Life Extension Magazine®

Issue: Dec 2000

Cancer Prevention, Vitamin B12, CLA, more


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Page 1 of 2

Cancer Prevention

Inhibitory effect of curcumin on epidermal growth factor receptor kinase activity in A431 cells

We explored the mechanism of antigrowth action of Curcumin by investigating its effect on epidermal growth factor (EGF) receptor intrinsic kinase activity in the human epidermoid carcinoma A431 cells. The short-term treatment of cells with Curcumin inhibited EGF receptor intrinsic kinase activity up to 90% in a dose- and time-dependent manner, and also inhibited EGF-induced tyrosine phosphorylation of EGF receptors. The observed early effects of Curcumin were mediated via a cellular mechanism(s), and preceded the period when inhibition of cell growth occurred.

Biochim Biophys Acta 1994 Dec 30;1224(3):597-600

Inhibition of ligand-induced activation of epidermal growth factor receptor tyrosine phosphorylation by curcumin

We explored the regulation of epidermal growth factor (EGF)-mediated activation of EGF receptor (EGF-R) phosphorylation by curcumin (diferuloyl-methane), a recently identified kinase inhibitor, in cultured NIH 3T3 cells expressing human EGF-R. Treatment of cells with a saturating concentration of EGF for 5-15 min induced increased EGF-R tyrosine phosphorylation by 4- to 11-fold and this was inhibited in a dose- and time-dependent manner by up to 90% by curcumin, which also inhibited the growth of EGF-stimulated cells. There was no effect of curcumin treatment on the amount of surface expression of labeled EGF-R and inhibition of EGF-mediated tyrosine phosphorylation of EGF-R by curcumin was mediated by a reversible mechanism. In addition, curcumin also inhibited EGF-induced, but not bradykinin-induced, calcium release. These findings demonstrate that curcumin is a potent inhibitor of a growth stimulatory pathway, the ligand-induced activation of EGF-R, and may potentially be useful in developing anti-proliferative strategies to control tumor cell growth.

Carcinogenesis 1995 Aug;16(8):1741-5

New agents for cancer chemoprevention

Clinical chemoprevention trials of more than 30 agents and agent combinations are now in progress or being planned. The most advanced agents are well known and are in large Phase III chemoprevention intervention trials or epidemiological studies. These drugs include several retinoids [e.g., retinol, retinyl palmitate, all-trans-retinoic acid, and 13-cis-retinoic acid], calcium, Beta carotene, vitamin E, tamoxifen, and finasteride. Other newer agents are currently being evaluated in or being considered for Phase II and early Phase III chemoprevention trials. Prominent in this group are all-trans-N-(4-hydroxy phenyl) retinamide (4-HPR) (alone and in combination with tamoxifen), 2-difluoromethylornithine (DFMO), nonsteroidal anti-inflammatory drugs (aspirin, piroxicam, sulindac), oltipraz, and dehydroepiandrostenedione (DHEA). A third group is new agents showing chemopreventive activity in animal models, epidemiological studies, or in pilot clinical intervention studies. They are now in preclinical toxicology testing or Phase I safety and pharmacokinetics trials preparatory to chemoprevention efficacy trials. These agents include S-allyl-l-cysteine, curcumin, DHEA analog 8354 (fluasterone), genistein, ibuprofen, indole-3-carbinol, perillyl alcohol, phenethyl isothiocyanate, 9-cis-retinoic acid, sulindac sulfone, tea extracts, ursodiol, vitamin D analogs, and p-xylyl selenocyanate. A new generation of agents and agent combinations will soon enter clinical chemoprevention studies based primarily on promising chemopreventive activity in animal models and in mechanistic studies. Among these agents are more efficacious analogs of known chemopreventive drugs including novel carotenoids (e.g., alpha-carotene and lutein). Also included are safer analogs which retain the chemopreventive efficacy of the parent drug such as vitamin D3 analogs. Other agents of high interest are aromatase inhibitors (e.g., (+)-vorozole), and protease inhibitors (e.g., Bowman-Birk soybean trypsin inhibitor). Combinations are also being considered, such as vitamin E with l-selenomethionine. Analysis of signal transduction pathways is beginning to yield classes of potentially active and selective chemopreventive drugs. Examples are ras isoprenylation and epidermal growth factor receptor inhibitors.

J Cell Biochem Suppl 1996;26:1-28

Therapeutic potential of curcumin in human prostate cancer. II. Curcumin inhibits tyrosine kinase activity of epidermal growth factor receptor and depletes the protein

Purpose: In a search for alternative and preventive therapies for prostate cancer, attention was focused on the ways in which curcumin (Turmeric), used in food and medicine in India for centuries, could interfere with the growth factor signaling pathways in both androgen-dependent and androgen-independent prostate cancer cells, as exemplified by the epidermal growth factor receptor (EGF-R) signaling. Materials and Methods: The androgen-sensitive LNCaP and androgen-insensitive PC-3 cell lines were grown in 5 to 50 &mgr;M curcumin and analyzed for EGF-R protein by Western blotting and for EGF-R tyrosine kinase activity. Results: Curcumin was a potent inhibitor of EGF-R signaling, and it accomplished this effect by three different means (1) down regulating the EGF-R protein; (2) inhibiting the intrinsic EGF-R tyrosine kinase activity; and (3) inhibiting the ligand-induced activation of the EGF-R. Conclusions: These results, taken together with our previous results that curcumin can induce apoptosis in both androgen-dependent and androgen-independent prostate cancer cells, support our view that curcumin may be a novel modality by which one can interfere with the signal transduction pathways of the prostate cancer cell and prevent it from progressing to its hormone-refractory state.

Mol Urol 2000 Spring;4(1):1-6

The role of induction chemotherapy in the curative treatment of squamous cell cancer of the head and neck

Induction chemotherapy is appropriate for the treatment of locally advanced squamous cell carcinoma of the head and neck because it allows organ preservation without compromising survival and improves survival in unresectable disease. Radiation therapy, not surgery, should immediately follow induction chemotherapy in potentially resectable patients to prevent tumor repopulation. The results of three phase II studies of docetaxel-based regimens as induction therapy of patients with locally advanced squamous cell carcinoma of the head and neck are reviewed and reported. Overall response rates ranged from 93% to 100%, with complete response rates of 40% to 63%. The primary toxicities were neutropenia and febrile neutropenia. A North American phase III trial, randomizing patients to docetaxel/cisplatin/fluorouracil or cisplatin/fluorouracil sequentially followed by chemoradiotherapy is being performed to determine whether docetaxel improves the complete response rate, organ preservation rate, and survival of patients treated with induction chemotherapy.

Semin Oncol 2000 Aug;27(4 Suppl 8):13-24

Steroid hormones induce HMG1 overexpression and sensitize breast cancer cells to cisplatin and carboplatin

Cisplatin is an anticancer drug that has enjoyed remarkable success against testicular tumors, but dose limiting side-effects have limited its application against a broader range of cancers. Previous studies have shown that high-mobility group (HMG) domain proteins such as HMG1 sensitize cells to cisplatin by shielding its major DNA adducts from nucleotide excision repair. Estrogen treatment increases HMG1 mRNA levels in breast cancer MCF-7 cells. Herein, we describe that treatment of human cancer cells having steroid hormone receptors with the appropriate hormone, estrogen and/or progesterone, significantly increases the potency of cisplatin and its analogue carboplatin by causing the overexpression of HMG1. These findings suggest that the proper combination of these drugs, which are already approved by the Food and Drug Administration, could have potential benefit in treating tumors such as ovarian or breast that carry the hormone receptors.

Proc Natl Acad Sci U S A 2000 May 23;97(11):5768-72

Methionine depletion enhances the antitumoral efficacy of cytotoxic agents in drug-resistant human tumor xenografts

Efficacy of chemotherapy is limited in numerous tumors by specific cellular mechanisms that inactivate cytotoxic antitumoral drugs, such as ATP-dependent drug efflux and/or drug detoxification by glutathione. In reducing ATP pools and/or glutathione synthesis, it might be possible to enhance the efficacy of drugs affected by such resistance mechanisms. Reduction of the ATP pool and glutathione content is achievable in cancer cells by depleting the exogenous methionine (Met) supply and ethionine. Thus, the rationale for the present study was to use Met depletion to decrease the ATP and glutathione pools so as to sensitize tumors refractory to cytotoxic anticancer drugs. Met depletion was achieved by feeding mice a methionine-free diet supplemented with homocysteine. The effects of Met depletion combined with ethionine and/or chemotherapeutic agents were studied using human solid cancers xenografted into nude mice. TC71-MA (a colon cancer) SCLC6 (a small cell lung cancer), and SNB19 (a glioma) were found to be refractory to cisplatin, doxorubicin, and carmustine, respectively. These three drugs are used to treat such tumors and are dependent for their activity on the lack of cellular ATP- or glutathione-dependent mechanisms of resistance. TC71-MA, SCLC6, and SNB19 were Met dependent because their proliferation in vitro and growth in vivo were reduced by Met depletion. Cisplatin was inactive in the treatment of TC71-MA colon cancer, whereas a methionine-free diet, alone or in combination with ethionine, prolonged the survival of mice by 2-fold and 2.8-fold, respectively. When all three approaches were combined, survival was prolonged by 3.3-fold. Doxorubicin did not affect the growth of SCLC6, a MDR1-MRP-expressing tumor. A Met-deprived diet and ethionine slightly decreased SCLC6 growth and, in combination with doxorubicin, an inhibition of 51% was obtained, with survival prolonged by 1.7-fold. Combined treatment produced greater tumor growth inhibition (74%) in SCLC6-Dox, a SCLC6 tumor pretreated with doxorubicin. Growth of SNB19 glioma was not inhibited by carmustine, but when it was combined with Met depletion, survival duration was prolonged by 2-fold, with a growth inhibition of 80%. These results indicate the potential of Met depletion to enhance the antitumoral effects of chemotherapeutic agents on drug-refractory tumors.

Clin Cancer Res 2000 Feb;6(2):643-53

Therapeutic effect of intralesional interferon (Roferon) in squamous cell carcinoma

Recombinant alpha-2 interferon (IFN)*Roferon*100,000 IU/ml was intralesionally administered in 8 cases of squamous cell carcinoma (SCC) three times a week during 4-6 weeks in inoculations of 1 ml each. The therapeutic effect was scored as major-more than 60% reduction of the tumor size, moderate*30-60% reduction of the tumor mass and, nonreactive*less than 30% reduction of the tumor size. Three cases showed a major reduction, three showed a moderate reduction and two patients showed no reduction of the tumor volume. Histopathological examination of the surgically removed tumors after completion of the Roferon administration confirmed the clinical diagnosis of squamous cell carcinoma and revealed that an intense leukocyte, mainly lymphocytes, infiltration can be observed along with necrotic centers, progressively surrounding and reducing in size the tumor islets, thus proving an intense activation of the immune effector reactions against tumor cells.

Rom J Intern Med 1992 Jul-Sep;30(3):207-10

Preliminary trial of nonrecombinant interferon alpha in recurrent squamous cell carcinoma of the head and neck

Fourteen patients with recurrent squamous cell carcinoma of the head and neck (SCCHN) were treated with 10 x 10(6) U of nonrecombinant interferon alpha (IFN) intramuscularly (IM) daily for 3 days every 28 days. There were 11 men and 3 women, with ages ranging from 48 to 74 years. Patients had previously been treated with surgery (9 patients), radiotherapy (13 patients), or chemotherapy (8 patients). All patients had measurable disease by physical exam and radiologic evaluation and a performance status of less than or equal to 2 (ECOG). Patients were treated for a minimum of 3 months and continued on therapy until disease progression. The dose and treatment schedule of IFN was well-tolerated. Toxicities included low-grade fever, mild anorexia, and malaise. Treatment was stopped in 1 patient due to the development of atrial fibrillation. One death occurred as a complication of aspiration pneumonia 2 weeks following the onset of therapy and was not felt to be related to IFN therapy. Of the 14 patients treated, there was 1 complete response (30+ months) of a base of tongue primary. Two patients had stabilization of disease (SD, 8 and 12 months). One patient had a mixed response with resolution of subcutaneous nodules. The remaining 10 patients died of progressive disease. Immunological assessment was performed on 8 patients. The 1 patient who had a complete response was noted to have markedly low pretreatment natural killer (NK) cell activity and a subsequent sharp rise in activity after initial treatment. We conclude that low-dose cyclic IFN is well-tolerated in patients with recurrent SCCHN and has potential antitumor activity.

Head Neck 1991 Jan-Feb;13(1):15-21

Interferon therapy for basal cell carcinoma and squamous cell carcinoma

Totally 161 basal cell and squamous cell carcinoma (BCC, SCC) patients were treated with human natural leucocytic interferon (HNLI) and recombinant IFN alpha 2c. After HNLI treatment, 61 out of 86 BCC patients and 29 out of 45 SCC patients were cured according to histopathologic and clinical findings. In 13 BCC and 13 SCC patients, the cancer lesion was reduced 25%-90%. After recombinant IFN alpha 2c treatment, 14 of 20 BCC patients and 4 of 10 SCC patients were cured according to histopathologic and clinical findings. In 6 BCC patients and 5 SCC patients the cancer lesion was reduced 25% to 90%. Both types of interferons are effective in the treatment of BCC and SCC patients. Local application of interferon stimulates immune reaction at the site of the tumor. There is a marked difference between the spontaneous macrophage activity and that induced by interferon. The interferon activated macrophages are significantly larger, the number of lysosomes and the density of macrophages is increased. In difficult locations intralesional therapy can be considered to avoid disfigurement of the patients with or without surgery.

Int J Clin Pharmacol Ther Toxicol 1991 Sep;29(9):342-6

Chronic myelocytic leukemia induced into remission by interferon-alpha associated with early esophageal cancer

A fifty-one-year-old male patient visited the Department of Dermatology of Toho University Ohashi Hospital with a complaint of generalized exanthema, which was diagnosed assyringoma; at that time his leukocytosis was recognized. He was admitted to our department on August 8, 1988. Physical examination on admission revealed slight hepatosplenomegaly. WBC count was elevated (50,700/microliters). He was diagnosed as having Ph1-positive CML in the chronic phase and was treated with IFN-alpha (HLBI, Sumitomo, 3 x 10(6) units/day, daily, I. M.) from August 12, but an elevated lesion was detected at the lower part of his esophagus by endoscopy, and it was diagnosed by biopsy as squamous cell carcinoma. Radical operation for esophageal cancer was performed on September 26; at that time his WBC count was 17,400/microliters. After discharge, his WBC level was maintained within normal range by IFN-alpha. On August 2, 1989, he was readmitted to our hospital because of lymphoblastic crisis. Although he attained transient complete remission, he died of pneumonia after the relapse on January 10, 1990. IFN-alpha therapy is suggested to be useful for the treatment of CML associated with gastrointestinal cancer because of its possible parenteral administration and mild toxicity.

Rinsho Ketsueki 1991 Jul;32(7):786-90

Expression of basic fibroblast growth factor protein and its down-regulation by interferons in head and neck cancer

BACKGROUND: Angiogenesis is crucial for tumor growth and metastasis. In several tumors, microvascular density has been shown to correlate with metastasis and aggressiveness. Basic fibroblast growth factor (bFGF) has potent angiogenic activity and has been identified in a wide variety of malignancies including head and neck squamous cell carcinomas (HNSCC). Material and Methods Frozen sections of 50 HNSCC were immunostained for von Willebrand factor and bFGF. Microvessels were counted by light microscopy; bFGF expression was studied at the light and electron microscopic level. Laryngeal cancer cell line HlaC79 was incubated with interferon (IFN) alpha and beta. bFGF quantification was performed by ELISA, and antiproliferative effects were determined by BrdU assay. RESULTS: The mean number of blood vessels (77.5 +/- 23.7) is significantly increased in HNSCC compared with controls (17.1 +/- 5.9). bFGF protein expression was detected in all HNSCC but not in control tissue. An correlation between bFGF expression and mean number of microvessels was found (p <.001). However, no correlation between bFGF expression and the main clinicopathologic features was shown. The long-term exposure (144 hr) of HNSCC cells to noncytostatic concentrations of IFN alpha and beta (>10 U/mL) down-regulated the protein production of bFGF. CONCLUSION: bFGF expression and angiogenesis are enhanced in HNSCC. The higher microvessel density in HNSCC with strong bFGF expression supports the importance of bFGF for tumor angiogenesis. IFN alpha and beta treatment leads to a down-regulation of bFGF expression independent of their antiproliferative effects, suggesting that IFN treatment might result in a reduction of angiogenesis in HNSCC.

Head Neck 2000 Mar;22(2):183-9

Effect of interferon-alpha (IFN alpha) on various human tumor xenografts

The growth of some human tumor xenografts (3 out of 8, melanoma, non-Hodgkin's lymphoma, squamous cell carcinoma) was successfully--but moderately and temporarily--inhibited, when interferon-alpha (EGIS, Hungary) was given for 10 days. The route of administration (intratumoral or intraperitoneal) was usually not a decisive factor. An attempt to potentiate IFNa action with Zymozan or Cyclophosphamide did not succeed.

Anticancer Res 1988 May-Jun;8(3):467-9

Gene amplification and overexpression of epidermal growth factor receptor in squamous cell carcinoma of the head and neck

The degree of gene amplification for epidermal growth factor receptor (EGFR) and its expression levels were examined in 4 cases of tumor lesions and their cell lines of human squamous cell carcinoma (SCC) of the oral cavity. The amplification was detected in 1 case (ZA), but not significantly in 3 other cases (HOC605, HOC815, and HOC927) in which the amplification did not occur during the cell line establishment. In those 3 cases, levels of EGFR synthesis and human EGF (hEGF) binding capacity were varied: HOC605 and HOC815 had slightly increased levels of hEGF binding capacity and EGFR synthesis, respectively. While HOC927 had the lowest levels of both, the hEGF binding capacity was elevated in the tumor lesion when compared with the normal counterpart of the same patient. These results suggest that the increased capacity for EGF binding plays a more important role than does gene amplification on the tumorigenesis of SCC of the head and neck.

Head Neck 1992 Jan-Feb;14(1):8-13

Characterization, quantification, and potential clinical value of the epidermal growth factor receptor in head and neck squamous cell carcinomas

Epidermal growth factor (EGF) stimulates the growth of several types of epithelial tissues and possesses a strong mitogenic activity that is mediated through its cell surface receptor (EGFR). The aim of this study was to characterize EGFR and measure its levels in head and neck tumors biopsies (70 patients); use of a simplified competition technique with a radiolabeled ligand allowed evaluation of functional EGFR. Five samples (4 tumors and 1 control) were used to characterize EGF binding. Graphic representation identified a single family of binding sites. Kd values revealed high affinity for EGF binding: mean Kd, 0.156 0.108 nM (0.095-0.347 nM). EGF-binding characteristics (Kd) were similar in nontumoral tissue samples (controls) and in tumor material. In 59 of 60 cases, EGFR levels were higher in the tumor than in the corresponding controls. A significant correlation was found between EGFR levels and tumor size and stage. Controls exhibited a trend toward higher EGFR levels in elevated sizes and stages. According to a cutoff EGFR value of 100 fmol/mg protein, which separated all controls from tumors, EGFR-positive tumors (greater than 100 fmol/mg protein) had a greater probability of complete response to chemotherapy than EGFR-negative tumors; other tumor characteristics, such as the degree of tumoral differentiation, tumor size, or stage, were unable to operate such a discrimination in the response to chemotherapy. EGFR may thus be an interesting biological marker for head and neck cancer.

Head Neck 1991 Mar-Apr;13(2):132-9

Epidermal growth factor receptor gene amplification and expression in head and neck cancer cell lines

We studied epidermal growth factor receptor (EGFR) gene amplification and expression in 11 early passage human head and neck carcinoma cell lines. Three cell lines demonstrated EGFR gene amplification and 10 lines showed an increase in EGFR mRNA when compared with normal keratinocytes, placenta, and a human skin carcinoma cell line. The effects of EGF on growth in 6 head and neck carcinoma cell lines was also studied. Growth inhibition at a concentration of 20 ng/mL was observed in one cell line but had no effect on growth in 5 cell lines. An increase in EGFR may be important in the etiology of, or progression of, head and neck carcinoma although the mechanisms need to be elucidated by further study.

Head Neck 1989 Sep-Oct;11(5):437-42





 



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Page 2 of 2

B12

Methylcobalamin treatment of Bell's palsy

Sixty patients with Bell's palsy were included in an open randomized trial. Patients were assigned into three treatment groups: steroid (group 1), methylcobalamin (group 2) and methylcobalamin + steroid (group 3). Comparison between the three groups was based on the number of days needed to attain full recovery, facial nerve scores, and improvement of concomitant symptoms. The time required for complete recovery of facial nerve function was significantly shorter ( p < 0.001) in the methylcobalamin (mean of 1.95 +/- 0.51 weeks) and methylcobalamin plus steroid groups (mean of 2.05 +/- 1.23 weeks) than in the steroid group (mean of 9.60 +/- 7.79 weeks). The facial nerve score after 1-3 weeks of treatment was significantly more severe (p < 0.001) in the steroid group compared to the methylcobalamin and methylcobalamin plus steroid groups. The improvement of concomitant symptoms was better in the methylcobalamin treated groups than the group treated with steroid alone.

Methods Find Exp Clin Pharmacol 1995 Oct;17(8):539-44

Enteral vitamin B12 supplements reverse postgastrectomy B12 deficiency

OBJECTIVE: To examine the development of chemical and clinical vitamin B12 deficiency after total gastrectomy, and to evaluate the efficacy of supplemental oral B12 administration. SUMMARY BACKGROUND DATA: Postgastrectomy anemia is due to deficiencies of iron and vitamin B12, and parenteral B12 administration is the only appropriate treatment. However, no guidelines exist for the prophylactic use of B12 in patients who undergo total gastrectomy, the clinical presentation of B12 deficiency in this context has not been defined, and the question of whether oral B12 administration can be used to prevent and treat B12 deficiency has not been examined. METHODS: Serum B12 concentrations were measured in 31 patients who had undergone total gastrectomy. Symptoms related to B12 deficiency were surveyed in detail. Serum B12 concentrations were measured every 6 months after total gastrectomy in 10 patients. Thirty one patients received supplemental B12: 18 patients orally and 13 by intramuscular injection. RESULTS: The B12 concentration dropped below the lower limit of normal (200 pg/mL) for the first time in two patients at 1 year, in four patients at 2 years, in three patients at 3 years, and in one patient at 4 years. Seventy-eight percent of patients reported some symptoms related to B12 deficiency. The serum B12 concentration in patients who received supplemental B12 orally increased rapidly and all symptoms resolved with oral therapy alone. CONCLUSIONS: B12 deficiency can develop as early as 1 year after total gastrectomy and causes symptoms. Because enteral B12 treatment increases the serum B12 concentration and leads to rapid resolution of symptoms, it should be prescribed routinely to patients.

Ann Surg 2000 Aug;232(2):199-201

Vitamin B12 deficiency in the elderly

Vitamin B12 deficiency is estimated to affect 10%-15% of people over the age of 60, and the laboratory diagnosis is usually based on low serum vitamin B12 levels or elevated serum methylmalonic acid and homocysteine levels. Although elderly people with low vitamin B12 status frequently lack the classical signs and symptoms of vitamin B12 deficiency, e.g. megaloblastic anemia, precise evaluation and treatment in this population is important. Absorption of crystalline vitamin B12 does not decline with advancing age. However, compared with the younger population, absorption of protein-bound vitamin B12 is decreased in the elderly, owing to a high prevalence of atrophic gastritis in this age group. Atrophic gastritis results in a low acid-pepsin secretion by the gastric mucosa, which in turn results in a reduced release of free vitamin B12 from food proteins. Furthermore, hypochlorhydria in atrophic gastritis results in bacterial overgrowth of the stomach and small intestine, and these bacteria may bind vitamin B12 for their own use. The ability to absorb crystalline vitamin B12 remains intact in older people with atrophic gastritis. The 1998 recommended daily allowance for vitamin B12 is 2.4 micrograms, but elderly people should try to obtain their vitamin B12 from either supplements or fortified foods (e.g. fortified ready-to-eat breakfast cereals) to ensure adequate absorption from the gastrointestinal tract. Because the American food supply is now being fortified with folic acid, concern is increasing about neurologic exacerbation in individuals with marginal vitamin B12 status and high-dose folate intake.

Annu Rev Nutr 1999;19:357-77

Effects of vitamin B12 on performance and circadian rhythm in normal subjects

This preliminary study investigates effects of methyl- and cyanocobalamin on circadian rhythms, well-being, alertness, and concentration in healthy subjects. Six women (mean age 35 years) and 14 men (mean age 37 years) were randomly assigned to treatment for 14 days with 3 mg cyano-(CB12) or methylcobalamin (MB12) after 9 days of pre-treatment observation. Levels in the CB12 group increased rapidly in the first, then slowly in the second treatment week, whereas increase in the MB12 group was linear. Urinary aMT6s excretion was reduced by both forms of vitamin B12 over 24 hours with a significant decrease between 0700-1100 hours, whereas urinary excretion of potassium was significantly increased between 0700-1100 hours. Activity from 2300-0700 hours increased significantly under both forms of vitamin B12. Sleep time was significantly reduced under MB12 intake. In this group the change in the visual analogue scales items "sleep quality," "concentration," and "feeling refreshed" between pretreatment and the first week of treatment showed significant correlations with vitamin B12 plasma levels. Cortisol excretion and temperature were not affected by either medication. We conclude that vitamin B12 exerts a direct influence on melatonin. Only MB12 has a positive psychotropic alerting effect with a distribution of the sleep-wake cycle toward sleep reduction.

Neuropsychopharmacology 1996 Nov;15(5):456-64

Subnormal serum vitamin B12 and behavioural and psychological symptoms in Alzheimer's disease

The objective of this study was to examine whether patients with Alzheimer's disease (AD) with subnormal vitamin B12 levels show more frequent behavioural and psychological symptoms of dementia (BPSD) than AD patients with normal vitamin B12 levels. The design was a prospective case-control study. The study took place at a memory-clinic of a department of geriatric medicine in a teaching hospital. There were seventy-three consecutive outpatients with probable AD, including 61 patients with normal and 12 patients with subnormal (<200 pg/ml) vitamin B12. BPSD were measured using the subscales disturbed behaviour and mood of the Nurses' Observation Scale for Geriatric Patients (NOSGER), the Cornell Scale for Depression and the four criteria for personality change in dementia from the International Classification of Diseases (ICD-10). Controlling for dementia duration and degree of severity of the cognitive deficits, there were significant inverse associations between vitamin B12 status and ICD-10 irritability (p=0.045) and NOSGER subscale disturbed behaviour (p=0.015). Low vitamin B12 serum levels are associated with BPSD in AD. Vitamin B12 could play a role in the pathogenesis of behavioural changes in AD.

Int J Geriatr Psychiatry 2000 May;15(5):415-8

Vitamin B12 levels are low in hospitalized psychiatric patients

BACKGROUND: Deficiency of vitamin B12, a key component in the catabolism of monoamines, is associated with various neuropsychiatric disorders and may be more frequent in hospitalized patients. METHOD: We reviewed vitamin B12 assays performed in a laboratory of a large Israeli psychiatric hospital over a 23-month period to examine prevalence of low values and compared vitamin B12 deficient patients to those with normal levels on various parameters. In addition, vitamin levels in a random sample of in-patients whose nutritional intake was determined, were examined. RESULTS: 20% of 644 vitamin B12 assays were in the low (200 pg/ml) and 10% in the deficient (< 160 pg/ml) range. 24 selected vitamin B12 deficient patients (70.8% with diagnosis of schizophrenia) did not differ from controls (N = 35) in age, sex ratio, hemoglobin concentration, MCV, diagnostic distribution or number and length of hospitalizations, but had slightly lower (but normal) mean folate levels. Rates of vitamin B12 deficiency in the patient sample, whose nutritional intake was adequate, did not differ significantly from those in the laboratory survey. CONCLUSION: Vitamin B12 deficiency is common in chronically ill psychotic patients with adequate nutrition and is not readily detected by routine hematology tests.

Isr J Psychiatry Relat Sci 2000;37(1):41-5

Ultra-high dose methylcobalamin promotes nerve regeneration in experimental acrylamide neuropathy

Despite intensive searches for therapeutic agents, few substances have been convincingly shown to enhance nerve regeneration in patients with peripheral neuropathies. Recent biochemical evidence suggests that an ultra-high dose of methylcobalamin (methyl-B12) may up-regulate gene transcription and thereby protein synthesis. We examined the effects of ultra-high dose of methyl-B12 on the rate of nerve regeneration in rats with acrylamide neuropathy, using the amplitudes of compound muscle action potentials (CMAPs) after tibial nerve stimulation as an index of the number of regenerating motor fibers. After intoxication with acrylamide, all the rats showed equally decreased CMAP amplitudes. The animals were then divided into 3 groups; rats treated with ultra-high (500 micrograms/kg body weight, intraperitoneally) and low (50 micrograms/kg) doses of methyl-B12, and saline-treated control rats. Those treated with ultra-high dose showed significantly faster CMAP recovery than saline-treated control rats, whereas the low-dose group showed no difference from the control. Morphometric analysis revealed a similar difference in fiber density between these groups. Ultra-high doses of methyl-B12 may be of clinical use for patients with peripheral neuropathies.

J Neurol Sci 1994 Apr;122(2):140-3

Helicobacter pylori-is it a novel causative agent in Vitamin B12 deficiency?

BACKGROUND: Evidence for vitamin B12 deficiency usually involves combinations of low serum vitamin B12 levels, clinical and metabolic abnormalities, and therapeutic response. Identification of the underlying cause is important in the diagnosis of vitamin B12 deficiency that is usually attributed to malabsorption. Helicobacter pylori is one of the most common causes of peptic ulcer disease worldwide and a major cause of chronic superficial gastritis leading to atrophy of gastric glands. It is suggested that there may be a casual relationship between H. pylori and food-cobalamin malabsorption. OBJECTIVES: To evaluate the H. pylori incidence in patients with vitamin B12 deficiency prospectively and to assess whether treatment for H pylori infection could correct this deficiency over time. PATIENTS AND METHODS: We performed a prospective cohort study involving 138 patients who had anemia and vitamin B12 deficiency. An upper gastrointestinal endoscopy was performed to assess the severity of atrophic gastritis and biopsy specimens for Campylobacter-like organisms tests and histological examination for H pylori were obtained at the time of diagnosis. The diagnosis of H. pylori prompted a combination treatment. RESULTS: Helicobacter pylori was detected in 77 (56%) of 138 patients with vitamin B12 deficiency and eradication of H pylori infection successfully improved anemia and serum vitamin B12 levels in 31 (40 %) of 77 infected patients. CONCLUSIONS: Helicobacter pylori seems to be a causative agent in the development of adult vitamin B12 deficiency. Eradication of H. pylori infection alone may correct vitamin B12 levels and improve anemia in this subgroup of patients.

Arch Intern Med 2000 May 8;160(9):1349-53

 


CLA

Activation of PPARgamma may mediate a portion of the anticancer activity of conjugated linoleic acid

A number of human cancer cell lines express the PPARgamma transcription factor, and agonists for PPARgamma are reported to promote apoptosis in these cell lines and impede their clonal expansion both in vitro and in vivo. Conjugated linoleic acid (CLA) can activate PPARgamma in rat adipocytes, possibly explaining CLA's antidiabetic effects in Zucker fatty rats. It is thus reasonable to suspect that a portion of CLA's broad spectrum anticarcinogenic activity is mediated by PPARgamma activation in susceptible tumors.

Copyright 2000 Harcourt Publishers Ltd. Med Hypotheses 2000 Sep;55(3):187-188

Conjugated linoleic acid suppresses triglyceride accumulation and induces apoptosis in 3T3-L1 preadipocytes

Four sets of experiments were conducted to examine the influence of conjugated linoleic acid (CLA) isomers during proliferation and differentiation of cultures of 3T3-L1 preadipocytes using physiological culturing conditions. Cultures treated with either albumin [bovine serum albumin (BSA) vehicle] or linoleic acid (LA) served as controls. For the proliferation study (Expt.1), cells were cultured in media containing a crude mixture of CLA isomers or pure LA at 0, 10, 50, or 200 microM for 4 d. Preadipocyte proliferation (cell number, 3H-thymidine incorporation into DNA) decreased as the level of CLA increased in the cultures. In contrast, LA had no impact on DNA synthesis. In Experiment 2a, postconfluent cultures were grown in media containing a crude mixture of CLA isomers or LA at 0, 10, 50, or 200 microM for the next 6 d. Postconfluent cultures supplemented with 50-200 microM CLA had less triglyceride (TG) and were smaller in size than cultures supplemented with similar amounts of LA. In Experiment 2b, postconfluent cultures supplemented with 200 microM of a crude mixture of CLA isomers or LA were harvested on days 1, 3, 6, or 9. Differences in TG content of cultures supplemented with 200 microM CLA compared to control and LA-supplemented cultures became apparent after 3 d of culture. Experiments 3a and 3b examined whether the fatty acid vehicle (BSA vs. ethanol) or the vitamin E status (+/-0.2 mM alpha-tocopherol) of the cultures altered CLA's impact on preadipocyte TG content. In Experiment 3a, ethanol-treated cultures had more TG than non-ethanol-treated cultures regardless of the fatty acid treatment. In Experiment 3b, cultures treated with 100 microM of either a crude mixture of CLA or the trans-10,cis-12 CLA isomer without supplemental vitamin E for 6 d had less TG than CLA-treated cultures containing vitamin E. In Experiment 4, postconfluent cultures were grown in media containing 100 microM LA or either a crude mixture of CLA isomers or the trans-10,cis-12 CLA isomer for 24-96 h to assess CLA's influence on the cell cycle and indices of apoptosis. Cultures treated with 100 microM CLA for 24-96 h had more apoptotic cells than BSA- or LA-treated cultures. Furthermore, cultures treated for 48 h with CLA had fewer cells in the S-phase than control cultures. The effects of the trans-10,cis-12 CLA isomer were more pronounced than those of the crude mixture of CLA isomers. These data suggest that CLA may exert its antiobesity effects by inhibiting proliferation, attenuating TG content, and/or inducing apoptosis in (pre)adipocytes.

Lipids 2000 Aug;35(8):899-910

Conjugated linoleic acid supplementation reduces adipose tissue by apoptosis and develops lipodystrophy in mice

Conjugated linoleic acid (CLA) is a naturally occurring group of dienoic derivatives of linoleic acid found in beef and dairy products. CLA has been reported to reduce body fat. To examine the mechanism(s) of CLA reduction of fat mass, female C57BL/6J mice were fed standard semipurified diets (10% fat of total energy) with or without CLA (1% wt/wt). Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick endlabeling (TUNEL) and DNA fragmentation analysis revealed that fat-mass decrease by CLA was mainly due to apoptosis. Tumor necrosis factor (TNF)-alpha and uncoupling protein (UCP)-2 mRNA levels increased 12- and 6-fold, respectively, in isolated adipocytes from CLA-fed mice compared with control mice. Because it is known that TNF-alpha induces apoptosis of adipocytes and upregulates UCP2 mRNA, a marked increase of TNF-alpha mRNA with an increase of UCP2 in adipocytes caused CLA-induced apoptosis. However, with a decrease of fat mass, CLA supplementation resulted in a state resembling lipoatrophic diabetes: ablation of brown adipose tissue, a marked reduction of white adipose tissue, marked hepatomegaly, and marked insulin resistance. CLA supplementation decreased blood leptin levels, but continuous leptin infusion reversed hyperinsulinemia, indicating that leptin depletion contributes to the development of insulin resistance. These results demonstrate that intake of CLA reduces adipose tissue by apoptosis and results in lipodystrophy, but hyperinsulinemia by CLA can be normalized by leptin administration.

Diabetes 2000 Sep;49(9):1534-42

The disease burden associated with overweightness and obesity

CONTEXT: Overweight and obesity are increasing dramatically in the United States and most likely contribute substantially to the burden of chronic health conditions. OBJECTIVE: To describe the relationship between weight status and prevalence of health conditions by severity of overweight and obesity in the US population. DESIGN AND SETTING: Nationally representative cross-sectional survey using data from the Third National Health and Nutrition Examination Survey (NHANES III), which was conducted in 2 phases from 1988 to 1994. PARTICIPANTS: A total of 16884 adults, 25 years and older, classified as overweight and obese (body mass index [BMI] > or =25 kg/m2) based on National Institutes of Health recommended guidelines. MAIN OUTCOME MEASURES: Prevalence of type 2 diabetes mellitus, gallbladder disease, coronary heart disease, high blood cholesterol level, high blood pressure, or osteoarthritis. RESULTS: Sixty-three percent of men and 55% of women had a body mass index of 25 kg/m2 or greater. A graded increase in the prevalence ratio (PR) was observed with increasing severity of overweight and obesity for all of the health outcomes except for coronary heart disease in men and high blood cholesterol level in both men and women. With normal-weight individuals as the reference, for individuals with BMIs of at least 40 kg/m2 and who were younger than 55 years, PRs were highest for type 2 diabetes for men (PR, 18.1; 95% confidence interval [CI], 6.7-46.8) and women (PR, 12.9; 95% CI, 5.7-28.1) and gallbladder disease for men (PR, 21.1; 95% CI, 4.1-84.2) and women (PR, 5.2; 95% CI, 2.9-8.9). Prevalence ratios generally were greater in younger than in older adults. The prevalence of having 2 or more health conditions increased with weight status category across all racial and ethnic subgroups. CONCLUSIONS: Based on these results, more than half of all US adults are considered overweight or obese. The prevalence of obesity-related comorbidities emphasizes the need for concerted efforts to prevent and treat obesity rather than just its associated comorbidities.

JAMA 1999 Oct 27;282(16):1523-9