VITAMIN D, CALCIUM, PHOSPHATE METABOLISM

1. VITAMIN D,
CALCIUM,
PHOSPHATE
METABOLISM

2. CONTENTS
1. INTRODUCTION
2. VITAMIN D
INTRODUCTION
SYNTHESIS AND REGULATION
BIOCHEMICAL FUNCTIONS
3. CALCIUM AND PHOSPHATE
INTRODUCTION
ROLE
SOURCE IN DIET
ABSORPTION & EXCRETION
REGULATION
4. APPLIED ASPECT
5. CONCLUSION
6. REFERENCES

3. INTRODUCTION
• "vitamin" comes from the Greek word “vita”, means
"life".
• Reqd in small quantities.
• FUNCTIONS:
(a) Resistance of the body against diseases.
(b) Stimulate and give strength to digestive and
nervous system.
(c) Convert food into energy, and repair cellular
damage.
(d) Help strengthen bones, heal wounds, and
immune system.
VITAMINS:

5. MINERALS:
Macro Elements
Calcium
Magnesium
Phosphorus
Sodium
Potassium
Chloride
Sulfur
Trace Elements
Iron
Iodine
Copper
Manganese
Zinc
Molybdenum
Selenium
Fluoride
• Calcification of bone
• Blood coagulation
• Neuromuscular irritability
• Acid-base equilibrium
• Fluid & osmotic balance
Inorganic components in our diet.

7.  Fat soluble secosteriods.
 Vitamin D2 - ergosterol – in plants
 Vitamin D3 – 7-dehydrocholesterol – in animals
 Sunshine vitamin.
INTRODUCTION
PROVITAMINS
 Daily requirement - 200 IU or 5 µg
400 IU or 10 µg

8. SYNTHESIS
• Cholecalciferol is hydroxylated at 25th
position to 25-hydroxycholecalciferol by
specific 25-hydroxylase present in liver.
• Kidney possesses a specific enzyme, 25-
hydroxycholecalciferol 1-hydroxylase at
position 1 to produce 1,25-DHCC.

9. REGULATION
i. Plasma phosphorus
level
ii. Plasma calcium level

10. BIOCHEMICAL FUNCTIONS
1. Action of calcitriol on the intestine :
• Calcitriol cytosolic receptor calcitriol
receptor complex.
• Increased formation of Calbindin, a calcium binding protein.
• This protein increases the calcium uptake by the intestine.

11. 2. Action of calcitriol on the bone :
• Promotes mineralization of epiphyseal cartilage & osteoid matrix.
• Stimulates synthesis of osteocalcin and activity of alkaline phosphatase.
• Along with PTH, increases mobilization.

12. 3. Action of calcitriol on the kidney :
• Stimulates reabsorption of Calcium &
Phosphorus at Distal renal tubular level.
• Calcitriol is also minimizes the excretion of
calcium and phosphate.

13. Vitamin D deficiency: • hypoplasia of enamel
• atrophy of salivary glands
• facilitates development of dental
caries
• compromise osseous healing
• increased gingival inflammation
• tooth loss
• Will not produce cathecidin
DENTAL IMPLICATIONS

15. CALCIUM
Adult human contains 1.0 – 1.5kg.
99% - bones & teeth
Normal plasma level: 9.0 – 11.0mg/100ml.
Ionized (50%)
Plasma calcium exists: Protein Bound (40%)
Complexed (5 – 10%)

16. PHOSPHATE
 In human body Phosphorus is present as phosphates
 Adult body contains: 0.7 – 1.0kg.
 80-85% in bones and teeth.
 Normal plasma level – 4.5 – 6.0mg/100ml infants.
3.0 – 4.0mg/100ml adults.
free inorganic (40%)
 Plasma phosphate exist: phosphate complexed (50%)
protein bound (10%)

17. ROLE OF CALCIUM IN BODY
 Blood coagulation.
 Action on heart.
 Secretory activity of glands.
 Release of certain hormones
like insulin, vasopressin, PTH.

18.  Key constituent of bone and teeth.
 Regulates blood pH.
 Forms phospholipids, phosphoproteins &
nucleic acid.
 Formation and utilization of high energy
phosphate compounds.
 Phosphorylation.
ROLE OF PHOSPHATE

19. Best source:
Hard cheese
Milk
Dark green leafy
vegetables
Good source:
Broccoli
Baked beans
Dried legumes
Dried figs
Fair source:
String beans
Eggs
Bread
RDA OF CALCIUM:
Averageadult-800mg/day
Infants:<1yr - 360-540mg
1-10yr - 800mg
11-18yr -1200mg
Duringpregnancy&lactation-1200mg/ day
SOURCES OF CALCIUM

20. Rich source
Milk
Fish
Poultry
Eggs
Moderate sources
Cereals
Pulses
Nuts
Legumes
Meat
RDA OF PHOSPHATES
Adults-800-1200mg/day
Infants-240mg/day
During pregnancy & lactation-1200mg/ day
SOURCES OF PHOSPHATE

21. • Calcium is absorbed from the small intestine.
• About 70% - 90% of daily intake of calcium is excreted.
• Phosphate is absorbed mainly from jejunum.
• Influenced by Vit D, Ratio of Ca:P & PTH.
• Almost 2/3rd of the total phosphate is excreted in the urine.
CALCIUM & PHOSPHATE ABSORPTION
AND EXCREATION

22. FACTORS AFFECTING CALCIUM ABSORPTION
FACTORS INCREASING
ABSORPTION
FACTORS DECREASING ABSORPTION
• Calcitriol (D3)
• PTH
• Acidity (Low PH)
• Protein rich diet
• Growth Hormone
• Pregnancy, Lactation
• Milk sugar (Lactose)
• Oxalates & phytates – form Ca salts
• High dietary fibers
• Excess Phosphates & Magnesium
• Diet rich in fats – Ca soaps
• Chronic renal failure
• Glucocorticoids

23. REGULATION OF
PLASMA CALCIUM
LEVELS
1. In case of hypocalcemia:
• Activates 25-hydroxy-
cholecaliferol 1-hydroxylase.
• Mobilization of Ca and P
.
• Renal tubular reabsorption.

24. 2. In case of
hypercalcemia:
• Thyroid Para-
follicular cells (C -
cells)

25. REGULATION OF PLASMA PHOSPHATE LEVEL

26. APPLIED ASPECT

27. OSTEOPOROSIS
• WHO defines osteoporosis as a bone density
that falls 2.5 standard deviations (SD) below
the mean for young healthy adults of the
same sex— also referred to as a T-score of –
2.5.
• Male to female ratio 1:4.
• More common in post menopausal women.

28. ETIOLOGY:

29. 1. Fracture after minor trauma may
be first indication.
2. Stiffness, Weakness.
3. Back pain: Episodic, acute , low
thoracic/high lumbar pain.
4. Decrease in height
5. Kyphosis
6. Dowager’s hump
7. Early satiety
CLINICAL
MANIFESTATIONS:
Dervis E. Oral implications of osteoporosis. Oral surgery, oral medicine, oral pathology,
oral radiology, and endodontology. 2005 Sep 1;100(3):349-56.
ORAL MANIFESTATIONS:

30. TREATMENT:
1. Physical therapy program of gentle exercise and activity.
2. Lifestyle modification.
3. Drug therapy to slow disease progress
4. Supportive devices
5. Surgery

31. RICKETS
• Characterized by bone deformities due to
incomplete or under-mineralization of bones.
• In rickets, the plasma level of calcitriol is
decreased and alkaline phosphatase activity is
elevated.
 Rickets during the time of tooth formation is
the most common cause of enamel hypoplasia.
 Shelling & Anderson - in rachitic children: 43%
of teeth showed hypoplasia.

32. ORAL MANIFESTATIONS:
• Enamel hypoplasia of primary
teeth.
• Tooth loss at a young age.
• Recurrent abscesses.
• Delayed eruption and
development.

33. OSTEOMALACIA
 Demineralization of
preformed bones.
 Women with multiple
pregnancies, lactating
mothers.
 Minimal exposure to sunlight.
 Increased alkaline
phosphatase & PTH.
Clinical features:
• Bone pain and tenderness
• Peculiar waddling or
“penguin”gait
• Tetany
• Greenstick bone fractures
• Myopathy

34. Oral manifestation:
• Delayed enamel & dentin
formation
• Thin or absent trabeculae
• Loosened teeth
• Weakened jaw bones

35. RENAL RICKETS
 Chronic renal failure
 Calcidiol not converted to calcitriol in kidney.
 Leads to hypocalcemia stimulates PTH bone resorption
 Hypocalcemia & hyperphosphatemia.
 Administration of oral or IV 1, 25-DHCC.

36. HYPERVITAMINOSIS D
 Early symptoms include nausea, vomiting, anorexia, thirst,
diarrhoea, stupor.
 Marked increase in plasma calcium level.
 Causes calcification of soft tissues & organs.
 Renal stones of calcium oxalate & renal failure.
 Generalised osteoporosis.

37. HYPOCALCEMIA TETANY
• Plasma Ca2+ <7.5 mg/100ml.
• For each gram decrease of albumin from
normal (i.e., 4.0 mg/100ml), [Ca2+] decreases
by 0.8 mg/100ml.

38. CAUSES OF HYPOCALCEMIA
• Hypoparathyroidism
• Vitamin D deficiency
• Chronic liver disease and renal
failure
• Medullary carcinoma of thyroid
• Rickets, osteomalacia,
osteoporosis

39. CLINICAL FEATURES: ORAL MANIFESTATIONS:
1. Delayed eruption
2. Root dilacerations
3. Microdontia
4. Dental caries

40. Calcium gluconate contains 90 mg of elemental calcium per
10 mL ampule, and usually 1 to 2 ampules (180 mg of
elemental calcium) diluted in 50 to 100 mL of 5% dextrose
is infused over 10 minutes.
Oral calcium and vitamin D or an activated vitamin D
metabolite such as calcitriol
TREATMENT:

41.  <2mg/100ml in rickets.
 Def. of enzyme alkaline phosphatase.
 C/F:
Infantile form Severe
rickets Bone
abnormalities Failure
to thrive
Childhood
Loss of primary teeth
Increased infection Growth
retardation Rachitic like
deformation, lung., renal, GI
disorders
Adult
Spontaneous fracture
HYPOPHOSPHATASIA:

42.  Oral manifestations:
Premature loss of primary teeth
Gingivitis
 Radiographic features:
Hypocalcification
Large pulp chambers
Alveolar bone loss

43. HYPERCALCEMIA
• serum Ca2+ >12 mg/100ml in an individual with
normal serum albumin concentration.
CAUSES : Increased absorption
Vitamin D excess
Elevated PTH
Increased bone resorption
Decreased urinary excretion
Paget’s disease and multiple myeloma

44. CLINICAL FEATURES:

45. MANAGEMENT OF HYPERCALCEMIA

46. HYPERPHOSPHATEMIA
• serum phosphorous is >4.5mg/100ml.
• Increased serum P & decreased PTH
CAUSES:
Hypoparathyroidism
Renal failure
Diabetes mellitus
Acromegaly
EFFECTS OF HYPERPHOSPHATAEMIA
1. Rhabdomyolysis
2. Cardiamyopathy
3. Respiratory insufficiency
4. Erythrocyte dysfunction
5. Nervous dysfunction
6. Skeletal dysfunction
7. Metabolic acidosis.

47. PERIODONTAL DISEASE DUE TO DIETARY CALCIUM
DEFICIENCY AND/ OR DIETARY PHOSPHOROUS
 Henrickson suggested:
High incidence of periodontal disease in natives of India-attributed in part
to their low dietary calcium & phosphate intake.
 Labile for Resorption- Alveolar bone
Vertebrae
Ribs
Long bones
Nutrition and Immunology: Principles and Practice edited by M. Eric Gershwin, J. Bruce German, Carl L. Keen

48. • Vitamines are organic components while minerals are inorganic
components that are required in our diet for growth and maintenance of
good health.
• Vitamin D regulates the plasma calcium and plasma phosphate levels.
• These elements are interconnected with each other, hence, deficiency of
any one would lead to imbalance in body.
• Vitamin D is considered a calciotropic hormone while cholecalciferol is a
prohormone.
CONCLUSION

49. • Calcium & phosphate are key elements required in the metabolism
of bone and bone health.
• Deficiency would lead to osteoporosis, rickets, osteomalacia.
• People with lower vitamin D levels had more attachment loss.
• Pregnant women with PD had lower vitamin D levels and were twice
as likely to have vitamin D insufficiency

50. REFERENCES
1. Guyton’s Textbook of Medical Physiology; 8th edition.
2. Biochemistry by Dr. U Satyanarayana 3rd edition.
3. Textbook of biochemistry with biochemical significance by Prem Prakash
Gupta.
4. Ferguson, John H. (1936). THE BLOOD CALCIUM AND THE CALCIUM
FACTOR IN BLOOD COAGULATION. Physiological Reviews, 16(4), 640–
670.
5. Bolat M, Chiriac MI, Trandafir L, Ciubara A, Diaconescu S. Oral
manifestations of nuritional diseases in children. Romanian Journal of Oral
Rehabilitation. 2016 Apr 1;8(2):56-60.
6. Mizumoto T. Effects of the calcium ion on the wound healing process.
[Hokkaido igaku zasshi] The Hokkaido journal of medical science. 1987
Mar;62(2):332.