mitochondrial-dependent pathway. Moreover, the sizes, morphologies and concentrations of nano-HAP have significant effects on the apoptotic level.”

“nano-HAP with diameters less than 100 nm can cause inflammatory reactions, especially when the particles are needle-shaped”

nano-HAP increases caspase 3 and 9 and increases Bax levels while decreasing Bcl2.  The first three being pro-apoptotic proteins and the last being anti-apoptotic.

If HA crystals affect osteoblasts it’s likely they would affect chondrocytes too.  However, osteoblasts manage to survive in bone tissue despite the existence of HA crystals.

Annexin 5 overexpression increased articular chondrocyte apoptosis induced by basic calcium phosphate crystals.

“Basic calcium phosphate (BCP) crystals (octacalcium phosphate (OCP), carbapatite (CA) and hydroxyapatite (HA)) are associated with severe forms of osteoarthritis. In advanced osteoarthritis, cartilage shows chondrocyte apoptosis, overexpression of annexin 5 (A5) and BCP crystal deposition within matrix vesicles.

Apoptosis was induced by BCP crystals, tumour necrosis factor (TNF)-alpha (20 ng/ml) and Fas ligand (20 ng/ml) in normal articular chondrocytes (control) and in A5 overexpressed chondrocytes, performed by adenovirus infection. Apoptosis was assessed by caspase 3 (Cas3) activity, and DNA fragmentation.

All BCP crystals, TNF-alpha and Fas ligand induced chondrocyte apoptosis as demonstrated by decreased cell viability and increased Cas3 activity and DNA fragmentation. TUNEL (terminal deoxyribonucleotide transferase-mediated dUTP nick end-labelling)-positive staining chondrocytes were increased by OCP (12.4 (5.2)%), CA (9.6 (2.6)%) and HA (9.2 (3.0)%) crystals and TNF-alpha (9.6 (2.4)%) stimulation compared with control (3.1 (1.9)%). BCP crystals increased Cas3 activity in a dose-dependent fashion. BCP-crystal-induced chondrocyte apoptosis was independent from TNF-alpha and interleukin-1beta pathways but required cell-crystal contact and intralysosomal crystal dissolution. Indeed, preincubation with ammonium chloride, a lysosomal inhibitor of BCP crystal dissolution[dissolved], significantly decreased BCP-crystal-induced Cas3 activity. Finally, overexpression of A5 enhanced BCP crystal- and TNF-alpha-induced chondrocyte apoptosis.

Overexpression of A5 and the presence of BCP crystals observed in advanced osteoarthritis contributed to chondrocyte apoptosis.”

So, Chondrocyte Apoptosis doesn’t occur unless the crystal is dissolved.  But it’s possible this may occur as a result of shear strain due to LSJL.    However, the apoptosis induced is not complete and wouldn’t totally inhibit micro-growth plate formation due to LSJL.

“Chondrocytes undergo apoptosis after exposure to NO or Fas ligand (Fas-L).”

“Annexins are ubiquitous proteins that can interact with acid phospholipids, membranes and cytoskeleton constituents in the presence of Ca2+. They are involved in regulating intracellular and extracellular activities such as endocytosis and exocytosis and Ca2+ fluxes. Chondrocytes produce annexins 2, 5 and 6 (A2, A5 and A6), whose levels are increased in OA cartilage. A2, A5 and A6 have been identified on matrix vesicles. A5 can form voltage-gated Ca2+ channels and mediates Ca2+ influx into matrix vesicles, which initiates extracellular mineralisation, and into cellular cytoplasm, which induces apoptosis of growth-plate chondrocytes”

” chondrocyte apoptosis induced by BCP crystals was independent from elevations in extracellular calcium and/or phosphate concentrations but required direct cell-crystal contact.”

“[BCP induced chondrocyte apoptosis requires] cell-crystal contact, crystal endocytosis and intralysosomal crystal dissolution responsible for intracellular Ca2+ elevation.

Hydroxapatite crystals require too many things to go wrong to induce apoptosis in cells to likely occur in a normal physiological environment.  And if they did they would cause apoptosis to a variety of cells not just chondrocytes so you would want to eliminate them regardless.

Thus, I do not believe that HA Crystals or BCP crystals are a hindrance of micro-growth plate formation.

Circadian Rhythm and Height Growth

Unfortunately, as of now there is no clear direction on how to manipulate the circadian clock to alter longitudinal bone growth.

Prolonged bioluminescence monitoring in mouse ex vivo bone culture revealed persistent circadian rhythms in articular cartilages and growth plates.

“we revealed a robust and extremely long-lasting circadian rhythm in ex vivo culture maintained for over six months from the femoral bone of a PERIOD2(Luciferase) mouse{How do we manipulate or re-initiate this circadian cycle for height growth?}. Furthermore, we also identified robust circadian clocks in flat bones. High- or low-magnification real-time bioluminescence microscopic imaging revealed that the robust circadian rhythms emanated from the articular cartilage and the epiphyseal cartilage within the growth plate of juvenile animals. Stimulation by forskolin or dexamethasone treatment caused type 0 phase resetting, indicating canonical entraining properties of the bone clock. Together, our findings from long-term ex vivo culture revealed that “tissue-autonomous” circadian rhythm in the articular cartilage and the growth plate of femoral bone functions for several months even in an organ culture condition, and provided a useful in vitro assay system investigating the role of the biological clock in bone formation or development.”

“the plasma PTH rhythm persisted under “constant routine” conditions where subjects were deprived of any exogenous time information, indicating that the rhythm is driven by the intrinsic circadian clock”

“At the molecular level, the circadian clock is composed of a set of clock genes forming cell-autonomous transcription/translation feedback loops; the molecular oscillators in turn drive the expression of output genes governing a variety of clock-controlled physiological processes. Specifically, two transcription factors, BMAL1 and CLOCK, heterodimerize and transactivate core clock genes such as Period genes (Per1 and Per2), Cryptochome1 (Cry1), and Rev-Erb genes (Rev-Erbα and Rev-Erbβ). Expressions of these genes (Bmal1, Per1, Per2, Cry1, Cry2, RevErbα and RevErbβ) show clear circadian rhythms with distinct peak times”

“circadian bioluminescence rhythms from long bones (proximal femoral ends and radiuses) and flat bones (calvariae and scapulae) showed similar period lengths”<-so the circadian rhythm may not be something that distinguishes between long and flat bones.

“both epiphyseal cartilage and articular cartilage in femoral trochlea  showed clear circadian rhythms for 4 days”

“expression of certain clock genes has been shown in growth plates”

” local circadian clocks in the epiphyseal cartilage may affect bone growth in juvenile animals.”

“Exogenous time cues (e.g. light) can reset internal clocks.”

“[The] phase of the bone clock [that] was strongly altered by forskolin, functions to increase intracellular cAMP levels through adenylate cyclase activation. Therefore, it is possible that in vivo circadian phase can be reset by endogenous substance(s) via the cAMP pathway in the bone. The hormone PTH increases intracellular cAMP levels via the PTH/PTHrP receptor, consequently inducing Per1 and Per2 expression through the cAMP–PKA–CREB pathway. In addition, sympathetic signaling stimulated by leptin has been shown to regulate bone remodeling in part through a β-adrenergic receptor (β-AR). The β-AR agonist isoproterenol also enhances intracellular cAMP levels and up-regulates Per1/2 and Bmal1 expression in primary mouse osteoblasts. In accordance, isoproterenol has been reported to stimulate the circadian rhythmic expression of Per1/2/3 and Bmal1 in human SaM-1 osteoblastic cells”

“DEX, synthetic glucocorticoids (GCs), was found to reset the bone circadian rhythm. GCs are secreted from the adrenal gland in a circadian manner. Although the SCN is not reset by GCs due to a lack of glucocorticoid receptor (GR) expression, circadian clocks in peripheral organs such as the liver, kidney, and heart are highly responsive to GCs. GCs are considered as internal time-cues which relay timing information within the body and synchronize the peripheral clocks, including bones, as shown here. At the molecular level, GCs bind to GR and regulate target gene expression via glucocorticoid response elements. Previous studies have identified Per1, Per2, and E4bp4 as direct targets of GRs in mice”

Forskolin alters Ca2+ and cAMP levels, I haven’t seen any studies regarding the effects of Forskolin on longitudinal bone growth.  Dexamethasone is widely known to inhibit longitudinal bone growth.  However, Dexamethasone is also known to help induce chondrogenic differentiation.