1.
Vegan diet in young children remodels metabolism and challenges the statuses of essential nutrients.
Hovinen, T, Korkalo, L, Freese, R, Skaffari, E, Isohanni, P, Niemi, M, Nevalainen, J, Gylling, H, Zamboni, N, Erkkola, M, et al
EMBO molecular medicine. 2021;13(2):e13492
-
-
-
Free full text
-
Plain language summary
As vegan diets gain popularity amongst families, there is little known about the impact of strict plant-based diets on metabolism and micronutrient status in children, apart from reduced average growth within the norm. This small study looked at 40 Finnish children from one day centre, and compared children following an omnivore or vegetarian diet to those raised on a vegan diet. The diets were analysed, and biomarkers and metabolites were measured. The metabolic profile and nutrient status of children who followed a vegan diet from birth were distinctively different to other diet patterns, including vegetarians. The authors suggest that little animal source foods are enough to shift the metabolism of children. Dietary analysis showed that vegan children had higher folate consumption and lower protein and saturated fats intake. Despite intake appearing adequate, serum markers for fat-soluble vitamins A and D were low. While the fatty acid ALA was higher compared to omnivores, DHA and overall cholesterol were decreased. The authors concluded that the bodies own cholesterol production does not seem to compensate for a lack of dietary cholesterol in this case and it remains to be established whether lower cholesterol in vegan children are negative to health. Furthermore, the circulating amino acids pool was decreased in vegan children, particularly branch chained amino acids. The most distinct difference, however, was seen in the variance of bile acid patterns. The physiological functions of bile acids go beyond digestion, yet the consequences of diverging bile acid profiles in children’s health are unknown. In conclusion, the data shows that a strict vegan diet affects the metabolism of healthy children, but much of the long-term impact on health is currently still unclear. This article highlights some of the differences, risks and uncertainties that come with raising young children on a strictly vegan diet.
Abstract
Vegan diets are gaining popularity, also in families with young children. However, the effects of strict plant-based diets on metabolism and micronutrient status of children are unknown. We recruited 40 Finnish children with a median age 3.5 years-vegans, vegetarians, or omnivores from same daycare centers-for a cross-sectional study. They enjoyed nutritionist-planned vegan or omnivore meals in daycare, and the full diets were analyzed with questionnaires and food records. Detailed analysis of serum metabolomics and biomarkers indicated vitamin A insufficiency and border-line sufficient vitamin D in all vegan participants. Their serum total, HDL and LDL cholesterol, essential amino acid, and docosahexaenoic n-3 fatty acid (DHA) levels were markedly low and primary bile acid biosynthesis, and phospholipid balance was distinct from omnivores. Possible combination of low vitamin A and DHA status raise concern for their visual health. Our evidence indicates that (i) vitamin A and D status of vegan children requires special attention; (ii) dietary recommendations for children cannot be extrapolated from adult vegan studies; and (iii) longitudinal studies on infant-onset vegan diets are warranted.
2.
Niacin Cures Systemic NAD+ Deficiency and Improves Muscle Performance in Adult-Onset Mitochondrial Myopathy.
Pirinen, E, Auranen, M, Khan, NA, Brilhante, V, Urho, N, Pessia, A, Hakkarainen, A, Kuula, J, Heinonen, U, Schmidt, MS, et al
Cell metabolism. 2020;31(6):1078-1090.e5
-
-
-
Free full text
Plain language summary
Nicotinamide adenine dinucleotide (NAD+) metabolite and its derivatives are fundamental orchestrators of daily homeostasis in our tissues. The relative amounts of NAD forms (NAD+, NADH, NADP, and NADPH) and their cofactor functions to drive metabolism to either catabolic or anabolic direction, deciding whether nutrients are broken down to synthesize ATP (adenosine 5′-triphosphate), the cellular energy currency or used as building blocks for growth and repair. An increased NAD+ /NADH ratio is a signal for a low nutrient state activating cellular fasting responses. The main question of this study was whether NAD+ levels are depleted in mitochondrial dysfunction, as mitochondria are regulating NAD+ concentrations, and if so, whether NAD+ deficiency can be restored in the tissues of the patients. Results show that mitochondrial muscle disease causes NAD+ deficiency, a myopathy-induced vitamin B3 deficiency, a metabolic pellagra. Furthermore, NAD+ levels can be rescued by a potent NAD+ booster niacin, a vitamin B3 form. Authors conclude that their findings (1) underscore the potent role of micronutrient vitamin B3 as a metabolic modifier; (2) identify NAD+ deficiency as a contributor to mitochondrial myopathy progression; (3) point to usefulness of niacin therapy for progressive external ophthalmoplegia patients; (4) introduce blood NAD+ test as a tool to identify and follow-up NAD+ deficiency; (5) indicate that correction of metabolome and function can occur without correction of transcriptional stress responses, emphasizing importance of metabolomic analysis in follow-up of treatment efficacy.
Abstract
NAD+ is a redox-active metabolite, the depletion of which has been proposed to promote aging and degenerative diseases in rodents. However, whether NAD+ depletion occurs in patients with degenerative disorders and whether NAD+ repletion improves their symptoms has remained open. Here, we report systemic NAD+ deficiency in adult-onset mitochondrial myopathy patients. We administered an increasing dose of NAD+-booster niacin, a vitamin B3 form (to 750-1,000 mg/day; clinicaltrials.govNCT03973203) for patients and their matched controls for 10 or 4 months, respectively. Blood NAD+ increased in all subjects, up to 8-fold, and muscle NAD+ of patients reached the level of their controls. Some patients showed anemia tendency, while muscle strength and mitochondrial biogenesis increased in all subjects. In patients, muscle metabolome shifted toward controls and liver fat decreased even 50%. Our evidence indicates that blood analysis is useful in identifying NAD+ deficiency and points niacin to be an efficient NAD+ booster for treating mitochondrial myopathy.
3.
Mitochondrial encephalomyopathy and retinoblastoma explained by compound heterozygosity of SUCLA2 point mutation and 13q14 deletion.
Matilainen, S, Isohanni, P, Euro, L, Lönnqvist, T, Pihko, H, Kivelä, T, Knuutila, S, Suomalainen, A
European journal of human genetics : EJHG. 2015;(3):325-30
-
-
Free full text
-
Abstract
Mutations in SUCLA2, encoding the ß-subunit of succinyl-CoA synthetase of Krebs cycle, are one cause of mitochondrial DNA depletion syndrome. Patients have been reported to have severe progressive childhood-onset encephalomyopathy, and methylmalonic aciduria, often leading to death in childhood. We studied two families, with children manifesting with slowly progressive mitochondrial encephalomyopathy, hearing impairment and transient methylmalonic aciduria, without mtDNA depletion. The other family also showed dominant inheritance of bilateral retinoblastoma, which coexisted with mitochondrial encephalomyopathy in one patient. We found a variant in SUCLA2 leading to Asp333Gly change, homozygous in one patient and compound heterozygous in one. The latter patient also carried a deletion of 13q14 of the other allele, discovered with molecular karyotyping. The deletion spanned both SUCLA2 and RB1 gene regions, leading to manifestation of both mitochondrial disease and retinoblastoma. We made a homology model for human succinyl-CoA synthetase and used it for structure-function analysis of all reported pathogenic mutations in SUCLA2. On the basis of our model, all previously described mutations were predicted to result in decreased amounts of incorrectly assembled protein or disruption of ADP phosphorylation, explaining the severe early lethal manifestations. However, the Asp333Gly change was predicted to reduce the activity of the otherwise functional enzyme. On the basis of our findings, SUCLA2 mutations should be analyzed in patients with slowly progressive encephalomyopathy, even in the absence of methylmalonic aciduria or mitochondrial DNA depletion. In addition, an encephalomyopathy in a patient with retinoblastoma suggests mutations affecting SUCLA2.
4.
Quantitative analysis of human DNA sequences by PCR and solid-phase minisequencing.
Suomalainen, A, Syvänen, AC
Molecular biotechnology. 2000;(2):123-31
Abstract
Reliable quantification by PCR requires careful experimental design and conditions, often involving sampling of the PCR reactions at different time points or amplifying multiple dilutions of a standard DNA. We describe here an accurate, quantitative and easily automatizable solid-phase method based on competitive PCR. The PCR products are analyzed by solid-phase mini-sequencing after capture of biotinylated PCR products in streptavidin-coated microtiter wells and single-nucleotide extension of a specific detection primer by a radioactively labelled nucleotide. The results are expressed as numeric cpm-values, and the incorporated label expresses the relative amount of sequence variants in the original template mixture. We have applied the method to determination of allele frequencies in pooled DNA samples, of mitochondrial heteroplasmy, of gene copy numbers, and to forensic DNA analysis.