The activities of coenzyme Q10 and vitamin B6 for immune responses

Effects of coenzyme Q10 supplementation on inflammation, angiogenesis, and oxidative stress in breast cancer patients: a systematic review and meta-analysis of randomized controlled- trials

BACKGROUND/OBJECTIVE

Systemic inflammation and oxidative stress (OS) are associated with breast cancer. CoQ10 as an adjuvant treatment with conventional anti-cancer chemotherapy has been demonstrated to help in the inflammatory process and OS. This systematic review and meta-analysis of randomized clinical trials (RCTs) aimed to evaluate the efficacy of CoQ10 supplementation on levels of inflammatory markers, OS parameters, and matrix metalloproteinases/tissue inhibitor of metalloproteinases (MMPs/TIMPs) in patients with breast cancer.

METHODS

A systematic literature search was carried out using electronic databases, including PubMed, Web of Science, Scopus, Google Scholar, and Embase, up to December 2020 to identify eligible RCTs evaluating the effect of CoQ10 supplementation on OS biomarkers, inflammatory cytokines, and MMPs/TIMPs. From 827 potential reports, 5 eligible studies consisting of 9 trials were finally included in the current meta-analysis. Quality assessment and heterogeneity tests of the selected trials were performed using the PRISMA checklist protocol and the I² statistic, respectively. Fixed and random-effects models were assessed based on the heterogeneity tests, and pooled data were determined as the standardized mean difference (SMD) with a 95% confidence interval (CI).

RESULTS

Our meta-analysis of the pooled findings for inflammatory biomarkers of OS and MMPs showed that CoQ10 supplementation (100 mg/day for 45-90 days) significantly decreased the levels of VEGF [SMD: - 1.88, 95% CI: (- 2. 62 to - 1.13); I² = 93.1%, p < 0.001], IL-8 [SMD: - 2.24, 95% CI: (- 2.68 to - 1.8); I² = 79.6%, p = 0.001], MMP-2 [SMD: - 1.49, 95% CI: (- 1.85 to - 1.14); I² = 76.3%, p = 0.005] and MMP-9 [SMD: - 1.58, 95% CI: (- 1.97 to - 1.19); I² = 79.6%, p = 0.002], but no significant difference was observed between CoQ10 supplementation and control group on TNF-α [SMD: - 2.30, 95% CI: (- 2.50 to - 2.11); I² = 21.8%, p = 0.280], IL-6 [SMD: - 1.56, 95% CI: (- 1.73 to - 1.39); I² = 0.0%, p = 0.683], IL-1β [SMD: - 3.34, 95% CI: (- 3.58 to - 3.11); I² = 0.0%, p = 0.561], catalase (CAT) [SMD: 1.40, 95% CI: (1.15 to 1.65); I² = 0.0%, p = 0.598], superoxide dismutase (SOD) [SMD: 2.42, 95% CI: (2.12 to 2.71); I² = 0.0%, p = 0.986], glutathione peroxidase (GPx) [SMD: 2.80, 95% CI: (2.49 to 3.11); I² = 0.0%, p = 0.543]], glutathione (GSH) [SMD: 4.71, 95% CI: (4.26 to 5.16); I² = 6.1%, p = 0.302] and thiobarbituric acid reactive substances (TBARS) [SMD: - 3.20, 95% CI: (- 3.53 to - 2.86); I² = 29.7%, p = 0.233].

CONCLUSION

Overall, the findings showed that CoQ10 supplementation reduced some of the important markers of inflammation and MMPs in patients with breast cancer. However, further studies with controlled trials for other types of cancer are needed to better understand and confirm the effect of CoQ10 on tumor therapy.

Coenzyme Q10 and Immune Function: An Overview

Coenzyme Q10 (CoQ10) has a number of important roles in the cell that are required for optimal functioning of the immune system. These include its essential role as an electron carrier in the mitochondrial respiratory chain, enabling the process of oxidative phosphorylation to occur with the concomitant production of ATP, together with its role as a potential lipid-soluble antioxidant, protecting the cell against free radical-induced oxidation. Furthermore, CoQ10 has also been reported to have an anti-inflammatory role via its ability to repress inflammatory gene expression. Recently, CoQ10 has also been reported to play an important function within the lysosome, an organelle central to the immune response. In view of the differing roles CoQ10 plays in the immune system, together with the reported ability of CoQ10 supplementation to improve the functioning of this system, the aim of this article is to review the current literature available on both the role of CoQ10 in human immune function and the effect of CoQ10 supplementation on this system.

Coenzyme Q10: Novel Formulations and Medical Trends

The aim of this review is to shed light over the most recent advances in Coenzyme Q10 (CoQ10) applications as well as to provide detailed information about the functions of this versatile molecule, which have proven to be of great interest in the medical field. Traditionally, CoQ10 clinical use was based on its antioxidant properties; however, a wide range of highly interesting alternative functions have recently been discovered. In this line, CoQ10 has shown pain-alleviating properties in fibromyalgia patients, a membrane-stabilizing function, immune system enhancing ability, or a fundamental role for insulin sensitivity, apart from potentially beneficial properties for familial hypercholesterolemia patients. In brief, it shows a remarkable amount of functions in addition to those yet to be discovered. Despite its multiple therapeutic applications, CoQ10 is not commonly prescribed as a drug because of its low oral bioavailability, which compromises its efficacy. Hence, several formulations have been developed to face such inconvenience. These were initially designed as lipid nanoparticles for CoQ10 encapsulation and distribution through biological membranes and eventually evolved towards chemical modifications of the molecule to decrease its hydrophobicity. Some of the most promising formulations will also be discussed in this review.

An integrated analysis of public genomic data unveils a possible functional mechanism of psoriasis risk via a long-range ERRFI1 enhancer

BACKGROUND

Psoriasis is a chronic inflammatory skin disease, for which genome-wide association studies (GWAS) have identified many genetic variants as risk markers. However, the details of underlying molecular mechanisms, especially which variants are functional, are poorly understood.

METHODS

We utilized a computational approach to survey psoriasis-associated functional variants that might affect protein functions or gene expression levels. We developed a pipeline by integrating publicly available datasets provided by GWAS Catalog, FANTOM5, GTEx, SNP2TFBS, and DeepBlue. To identify functional variants on exons or splice sites, we used a web-based annotation tool in the Ensembl database. To search for noncoding functional variants within promoters or enhancers, we used eQTL data calculated by GTEx. The data of variants lying on transcription factor binding sites provided by SNP2TFBS were used to predict detailed functions of the variants.

RESULTS

We discovered 22 functional variant candidates, of which 8 were in noncoding regions. We focused on the enhancer variant rs72635708 (T > C) in the 1p36.23 region; this variant is within the enhancer region of the ERRFI1 gene, which regulates lipid metabolism in the liver and skin morphogenesis via EGF signaling. Further analysis showed that the ERRFI1 promoter spatially contacts with the enhancer, despite the 170 kb distance between them. We found that this variant lies on the AP-1 complex binding motif and may modulate binding levels.

CONCLUSIONS

The minor allele rs72635708 (rs72635708-C) might affect the ERRFI1 promoter activity, which results in unstable expression of ERRFI1, enhancing the risk of psoriasis via disruption of lipid metabolism and skin cell proliferation. Our study represents a successful example of predicting molecular pathogenesis by integration and reanalysis of public data.

Dietary vitamin B intake and the risk of esophageal cancer: a meta-analysis

BACKGROUND

Several epidemiology studies have explored the association between dietary B vitamins' intake and the risk of esophageal cancer (EC). However, the results remain inconclusive. Thus, we conducted a systematic review with meta-analysis to evaluate such association.

METHODS

Literature retrieval was performed using PubMed (Medline), ScienceDirect, and Cochrane Library electronic databases for all studies published from database inception to December 2017.

RESULTS

The meta-analysis included 19 studies and showed an overall decreased risk of EC (OR=0.77, 95% CI: 0.68-0.87) in association with multivitamin B (ie, B1, B2, B3, B5, B6, B9, and B12) dietary intake. In a subgroup analysis based on vitamin B subclass, B1, B3, B6, and B9 vitamins were associated with decreased EC risk (vitamin B1: OR=0.68, 95% CI: 0.56-0.82; vitamin B3: OR=0.70, 95% CI: 0.53-0.94; vitamin B6: OR=0.64, 95% CI: 0.49-0.83; and vitamin B9: OR=0.69, 95% CI: 0.55-0.86). By contrast, no association was detected between dietary vitamin B2 and vitamin B5 intake and EC risk (vitamin B2: OR=0.86, 95% CI: 0.64-1.16; vitamin B5: OR=0.49, 95% CI: 0.20-1.20), whereas a potential non-linear dose-response association was found between dietary vitamin B12 intake and EC risk. A statistically significant, inverse association was observed for an increase of 100 µg/day in supplemental vitamin B6 and B9 and EC risk (vitamin B6: OR=0.98, 95% CI: 0.98-0.99; vitamin B9: OR= 0.89; 95% CI: 0.86-0.94).

CONCLUSION

These findings support that vitamin B may have an influence on carcinogenesis of the esophagus. Vitamin B1, B3, B6, B9 showed a decreased risk of EC, and vitamin B12 showed an increased risk of EC.

Coenzyme Q10: A Review

Coenzyme Q10 (CoQ10) is a provitamin manufactured by the body. It functions as a coenzyme for mitochondrial enzymes. It has been shown to be deficient in patients with cardiovascular disease, cancer, Acquired Immune Deficiency Syndrome (AIDS), muscular dystrophy, spontaneous abortion, male infertility, and periodontal disease. Studies of CoQ10 show preliminary efficacy in the treatment of cardiovascular disease, but there is not enough evidence to date to support its benefit in cancer, AIDS, muscular dystrophy, spontaneous abortion, male infertility and periodontal disease treatments. Additional research is needed to evaluate its benefits in the treatment of these other conditions.

Feeding pyridoxine prevents Saprolegnia parasitica infection in fish Labeo rohita

A 60-day experiment was carried out to delineate the role of dietary pyridoxine (DP) in Labeo rohita fingerlings in modulating immunity and prevention of fungal infection. Two hundred and seventy fingerlings were randomly distributed into three treatments in triplicates. Three iso-caloric and iso-nitrogenous purified diets were prepared with graded levels of pyridoxine. Three experimental groups were C (0.0% DP), T1 (0.01% DP) and T2 (0.02% DP). The role of dietary pyridoxine in modulating immunity and prevention of fungal infection was assessed by haemato-immunological parameters like erythrocyte counts (EC), leucocyte counts (LC), haemoglobulin (Hb), packed cell volume (PCV), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), nitro-blue tetrazolium (NBT), phagocytic activity, albumin, globulin, total plasma protein, albumin/globulin and by challenge study with Saprolegnia parasitica, where relative percentage survival (RPS) were recorded. Hb, PCV, MCV, MCH, NBT, total plasma protein, albumin, globulin contents, lysozyme and phagocytic activity was significantly (P < 0.05) higher in DP fed group. Significantly (P < 0.05) higher RPS was recorded from T2 group fed with 0.02% DP for 45 days. Hence, DP has the capacity to stimulate nonspecific immunity and increase resistance to S. parasitica infection in L. rohita fingerlings.

Effect of rosuvastatin on plasma coenzyme Q10 in HIV-infected individuals on antiretroviral therapy

BACKGROUND

Coenzyme Q10 (CoQ10) deficiency has been associated with statin-induced myopathy, and supplementation with CoQ10 may reduce inflammation markers. The effects of statins on CoQ10 and its anti-inflammatory properties have not been investigated in HIV-positive patients.

OBJECTIVE

The objectives of this study were to examine the effect of rosuvastatin on CoQ10 and CoQ10/LDL ratio over 24-week SATURN-HIV trial, explore the associations between CoQ10 levels and markers of vascular disease, inflammation, and immune activation, and assess whether changes in CoQ10 affected the anti-inflammatory effects of statin therapy or were associated with myalgia symptoms.

METHODS

This was a secondary analysis of the SATURN-HIV trial, a 96-week randomized clinical trial of 10 mg daily rosuvastatin vs. placebo in HIV-infected patients on antiretroviral therapy. We assessed the statin treatment effect on CoQ10 levels and CoQ10/LDL ratios and whether changes in these markers were related to myalgias. Relationships between CoQ10, subclinical vascular disease, and biomarkers of inflammation and immune activation were explored using Spearman correlations and multivariable regression models.

RESULTS

Overall, 147 patients were included. Median age was 46 years; 78% were male and 68% African American. At baseline, CoQ10 levels and CoQ10/LDL ratio were modestly correlated with markers of HIV disease, immune activation, and carotid distensibility. After 24 weeks of statin therapy, CoQ10 levels decreased (p = 0.002 for between group difference) and CoQ10/LDL ratio increased (p = 0.036). In the statin treatment arm, we did not find evidence of a relationship between changes in CoQ10 or CoQ10/LDL ration and changes in markers of inflammation or immune activation. There was a borderline statistically significant association between changes in CoQ10 and myalgia symptoms [OR 4.0 per 0.1 mg/L decrease in CoQ10, p = 0.07].

CONCLUSION

Twenty-four weeks of 10 mg daily rosuvastatin decreases CoQ10 concentration and increases CoQ10/LDL ratio in HIV-infected patients on antiretroviral therapy.

Effect of Coenzyme Q10 on Th1/Th2 Paradigm in Females with Idiopathic Recurrent Pregnancy Loss

PROBLEM

Recurrent pregnancy loss is characterized by predominant Th1-type immunity and increased reactive oxygen species. Low levels of Coenzyme Q10 are found in the plasma of RPL as compared to healthy pregnant females. Our aim was to investigate whether in vitro supplementation of PBMCs from such females with CoQ10 could change the observed Th1 bias.

METHOD OF STUDY

PBMCs were isolated from 20 RPL pregnant and non-pregnant females and 16 healthy pregnant females and incubated with CoQ10 in in vitro conditions. Phenotyping of Th1, Th2, and Th17 cells was performed by flow cytometry. Cytokine levels were determined by ELISA.

RESULTS

PBMCs treated with CoQ10 showed significantly decreased percentage of Th1 cells (P < 0.005) in pregnant females with history of RPL than in the untreated ones. Also, levels of IFN-γ and TNF-α were significantly decreased in the culture supernatant of treated PBMCs from RPL. DCFDA staining showed significantly reduced production of ROS in the treated PBMCs in RPL females.

CONCLUSION

CoQ10 was effective in maintaining the immune homeostasis by reducing the proportion of IFN-γ-producing T cells and proinflammatory cytokine levels in the RPL pregnant females. This property could be attributed to the capability of CoQ10 in reducing oxidative stress by decreasing ROS production.

Coenzyme Q10 and immunity: A case report and new implications for treatment of recurrent infections in metabolic diseases

Coenzyme Q10 (CoQ10) deficiency can manifest diversely, from isolated myopathy to multisystem involvement. Immune dysregulation has not been reported as a feature of the disease. We report a four-year old girl with failure to thrive, recurrent infections, developmental delay with hypotonia, and CoQ10 deficiency with impaired immune function, which improved after CoQ10 and immunoglobulin replacement therapy. Immune dysfunction in CoQ10 deficiency should be considered and treated appropriately.

Development and characterization of phospholipid-stabilized submicron aqueous dispersions of coenzyme Q₁₀ presenting continuous vibrating-mesh nebulization performance

Coenzyme Q₁₀ (CoQ₁₀) is a poorly-water soluble compound that is being investigated for the treatment of carcinomas. The aim of this research was to develop a suitable formulation for pulmonary delivery of this anticancer agent. An appropriate selection of excipients (phospholipids) and a suitable device (Aeroneb Pro® vibrating-mesh nebulizer) were selected initially after reviewing the literature. After characterization of the bulk drug, a feasible manufacturing process was selected to obtain small particle size dispersions of CoQ₁₀. Following selection of an appropriate process, the parameters affecting drug particle size were studied. Using LD and gravimetrical analysis, nebulization was evaluated to assess the performance of the inhalation system triad: drug-excipients-device. CoQ₁₀ powder studied was crystalline with a melting point approximately at 51 °C and with a particle size of 30 µm. Microfluidization was found to be a suitable method to prepare submicron drug particles in aqueous dispersions. Increasing microfluidization processing to more than 50 passes did not provide further particle downsizing for both soya phosphatidylcholine (lecithin) and dipalmitoyl phosphatidylcholine (DPPC) dispersions of CoQ₁₀, presenting Z-average values of approximately 130 and 70 nm, respectively. Nebulization performance of lecithin-stabilized CoQ₁₀ dispersions varied according to number of passes in the microfluidizer. Formulations processed with 10 passes presented steadier nebulization over time and different rheological behavior compared to those processed with 30 or 50 passes. In conclusion, aqueous dispersions of CoQ₁₀ were adequately produced using a microfluidizer with characteristics that were suitable for pulmonary delivery with an Aeroneb Pro® nebulizer. Furthermore, the rheology of these dispersions appeared to play a significant role in the aerosol generation from the active vibrating-mesh nebulizer used.

Effects of vitamin B6 metabolism on oncogenesis, tumor progression and therapeutic responses

Pyridoxal-5'-phosphate (PLP), the bioactive form of vitamin B6, reportedly functions as a prosthetic group for >4% of classified enzymatic activities of the cell. It is therefore not surprising that alterations of vitamin B6 metabolism have been associated with multiple human diseases. As a striking example, mutations in the gene coding for antiquitin, an evolutionary old aldehyde dehydrogenase, result in pyridoxine-dependent seizures, owing to the accumulation of a metabolic intermediate that inactivates PLP. In addition, PLP is required for the catabolism of homocysteine by transsulfuration. Hence, reduced circulating levels of B6 vitamers (including PLP as well as its major precursor pyridoxine) are frequently paralleled by hyperhomocysteinemia, a condition that has been associated with an increased risk for multiple cardiovascular diseases. During the past 30 years, an intense wave of clinical investigation has attempted to dissect the putative links between vitamin B6 and cancer. Thus, high circulating levels of vitamin B6, as such or as they reflected reduced amounts of circulating homocysteine, have been associated with improved disease outcome in patients bearing a wide range of hematological and solid neoplasms. More recently, the proficiency of vitamin B6 metabolism has been shown to modulate the adaptive response of tumor cells to a plethora of physical and chemical stress conditions. Moreover, elevated levels of pyridoxal kinase (PDXK), the enzyme that converts pyridoxine and other vitamin B6 precursors into PLP, have been shown to constitute a good, therapy-independent prognostic marker in patients affected by non-small cell lung carcinoma (NSCLC). Here, we will discuss the clinical relevance of vitamin B6 metabolism as a prognostic factor in cancer patients.

Plasma coenzyme Q10 levels and postmenopausal breast cancer risk: the multiethnic cohort study

BACKGROUND

Coenzyme Q10 (CoQ10) is a component of the mitochondrial electron transport chain and is considered an important cellular antioxidant. Decreased circulating CoQ10 levels have been reported in women with breast cancer, but evidence is limited. We examined the association of plasma CoQ10 levels with postmenopausal breast cancer risk using prospectively collected blood samples.

METHODS

Prediagnostic plasma levels of total CoQ10 were measured among 160 incident postmenopausal breast cancer cases and 289 controls in the Multiethnic Cohort Study. Cases and controls were individually matched on age, sex, ethnicity, study location (Hawaii or California), hormone replacement therapy use, date and time of specimen collection, and hours of fasting. Logistic regression was used to compute odds ratios and 95% confidence intervals.

RESULTS

Plasma CoQ10 levels were positively associated with breast cancer risk, overall (P = 0.04). The association was stronger after women diagnosed within 1 year of blood draw were excluded to eliminate possible preclinical cases (odds ratio for the highest versus the lowest tertile, 2.26; 95% confidence interval, 1.22-4.19; P for trend = 0.01).

CONCLUSIONS

Higher CoQ10 levels in postmenopausal women may be associated with increased breast cancer risk.

IMPACT

A potential role for CoQ10 in the development and progression of breast cancer has been postulated, but epidemiologic evidence is lacking. Findings from this prospective cohort study add to the limited literature, indicating the potential positive association of circulating CoQ10 with postmenopausal breast cancer risk.

Consumption of pasteurized human lysozyme transgenic goats' milk alters serum metabolite profile in young pigs

Nutrition, bacterial composition of the gastrointestinal tract, and general health status can all influence the metabolic profile of an organism. We previously demonstrated that feeding pasteurized transgenic goats' milk expressing human lysozyme (hLZ) can positively impact intestinal morphology and modulate intestinal microbiota composition in young pigs. The objective of this study was to further examine the effect of consuming hLZ-containing milk on young pigs by profiling serum metabolites. Pigs were placed into two groups and fed a diet of solid food and either control (non-transgenic) goats' milk or milk from hLZ-transgenic goats for 6 weeks. Serum samples were collected at the end of the feeding period and global metabolite profiling was performed. For a total of 225 metabolites (160 known, 65 unknown) semi-quantitative data was obtained. Levels of 18 known and 4 unknown metabolites differed significantly between the two groups with the direction of change in 13 of the 18 known metabolites being almost entirely congruent with improved health status, particularly in terms of the gastrointestinal tract health and immune response, with the effects of the other five being neutral or unknown. These results further support our hypothesis that consumption of hLZ-containing milk is beneficial to health.

Recent developments in the treatment of atherosclerosis

Atherosclerosis is one of the most frequent causes of cardiac arrest. The major cause of this disease is high concentrations of lipid in the blood. Medicinal agents so far have been quite successful in the management of hyperlipidemia. Among the several widely used drugs, (fibrates, statins and niacin) statins are the most frequently prescribed in many forms of hyperlipidemia. Recently, statins have been found to produce serious toxicities, which are rare but can be potentially harmful and are noise concern for the immediate need to develop some new chemical entities in this category. This review is primarily concerned with recent developments in atherosclerotic drug discovery including novel inhibitors of cholesterol biosynthesis, cholesterol absorption inhibitors and antioxidants. The review also focuses on possible future targets including gene therapy.

Archaeosomes as Self-adjuvanting Delivery Systems for Cancer Vaccines*

Archaeal ether glycerolipid vesicles (archaeosomes) efficiently deliver exogenous antigen for induction of humoral and cell-mediated immunity. Because induction of CD8 cytotoxic T cells is critical for protective vaccination against tumors, we compared the ability of various archaeosome lipid compositions to evoke a strong CD8 CTL response to entrapped antigen. Subcutaneous immunization of mice with ovalbumin (OVA) entrapped in all archaeosome lipid compositions evoked a primary (day 10) splenic CTL response indicating processing for MHC class I presentation. Interestingly, several polar lipid compositions from halophilic archaea were very potent to adjuvant this early CTL response. Despite this, the lytic units reduced substantially by weeks 6-7. More importantly, at >50 weeks, only Methanobrevibacter smithii and Thermoplasma acidophilum both rich in bipolar membrane-spanning caldarchaeols, demonstrated recall memory CTLs. Immunization of mice with OVA entrapped in M. smithii, Halobacterium salinarum or T. acidophilum vesicles provided prophylactic protection against challenge with OVA-expressing solid tumors at 6 weeks. Even a dose of 3 microg OVA in archaeosomes significantly delayed tumor growth. Tumor protection was also noted in a therapeutic design wherein OVA-archaeosomes were injected concurrent with the tumor challenge. Interestingly, antigen-free T. acidophilum but not antigen-free H. salinarum archaeosomes provided innate therapeutic protection. Vaccination with a CTL peptide epitope from the melanoma differentiation antigen, tyrosinase-related protein 2, in archaeosomes induced a protective CD8 response against B16OVA metastasis, indicating potential for targeting self, tumor antigens. Thus, lipid structural properties of archaea may differentially modulate primary, long-term and/or innate immunity, impacting adjuvant choice for vaccine design.

Plasma pyridoxal 5'-phosphate and high-sensitivity C-reactive protein are independently associated with an increased risk of coronary artery disease

OBJECTIVE

Whether vitamin B6 exerts an independent or a synergic effect in combination with inflammation for the risk of coronary artery disease (CAD) is unclear. The purpose of this study was to investigate whether plasma pyridoxal 5'-phosphate (PLP) is dependent on or independent of the inflammation marker C-reactive protein (CRP) to associate with the risk of CAD.

METHODS

This was a hospital-based case-control. Patients were identified with cardiac catheterization as having at least 70% stenosis of one major coronary artery were assigned to the case group (n = 184). The control group (n = 516) was comprised of healthy individuals with normal blood biochemical values. All subjects' height, weight, blood pressure, plasma PLP, homocysteine, high-sensitivity CRP (hs-CRP), and lipid profiles were measured.

RESULTS

Plasma PLP concentration was only negatively associated with hs-CRP level in the control group (beta = -0.001, P = 0.03) but not in the CAD or pooled groups. The magnitude of the risk of CAD for low plasma PLP (odds ratio [OR] 2.39) and high hs-CRP (OR 3.37) was very similar. Low plasma PLP concentration combined with low hs-CRP level (OR 2.34) and high plasma PLP concentration combined with high hs-CRP level (OR 3.61) were independently associated with risk for CAD. However, the combined presence of low PLP and higher hs-CRP levels enhanced the risk of CAD and the magnitude was substantially greater (OR 4.35).

CONCLUSION

Plasma PLP and hs-CRP are independently associated with an increased risk of CAD, the combined presence of low PLP and high hs-CRP enhanced the risk of CAD, and the magnitude was almost double.

Archaeosome adjuvants: immunological capabilities and mechanism(s) of action

Archaeosomes (liposomes comprised of glycerolipids of Archaea) constitute potent adjuvants for the induction of Th1, Th2 and CD8(+) T cell responses to the entrapped soluble antigen. Archaeal lipids are uniquely constituted of ether-linked isoprenoid phytanyl cores conferring stability to the membranes. Additionally, varied head groups displayed on the glycerol-lipid cores facilitate unique immunostimulating interactions with mammalian antigen-presenting cells (APCs). The polar lipid from the archaeon, Methanobrevibacter smithii has been well characterized for its adjuvant potential, and is abundant in archaetidyl serine, promoting interaction with a phosphatidylserine receptor on APCs. These archaeosomes mediate MHC class I cross-priming via the phagosome-to-cytosol TAP-dependent classical processing pathway, and also upregulate costimulation by APCs without overt inflammatory cytokine production. Furthermore, they facilitate potent CD8(+) T cell memory to co-delivered antigen, comparable in magnitude and quality to live bacterial vaccine vectors. Archaeosome vaccines provide profound protection in murine models of infection and cancer. This technology is being developed for clinical application and offers a novel prospect for rational design and development of safe and potent subunit vaccines capable of eliciting T cell immunity against intracellular infections and cancers.

Effects of dietary L-carnitine and coenzyme Q10at different supplemental ages on growth performance and some immune response in ascites-susceptible broilers

Effects of dietary L-carnitine and coenzyme Q10 (CoQ10) at different supplemental ages on performance and some immune response were investigated in ascites-susceptible broilers. A 3 x 2 x 2 factorial design was used consisting of L-carnitine supplementation (0, 75, and 100 mg/kg), CoQ10 supplementation (0 and 40 mg/kg) and different supplemental ages (from day 1 on and from day 10 on). A total of 480 one-day-old Arbor Acre male broiler chicks were randomly allocated to 12 groups, every group had five replicates, each with eight birds. The birds were fed a corn-soybean based diet for six weeks. From day 10-21, all the birds were exposed to a low ambient temperature (12-15 degrees C) to increase the susceptibility to ascites. No significant effects were observed on growth performance by L-carnitine, CoQ10 supplementation, and different supplemental ages. Packed cell volume was significantly decreased by L-carnitine supplementation alone, and ascites heart index and ascites mortality were decreased by L-carnitine, CoQ10 supplementation alone, and L-carnitine + CoQ10 supplementation together (p < 0.05). Heart index of broilers was significantly improved by L-carnitine, CoQ10 supplementation alone during 0-3 week. Serum IgG content was improved by L-carnitine supplementation alone (p < 0.05), but lysozyme activity was increased by L-carnitine + CoQ10 supplementation together (p < 0.05). A significant L-carnitine by supplemental age interaction was observed in lysozyme activity. L-carnitine supplementation alone had no effects on the peripheral blood lymphocyte (PBL) proliferation in response to concanavalin A (ConA) and lipopolysaccharide, but supplemental CoQ10 alone and L-carnitine+ CoQ10 together decreased the PBL proliferation in response to ConA (p < 0.05). The present study suggested that L-carnitine + CoQ10 supplementation together had positive effects on some immune response of ascites-susceptible broilers, which might benefit for the reduction of broilers' susceptibility to ascites.

Dietary intake of vitamin B6 and concentration of vitamin B6 in blood samples of German vegans

OBJECTIVE

The study aimed to evaluate the dietary vitamin B6 intake and determine the vitamin B6 concentration in blood samples of German vegans.

DESIGN AND SETTING

Cross-sectional study with 33 examination sites all over Germany. Subjects Ninety-three vegans (50 females) with a mean (+/- standard deviation (SD)) age of 43.7 +/- 15.7 years who took no vitamin supplements.

METHODS

Dietary intake was assed using a semi-quantitative food-frequency questionnaire. Erythrocyte aspartate aminotransferase activity coefficient (EAST-AC) was calculated as the ratio of stimulated (pyridoxal 5'-phosphate added) to unstimulated activity in blood samples that were provided after an overnight fast.

RESULTS

Mean +/- SD vitamin B6 intake was 2.83 +/- 0.98 mg day(-1) and mean +/- SD protein intake was 56.6 +/- 21.7 g day(-1). Of the participants 4% showed vitamin B6 intakes lower than daily recommended intakes for Germany, 16% showed EAST-AC > 1.85, and a further 58% showed EAST-AC of 1.5-1-85. Moderate vegans were affected to a lesser extent than strict vegans. None of the established confounders was a significant predictor of EAST-AC. In logistic regression analyses the contribution of nutriments and cereals to pyridoxine intake was the only predictor of EAST-AC classified as < or = 1.85 and > 1.85, respectively.

CONCLUSIONS

In spite of the high total intake of vitamin B6, an adequate concentration in blood samples could not be realised for a majority of the participants. Due to the health implications of a marginal pyridoxine status, vegans should be encouraged to include foods with a high bioavailability of pyridoxine, such as beans, lentils and bananas, in the daily diet.

Risk assessment for coenzyme Q10 (Ubiquinone)

Coenzyme Q10 (CoQ10) widely occurs in organisms and tissues, and is produced and used as both a drug and dietary supplement. Increasing evidence of health benefits of orally administered CoQ10 are leading to daily consumption in larger amounts, and this increase justifies research and risk assessment to evaluate the safety. A large number of clinical trials have been conducted using a range of CoQ10 doses. Reports of nausea and other adverse gastrointestinal effects of CoQ10 cannot be causally related to the active ingredient because there is no dose-response relationship: the adverse effects are no more common at daily intakes of 1200 mg than at a 60 mg. Systematic evaluation of the research designs and data do not provide a basis for risk assessment and the usual safe upper level of intake (UL) derived from it unless the newer methods described as the observed safe level (OSL) or highest observed intake (HOI) are utilized. The OSL risk assessment method indicates that the evidence of safety is strong at intakes up to 1200 mg/day, and this level is identified as the OSL. Much higher levels have been tested without adverse effects and may be safe, but the data for intakes above 1200 mg/day are not sufficient for a confident conclusion of safety.

Vitamin B6 supplementation increases immune responses in critically ill patients

OBJECTIVE

To investigate whether vitamin B6 supplementation has a beneficial effect on immune responses in critically ill patients.

DESIGN

A single-blind intervention study.

SETTING

The study was performed at the Taichung Veterans General Hospital, the central part of Taiwan.

SUBJECTS

Fifty-one subjects who stayed over 14 days in the intensive care unit completed the study. Subjects were not treated with any vitamin supplement before the intervention.

INTERVENTIONS

Patients were randomly assigned to one of three groups, control (n = 20), a daily injection of 50 mg vitamin B-6 (B6 -50, n=15), or 100 mg vitamin B-6 (B6 -100, n = 16) for 14 days.

MAIN OUTCOME MEASURES

Plasma pyridoxal 5'-phosphate (PLP), pyridoxal (PL), 4-pyridoxic acid (4-PA), erythrocyte alanine (EALT-AC) and aspartate (EAST-AC) aminotransaminase activity coefficient, and urinary 4-PA were measured. The levels of serum albumin, hemoglobin, hematocrit, high-sensitivity C-reactive protein (hs-CRP) and immune responses (white blood cell, neutrophils, total lymphocytes count (TLC), T- (CD3) and B-(CD19) lymphocytes, T-helper (CD4) and suppressor (CD8) cells) were determined.

RESULTS

Plasma PLP, PL, 4-PA and urinary 4-PA concentrations significantly increased in two treated groups. T-lymphocyte and T-helper cell numbers and the percentage of T-suppressor cell significantly increased on day 14 in the B6 -50 group. Total lymphocyte count, T-helper and T-suppressor cell numbers, the percentage of T-lymphocyte cells and T-suppressors significantly increased in the B6 -100 group at the 14th day. There were no significant changes with respect to immune responses in the control group over 14 days.

CONCLUSIONS

A large dose of vitamin B6 supplementation (50 or 100 mg/day) could compensate for the lack of responsiveness of plasma PLP to vitamin B6 intake, and further increase immune response of critically ill patients.

SPONSORSHIP

This study was supported by the National Science Council, Taiwan, Republic of China (NSC-92-2320-B-040-026).

Effects of dietary pyridoxine on immune responses in abalone, Haliotis discus hannai Ino

A feeding experiment was conducted to investigate the effects of dietary pyridoxine (PN) on the immune responses of abalone, Haliotis discus hannai Ino. Purified diets supplemented with 0, 40, 800 mg PN kg(-1) or 80 mg kg(-1) of 4-deoxypyridoxine (PN antagonist) were fed to adult abalone (initial weight 45.77 +/- 0.25 g; initial shell length 68.02 +/- 0.78 mm) for 90 days. The air-dried brown kelp, Laminaria japonica, was used as a control diet. Each diet was fed to three replicate groups of abalone in a recirculation system using a completely randomised design. The results showed that weight gain ratio (WGR) of the abalone generally increased with the level of dietary PN supplementation though no significant differences were found among the treatments (P > 0.05). Phagocytic and phenoloxidase activities were significantly higher in abalone fed diets supplemented with 800 mg PN kg(-1) than those fed the PN-free diet or the one with 4-deoxypyridoxine (P < 0.05). Agglutination titre and respiratory burst activity were significantly higher in abalone fed diets supplemented with 40 mg PN kg(-1) than those fed the PN-free diet or the one with 4-deoxypyridoxine (P < 0.05). There were no significant differences in immunological characteristics between the abalone fed the diet containing 40 mg PN kg(-1) and those fed the diet containing 800 mg PN kg(-1) (P > 0.05). L. japonica resulted in significantly lower agglutination titre, respiratory burst and phagocytic activities than the artificial diets supplemented with 40 or 800 mg PN kg(-1) (P < 0.05). Total haemocyte count (THC), serum protein concentration, and the activities of lysozyme and acid phosphatase were not significantly affected by the dietary treatments (P > 0.05). These results demonstrate that dietary deficiency of pyridoxine suppresses the immune functions in H. discus hannai, and further investigations are needed to optimise the dietary level of this vitamin for maintaining the best immune responses in abalone.

Plasma pyridoxal 5′-phosphate is a significant indicator of immune responses in the mechanically ventilated critically ill

OBJECTIVES

This study assessed the effect of vitamin B6 status on immune responses in mechanically ventilated, critically ill patients and compared the results with those of healthy controls.

METHODS

This was designed as a cross-sectional observational study. Forty patients in the intensive care unit successfully completed this study. Vitamin B6 intake was recorded for 8 d. Severity of illness (Second Acute Physiology and Chronic Health Evaluation score) was recorded. Thirty-eighty healthy controls were recruited from the physical check unit of Taichung Veterans General Hospital (Taichung, Taiwan). All control subjects were given instruction on how to complete a 24-d diet recall. Vitamin B6 status was assessed by direct measures (plasma pyridoxal 5'-phosphate [PLP] and 4-pyridoxic acid) and indirect measures (erythrocyte alanine and aspartate aminotransferase activity coefficients). Levels of serum albumin, hemoglobin, hematocrit, high-sensitivity C-reactive protein, and immune responses (white blood cell, neutrophil, total lymphocytes, T lymphocytes [CD3], B lymphocytes [CD19], T-helper cells [CD4], and suppressor cells [CD8]) were determined.

RESULTS

Critically ill patients had sufficient vitamin B6 intake but showed marginal PLP deficiency (20.9 +/- 1.5 nmol/L). In addition, critically ill patients had significantly lower and abnormal immune responses than did healthy controls. There was no significant correlation of vitamin B6 intake and erythrocyte alanine and aspartate aminotransaminase activity coefficients with immune indices. Plasma PLP concentration was strongly negatively correlated with high-sensitivity C-reactive protein level. However, plasma PLP was significantly associated with immune responses after adjustment for age, sex, high-sensitivity C-reactive protein, and the other four vitamin B6 indicators.

CONCLUSIONS

Plasma PLP is a significant indicator of immune responses in human subjects. Further research is warranted to study whether vitamin B6 supplementation in critically ill patients improves their immune responses.

Efficacy of Coenzyme Q10 for Improved Tolerability of Cancer Treatments: A Systematic Review

Purpose

The aim of this systematic review was to summarize and evaluate the evidence available for oral supplementation with coenzyme Q10 (CoQ10) to improve the tolerability of cancer treatments.

Materials and Methods

Searches for all published and unpublished controlled trials were carried out on seven databases. Manufacturers of CoQ10 were identified and contacted. Controlled clinical trials of monopreparations of CoQ10 administered orally to cancer patients were included. No language restrictions were imposed. Data were extracted independently by two authors according to predefined criteria.

Results

Six studies were included in the review, including three randomized clinical trials and three nonrandomized clinical trials. Patients in five of six studies received anthracyclines. The results suggested that CoQ10 provides some protection against cardiotoxicity or liver toxicity during cancer treatment. However, because of inadequate reporting and analysis, as well as questionable validity of outcome measures, the results are not conclusive.

Conclusion

Suggestions that CoQ10 might reduce the toxicity of cancer treatments have not been tested by rigorous trials. Further investigations are necessary to determine whether CoQ10 can improve the tolerability of cancer treatments.

Assessing websites on complementary and alternative medicine for cancer

BACKGROUND

Many cancer patients search the World Wide Web for information on complementary and alternative medicine. The aim of this study was to evaluate the quality of such information and identify the treatments most frequently discussed. Materials and methods We used a pre-tested search strategy to identify the websites that are most likely to be used by cancer patients and assessed them according to pre-defined criteria.

RESULTS

Thirty-two websites were included in this analysis. The quality of these sites was scored on a point system and varied between 8 and 14 points with a maximum of 14. Most sites issued recommendations for a plethora of treatments, which are typically not supported by sound scientific evidence. Three sites had the potential for harming patients through the advice issued. The most frequently discussed therapies were herbal medicines, diets and mind-body therapies.

CONCLUSION

The most popular websites on complementary and alternative medicine for cancer offer information of extremely variable quality. Many endorse unproven therapies and some are outright dangerous.

Breakfast cereal fortified with folic acid, vitamin B-6, and vitamin B-12 increases vitamin concentrations and reduces homocysteine concentrations: a randomized trial

BACKGROUND

High homocysteine and low B vitamin concentrations have been linked to the risk of vascular disease, stroke, and dementia and are relatively common in older adults.

OBJECTIVE

We assessed the effect of breakfast cereal fortified with folic acid, vitamin B-6, and vitamin B-12 on vitamin and homocysteine status.

DESIGN

A randomized, double-blind trial was conducted in 189 volunteers aged 50-85 y. The subjects had no history of hypertension, anemia, asthma, cancer, or cardiovascular or digestive disease and did not regularly consume multiple or B vitamin supplements or highly fortified breakfast cereal. Subjects were randomly assigned to consume 1 cup (0.24 L) breakfast cereal fortified with 440 microg folic acid, 1.8 mg vitamin B-6, and 4.8 microg vitamin B-12 or placebo cereal for 12 wk. Blood was drawn at 0, 2, 12, and 14 wk. Methionine-loading tests were conducted at baseline and week 14.

RESULTS

Final baseline-adjusted plasma homocysteine concentrations were significantly lower and B vitamin concentrations were significantly higher in the treatment group than in the placebo group (P < 0.001). The percentage of subjects with plasma folate concentrations < 11 nmol/L decreased from 2% to 0%, with vitamin B-12 concentrations < 185 pmol/L from 9% to 3%, with vitamin B-6 concentrations < 20 nmol/L from 6% to 2%, and with homocysteine concentrations > 10.4 micromol/L (women) or > 11.4 micromol/L (men) from 6.4% to 1.6%. The percentage of control subjects with values beyond these cutoff points remained nearly constant or increased.

CONCLUSIONS

In this relatively healthy group of volunteers, consumption of 1 cup fortified breakfast cereal daily significantly increased B vitamin and decreased homocysteine concentrations, including post-methionine-load homocysteine concentrations.

Metabolism and function of coenzyme Q

Coenzyme Q (CoQ) is present in all cells and membranes and in addition to be a member of the mitochondrial respiratory chain it has also several other functions of great importance for the cellular metabolism. This review summarizes the findings available to day concerning CoQ distribution, biosynthesis, regulatory modifications and its participation in cellular metabolism. There are a number of indications that this lipid is not always functioning by its direct presence at the site of action but also using e.g. receptor expression modifications, signal transduction mechanisms and action through its metabolites. The biosynthesis of CoQ is studied in great detail in bacteria and yeast but only to a limited extent in animal tissues and therefore the informations available is restricted. However, it is known that the CoQ is compartmentalized in the cell with multiple sites of biosynthesis, breakdown and regulation which is the basis of functional specialization. Some regulatory mechanisms concerning amount and biosynthesis are established and nuclear transcription factors are partly identified in this process. Using appropriate ligands of nuclear receptors the biosynthetic rate can be increased in experimental system which raises the possibility of drug-induced upregulation of the lipid in deficiency. During aging and pathophysiological conditions the tissue concentration of CoQ is modified which influences cellular functions. In this case the extent of disturbances is dependent on the localization and the modified distribution of the lipid at cellular and membrane levels.

Decreased levels of coenzyme Q(10) in patients with bronchial asthma

BACKGROUND

The contribution of free oxygen radicals in the pathogenesis of bronchial asthma is generally accepted. The modulation of antioxidative defence by supplementation with antioxidants represents additive therapy in complex management of disease. The aim of the study was to assess the levels of coenzyme Q10, alpha-tocopherol, and beta-carotene both in plasma and whole blood, and malondialdehyde (MDA) and eosinophil cationic protein (ECP) in plasma of asthmatics (As).

METHODS

Fifty-six As (15 males and 41 females) aged from 19 to 72 years (mean age 46 years) suffering from allergic asthma were enrolled into the study. The control group comprised 25 healthy volunteers (16 males, 9 females) aged 25-50 years.

RESULTS

The concentrations of CoQ10 decreased significantly both in plasma and whole blood, compared with healthy volunteers (0.34 +/- 0.15 micromol/l vs. 0.52 +/- 0.15 micromol/l, 0.33 +/- 0.14 micromol/l vs. 0.50 +/- 0.13 micromol/l, P < 0.001, P< 0.001, respectively). The levels of alpha-tocopherol were decreased both in plasma and whole blood in comparison with controls [24.10 micromol/l (19.8; 30.5), vs. 33.20 micromol/l (28.25; 38.05), 17.22 +/- 6.45 micromol/l vs. 21.58 +/- 7.92 micromol/l, P= 0.006, P = 0.01, respectively]. The levels of MDA were elevated over the reference range in both groups (reference range < 4.5 micromol/l). No changes were seen in beta-carotene concentrations. Positive correlation was found between whole blood CoQ10 and alpha-tocopherol concentrations.

CONCLUSION

Results of the study suggest a possible contribution of suboptimal concentrations of CoQ10 on antioxidative dysbalance in As and provide a rationale for its supplementation.

Human aging and global function of coenzyme Q10

In this paper, we review two parts of our recent work on human skeletal muscle. The first part mainly describes changes occurring during aging, whereas the second part discusses the functions of coenzyme Q10 (CoQ10), particularly in relation to the aging process. During the lifetime of an individual, mtDNA undergoes a variety of mutation events and rearrangements. These mutations and their consequent bioenergenic decline, together with nuclear DNA damage, contribute to the reduced function of cells and organs, especially in postmitotic tissues. In skeletal muscle, this functional decline can be observed by means of changes with age in fiber type profile and the reduction in the number and size of the muscle fibers. In addition to the functions of coenzyme Q10 as an electron carrier in the respiratory chain and as an antioxidant, CoQ10 has been shown to regulate global gene expression in skeletal muscle. We hypothesize that this regulation is achieved via superoxide formation with H2O2 as a second messenger to the nucleus.

Adenocarcinomas of the esophagus and gastric cardia: the role of diet

The incidence of adenocarcinomas of the esophagus and gastric cardia (ACEGC) has been increasing for the past 10-15 years in the United States. The reason for this increase is unknown. This hospital-based case-control study was conducted to assess the effects of dietary and nutritional factors on the risk of ACECG. A total of 95 incident cases with pathological diagnosis and 132 cancer-free controls were included in the study. Patients were recruited at Memorial Sloan-Kettering Cancer Center from 1 November 1992 to 1 November 1994. Epidemiologic data were collected by a modified National Cancer Institute Health Habits History Questionnaire. Nutritional and dietary factors were analyzed using a logistic regression model. Increased risk of ACEGC was significantly related to higher intake of dietary calories and fat after controlling for several potential confounding factors. Decreased risk of ACEGC was significantly associated with high ingestion of dietary fiber, lutein, niacin, vitamin B6, iron, and zinc. Higher intakes of vitamin A, beta-carotene, vitamin E, folate, phosphorus, and potassium were associated with a decreased risk of the disease, but these were not statistically significant. The study suggests that ACEGC can be preventable through dietary interventions.

Effect of micronutrient status on natural killer cell immune function in healthy free-living subjects aged >/=90 y

BACKGROUND

Natural killer (NK) cells play a role in natural immunity against tumor and infected cells. Advanced aging is associated with functional impairment of NK cells and increased susceptibility to nutritional deficiencies.

OBJECTIVE

Our objective was to test whether micronutrient status affects NK cell activity in an older population.

DESIGN

The relations between NK cell variables (percentage of leukocytes and cytotoxicity) and blood concentrations of selected micronutrients were studied in 62 healthy, free-living northern Italian subjects (25 men, 37 women) aged 90-106 y. Anthropometric measurements were also made.

RESULTS

All subjects were well nourished according to age-specific anthropometric norms but many of them had micronutrient deficiencies. The prevalence of micronutrient deficiency was highest for selenium (in approximately 50% of both sexes), zinc (in 52% of men and 41% of women), and vitamin B-6 (in 40% of men and 59% of women), followed by vitamin A (in 16% of men and 27% of women) and vitamin E, vitamin B-12, and folate (each in <10% of both sexes). Ubiquinone-10 status was inadequate in 40% of women and 24% of men (P = 0.02). The percentage of NK cells was associated with serum zinc (men: r = 0.573, P = 0. 007; women: r = 0.373, P = 0.031) and selenium (women: r = 0.409, P = 0.018) concentrations. In women only, NK cell cytotoxicity at different effector-target cell ratios was positively associated with plasma vitamin E and ubiquinone-10 concentrations (P < 0.05). No significant associations with NK cell variables were found for the other measured nutrients.

CONCLUSIONS

The results of this study strengthen the hypothesis that individual micronutrients may affect the number and function of NK cells in old age. The study also confirms the high prevalence of micronutrient deficiencies in healthy and apparently well-nourished persons aged >/=90 y.

Growth, development and differentiation: a functional food science approach

Few other aspects of food supply and metabolism are of greater biological importance than the feeding of mothers during pregnancy and lactation, and of their infants and young children. Nutritional factors during early development not only have short-term effects on growth, body composition and body functions but also exert long-term effects on health, disease and mortality risks in adulthood, as well as development of neural functions and behaviour, a phenomenon called 'metabolic programming'. The interaction of nutrients and gene expression may form the basis of many of these programming effects and needs to be investigated in more detail. The relation between availability of food ingredients and cell and tissue differentiation and its possible uses for promoting health and development requires further exploration. The course of pregnancy, childbirth and lactation as well as human milk composition and the short- and long-term outcome of the child are influenced by the intake of foods and particularly micronutrients, e.g. polyunsaturated fatty acids, Fe, Zn and I. Folic acid supplementation from before conception through the first weeks of pregnancy can markedly reduce the occurrence of severe embryonic malformations; other potential benefits of modulating nutrient supply on maternal and child health should be further evaluated. The evaluation of dietary effects on child growth requires epidemiological and field studies as well as evaluation of specific cell and tissue growth. Novel substrates, growth factors and conditionally essential nutrients (e.g. growth factors, amino acids, polyunsaturated fatty acids) may be potentially useful as ingredients in functional foods and need to be assessed carefully. Intestinal growth, maturation, and adaptation as well as long-term function may be influenced by food ingredients such as oligosaccharides, gangliosides, high-molecular-mass glycoproteins, bile salt-activated lipase, pre- and probiotics. There are indications for some beneficial effects of functional foods on the developing immune response, for example induced by antioxidant vitamins, trace elements, fatty acids, arginine, nucleotides, and altered antigen contents in infant foods. Peak bone mass at the end of adolescence can be increased by dietary means, which is expected to be of long-term importance for the prevention of osteoporosis at older ages. Future studies should be directed to the combined effects of Ca and other constituents of growing bone, such as P, Mg and Zn, as well as vitamins D and K, and the trace elements F and B. Pregnancy and the first postnatal months are critical time periods for the growth and development of the human nervous system, processes for which adequate substrate supplies are essential. Early diet seems to have long-term effects on sensory and cognitive abilities as well as behaviour. The potential beneficial effects of a balanced supply of nutrients such as I, Fe, Zn and polyunsaturated fatty acids should be further evaluated. Possible long-term effects of early exposure to tastes and flavours on later food choice preferences may have a major impact on public health and need to be further elucidated. The use of biotechnology and recombinant techniques may offer the opportunity to include various bioactive substances in special dietary products, such as human milk proteins, peptides, growth factors, which may have beneficial physiological effects, particularly in infancy and early childhood.

Vitamins and immunomodulation in AIDS

Acquired immune deficiency syndrome (AIDS) is a clinical disorder caused by a retrovirus infection and represents the end point in a progressive sequence of immunosuppressive changes. Vitamins can enhance disease resistance in animals and humans. As such they are important co-factors in optimal functioning of the immune systems. In this article, the immunological and nutritional modifications caused by AIDS are summarized. The effects of murine and human retrovirus infection on vitamin status are analyzed as co-factors in the development of severe immune dysfunction, AIDS. The properties of immunoenhancing antioxidative vitamins, vitamin A, B6, B12, C, E, and beta-carotene, which are frequently low in AIDS patients, are evaluated relative to the development of immunodeficiency during retrovirus infection. Vitamin A, E, and B12 deficiency accelerated the development of AIDS with low T cells, whereas their normalization retarded the development of immune dysfunction. The interactions between these vitamins and the immune system in human AIDS patients and animal models of AIDS are reviewed. Our purpose is to provide data on how retrovirus infection can cause nutritional deficiencies that accentuate immune damage and to evaluate the potential therapeutic role of vitamins in the treatment of immune dysfunctions in AIDS patients.

Mitochondrial medicine

In the mitochondrion, inherited defects have been identified in the electron transport system by which ATP is formed, as well as in the transport and metabolism of fuels. Clinical findings in diseases due to these defects can be related to abnormal accumulations of metabolic intermediates and inadequate or inefficient ATP generation. In the oxidative process within the mitochondrion, chemical oxidants are generated, which can cause cellular damage. As the body's defences against the oxidants decline, oxidative damage appears to contribute to the ageing process itself as well as to age-related degenerative diseases. Understanding in this area has accelerated with knowledge of the synthesis, structure and function of the mitochondrion and its specific DNA. The frontier is expected to advance rapidly as causal relationships between these diseases and mitochondrial dysfunction, and the potential role of antioxidants in therapy, are better defined.

Oxidative damage and mitochondrial decay in aging

We argue for the critical role of oxidative damage in causing the mitochondrial dysfunction of aging. Oxidants generated by mitochondria appear to be the major source of the oxidative lesions that accumulate with age. Several mitochondrial functions decline with age. The contributing factors include the intrinsic rate of proton leakage across the inner mitochondrial membrane (a correlate of oxidant formation), decreased membrane fluidity, and decreased levels and function of cardiolipin, which supports the function of many of the proteins of the inner mitochondrial membrane. Acetyl-L-carnitine, a high-energy mitochondrial substrate, appears to reverse many age-associated deficits in cellular function, in part by increasing cellular ATP production. Such evidence supports the suggestion that age-associated accumulation of mitochondrial deficits due to oxidative damage is likely to be a major contributor to cellular, tissue, and organismal aging.