Vit d is it the mericle vitamine

VIT D IS IT THE MIRCLE VITAMINE

DR : NAGLAA ABO BAKRCOSULTANT CLINICAL PATHOLOGY

What is vitamin?

Vitamin – VITAL AMINE – essential for health“an organic compound, not made at all or in sufficient amounts by the body”

Which is the most important ?

A (or beta carotene)B 1,2,3,4,6,8,10,12

CDEK

Which is the most important ?

A (or beta carotene)B 1,2,3,4,6,8,10,12

CDEK

The literature on Vitamin D has exploded in recent years.

Vitamin D

– Vitamin D2 (ergocalciferol)

• (Pharmaceutical Form derived from Ergol found in Fungus)

– Vitamin D3 (cholecalciferol) • (Natural Form found in food and synthesized in Skin)

• metabolites and analogues of these substances

• Vitamin D

– Precursor (sometimes referred to as a “prohormone”)

– Must be metabolized to become biologically active

• Active form of vitamin D: Calcitriol

Vitamin D

Production, Metabolism, and Biological Function of Vitamin D

1,25(OH)2D3 1,25(OH)2D3

Vitamin D3 25(OH)D3

Prostate

Gland,

Breast,

Colon,

Lung

Calcium

Homeostasis

Muscle Health

Bone Health

Blood pressure regulation

Cardiovascular Health

Immunomodulation (prevention of

autoimmune diseases)

Regulation of

Cell Growth

(cancer prevention)

Liver

Kidney

25(OH)D3=25-hydroxyvitamin D3; 1,25(OH)2D3= 1,25-dihydroxyvitamin D3.Holick MF. Am J Clin Nutr 2004;80(suppl):1678S-88S.

Skin

D D

Milk Orange juice

SupplementCod liver oil

Salmon

Pathophysiology

Vitamin D deficiency leads to impaired intestinal absorption of calcium Which results in decreased levels of calcium levels.

This hypocalcemia gives rise to secondary hyperparathyroidism

It is a homeostatic response aimed at maintaining, initially, serum calcium levels at the expense of the skeleton.

Following this PTH-induced increase in bone turnover, alkaline phosphatase levels are often increased.

http://en.wikipedia.org/wiki/Hypocalcemia

http://en.wikipedia.org/wiki/Secondary_hyperparathyroidism

PTH not only increases bone resorption, but it also leads to decreased urinary calcium excretion while promoting phosphaturia. This results in hypophosphatemia, which exacerbates the mineralization defect in the skeleton.

http://en.wikipedia.org/wiki/Phosphaturia

http://en.wikipedia.org/wiki/Hypophosphatemia

Musculoskeletal Effects

• Maintenance of normal musculoskeletal function

– Skeletal muscle has receptors (VDR) for 1,25(OH)2D3

– Severe vitamin D deficiency is associated with muscle weakness, limb pain & impaired physical function

Vitamin D

Extraskeletal Effects• Regulation of cell growth and effects on immune function

• Epidemiologic studies have shown that living at lower latitudes is associated with a decreased risk of many chronic diseases

• Multiple sclerosis, hypertension, and cancer of the colon, breast, and prostate

• Some studies have shown that increasing vitamin D intake decreases the risk of certain chronic diseases

• Diabetes, rheumatoid arthritis, hypertension, and colon cancer

Action on the intestine

Action on the bone

Action on the kidney

What do we measure ?


• Most assays for 25(OH)D cannot differentiate the two distinct forms , 25(OH) D2 from 25(OH) D3, so the abbreviation 25(OH)D is used.


• The serum 25-hydroxyvitamin D , 25(OH)D level is the best indicator of overall vitamin D status.

because

This measurement reflects total vitamin D from dietary intake and sunlight exposure, as well as the conversion of vitamin D from adipose stores in the liver

Half-life approximately 2 weeks

1,25(OH)2D3 should never be used to determine vitamin D status

Determination of vitamin D status

Half-life :is approximately 4 h.

It circulates at 1000 times lower concentration than 25(OH)D .

The blood level is tightly regulated by serum levels of PTH,calcium, and phosphate.

Serum 1,25(OH)2 D is frequently either normal or even elevated in those with vitamin D deficiency, due to secondary hyperparathyroidism.

Thus, 1,25(OH)2 D measurement does not reflect vitamin D status.

Serum 1,25(OH)2 D does not reflect vitamin D reserves.

People with a granuloma disease such as sarcoidosis can have a high level of serum 1,25-dihydroxy-vitamin D but show a low testing level of serum concentration of 25-hydroxy-vitamin D

because the granulomas, when active, produce serum 1,25-dihydroxy-vitamin D. The body is then protecting itself from a calcium dump ( high calcium level) by having a low 25-hydroxy-vitamin D.

How do we Interpret report

Deficiency :level less than 10 ng/mL .

Insufficient : level between 10 to 30 ng/Ml .

Sufficient ..more than 30 ng/ml .

Frequency of measuring

• Measurement of serum 25-hydroxyvitamin D should follow three to four months of adequate supplementation and should not be repeated if an optimal level(≥ 30 ng/mL) is achieved .

You may need more than the usual dose if taking certain medicines which interfere with

vitamin D.

These include: carbamazepine, phenytoin, primidone, barbiturates and some medicines for the treatment of HIV infection

For example, in patients without clinical improvement after D2 or D3supplementation, lack of increase in the corresponding 25(OH)D2 or 25(OH)D3 and total 25(OH) D levels may indicate inadequate dosing, nonadherence, or malabsorption.

A single dose of 50,000 IU of D2 or D3 produces a similar increase in the total 25(OH)D concentration, but the apparent longer half-life of D3 suggests that less frequent dosing may be needed

.

•Which one of the following biochemical tests provides the best initial assessment of a person's vitamin D status?

•Serum parathyroid hormone (PTH)•Serum 25-hydroxyvitamin D•Serum 1,25-dihydroxyvitamin D•Serum bone alkaline phosphatase•24-hour urine calcium excretion

What does Vitamin D do to make such a difference in

health? Vitamin D ‘affects gene expression”It turns genes on and off.

In the nucleus of all of our cells are chromosomes– one from mum and one from dad.

These are made of DNA – and segments of DNA are genes.

The genes are the blueprint of the cells

•Makes proteins in the cell to • build,• repair, • recover, • fight• function

These only action when needed

For many processes – vitamin D is essential for

the switch to work.

Protein

How the cells make proteins

Messenger RNA makes a copy of the DNA

Goes out of the nucleus to the ‘production’ factory

– the ribosomes

The MRNA runs thru the ribosome like a tape,

giving instructions on the protein to make.

The DNA is the blue print plan

Genes don’t want to be making proteins continuously – they need to be turned on and off – REGULATORS.

Vitamin D is a major regulator in the human.

There are over 230 Vitamin D receptors in the nucleus of most tissues in our bodies.

Proein

Ribosome

The vitamin D receptors (VDR) up or down regulate the activity of the cell production. VDRs have been found by genes

associated with:

•Diabetes•Crohn’s disease•Cancer•Leukaemia•Rheumatoid arthritis•Multiple sclerosis

And we have only just started looking………

This explains why vitamin D may have a role in preventing cancer,

inf luenza, autism, asthma, mult iple sclerosis, and cardiovascular disease, not just curing rickets and

osteomalacia

Vitamin D also tells cells when to divide, stop dividing and also when to die (apoptosis).

With low vitamin D levels, cells may•Not die and become immortal

•Continue to divide out of control

Vitamin D affects cancer cells in a number of ways:

•Switches apoptosis back on – programmed cell death


•Slows down multiplication and spread of cancer cells


•Reduces growth of new blood vessels to feed the cancer and increase spread

Vitamin D also seems to do all the right things for the heart.

• Vit D receptors in the artery walls and heart muscle

• Lowers BLOOD PRESSURE via the ACE system

• Improves insulin sensitivity• Reduces inflammation• Improves vessel wall recovery to injury

There are many diseases where low Vitamin D levels are found:

Parkinson’s disease – reduced production of dopamine in the substantia nigra.

Archives of Neurology, March 2011 American Heart Association's (AHA) Annual Scientific Sessions,

Chicago, IL November 15, 2010

http://archneur.ama-assn.org/cgi/content/short/68/3/314

Low Vitamin D doubles the risk of having a stroke


Chicago, IL November 15, 2010 Journal of Allergy and Clinical Immunology June 8, 2010

Diabetes Care. 2011 Ma


http://www.ncbi.nlm.nih.gov/pubmed/20538327

Children with low Vitamin D levels doubled the risk of admission to hospital





http://www.ncbi.nlm.nih.gov/pubmed/20538327

Risk of diabetes rises – 57%




Macular Degeneration – 59%




Depression is 11 TIMES as common in those with low vitamin D levels




Serotonin, the brain hormone associated with mood elevation, rises with exposure to bright light and falls with decreased sun exposure.

One study found low serum vitamin D concentrations in patients with schizophrenia.

Vitamin D acts as a catalyst in glutathione production.

Low glutathione levels have been implicated in several mental health disorders.

•Whenever there is a risk of infection, make sure your Vitamin D levels are optimal.

•Is it a coincidence that flu and infections are higher in the low sun winter months?

Vitamin D switches on the production of over 200 antimicrobial peptides – the most important one we know of is CATHELICIDIN – a naturally occurring broad-spectrum antibiotic.

Vitamin D is essential for our immune system

The T cells have vitamin D receptors on their surface, allowing them to transform into KILLER cells and also to multiply

“Without vitamin D the white cells lie dormant!”

An army of specific killer cells attacks and kills the invader

Once the diseases have developed, Vitamin D levels still make a difference:

•High vit D Doubles the survival in people with colon cancer •High vit D Reduces heart failure hospitalisation and mortality

•Women taking vitamin D lowered heart deaths by 33%

•Women given Vitamin D supplements reduced cancer by up to 60%

British Journal of Cancer September 15, 2009; 101(6):916-23 European Society of Cardiology (ESC) Congress 2010 August

28-September 1, 2010, Stockholm, Sweden 2nd annual conference on Cardiovascular Disease and

Epidemiology Prevention in Honolulu, Hawaii. April 23, 2002

These results are almost too good to be true – BUT ARE THEY TRUE.

Fracture and Vitamin D Deficiency Case Study 1

• 26 year old male of Middle Eastern heritage with 2 1/2 years of service, lived in Northern U.S. last 9 years.

• Sustained stress fracture of left tibia during training (AIT). – X-rays reveal stress fracture at 4 weeks. Placed in cast for 12

weeks. Cast removed and given tramadol for chronic pain.

• Deployment to Iraq– Exposed to 5 blasts, 2 with brief loss of consciousness– Changed to Percocet for pain, later evacuated for acute

psychosis

• Psychosis resolved and bone scan revealed non-union of stress fracture at 17 months.

• Patient referred to Deployment Health Clinical Center – PTSD, anxiety, and co-morbid chronic left tibial pain.

• Screening 17 months after fracture: vitamin D level of 11 ng/ml (normal > 30).

Case Study 2

• 36 year old African American with 6 years of service, signed up after 9/11 while living in the northern U.S.

• Deployment to Iraq– 3rd month: rolled off cot during mortar attack and injured right

wrist. Negative X-rays. Conservative measures for chronic pain.– 4th month: re-injured right wrist when 84 pound machine gun was

dropped on it.– 9th month: chronic pain leads to medical evacuation.

• Arthroscopy performed with some improvement in pain, Conservative management continued.

• Nuclear scan for chronic pain 7 months after injury: – stress changes in lunate wrist bone and posttraumatic changes

in triquetrum. Conservative management remains indicated.• Patient referred to Deployment Health Clinical Center for co-morbid

PTSD, anxiety, and chronic right wrist pain.

• Screening 14 months after injury: vitamin D level of 12 ng/ml (normal > 30).

Deployment Health Clinical Center

• Of 94 referrals seen from March 2005 until September 2006, 83 (88%) were screened.

– > 90% with chronic musculoskeletal pain

– Either multiple unexplained physical symptoms . 14 with fibromyalgia.

• 46% (n= 38) have low Vitamin D (< 30 ng/ml)– Average for those deficient: 13 ng/ml (range: 6-19)

• Pathophysiology for the association of chronic pain and Vitamin D Deficiency is not known

• However, Vitamin D receptors have been recognized in the CNS, as well in many other tissues, suggesting vitamin D has essential functions as a hormone outside of bone metabolism

• Chronic pain has been associated with CNS dysfunction

• Vitamin D receptor knock-out mice demonstrate anxiety behaviors

The Planet is Vitamin D Deficient

Thank You

All That Glitters is not GOLD…

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Vit d is it the mericle vitamine