dr.sarma@works 1 the explosion of knowledge. 2 neurotropic agents - a review dr.r.v.s.n.sarma, m.d.,...
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Dr.Sarma@works 1
The Explosion of Knowledge
2
Neurotropic Agents - A Review
Dr.R.V.S.N.Sarma, M.D., M.Sc., (Canada),Consultant Physician,
Tiruvallur 602 001.
Dr.Sarma@works 3
Neutropic Vitamins Reviewed
Methycobalamin (CH3 B12) Folic Acid (FA) Pyridoxine (Vitamin B6) Alpha Lipoic Acid (ALA) Gamma Linoliac Acid (GLA) Acetyl L-Carnitine (ALC) Gabapentine (GBP) Coenzyme Q 10 (Ubiquinone) NAC (N-acetyl cysteine)
Dr.Sarma@works 4
Neutropic Vitamins Reviewed
Methycobalamin (CH3 B12) Folic Acid (FA) Pyridoxine (Vitamin B6) Alpha Lipoic Acid (ALA) Gamma Linoliac Acid (GLA) Acetyl L-Carnitine (ALC) Gabapentine (GBP) Coenzyme Q 10 (Ubiquinone) NAC (N-acetyl cysteine)
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The Question
Are YOU using Methylcobalamin ? Based on what sort of evidence?
Standard Medical Text Good Review Article on it Unbiased CME “Experts” use it and endorse it The Pharma companies push it Try something because nothing works
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The Question 2
Methylcobalamin - is it a better B12 ? What is the quality of evidence ? In what conditions is it useful ? What is the dosage, route and how long ? Biochemical basis for its use Other agents which are co prescribed
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The Quality of Evidence
RCT- Class I Evidence Single blind, Double blind Placebo controlled, Comparative Multi-centric, Trans-national Large number of patient populations Objective assessment criteria Statistical evidence P value, RR, AR Best in rating - Hypothesis provingEg. Atorvastatin, Ramipril, PTCA
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The Quality of Evidence
Cohort studies- Class II Evidence Two or more self selected groups Prospectively followed for years Outcomes studied Conclusions drawn Good if properly designed Hypothesis testingCrash helmets, Seat belts in cars etc.,
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The Quality of Evidence
Case-control -Class III Evidence Cases of the disease in good number Matched controls Exposure of interest analyzed Retrospective – Problems Weaker in evidence Hypothesis generatingHiroshima Nagasaki, Bhopal gas tragedy
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The Quality of Evidence
Cross sectional -Class IV Evidence One time examination of the group No follow up – to future time No retrospective – into past events Weakest in evidence – At best prevalence estimatesPrevalence of obesity and Diabetes or CHD
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The Quality of Evidence
Case reports – No evidence status Isolated case studies by physicians Dissertations, Thesis reports, News letter reports Out break reports Lay press reports At best thought provoking
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The Quality of Evidence
Anecdotal quotes – No evidence status Vague claims that something works Secretive formulae – eg. asthma cures “My experience” tells me – things At best some respect to the expert
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The Quality of Evidence
International Guidelines – JNC, ADA Recommendations by professional bodies like WHO,
AHA “Reputed Journal” publications- Lancet, JAMA, NEJM,
Post graduate Medicine J FDA like approvals for use - indications Pharmaceutical company trials
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Bias versus Skepticism
Bias – constant belief that something works even though there is no class I or II evidence
Skepticism – brushing away something as useless without proper knowledge on it or in spite of good evidence that it may work.
Both are dangerous
Biochemical or patho-physiological basis may not always be established to start with – eg. Penicillin
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CAN WE TREAT NEUROPATHY AT ALL ?WILL THE NEURONS REGENERATE ?
A SPOT LIGHT ON METHYLCOBALAMINE
A special form of “New B12” may help
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CAN WE TREAT NEUROPATHY AT ALL ?DOES THE NEURON REGENERATE ?
A SPOT LIGHT ON METHYLCOBALAMINE
Research has lookedat Methylcobalamin for many disorders
Albeit, in a weaker way !!
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You may be veryinterested in how
it could help
CAN WE TREAT NEUROPATHY AT ALL ?DOES THE NEURON REGENERATE ?
A SPOT LIGHT ON METHYLCOBALAMINE
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A Rose is Rose is a Rose
But all B12
are not B12
are not B12
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The Vitamin B12 Family
Cyanocobalamin – CN-B12
Hydroxycobalamin – OH-B12
5’-Adenosylcobalamin- AS-B12
Methylcobalamin- CH3-B12
Inactive Active
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Vitamin B12
By far the most complex vitamin in structure Made up of a planar corrin ring (4 pyrroles) – similar to Hb;
the cobalt is attached to 4 pyrroles The only vitamin that possesses a metal ion (cobalt) as
part of its structure The major cofactor form of B12 is AS-cobalamin or 5’-
deoxy AS-cobalamin Small amounts of Methylcobalamin also occur Red in colour, Heat and light sensitive Body stores 5 mg - 2-3 μgs /day - sufficient for 5 years MC is the most abundant B12 in breast milk
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Vitamin B12
Synthesized by bacteria and stored in animal body Commercially available as CN B12, OH B12, CH3 B12 Stored in the liver as the Transcobalamin I Absorbed only in the presence of the intrinsic factor (a
glycoprotein released by parietal cells) Transported to tissues via transcobalamin II Transcobalamin I is the storage form Present in foods such as liver, fish, eggs, milk Absent in vegetables and fruits None in Vegan Vegetarian diet
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Vitamin B12
Biochemical Reactions
Coenzyme in DNA and Serotonin synthessis Synthesis of Purines, Pyrimidines, NA Synthesis of RBC and Proteins Maintains Myeline sheath of Nerve cells 3 Carbon Fatty Acid Metabolism Methylation Reactioms
Homocysteine to Methionine Methyl melonyl CoA to Succinyl CoA Tetrahydrofolate to Methyl Tetrahydro Folate SAM-e (S-Adenosyl Methionine) –powerful mood elevator
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The Vitamin B12 Family
The Grand Parent is the CN B12
Absorbed from gut - R factor + IF - Ileum Transported as Transcobalamin II Stored in liver Transcobalamin I –5 mg/ 2 μg
When needed CN is stripped off – GSH OH is added – OH B12 - plasma to cytosol
Adenosylated to AS B12 - Mitochondria
Methylated to CH3 B12 – in cytosol
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This is the Grand Parent
Cyano Cobalamin - CN B12
Meet the Cobalamin Family
Boy friendship with ‘R’ factor
In the stomach
CN B12 + R factor combine with
Intrinsic Factor from the parietal cells of the stomach
CN B12 + IF - Complex - Marry
Enter intestinal cells of Ileum
CN B12 + IF Complex Divorce
IF is released and recycled
CN B12 combines with Trans
cobalamin II and gets into Plasma Transcobalamin II, the Vehicle
CN B12 + Transcobalamin I
stored in the liver and the TC II is released and recycled
CN B12 is further metabolized
A
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Meet the Cobalamin FamilyCN B12 when needed is
metabolized in the LiverThe Grand Parent
Inactive, a non-coenzyme form
The Parent born Inactive, a non-coenzyme form
Lives in Liver
Cyanide is stripped off from CN B12 - Cobalamin or B12
The Parent is grown up now Inactive, a non-coenzyme form Gets into the
plasma
Hydroxyl group is added to B12 Cobalamin – OH B12
Two Children are born Both Active, Coenzyme
forms Both enter the cell
(Methyl) CH3 is added to OH B12 - CH3 B12
Adenosyl group is added to OH B12 -AS B12
B
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Meet the Cobalamin Family
METHIONINE SYNTHASE Ez
CH3 –H4 FolateH4 Folate
METHYL COBALAMIN COENZYME
Of the Two Active children
First Child is - CH3 B12
SHE lives in the Cytoplasm Very active coenzyme
Homocyst(e)ine (AA)Methionine (EAA)
Purine synthesis
MTHFR Enzyme
C
FOLIC ACID Cousin
OH B12
Purine Pyrimidine
FOLATE TRAP
↑ Homocystenemia
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Meet the Cobalamin Family
METHYLMALONYL- Co A MUTASE ENZYME
ADENOSYL COBALAMIN COENZYME
Of the Two Active children
Second Child is - AS B12
HE lives in the Mitochondria Very active coenzyme
Methylmelonyl CoASuccinyl CoA
Glycolysis cycle
D
Methylmelonic acedemia Methylmelonic aciduria
Amino Acid Metabolism
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Causes of B12 deficiency
Pernicious anemia (autoimmune gastritis against parietal cells - loss of intrinsic factor)
Rarely due dietary deficiency Drugs : OCP, Trimethoprim, Methotrexate,
Phenytoin, Theophyllin Intestinal parasites - D.latum Gastrectomy, Chronic gastritis, PPI, H2 Blocker Old age, Poor dietary Intake, Hypochlorhydria Malabsorption syndromes
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Diagnosis of B12 deficiency
Homocysteine levels (N < 13 μmols/ l) Methyl Malonic Acid (MMA) levels Serum B12 levels (N = 200 - 600 pg/ml) IF Antibodies Schilling test
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Diagnosis of B12 deficiency
Schilling testdistinguishes deficiency caused by pernicious
anemia with that caused by malabsorptioncompares absorption in radiolabeled B12 with
intrinsic factor and radiolabeled B12 without intrinsic factor
in pernicious anemia the B12 with intrinsic factor will be absorbed while the B12 by itself will not
in malabsorption neither will be absorbed
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Manifestation of B12 deficiency
Macrocytic megaloblastic anemia megaloblasts are abnormal erythroid precursors in bone
marrow (most cells die in the bone marrow) reticulocyte index is low hyperchromic macrocytes appear in blood anemia reflects impaired DNA synthesis other cells involved (leukopenia, thrombocytopenia)
Spinal cord degeneration (irreversible) SACD swelling, demyelination, cell death neurological disease results from deficient methylmalonyl-CoA mutase this cannot be treated with folic acid!!
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Treatment of B12 deficiency
Use IM cyanocobalamin or hydroxocobalamin Administer daily for 2 - 3 weeks, then every 2 - 4 weeks for
life Monitor reticulocytosis early to assure treatment is working
(reticulocyte count should go up) Monitor potassium levels to ensure hypokalemia does not
occur due to excessive RBC synthesis
Neurobion-H, Macraberin forte, Vitneurin – B12 1000
Eldervit, Enerject – B12 2500
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Cyano B12 versus Methyl B12
Feature Cyano B12 Methyl B12
IF Required RequiredAbsorption Ileum –Good Ileum - FairTissues Less retained More retainedUrinary Excre. More LessAs Cofactor Inactive ActiveEffect on Ho Cy Good Very GoodHaemopoiesis Effective No effectIn breast milk Low High concentr.
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Routes of AdministrationMethylcobalamin
Oral Transdermal Sublingual Intramuscular Intravenous Subcutaneous Intrathecal (LP)
Subcutaneous route is preferred for a slow release of the Vitamin
IM route is also goodIM inj. is not a must; works orally
Prolonged blood levels after oralS/L bypasses liver metabolism
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients Eating disturbances Cardiac Rhythm Male Impotence Cancer HIV
334 studies referenced on MC in various diseases Almost all the evidence is class III or lower
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients Eating disturbances Cardiac Rhythm Male Impotence Cancer HIV
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Diabetic Neuropathy
Intrathecal Injection of MC in 7 Males and 4 Females – marked improvement
2500 mcg of Mc in 10 ml of saline I.T Repeated every monthly for 4-6 months Improvement in a week; NCV no change Maintained up to 4 years; No side effects ALA + MC 5 mg orally daily for DM PN 500 mcg t.i.d for 4 months orally on 50 pts of DM PN were
tried
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients Eating Disturbances Cardiac Rhythm Male Impotence Cancer HIV
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Bell’s palsy
Small no of subjects studied Oral as well as IM MC tried One group oral steroids + Electrical stimumulation The other group, the above 2 + MC In MC group, the recovery was faster Needs large scale RCT Ultra high doses (500 mcg per kg body wt) = 30 mg per
day may help in nerve regeneration
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients Eating Disturbances Cardiac Rhythm Male Impotence Cancer HIV
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Alzheimer's AD
Pre senile dementia Becoming very common Due oxidative stress and ROS MC in 3 to 4000 mg per day is tried and found to produce
some improvement IV MC used on 10 patients – found useful In Autism found to be very useful Only IM MC tried on 85 children – 60% showed
improvement – speech better
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients Eating Disturbances Cardiac Rhythm Male Impotence Cancer HIV
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Parkinson’s Disease PD
Small number of patients tried IM MC was used Improvement in tremor and rigidity Motor function less improved Needs large scale RCTs
Allergic Disorders1. IgE, Histamin and IL-2, IL-4 are reduced –2. This causes reduction in allergic reactions
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients Eating Disturbances Cardiac Rhythm Male Impotence Cancer HIV
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MS – ALS – MND
In Multiple Sclerosis visual and auditory improvement No improvement in motor function Massive dose of 60 mg/day for 6 months tried Combination of high doses of MC, FA, B6 Ultra high doses like 40 mg daily S/L for MS, ALS or MND
or Toxic PN
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients Eating Disturbances Cardiac Rhythm Male Impotence Cancer HIV
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Stroke
Isolated anecdotal experiences No specific trials Instead of conventional B12, MC was given Transmethylation reactions in the hippocampal region of
the brain may be involved in the functional improvement after MC in Ischemic stroke
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients Eating Disturbances Cardiac Rhythm Male Impotence Cancer HIV
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Hearing Loss, ↓Visual Acuity
Retinal glucotoxicity in DM is reduced Improved vision Senile sensori-neural deafness – some improvement Improves Oto-toxicity due to Gentamycin
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients Eating Disturbances Cardiac Rhythm Male Impotence Cancer HIV
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Memory Disturbances CFIDS
Several mgs/day of MC are required Cognitive function impairment disorders showed
improvement Muscular dystrophies also benefited Glutamate is the NT in brain Glutamate excess – Neuronal degeneration – MC corrects the Glutamate toxicity PSP (post synaptic potentials) amplitude is modulated
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients Eating Disturbances Cardiac Rhythm Male Impotence Cancer HIV
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Hyper Homocysteinemia
A proved risk factor for CHD and stroke Dramatic drop in HC levels From 175 μmols/L to < 6 μmols/L Oral MC better than IM MC - found to have prolonged
effect IV MC works faster for severe ↑ HC FA + MC is the best treatment Oral doses of minimum 2000 mcg/day for 4 months
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients Eating Disturbances Cardiac Rhythm Male Impotence Cancer HIV
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Sleep Disturbances
Melatonin synthesis from pineal gland Methylcobalamin releases Melatonin early and drops its
levels early MC amplifies Melatonin synthesis Sleep quality, day time concentration improved 3000 mcg daily for 4 weeks 1500 to 6000 mcg are tried safe and non toxic Skin rashes and diarrhea are occassional
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients Eating Disturbances Cardiac Rhythm Male Impotence Cancer HIV
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Haemodialysis (HD) Patients
OH B12 passes the dialysing membrane Uremic and diabetic neuropathy on MHD 9 patients on 500 mcg IV thrice a week for 6 months –
some improvement HD patients have high levels of HC Rx with MC + FA was found to be beneficial
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients GI Effects Cardiac Rhythm Male Impotence Cancer HIV
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GI Effects
Protects against toxins Protects from Hg toxicity Acrylamide toxicity Botulinum toxoid and toxins Helps with SH transfer – detoxification by liver –
37 pts of Viral Hepatitis studied Along with L-carnitine improves appetite
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients Eating Disturbances Cardiac Rhythm Male Impotence Cancer HIV
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Heart rate variabilty
MC’s effect on heart rate variability Effect on the Sympathetic / parasympathetic tone
balance MC found to have better effect than
cyanocobalamine
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients Eating Disturbances Cardiac Rhythm Male Impotence Cancer HIV
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Male Impotence
6 mg per day orally for 16 weeks Sperm count improved 37% Motility improved by 50%
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients Eating Disturbances Cardiac Rhythm Male Impotence Cancer HIV
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Cancer and Immune Function
No effect on tumour cell proliferation T cell function improved T Helper function improved Animal studies or small human studies
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The Literature and Methylcobalamin
Diabetic Neuropathy Bell’s Palsy Alzheimer's AD Parkinson's Disease PD ALS – MND Stroke Hearing Loss, Eye Memory disturbances
Homocysteine excess Sleep Disturbances HD patients Eating Disturbances Cardiac Rhythm Male Impotence Cancer HIV
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HIV
Inhibits infected Monocytes and Lymphocytes May be intestinal defective absorption T helper cells increased CD 4 counts decreased Dementia in HIV – some improvement PN in HIV is due to the Rx drugs Hypothesis – Hyper methylation may suppress the viral
replication – Is it peculiar to HIV virus ? Are other virus amenable ?
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Dosage
Minimum of 1500 mcg to 6000 mcg/ day oral / IM To be used for prolonged periods 3 to 6 months Even larger doses are tried in refractory cases Combination with ALA in PN Combination with FA in ↑ HC Cocktail of FA + MC + B6
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Neutropic Vitamins Reviewed
Methycobalamin (CH3 B12) Folic Acid (FA) Pyridoxine (Vitamin B6) Alpha Lipoic Acid (ALA) Gamma Linoliac Acid (GLA) Acetyl L-Carnitine (ALC) Gabapentine (GBP) Coenzyme Q 10 (Ubiquinone) NAC (N-acetyl cysteine)
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N
N N
NN
H
CN
CH
H
OH
H2N
O COOH
COOH
FOLIC ACID
Also known as folacin, vitamin M, Widely available in plant foliage
pteroic acid + glutamic acid = pterylglutamic acid
Folic acid
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Folic Acid
Coenzyme for RBC and DNA synthesis Folates are donors of 1-C units (Methyl) Tetra Hydo Folate THF is the active form Two reductions by DHF reductase Folic acid deficiency in birth defects Supplimentation of FA reduces HC levels
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Folic Acid - Biochemistry
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Folic Acid
Absorbed by both active and passive transport On the average we absorb 50 -200 μg per day
(about 10 -25% of dietary intake) Stored as 5-methyl THF (5 -20 mg) Found in green vegetable, dietary yeasts, liver,
kidney Bacteria synthesize their own folic acid
(dihydropteroate synthetase)
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Folic acid
Biochemical functions One carbon fragment transfer (formyl, methyl,
hydroxymethyl)Conversion of HC to methionineConversion of serine to glycineSynthesis of thymidylic acidSynthesis of purines (de novo)Histdine metabolismSynthesis of glycine
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BIOCHEMICAL ACTIVATION OF FOLIC ACID
FOLIC ACID 7,8-DIHYDROFOLIC ACID (DHFA)
TETRAHYDROFOLIC ACID (THFA)N5, N10-METHYLENETETRAHYDROFOLIC ACID
N5-FORMYL TETRAHYDROFOLIC ACID (LEUCOVORIN, FOLINICACID, CITROVORUM FACTOR)
OTHER FORMS OF THFA: N 5-METHYL THFA N 5-FORMIMIDO THFA
N10-FORMYL THFAN5, N10-METHENYL THFA
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Deficiency of folic acid
Inadequate intake Defective absorption (most common)
spruegastric resection and intestinal disordersacute and chronic alcoholismdrugs (anticonvulsants and OCP)pregnancypellagra
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Deficiency of folic acid
Abnormal metabolism of folates folic acid antagonists (dihydrofolate reductase
inhibibitors - methotrexate, pyrimethamine, trimethoprim)
enzyme deficiency vitamin B12 deficiency oral contraceptives
Increased requirement pregnancy, infancy
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Neutropic Vitamins Reviewed
Methycobalamin (CH3 B12) Folic Acid (FA) Pyridoxine (Vitamin B6) Alpha Lipoic Acid (ALA) Gamma Linoliac Acid (GLA) Acetyl L-Carnitine (ALC) Gabapentine (GBP) Coenzyme Q 10 (Ubiquinone) NAC (N-acetyl cysteine)
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Pyridoxine (vitamin B6)
N
CH2OH
CH2OHHO
H3C
PYRIDOXINE
A pyridine derivative
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Pyridoxine
Involved in > 100 enzyme reaction In CHO, Fat and Protein metabolismCatalyzes all AA reactions –Without this all AAs are EAAs In Hb and neurotransmitter synthesis Its family has got three members
Pyridoxal, Pyridoxine, Pyridoxamine
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Pyridoxine
Vitamin B6, anti-dermatitis factorWidespread occurrence
pyridoxine: mostly in vegetable productspyridoxal and pyridoxamine: mostly in animal
productsPyridoxine is stable in acid solution, but
unstable in neutral or alkaline solutions
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Pyridoxal phosphate
Biochemical functions:• Decarboxylation of amino acids• Transaminase reactions• Racemization reactions• Aldol cleavage reactions• Transulfuration reactions• Conversion of tryptophan to niacin• Conversion of linoleic acid into arachidonic acid • Formation of sphingolipids
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Pyridoxine
Deficiency: Difficult to produce in humans May be accomplished artificially with a pyridoxine
antagonist (deoxypyridoxine) Symptoms include: nausea and vomiting, seborrheic
dermatitis, depression and confusion, mucous membrane lesions, peripheral neuritis, anemia
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Pyridoxine deficiency
Can be monitored by measuring the level of xanthurenic acid in the urine
This is related to a decrease in kynureninase activity (pyridoxal phosphate is the coenzyme)
Kynurenine, a breakdown product of tryptophan is normally converted to kynurenic acid – but in B6 deficiency it is shunted to form xanthurenic acid
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Pyridoxine
Requirements children: 0.5 – 1.2 mg adults: 2.0 mg pregnancy: 2.5 mg
requirement for B6 is proportional to the level of protein consumption
Therapeutic uses deficiency to counteract the effects of antagonists certain rare forms of anemia in women taking oral contraceptives (estrogen shifts
tryptophan metabolism)
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Neutropic Vitamins Reviewed
Methycobalamin (CH3 B12) Folic Acid (FA) Pyridoxine (Vitamin B6) Alpha Lipoic Acid (ALA) Gamma Linoliac Acid (GLA) Acetyl L-Carnitine (ALC) Gabapentine (GBP) Coenzyme Q 10 (Ubiquinone) NAC (N-acetyl cysteine)
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Structure of ALA
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Alpha Lipoic Acid (ALA)
8 C- Sulfur containing compound Involved in metabolism as anti-oxidant It has ring on a chain like Biotin Lysine is the protein moiety, acyl carrier Universal Antioxidant Component of pyruvate and alpha ketoglutarate
dehydrogenases – KrebsALA 100, Lipocid 100mg cap – 300 mg/day BF
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Alpha Lipoic Acid (ALA)
ALA neutralizes OH free radicals, Hypochlorous acid, singlet O2 radicals
Chelates Iron, Copper and transit metals It is absorbed – converted to Di Hydro LA DH LA is also antioxidant ALA is both fat and water soluble Active in membranes and aqueous milieu Protects against CVD
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Redox reactions of ALA
ALA to DH-LA
NAD NADH+ H+
DH-LA to ALADH Vit C
GSH - DSGSH Vit C
Vit E
ROO-
ROOH
Vit E +
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Neutropic Vitamins Reviewed
Methycobalamin (CH3 B12) Folic Acid (FA) Pyridoxine (Vitamin B6) Alpha Lipoic Acid (ALA) Gamma Linoliac Acid (GLA) Acetyl L-Carnitine (ALC) Gabapentine (GBP) Coenzyme Q 10 (Ubiquinone) NAC (N-acetyl cysteine)
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Gamma Linoliec Acid (GLA)
Useful in meylin synthesis Diabetic Neropathy it is useful Reduces the paresthaesias, burning Available as GLA 120 One cap b.i.d to t.i.d for several weeks
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Neutropic Vitamins Reviewed
Methycobalamin (CH3 B12) Folic Acid (FA) Pyridoxine (Vitamin B6) Alpha Lipoic Acid (ALA) Gamma Linoliac Acid (GLA) Acetyl L-Carnitine (ALC) Gabapentine (GBP) Coenzyme Q 10 (Ubiquinone) NAC (N-acetyl cysteine)
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Acetyl L -Carnitine (ALC)
Anti oxidant property similar to tocopherol L isomer only active -D Carnitine inhibits. Available as 500 mg cap. Carnivit, Carnitor Dosage 1 to 2 grams daily In primary carnitine deficiency – myopathy Patients on HD may have deficiency Cardiomyopathy and Ischemic heart disease
L- Carnitine is found to improve myocardial function and reduce oxygen demand.
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Neutropic Vitamins Reviewed
Methycobalamin (CH3 B12) Folic Acid (FA) Pyridoxine (Vitamin B6) Alpha Lipoic Acid (ALA) Gamma Linoliac Acid (GLA) Acetyl L-Carnitine (ALC) Gabapentine (GBP) Coenzyme Q 10 (Ubiquinone) NAC (N-acetyl cysteine)
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Gabapentine (GBP)
Available as 300 and 400 mg caplets Gabantine (Sun), Gabalept (Micro) 300 to 400 mg b.i.d for 3 months In Diabetic neuropathy, Post HZ neuralgia Class II evidence of efficacy Costs Rs. 9/- for 300 mg caplet
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Neutropic Vitamins Reviewed
Methycobalamin (CH3 B12) Folic Acid (FA) Pyridoxine (Vitamin B6) Alpha Lipoic Acid (ALA) Gamma Linoliac Acid (GLA) Acetyl L-Carnitine (ALC) Gabapentine (GBP) Coenzyme Q 10 (Ubiquinone) NAC (N-acetyl cysteine)
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Coenzyme Q10, NAC
Coenzyme Q 10 (Ubiquinone) NAC (N-acetyl cysteine) Tried in CHF, HT, PD, Anti aging Both are claimed to help on Redox reactions To help the antioxidant mechanism Recycle the scavenger antioxidants Very soft evidence – not to be tried
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Pros for Methylcobalamin
Sound biochemical basis that it works Active coenzyme form - CH3 B12
Many publications – lot of noise, there must be some real effect
In ↑Homcyseine and sleep disorders, there is some what hard evidence
In chronic neurological conditions, there is nothing much to offer – why not try this?
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Cons for Methylcobalamin
No RCTs of repute comparing Cyano, Methyl, Hydroxy B12 and placebo
No prophylactic effect studied Subjective improvements – not objective Very large doses for long periods needed No effect on haemopoiesis demonstrated 80% of cobalamin functions are AS B12
Much expensive than cyanocobalamin
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Cons for Methylcobalamin
With adequate FA intake B12 def. is rare Not approved as drug by US FDA etc., Less stable than cyanocobalamin We don’t know why body is converting only small
quantity of B12 to Methylcobalamin May be useful in special groups like HD, AD, PD, ALS,
Autism etc., - rather uncommon No trials with Cyano B12 in such large doses
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Pose these questions
Is the patient a vegan vegetarian ? Is he having B12 diseases ? Is having malabsorption / nutritional deficiency ? Is he having malignancy / immunodeficiency ? Is he on DHFR inhibitors ? Is his Homocysteine level very high ? Is having intractable conditions like AZ, PD, MND,
ALD, MS, Autism, MHD or cerebral dysfunction
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If the answers are ‘Yes’
He requires B12 and Folic acid supplementation Can he managed with Folic acid alone ? Can we not treat with simple B12 +Folic acid If we think of Methylcobalamin give as large a
dose as the patient can afford for as long as possible
Use oral route combining with folic acid Add Alpha Lipoic Acid in neuropathy
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Conclusions
Evidence in favour of Methylcobalamin is rather soft However
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The day we attempt learning new things, we start realizing how inadequate our knowledge is !THAN Q