GIVOCAL
General description
OH
HO
HO
O
P O
O
O
Ca
2+
O
P O
O
O
HO
α-isomer
Ca
2+
β-isomer
 Calcium content :19.04%
Ca/P ratio: 1.3
 Phosphorus content :14.8%
 Solubility :20 g/l in water(at 15°C)
 Organoleptic: Tasteless and odorless
 Particle size :95 % < 100 μm
 Aspect :White crystalline powder
 Water content :10 %
2
General description
Glycerophosphate anion is a vector for calcium
Physiochemical
Organoleptic
GLYCEROPHOSPHATE
Organoleptic
Main organ tissues
Cell membranes
Phospholipids
3
Absorption of Calcium salts
 Calcium is better absorbed in ionised form
 Calcium is absorbed in the small intestine
 Calcium absorption is regulated by 4 physico-chemical
parameters
 Ca salt solubility into stomach acid compartment
 Ca precipitation in the small intestine after
neutralisation by pancreatic secretion
 Ca complexation with anions (phytates, oxalates) in the
small intestine
 Digestive use coefficient : 50 –25 %
4
Solubility of Calcium salts
 Comparative studes at different pH
 3 mg/ml Ca + 2,35 mg/ml phosphate anios for salts without P
 pH adjusted with HCl or NaOH from 2 to 9
Stomach pH
Calcium lactate
2
Dicalcium phosphate
2 3
Calcium gluconate
2
Calcium glycerophosphate
2
4
5
9
Small intestine pH
Calcium glycerophosphate is soluble in all the pH scale
5
Neutralisation of acidity
by Calcium salts
A comparative study with an equivalent of 200 mg of calcium
element
Calcium source
mg
ml HCl 0,05N
Calcium carbonate
500
200
Tricalcium phosphate
515
131
Calcium lactate
1238
136
Calcium glycerophosphate 1050
96
Calcium glycerophosphate has the smallest buffer power that
means it is best solubilised in stomach
6
In vivo comportement of
Calcium salts
 Calcium carbonate
 CaCO3 is soluble at acid pH but it rapidly neutralises gastric
acidity
 CaCO3 develops a neutral area in the stomach where it
becomes insoluble
• CaCO3 is usually used as an antiacid compound
 When CaCO3 arrives in the small intestine it is neutralised
 Tricalcium phosphate (Ca3(PO4)2)
 Ca3(PO4)2 is soluble in pH < 4 but it has a high buffer power
 When pancreatic secretions enter in contact, Ca3(PO4)2
precipitates
 An excess of phosphates induces extrabone calcifications
Physiological time of metabolic interest of CaCO3 & Ca3(PO4)2 are very
brief
7
Solubility/Absorption of
Calcium salts
Calcium source
Ca
content
Calcium carbonate
40,04%
Insoluble
80% become
insoluble
Tricalcium phosphate
38,76%
Insoluble
Not bad
Calcium lactate
18,37%
Soluble at acid
pH
Good
Calcium
glycerophosphate
19,04%
Soluble at all
pH
Good
Solubility
Absorption
 Calcium carbonate has an alkaline effect and modifies the
electrolyte equilibrium. It also might induce flatulencies,
constipations, nausea.
 Tricalcium phosphate modifies the electrolyte equilibrium
 Calcium lactate & glycerophosphate are non irritant for
digestive tract
8
Phosphorus content of
Calcium salts
 The biological ratio between Ca & has to be 1 to 1,5
 Calcium glycerophosphate: Ca/P = 1,3
 Calcium carbonate: no P / Risk hypophosophatenia
 Tricalcium phosphate: Ca/P = 1,3
9
Glycerophosphate metabolism
 Glycerophosphate is an intermediate of the cellular metabolism
 Potentiality to become integrated into well-known mechanisms
 Has an esssential place into the biosynthesis of triglycerides and
phospholipids
CH2OH
OH
C
L-glycerol-3-phosphate
H
CH2
O
2 R CO ~ S.CoA (R1 and R2)
2 CoA SH

CH2O
R2
CO
O
C

CO
L--phosphatidate
O
P
Pi
CH2O
CO
R1
H
CH2
R2
P
O C
CO
R1
L-1,2-diglyceride
H
CH2OH
R3 CO ~ S.CoA
CoA SH

CH2O
R2
CO
O
C
CH2
CO
R1
Triglyceride
H
O
CO
R3
10
Glycerophosphate metabolism
 L-glycerol-3-phosphate is the main acceptor of actylated
group which are characteristics of lipidic structures.
Triglycerides
Lecithines
Cephalines
L-1,2-diglyceride
L--glycerophosphatidic acid
CDP-diacyl-glycerol
Phosphatidylglycerol
Inositides
Phosphatidyl-serine
Cardiolipids
 It is then important for the lipids storage in the adipous
tissue, for blood lipoortein structure (triglycerides and
phospholipids) or biological membranes structure
11
Glycerophosphate metabolism
Glycerophosphate acts very directly into the general ways of
glycolic metabolic regulation and cell energy
Mitochondria
 Glycerophosphate is able to become integrated into the
cellular metabolism in the way of classical reactions
12
On the nervous system
 Subjects: in vitro study protocol using rat nerve cells
 Design:
 Survival of neurons
 Differentiation of neurons cocultured with astrocytes
Defined medium + 2 mM GIVOCAL
Normal defined medium
13
On the nervous system
 Results:
 Calcium glycerophosphate enhances neuron survival in
tissue culture
 Calcium glycerophosphate has more activity in promoting
the survival & differenciation of neurons
 Astrocytes cocultured with calcium glycerophosphate were
more shaped and thus formed a greater number of
interneuronal connections
Calcium glycerophosphate stimulates the energetic way
(degradation of glucose to pyruvate through its
transofrmation into G3P)
14
Absorption of calcium on
bone tissue
 Subjects: mice
 Design:



Comparative absorption of diferent calcium salts
Diet supplemented with 0,5% calcium
Measurements of the femur resistance to fracture
 Duration: 6 weeks
Results: calcium glycerophosphate leads to a better fixation of
calcium by the femoral bone in comparison to other commonly
employed calcim salts and increases the hardness of bone
15
Gastrointestinal experiments
 TNO dynamic models are unique tools to study stability, release,
dissolution, absorption & bioconversion of nutrients, chemicals,
bioactive pharmaceutical compounds in gastrointestinal tract
 Subjects: TIM -1 (dynamic gastrointestinal model) Simulation of
gastrointestinal conditions
 Design: to determine the digestibility of calcium
glycerophosphate & calcium carbonate durign passage through
the stomach and small intestine
 Simulation dynamic conditions in gastric small intestinal tract
•
Body temperature & pH curves
•
Concentration of electrolytes
•
Activity of enzymes in the stomach & small intestine
•
Concentration of the bile salts
TNO
dynamic
model
of the
stomach
•
Kinetics
of passage
of the chime
through
the stomach
and
small intestineand small intestin (TIM-1)
•
Absorption of low molecular molecules and water
16
Gastrointestinal conditions
 Experiments performed
under the average
physiological conditions of
the gastrointestinal tract as
described for young adults
 Digested and dissolved low
molecular compounds are
dialysed continuously from
the jejunum and ileum
compartments
17
Protocols of experiments
 2 experiments were down with the same content of
calcium
 First with calcium glycerophosphate
 Second with calcium carbonate
 Sample preparations:
 Solutions at a high calcium content are miwed with artificial
saliva
 Total introduction in the gastric compartment: 300 g with
•
•
First experiment= 40 g calcium glycerophosphate
Second experiment = 19 g calcium carbonate
7,6g calcium
 Duration:
 During 3 hours 80% of the gastric contents is gradually
delivered in the small intestine
 After 5 hours 80 % of the small intestin contents are
gradulally delivered into the large intestine (sampling
bottles)
18
Protocols of experiments
 Collection of gastric content
 1 & 3 hours aliquots: G1 and G3
 Every 1-2 hours dialysing & absorbed liquids of jejunum & ileun
compartments are changed and total volumes are measured
 Dialysing & absorbed liquids in jejunum: J
 Dialysing & absorbed liquids in ileum: I
 The liquid collected at the end of the model correspond to the
liquid which goes to the colon: C
 Results analysis:
 For calcium glycerophosphate: ¹³C RMN & calcium ionic
chromatography
 For calcium carbonate : calcium ionic chromatography
19
Calcium glycerophosphate:
¹³C NMR analysis
Calcium glycerophosphate content in each
V
x1
J
x25






G1
I
x1
x300
G3
x10
C
x60
V control: 40 g
G1 first hour gastric sample: 38 g
G3 third hour gastric sample: 1 g
J jejunum dialysis sample: 16 g
17,4 g calcium glycerophosphate
I ileum dialysis sample: 1,4 g
absorbed
20
C bottle sample (large intestine): 1 g
Ionic chromatography analysis of
calcium
 Calcium content of each compartment (with calcium
glycerophosphate)




V:
G1:
G3:
J:
3,4%
3%
0,25%
0,14%
7,6 g
6,3 g
0,053 g
3,2 g
100%
83%
42%
Calcium absorbed
 I:
 C:
0,04%
0,1%
0,97 g
0,3 g
13%
4%
 Among 7,6 g of calcium initial intake, approximatively 4,17 g reach the
small intestine and are absorbed. This quantity roughly correspond to 5
times the calcium RDI
50 % of ingested calcium glycerophosphate
21
reach blood circulaton
Conclusions on Calcium
glycerophosphate
 Calcium glycerophosphate resists to in vitro
gastric passage after 3h at pH 1,5
 After gastric passage a part of calcium
glycerophosphate passes through intestine
mucous membranes during 300 minutes
 As previously supposed glycerophosphate anion
seems to have an important role in the absorption
of calcium
 Glycerophosphate is absorbed without degradations
 Glycerophosphate is absorbed in the same proportion
as calcium
22
Results with calcium carbonate
 During the mixing with artificial saliva
 Formation of gas (probably CO2)
 Increase of pH: 8,5-9,5 instead of 4
 Increase of pH in the gastric compartment
23
Results with calcium carbonate
 Calcium content of each compartment (with calcium carbonate)






V:
important sediments
G1: important sediments
G3: limpid solution
J:
limpid solution
I:
limpid solution
C:
slight sediment
0,01%
0,1%
1,1%
0,02%
0,01%
0,02%
0,03g
0,323g
0,204 g
0,677g
0,304 g
0,102 g
Non working results
-> 2,7%
-> 8,9% 0,981 g calcium
absorbed
-> 4%
Non working result
 Among 7,6 g of calcium initial intake, appreciatively 12,9 % reach the
small intestine and are absorbed.
 As previously supposed calcium carbonate is precipitated into saliva &
gastric solutions & colon
 V, G1, G3 & C measures are non significant: only soluble part is
measured
 Even if calcium carbonate was introduced in a huge quantity, 0,981 g of
calcium is absorbed
24
Glycerophosphate/Carbonate
comparison
 With the same content of calcium, glycerophophate permits a
better aborption
 7 times more in the jejunum
 4 times more in the ileum
 Nervertheless calcium carbonate permits (in the experiments) to
provide the calcium RDI (800-1000 mg)
 2 hypothesis in the case of a normal oral intake
 Absorbed % stay constant
•
•
Intake of 800 mg calcium through 4,2 g of calcium glycerophosphate = (50%) 400
mg calcium absorbed
Intake of 800 mg calcium through 2 g of calcium carbonate= (12,9 %) 103 mg
calcium absorbed
 Absorbed quantities stay constant (limite absorption level)
•
•
Intake of 1000 mg calcium through 5,2 g calcium glycerophosphate = ( 4170 mg)
1000 mg calcium absorbed
Intake of 1000 mg calcium through 2,5 g of calcium carbonate = (981 mg) 981
25
mg calcium absorbed