Recurrent aphthous stomatitis (RAS) is one of the most common oral mucosa lesions

seen in primary care. The most treatments given to patients suffering from RAS achieve

“short term” therapeutic goals, such as alleviation of pain, reduction of ulcer duration, and

recovery of normal oral function. Just a few reported treatments have achieved “long term”

therapeutic goals, such as reduction of the frequency and severity of RAS and maintenance of

remission Although the precise role of vitamin B12 deficiency in the pathogenesis of RAS is

unclear, suppression of cell-mediated immunity and changes in the cells of the tongue and

buccal mucosa have been reported [51,52]. We have reported previously the successful

treatment of three RAS patients with intramuscular vitamin B12 injections [53]. According to

our own clinical experience of 5 years, treatment with vitamin B12 achieves “long term”

therapeutic goals and can be effective for patients suffering from RAS, regardless of their

serum vitamin B12 level. We have begun randomized, double placebo controlled clinical

trials, which should confirm this observation.

POTENTIAL ROLE AND USES OF VITAMIN

B12 IN PREVIOUSLY UNCOMMON AREAS

A possible correlation between vitamin B12 and problems of fertility, which indicates

vitamin B12 deficiency as one of causes of recurrent abortions and the use of vitamin B12 in

initial treatments in order to prevent these conditions, has been under debate for long time

[54,55,56]. In a statistical metaanalysis performed on five studies in which serum B12 was

The Role and Status of Vitamin B12: Need for Clinical Reevaluation and Change 183

assayed in women suffering from early recurrent abortions (ERA), a significant relationship

was found between ERA and vitamin B12 deficiency [57]. No difference was noticed between

cases and controls for folate. Then vitamin B12 study should be done in ERA women whether

or not hematological or neurological abnormalities are present.

Osteoporosis is a widespread problem, which frequently has devastating health

consequences because of its association with fragility fractures. The total number of fractures,

and hence the cost to society, will increase dramatically over the next 50 years as a result of

demographic changes in the number of elderly people. Thus, prevention of osteoporosis by

identifying risk factors or risk indicators, as well as the development of new treatment

strategies, is a major health issue. Recent data suggest that vitamin B12 affects bone

metabolism, bone quality and fracture risk in humans [58]. Strokes increase the risk of

subsequent hip fracture by 2 to 4 times. Hyperhomocysteinemia is a risk factor for both

ischemic stroke and osteoporotic fractures in elderly men and women. In a population with a

high baseline fracture risk, combined treatment with folate and vitamin B12 has been shown

to be safe and effective in reducing the risk of a hip fracture in elderly patients following

stroke [59]. The relationship of Hcy and vitamin B12 with bone turnover markers, broadband

ultrasound attenuation (BUA), and fracture incidence in healthy elderly people was studied

by a few researchers, who found that high homocysteine and low vitamin B12 concentrations

were significantly associated with low BUA, high markers of bone turnover, and increased

fracture risk [60]. A preventive vitamin B12 supplementation for healthy people with

mandatory risk factors for osteoporosis and a treatment with vitamin B12 of patients suffering

from osteoporosis could be a promising treatment for this serious problem. Controlled

clinical trials should be conducted to confirm the safety and effectiveness of vitamin B12

therapy for osteoporosis.

Cobalamin carrier proteins,the transcobalamins (TC), are elevated during trauma,

infections and chronic inflammatory conditions. This remains un-explained. It is proposed

that such TC elevations signal a need for cobalamin central to the resolution of inflammation

[61]. Vitamin B12 is an effective scavenger of nitric oxide (NO) [62]. Septic shock has an

extremely high mortality rate, with approximately 200,000 people dying from sepsis annually

in the U.S. The high mortality results in part from severe hypotension secondary to high

serum NO concentrations. Reducing NO levels should be beneficial in sepsis; a possible

approach in reducing NO levels in sepsis is the use an NO scavenger, which would leave

sufficient free NO for normal physiological functions. Animal and human clinical data

suggests that high dose cobalamin may prove a promising approach to systemic inflammatory

response syndrome (SIRS), sepsis, septic and traumatic shock.

Drugs which directly counteract nitric oxide, such as endothelial receptor blockers, NOsynthase inhibitors, and NO-scavengers, not only may be effective in the acute treatment of

migraine, but also are likely to be effective in migraine prophylaxis. The first prospective,

open study indicated that intranasal hydroxocobalamin may have a prophylactic effect in

migraine [63].

A number of studies have demonstrated that cobalamin is important in maintaining

differentiation, proliferation, and metabolic status of cells. NO can cause both apoptosis and

necrosis, making it a good candidate for antitumor therapy. Initially, vitamin B12 was

proposed for use as a scavenger and cytoprotective agent to bind and inactivate NO. The use

184 Ilia Volkov, Inna Rudoy and Yan Press

of vitamin B12 as a carrier to deliver nitric oxide into tumor cells is novel. In one

investigational study was shown that complex NO-cobalamin inhibited tumor growth in vivo

and in vitro by activating the extrinsic apoptotic pathway [64].

STRATEGY FOR PREVENTION AND

TREATMENT OF VITAMIN B12 DEFICIENCY

The question regarding which patients require tests for B12 level continues to be

discussed [65]. It is not always easy to decide whether a patient suffers from vitamin B12

deficiency or not. For initial screening, measurement of serum vitamin B12 levels may suffice.

However, the test for B12 has several pitfalls [66]. Most laboratories set normal limits at 200

to 900 pg/mL, but sensitivity and specificity vary greatly, depending on the method used.

False negatives (ie, elevated levels in the presence of deficiency) can occur in true deficiency,

active liver disease, lymphoma, autoimmune disease, and myeloproliferative disorders. False

positives (i.e., low levels in the absence of deficiency) can occur in folate deficiency,

pregnancy, multiple myeloma, and excessive vitamin C intake. The measurements are quite

accurate for serum vitamin B12 levels below 100 pg/mL, but they discriminate poorly when

vitamin B12 levels are between 100 and 400 pg/mL. When values fall in this range, levels of

serum or urine MMA and homocysteine should be measured. If MMA levels are elevated,

treatment should be initiated. If homocysteine levels are elevated, other causes of the

elevation (e.g., coexisting folate deficiency) should be ruled out. However, serum MMA and

homocysteine tests are expensive, and almost certainly these investigations are not feasible in

most clinics around the world.

After the diagnosis of vitamin B12 deficiency has been established, treatment may

commence or additional tests may be done to elucidate the causes of the deficiency. Planning

the strategy for treatment involves decisions concerning dosage, means, and form of vitamin

B12 to be employed, as well as determining need for continuous follow up [67]. Today,

physicians have a choice of several inexpensive treatments that are easy to administer and

have no known side effects. Treatment should be individualized according to patient and

healthcare provider preferences. Different forms of vitamin B12 can be used, including

cyano,- hydroxyl,- and methylcobalamin. Cyanocobalamin is the only form available in the

USA. Hydroxycobalamin may have advantages due to a slower metabolism. The co-enzyme

form, methylcobalamin, is the preferred form in Japan. In most countries vitamin B12 is still

given by intramuscular injection in the form of cyanocobalamin or hydroxycobalamin. As

mentioned, practices concerning both dose and administration vary considerably.

Traditionally, vitamin B12 deficiency has been corrected by parenteral administration of the

vitamin. Intramuscular injections are safe, but may cause local discomfort. Injections are

inconvenient and more expensive due to the need for the patient to visit the doctor in the

clinic or for the provider to see the patient at home. An alternative to parenteral therapy,

lately approved by the FDA, is intranasal administration of cyanocobalamin. In Europe,

intranasal hydroxocobalamin has been widely used for years. The intranasal administration of

500 micrograms of cyanocobalamin weekly attains blood levels that are comparable to those

found with intramuscular injections. A positive clinical experience of many years in several

The Role and Status of Vitamin B12: Need for Clinical Reevaluation and Change 185

countries [68] and current results of some studies [69], which investigated the effectiveness,

safety, and acceptability of oral vitamin B12, suggest that vitamin B12 deficiency may be

treated with oral dose vitamin B12 as effectively as that with injections of vitamin B12. The

evidence derived from limited studies [70] suggests that 2000 mcg doses of oral vitamin B12

daily and 1000 mcg doses initially daily and thereafter weekly and then monthly may be as

effective as intramuscular administration in obtaining short term hematological and

neurological responses in vitamin B12 deficient patients. Oral high dose vitamin B12 is

appropriate for both the replacement therapy in patients with vitamin B12 deficiency and for

maintenance treatment. Most likely oral vitamin B12 can provide an effective alternative to

intramuscular injections. Using different doses of vitamin B12 (from a few micrograms to

dozens of milligrams) is becoming more and more wide spread [30,71]. Because

approximately 1% of orally ingested B12 is absorbed via simple diffusion from the intestine

(independently of intrinsic factor), oral replacement with high doses of vitamin B12 is both

effective and safe, regardless of the etiology of vitamin B12 deficiency. Thus, in pernicious

anemia, vitamin B12 must be given in large amounts (preferably >1,000 micrograms a day).

However, in vegan patients or patients with food-cobalamin malabsorption syndrome and low

gastric acidity, oral B12 may be effective in smaller doses.

We conducted a comprehensive MEDLINE search using combinations of the following

keywords: vitamin B12, vitamin B12 deficiency, treatment with vitamin B12, cobalamin, doses

of cyanocobalamin, hydroxycobalamin, methylcobalamin, We did not find any reference

relating to explanation how a widespread dose regimen of cobalamin for treatment of

different conditions was done. As a result, we concluded that dosage was chose empirically

without solid scientific basis, and today overwhelming majority of practitioners continue to

treat their patients with dosages that were established decades ago, despite new research data

and possibilities provided by modern medicine. For example, cobalamin resistance may occur

in diabetes, renal insufficiency and advanced age, leading to functional cobalamin deficiency,

thus, requiring higher doses. In our opinion, perhaps negative results of some studies or

ineffective treatment of several conditions with vitamin B12 may be explained by insufficient

dose of cobalamin.

NECESSITY OF NEW APPROACH TO

THE PROBLEM OF VITAMIN B12

We know that not only ill individuals with special problems and vegetarians can suffer

from vitamin B12 deficiency, but also patients with low meat intake. There are many articles

indicating the increasing prevalence of low Vitamin B12 level in different segments of general

population [72,73,74,75,76,77]. In the past decade we have also become aware that vitamin

B12 deficiency occurs commonly in industrial countries at different levels of economic and

social status. A high prevalence of symptomatic vitamin B12 deficiency was discovered in a

pre-urban Bedouin area in Southern Israel due to low intake of animal products [72]. Dietary

vitamin B12 deficiency is a severe problem in India, Mexico, Central and South America [73]

and selected areas in Africa [74]. For example, at least 40% of the population in Central and

South America has deficient or marginal plasma vitamin B12 concentrations in almost all

186 Ilia Volkov, Inna Rudoy and Yan Press

areas and in all age groups [75]. As a rule, it appears to be prevalent in 30-40% of those in

the lower socioeconomic levels. Our clinic serves middle to upper-middle class population,

and, according to preliminary data received in our study, frequency of deficient or marginal

vitamin B12 level (<250pg/ml) was about 35%. We cannot extrapolate our finding to general

population in this area, because the study population is a selected sample, but we suppose

that a prevalence of low level of vitamin B12 in the overall population may be similar. Today

there is a tendency in modern society to change habits, for example cessation of smoking,

"fighting" with overweight, accentuating physical exercise, adopting correct eating habits.

We have come to the conclusion that as a result of media information disseminating the

relationship between meat, cholesterol and cardiovascular diseases, consumption of meat,

particularly beef, has decreased. We suppose that the decrease of level of vitamin B12 in the

population with higher educational level is caused by a premeditated decrease in

consumption of animal products. Also in modern society there is a tendency for ideological

motives, particularly among the younger generation, to be vegans. Changes in life style

among segments of the population with high socioeconomic level, on one hand, and the

existence of poverty, on the other, are two main factors in the decreasing consumption of

animal products (particularly red meat). This causes a decrease in the level of vitamin B12 in

general population, and as a consequence, this will increase pathology due to vitamin B12

deficiency (such as neurological and hematological disorders). As mentioned, vitamin B12

deficiency has various and serious health effects. In lieu of these possible developments and

in order to prevent serious health problems, Vitamin B12 routine fortification should be

seriously considered and discussed.

REFERENCES

[1] Ilia Volkov MD, Yan Press MD, Inna Rudoy MD. Vitamin B12 could be a “MASTER

KEY” in the regulation of multiple pathological processes. Journal of Nippon Medical

School. 2006;73(2): 65-69

[2] Herrmann W, Obeid R, Schorr H, Geisel J. Functional vitamin B12 deficiency and

determination of holotranscobalamin in populations at risk. Clin Chem Lab Med. 2003

Nov;41(11):1478-88.

[3] Solomon LR. Cobalamin-responsive disorders in the ambulatory care setting:

unreliability of cobalamin, methylmalonic acid, and homocysteine testing. Blood 2005;

105:978-985.

[4] Smolka V, Bekarek V, Hlidkova E et. Metabolic complications and neurologic

manifestations of vitamin B12 deficiency in children of vegetarian mothers. Cas Lek

Cesk. 2001 Nov 22;140(23):732-5.

[5] Muthayya S, Dwarkanath P, Mhaskar M, Mhaskar R, Thomas A, Duggan C, Fawzi

WW, Bhat S, Vaz M, Kurpad A. The relationship of neonatal serum vitamin B12 status

with birth weight. Asia Pac J Clin Nutr. 2006 Dec;15(4):538-543.

[6] Groenen PM, van Rooij IA, Peer PG. Marginal maternal vitamin B(12) status increases

the risk of an offspring with spina bifida. Am J Obstet Gynecol. 2004 Jul;191(1):11-7

The Role and Status of Vitamin B12: Need for Clinical Reevaluation and Change 187

[7] Ambroszkiewicz J, Laskowska-Klita T, Klemarczyk W. Low levels of osteocalcin and

leptin in serum of vegetarian prepubertal children. Med Wieku Rozwoj. 2003 OctDec;7(4 Pt 2):587-91.

[8] Brasseur D. Excessive dietetic restrictions in children. Rev Med Brux. 2000

Sep;21(4):A367-70.

[9] Healton EB, Savage DG, Brust JC, Carett TJ, Lindenbaum J Neurologic aspects of

cobalamin deficiency. Medicine (Baltimore). 1991 Jul;70(4):229-45.

 

VITAMIN B12 AND DEVELOPMENT

Many research studies emphasize the health complications of nutritional cobalamine

deficiency and a necessity of clinical, biochemical and metabolic monitoring in infants born

to mothers suffering from vitamin B12 deficiency. Dietary deficiencies of vitamin B12 during

pregnancy and lactation may result in health problems in exclusively breastfed infants.

Physical examination of these children have revealed psychomotoric retardation, apathy,

muscular hypotonia, irritability, anorexia, abnormal movements and failure to thrive.

Laboratory analysis show haematological abnormalities, such as a megaloblastic anaemia, a

low level of vitamin B12, high level of homocystein and methylmalonic acid and

methylmalonic aciduria. MRI of the brain reveals diffuse frontotemporoparietal atrophy and

retardation of myelination [4]. Some studies have shown a relationship between maternal

vitamin B12 status and birth weight. One of them extends those findings directly in terms of

neonatal vitamin B12 status and birth weight. Vitamin B12 status in the mother was related to

neonatal vitamin B12 status as measured by cord serum vitamin B12 concentration. In

addition, low neonatal vitamin B12 concentrations were adversely associated with low birth

weights [5]. A marginal maternal vitamin B12 status increases the risk of an offspring with

spina bifida [6].

There are different vegetarian dietary patterns, some of which are nutritionally adequate

for children. However, others may lack essential nutrients. Lack of animal products in the

diet decreases the intake of essential nutrients which may influence bone metabolism. This is

a very serious problem, especially in childhood and adolescence when growth and bone

turnover are the most intensive. Bone metabolism is regulated by variety factors, which are

involved in the bone formation and bone re-absorption processes. Osteocalcin is one of the

markers of bone formation (produced by osteoblast) which plays an important role in the

regulation of bone growth. Recent data support the concept that other modulators, such as

leptin (a hormone from adipose tissue), play an important role in the control of body fat

storage and energy expenditure. Higher leptin levels were observed in obese subjects and

lower levels in anorectic patients. Lower levels of osteocalcin and leptin are accompanied by

lower vitamin B12 concentration may retard relevant bone growth and development in

childhood [7].

Children have specific and increased nutritional requirements in comparison with adults.

Rapid growth and enhanced energy expenditure explain these differences. Any diet deviation

178 Ilia Volkov, Inna Rudoy and Yan Press

will increase exposure to the risk of nutritional deficiency along with corresponding health

consequences. Whenever a diet restriction for children is required for medical reasons,

particular attention must be paid to the food regimen in order to avoid any health problem,

especially growth retardation [8].

COBALAMIN-RESPONSIVE

NEUROPSYCHOLOGICAL CONDITIONS

The only function that has been indicated as unique for vitamin B 12 is the synthesis of

myelin, a component of the sheaths that protect nerve fibers. Vitamin B12 deficiency can

cause peripheral neuropathy and combined system diseases involving demyelination of the

dorsal columns and the corticospinal tract. In most episodes neurological complaints,

commonly paresthesias or ataxia, is the first symptom of cobalamin deficiency. The median

duration of symptoms between diagnosis and treatment with vitamin B12 is a few months,

although in some patients there are longer delays in diagnosis. Diminished vibratory

sensation and proprioception in the lower extremities are the most common objective

findings. A wide variety of neuropsychological symptoms and signs have been encountered,

such as ataxia, loss of cutaneous sensation, muscle weakness, diminished or hyperactive

reflexes, spasticity, urinary or fecal incontinence, orthostatic hypotension, loss of vision,

dementia, psychoses, and disturbances of mood. Multiple neurological syndromes were often

seen in a single patient. Severity of neurological dysfunction before treatment is clearly

related to the duration of symptoms prior to diagnosis [9].

Recurrent seizures, extrapyramidal system involvement in the form of involuntary

movements (myoclonus-like involuntary movements, chorea and focal dystonia) or acute

onset parkinsonism have been reported as a rare manifestations of vitamin B12 deficiency

[10,11,12,13].

Optic nerve involvement is a rare but recognized appearance of vitamin B12 deficiency,

which may proceed to visual failure if not diagnosed early enough.

MRI examination typically demonstrates involvement of the cervical cord in majority of

the patients, although the pathology sometimes begins in the thoracic cord. MRI also has

demonstrated contiguous involvement of multiple segments of the cord. The cord

abnormality can resolve without evidence of cord atrophy on MRI, if treated early.

Multiple Sclerosis (MS) and vitamin B12 deficiency share common inflammatory and

neurodegenerative pathophysiological characteristics. Due to similarities in the clinical

presentations and MRI findings, the differential diagnosis between vitamin B12 deficiency

and MS may be difficult. Additionally, low or decreased levels of vitamin B12 have been

demonstrated in MS patients. Moreover, recent studies suggest that vitamin B12, in addition

to its known role as a co-factor in myelin formation, has important immunomodulatory and

neurotrophic effects. These observations raise the questions of possible causal relationship

between the two disorders, and suggest further studies of the need to monitor closely vitamin

B12 levels in MS patients, as well as potentially requiring supplementation of vitamin B12

alone or in combination with the immunotherapies [14]. Interferon-beta is a mainstay therapy

of demyelinating diseases, but it has only a partial effect on multiple sclerosis in humans and

The Role and Status of Vitamin B12: Need for Clinical Reevaluation and Change 179

in several animal models of the disease. In a recent report the authors demonstrated a

dramatic improvement in the clinical, histological, and laboratory parameters of disease in in

vivo mouse models of demyelinating disease. This was seen following combination therapy

with IFN-beta and vitamin B12 cyanocobalamin [B(12)CN] in non-autoimmune primary

demyelinating ND4 (DM20) transgenic mice, and in acute and chronic experimental

autoimmune encephalomyelitis in mice. Clinical improvement, manifested as near normal

motor function, was associated with reduced astrocytosis and demyelination. IFN-betaB12CN combination therapy may be promising for the treatment of multiple sclerosis [15].

The association of cobalamin deficiency with psychiatric illness has been studied and

debated since this vitamin was first discovered in the 1940s. The clinical relevance of this

deficiency remains the subject of investigation and academic discussion. Vitamin B12 has

fundamental roles in brain function. Intracellular cobalamin is converted to

adenosylcobalamin, coenzyme for methylmalonyl-CoA mutase and to methylcobalamin,

coenzyme for methionine synthase which mediates conversion of homocysteine to

methionine. This leads to an increase in the level of homocysteine (Hcy). Homocysteine has

been implicated as a risk factor for vascular disease, as well as brain atrophy. There is

evidence to implicate Hcy in increased oxidative stress, DNA damage, the triggering of

apoptosis and excitotoxicity, all of which are important mechanisms in neurodegeneration.

Hcy is also prothrombotic and proatherogenic, and causes damage to the vessel wall and is

related to brain atrophy, and possibly to white matter hyperintensities in the brain.

Epidemiological evidence and longitudinal data support the finding that Hcy is a risk factor

for cognitive impairment and Alzheimer's Disease [16,17,18]. This may be due to

cerebrovascular as well as direct neurotoxic mechanisms.

As well as cognitive impairment, the common psychiatric symptoms of vitamin B12

deficiency are continuous depression [19], psychotic symptoms [20], mania, and obsessive

compulsive disorder. The neuropsychiatric severity of vitamin B12 deficiency and the

therapeutic efficacy depends on the duration of signs and symptoms. Therefore, the

consideration of B12 deficiency and testing for serum B12 levels is recommended in all the

patients with organic brain syndrome, atypical psychiatric symptoms and fluctuation of

symptomatology.

RELATIONSHIP OF VITAMIN B12 AND HOMOCYSTEINE IS

THEIR FUNCTION IN CARDIOVASCULAR EVENTS OBVIOUS?

No doubt about the association between vitamin B12 and homocysteinemia [21,22], but

their synergistic or separated role in the development of atherosclerosis and influence on

cardiovascular events is nevertheless controversial. In observational studies, elevated plasma

total homocysteine levels have been positively associated with ischemic stroke risk

[23,24,25]. Numerous retrospective and prospective studies have revealed a consistent,

independent relationship between mild hyperhomocysteinemia and cardiovascular disease or

all-cause mortality. Starting at a plasma homocysteine concentration of approximately 10

mol/l, the risk increase follows a linear dose-response relationship with no specific

threshold level. Hyperhomocysteinemia, as an independent risk factor for cardiovascular

180 Ilia Volkov, Inna Rudoy and Yan Press

disease, is thought to be responsible for approximately 10% of the total risk. Elevated plasma

homocysteine levels (>12 mol /l; moderate hyperhomocysteinemia) are considered cytotoxic

and are found in 5-10% of the general population and in up to 40% of patients with vascular

disease. Based on various calculation models, reduction of elevated plasma homocysteine

concentrations may theoretically prevent up to 25% of cardiovascular events. Treatment of

hyperhomocysteinemia is recommended for the apparently healthy general population [26].

Some large studies confirm that a supplementation with group B vitamins did not reduce the

risk of major cardiovascular events or all-cause mortality in patients with vascular disease

[27,28]. We suppose, the outcomes of these and similar trials could be different if the

researches had paid attention to the following points: 1. Using vitamin B12 or B-complex as

secondary prevention of cardiovascular events for patients with irreversible changes of blood

vessels is probably in error. Rather vitamin B12 or B-complex should be used as primary

prevention! 2. Using high doses of vitamin B12 will probably be more effective than using

"group B vitamins". Furthermore, using folic acid alone for prevention of cardiovascular

diseases has been proven to be ineffective [29], while very high doses of vitamin B12 (60 mg

every day for 6 months) has been used effectively without any toxic side effects for the

treatment of other diseases [30].

MYTHS AND REALITY ABOUT

HEMATOLOGICAL ABNORMALITIES

Hemopoesis is the process in which new blood cells are produced, in which Vitamin B12,

folate, and iron have fundamental roles. New erythrocytes replace the oldest erythrocytes

(normally about one percent) that are phagocytosed and destroyed each day. Erythroblasts

require folate and vitamin B12 for proliferation during their differentiation. Deficiency of

folate or vitamin B12 inhibit purine and thymidylate syntheses, impairs DNA synthesis, and

causes erythroblast apoptosis, resulting in megaloblastic anemia from ineffective

erythropoiesis. The presence of macro-ovalocytes having a high MCV, anisocytosis,

poikilocytosis and hypersegmented neutrophils, anemia, leukopenia, and thrombocytopenia

or pancytopenia suggests a megaloblastic disorder associated with a nutritional deficiency,

i.e., vitamin B12.

During last decades, the hematological manifestations related to cobalamin deficiency

have been differed from descriptions reported in textbooks or"old" studies. Dr. Alan L

Diamond made one of a number of attempts to systematize standard knowledge as follows

[31]: "Vitamin B12 deficiency produces the classic picture of macrocytic anemia, with a mean

corpuscular value (MCV) greater than 100 fL. The MCV correlates with estimated vitamin

B12 level: MCV of 80-100 fL indicates less than 25% probability of vitamin B12 deficiency

MCV of 115-129 fL indicates a 50% propability; MCV greater 130 indicates 100%

propability." It's a classic "textbook" picture of vitamin B12 deficiency. But as far as we

know, our patients don't read a textbook… It is well known now vitamin B12 deficiency may

be accompanied by iron deficiency, and this association could have masked the macrocytosis

[32,33].

The Role and Status of Vitamin B12: Need for Clinical Reevaluation and Change 181

Vitamin B12 deficiency has many causes, and pernicious anemia has been described as a

widespread cause of vitamin B12 deficiency. The term "pernicious anemia" applies only to the

condition associated with chronic atrophic gastritis. A some population researches revealed

that 1.9 percent of persons more than 60 years old have undiagnosed pernicious anemia [34].

Although the disease may be silent until the obvious end stage, the underlying gastric lesion

can be predicted many years before anemia develops. The discovery of a serum inhibitor of

intrinsic factor (later found to be an autoantibody to the intrinsic factor) and of autoantibodies

to parietal cells laid the foundation for the immunologic explanation of the underlying

gastritis that causes pernicious anemia. The vitamin B12–intrinsic factor complex is carried to

the terminal ileum, where it is absorbed after binding to intrinsic-factor receptors on the

luminal membranes of ileal cells. Malabsorption of vitamin B12 in patients with pernicious

anemia is due to intrinsic-factor deficiency. Two mechanisms are responsible. First, the

progressive destruction and eventual loss of parietal cells from the gastric mucosa lead to

failure of intrinsic-factor production. Indeed, the severity of the gastric lesion correlates with

the degree of impaired secretion of intrinsic factor and the reduction in vitamin B12

absorption. Second, blocking autoantibodies present in the gastric juice can bind to the

vitamin B12–binding site of intrinsic factor, thereby preventing the formation of the vitamin

B12–intrinsic factor complex. Vitamin B12 is required for DNA synthesis. Therefore, the

major organs affected by vitamin B12 deficiency are those in which cell turnover is rapid,

such as the bone marrow and the gastrointestinal tract [35]. The usual presentation

accompany symptoms of anemia; asymptomatic patients can be identified by routine

hematologic investigations. But hematological abnormalities, such as anemia may be absent

at the time of neurological presentation [3].

Examination of bone marrow reveals megaloblasts and large myeloid precursors.

Current studies on cobalamin deficiency, including more precise definitions and the

description of new etiologies of cobalamin deficiency, such as insufficient dietary intake

[33], food-cobalamin malabsorption syndrome [36,37] (characterized by the inability to

release cobalamin from food or a deficiency of intestinal cobalamin transport proteins or

both) due to chronic carriage of helicobacter pylori [38] and intestinal microbial proliferation,

which can be caused by antibiotic treatment, long-term ingestion of biguanides (metformin)

[39,40] and antacids, including H2-receptor antagonists and proton pump inhibitors [41]

(particularly among patients with Zollinger–Ellison syndrome [42]), chronic alcoholism,

surgery or gastric reconstruction (e.g., bypass surgery for obesity), partial pancreatic exocrine

failure, hereditary cobalamin metabolism diseases as Imerslund-Grasbeck syndrome [43]

(selective vitamin B12 malabsorption with proteinuria) show that hematological abnormalities

are generally incomplete, as compared to historical descriptions.

Vitamin B12 deficiency may also influence the granulocyte and platelet lines and may be

mistaken for leukaemia [44] in all cases the important practical indicator is positive response

to vitamin B12 treatment.

Some European countries have deferred the decision to introduce food fortification with

folic acid for prevention of neural tube defects and other congenital anomalies because of

concerns about potential masking of vitamin B12 deficiency [45].

182 Ilia Volkov, Inna Rudoy and Yan Press

KNOWN CUTANEOUS AND MUCOUS MANIFESTATIONS OF

VITAMIN B12 DEFICIENCY AND THE NOVEL

USE OF VITAMIN B12 IN DERMATOLOGY

The characteristic dermatological sign of vitamin B12 deficiency is cutaneous

pigmentation [46,47,48,49], which can be reversed by administration of vitamin B12 .

Increased cutaneous pigmentation is especially accentuated in palmar creases, on the dorsa of

hands and feet, in intertriginous areas, on oral mucosa and in recent scars. The mechanism of

hyperpigmentation is unexplained. Histology showed an increase of melanin in the basal

layer. In electron microscopic study, many melanosomes were observed in melanocytes and

surrounding keratinocytes. There is supposition that the dominant mechanism of

hyperpigmentation due to vitamin B12 deficiency is not a defect in melanin transport, but is

rather an increase in melanin synthesis.

We investigated and reported a case of the paradoxical disappearance of chronic

erythema nodosum [50], which had persisted for more than half a year in spite of a prolonged

treatment with non-steroidal anti-inflammatory drugs. When the patient complained of

paresthesias, a blood test for vitamin B12 was performed and a prominent vitamin B12

deficiency was discovered. Since treatment was initiated with intramuscular vitamin B12

injections, not only did the paresthesias disappear, but the erythema nodosum, as well. The

patient continued to receive maintenance therapy with vitamin B12 without recurrence of

erythema nodosum.

 The human hepatic tumor cells (Bel-7204) with different concentrations of 5-Fu-PAEAPM (the content of polymeric drug (wt%): 5-Fu 25.6, PM 3.3) in the growth medium in

culture were incubated for 24h in incubator (37℃, 5% CO2). Induction of apoptosis was

confirmed by formation of apoptotic bodies and fragmentation of cellular DNA (Figure 16).

5-Fu-PAEA-PM at 18µg/ml, 36µg/ml, 62.5µg/ml and 135µg/ml concentration induced

apoptosis in about 27.6%, 43.1%, 50.7% and 62%, respectively, of human hepatic tumor cells

168 Guo-Ping Yan, Xiao-Yan Wang, Li-Li Mei

after 48h incubation. When the concentration of 5-Fu-PAEA-PM (3) increased, the

percentage of apoptosis in the human hepatic tumor cells became considerably larger. The

apoptosis experiments showed the polymeric drugs could exhibit obviously high anticancer

efficiencies and induce apoptosis in the human hepatic tumor cells (Bel-7204).

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70

80

90

100

Viability Relative to Control (%)

Concentration (¦Ì g/mL)

 5-Fu-PAEA-PM (3)

 FT-207

Figure 15. Cytotoxicity assay of anticancer drugs in L-02 cells.

 A B

Figure 16. Induced apoptosis photo of 5-Fu-PAEA-PM in the human hepatic tumor cells. A: control

cells; B: 5-Fu-PAEA-PM (the content of polymeric drug (wt%): 5-Fu 25.6, PM 3.3) (135µg/mL).

SUMMARY

Although the liver-targeting mechanism and kinetic procedure of vitamin B6 for MRI

contrast agent and drug delivery have not described detailedly, previous researches have

demonstrated that the incorporation of pyridoxine into MRI contrast agent and anticancer

conjugates can increase their uptake by the liver, and that these molecules containing

Vitamin B6 as Liver-targeting Group in Drug Delivery 169

pyridoxine groups exhibit liver-targeting properties. Thus it is important to come to devote

greater efforts to solving these problems.

One important approach in drug design for the disease in the liver is that the drugs can be

targeted to the liver. By this method, the toxic side effects of the drugs can be suppressed and

the distribution of drugs will be changed after administered, to improve the efficiency toward

malignant cells and reduce the drugs dose. In future, the ideal drugs will be focused on the

liver-targeting property with low toxicity and side effect, low doses in vivo, and minimal cost

of procedure.

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In: Vitamin B: New Research ISBN: 978-1-60021-782-1

Editor: C. M. Elliot, pp. 175-191 © 2008 Nova Science Publishers, Inc.

Chapter X

THE ROLE AND STATUS OF VITAMIN B12:

NEED FOR CLINICAL

REEVALUATION AND CHANGE

Ilia Volkov∗ , Inna Rudoy and Yan Press

Department of Family Medicine, Faculty of Health Sciences, Ben-Gurion University of

the Negev, Beer-Sheva, Israel.

ABSTRACT

Vitamin B12 plays a functional role in a variety of organs and body systems and the

list of these organs and body systems is growing. It affects the peripheral and central

nervous systems, bone marrow, skin and mucous membranes, bones, and vessels, as well

as the normal development of children. Vitamin B12 (cobalamin) is unique among all the

vitamins in that it contains not only a complex organic molecule but also an essential

trace element, cobalt. Vitamin B12 plays an important role in DNA synthesis and has

important immunomodulatory and neurotrophic effects. According to our “working

hypothesis” a vitamin B12 has some unique, but still unrecognized functions.

Multifunctional systems in the human body need to maintain homeostasis. Man is an

ideal example of a system that constantly aspires to attain optimal regulation, even under

the stress of severe pathology. We assume that there are universal, interchangeable (as

required) propose that one of these substances is vitamin B12.Why vitamin B12? It is

possible that even when the serum cobalamin level is normal, treatment with vitamin B12

can correct defects caused by other biologically active substances. In our studies this has

been proved successful in the treatment of recurrent aphthous stomatitis with vitamin B12

(irrespective of its blood level!). We call this phenomenon the “Master Key” effect.

Vitamin B12 deficiency is a common problem that affects the general population.

Early detection of vitamin B12 deficiency is clinically important, and there is evidence

∗

 Correspondence concerning this article should be addressed to Dr. Ilia Volkov, Lea Imenu St. 59/2, Beer-Sheva,

84514, Israel. Tel: 972-8-6431530; Cell phone: 972-54-7829623; Fax: 972-8-6413135; E-mail:

r0019@zahav.net.il.

176 Ilia Volkov, Inna Rudoy and Yan Press

that such deficiency occurs more frequently than would be expected. Vitamin B12

deficiency can occur in individuals with dietary patterns that exclude animal foods and

patients who are unable to absorb vitamin B12 in food. In addition there is an overall

tendency to avoid eating those foods which are high in Vitamin B12, such as beef,

because of the relationship between meat, cholesterol and cardiovascular diseases. Also

there is a tendency, particularly among the younger generation, to be vegetarians for

ideological motives. Changes in life style among segments of the population with high

socioeconomic level, on one hand, and the existence of poverty, on the other, are two

main factors in the decreasing consumption of animal products, particularly red meat.

Thus, there is a decrease in the level of vitamin B12 in general population, and as a

consequence, an increase in pathology due to vitamin B12 deficiency (such as

neurological and hematological disorders). If future research will corroborate the

relationship between vitamin B12 and homocystein, we may observe an increase in

cardiovascular disease as well. In lieu of these developments and in order to prevent

serious health problems, vitamin B12 fortification should be seriously considered and

discussed.

BACKGROUND

Vitamin B12 plays a functional role in a variety of organs and body systems and the list of

these organs and body systems is growing. It affects the peripheral and central nervous

systems, bone marrow, skin and mucous membranes, bones, and vessels, as well as the

normal development of children. Vitamin B12 (cobalamin) is unique among all the vitamins

in that it contains not only a complex organic molecule but also an essential trace element,

cobalt. Vitamin B12 plays an important role in DNA synthesis and has important

immunomodulatory and neurotrophic effects. According to our “working hypothesis” a

vitamin B12 has some unique, but still unrecognized functions.

Multifunctional systems in the human body need to maintain homeostasis. Man is an

ideal example of a system that constantly aspires to attain optimal regulation, even under the

stress of severe pathology. We assume that there are universal, interchangeable (as required)

propose that one of these substances is vitamin B12.Why vitamin B12? It is possible that even

when the serum cobalamin level is normal, treatment with vitamin B12 can correct defects

caused by other biologically active substances. In our studies this has been proved successful

in the treatment of recurrent aphthous stomatitis with vitamin B12 (irrespective of its blood

level!). We call this phenomenon the “Master Key” effect [1].

Vitamin B12 deficiency is a common problem. Early detection of vitamin B12 deficiency

is essential in order to prescribe opportune treatment, and there is evidence that such

deficiency occurs more frequently than would be expected. Vitamin B12 deficiency can occur

in individuals with dietary patterns that exclude animal food products and patients who are

unable to absorb vitamin B12. Persons with B12 deficiency may be asymptomatic, but in

patients presenting with myelopathy, cognitive decline, neuropathy, psychiatric disturbances

or specific hematological signs and symptoms, B12 deficiency should be suspected. There are

no generally accepted guidelines for the definition, diagnosis, treatment, and follow-up of

cobalamin deficiency. Total serum vitamin B12 may not reliably indicate vitamin B12 status.

Probability of "functional" vitamin B12 deficiency decreases upon increasing the blood level

The Role and Status of Vitamin B12: Need for Clinical Reevaluation and Change 177

of vitamin B12. To increase specifity and sensitivity in diagnosing vitamin B12 deficiency, the

concept of measuring homocystein (HCY), methylmalonic acid (MMA), holotranscobalamin

II (holoTC),- a sub-fraction of vitamin B12, has aroused great interest. HoloTC, as a

biologically active vitamin B12 fraction, promotes uptake of its vitamin B12 by all cells [2].

However, diagnostic algorithms using vitamin B12, MMA, and HCY measurements reflect

studies in some academic centers, and their negative predictive values have not been

established. Therefore, this problem remains controversial [3].

We will attempt to demonstrate vitamin B12 critical roles by surveying and analyzing

available reports, as well as reporting our own clinical experience.