Impact on Isoleucine and Valine Supplementation When Decreasing Use of Medical Food in the Nutritional Management of Methylmalonic Acidemia

Food or medicine? A European regulatory perspective on nutritional therapy products to treat inborn errors of metabolism

Dietary or nutritional management strategies are the cornerstone of treatment for many inborn errors of metabolism (IEMs). Though a vital part of standard of care, the products prescribed for this are often not formally registered as medication. Instead, they are regulated as food or as food supplements, impacting the level of oversight as well as reimbursed policies. This scoping literature review explores the European regulatory framework relevant to these products and its implications for current clinical practice. Searches of electronic databases (PubMed, InfoCuria) were carried out, supplemented by articles identified by experts, from reference lists, relevant guidelines and case-law by the European Court of Justice. In the European Union (EU), nutritional therapy products are regulated as food supplements, food for special medical purposes (FSMPs) or medication. The requirements and level of oversight increase for each of these categories. Relying on lesser-regulated food products to treat IEMs raises concerns regarding product quality, safety, reimbursement and patient access. In order to ascertain whether a nutritional therapy product functions as medication and thus could be classified as such, we developed a flowchart to assess treatment characteristics (benefit, pharmacological attributes, and safety) with a case-based approach. Evaluating nutritional therapy products might reveal a justifiable need for a pharmaceutical product. A flowchart can facilitate systematically distinguishing products that function medication-like in the management of IEMs. Subsequently, finding and implementing appropriate solutions for these products might help improve the quality, safety and accessibility including reimbursement of treatment for IEMs.

Transcriptome and carotenoid profiling of different varieties of Coffea arabica provides insights into fruit color formation

The processability and ultimate quality of coffee (C offea arabica) are determined by the composition of the matured fruits. The basis of genetic variation in coffee fruit quality could be explained by studying color formation during fruit maturation. Transcriptome profiling was conducted on matured fruits of four C. arabica varieties (orange colored fruits (ORF); purple colored fruits (PF); red colored fruits (RF) and yellow colored fruits (YF)) to identify key color-regulating genes, biosynthesis pathways and transcription factors implicated in fruit color formation. A total of 39,938 genes were identified in the transcriptomes of the four C. arabica varieties. In all, 2745, 781 and 1224 differentially expressed genes (DEGs) were detected in YF_vs_PF, YF_vs_RF and YF_vs_ORF, respectively, with 1732 DEGs conserved among the three pairwise groups. Functional annotation of the DEGs led to the detection of 28 and 82 key genes involved in the biosynthesis of carotenoids and anthocyanins, respectively. Key transcription factors bHLH, MYB, NAC, MADS, and WRKY implicated in fruit color regulation were detected. The high expression levels of gene-LOC113688784 (PSY), gene-LOC113730013 (β-CHY), gene-LOC113728842 (CCD7), gene-LOC113689681 (NCED) and gene-LOC113729473 (ABA2) in YF may have accounted for the yellow coloration. The differential expression of several anthocyanin and carotenoid-specific genes in the fruits substantially account for the purple (PF), red (RF), and orange (ORF) colorations. This study provides important insights into fruit color formation and variations in C. arabica and will help to develop coffee varieties with specific color and quality traits.

Long term follow-up of the dietary intake in propionic acidemia

Long-term dietary management of Propionic acidemia (PA) includes natural protein restriction, and supplementation with medical formula enriched with leucine (Leu) and free of valine (Val), isoleucine (Ileu), methionine (Met), and threonine (Thr). As PA medical formulas have high leucine content, concerns started to arise regarding potential long-term health risks of unbalanced leucine intake. PA patients have chronically low plasma levels of Ile and Val, which led to the paradoxical need to supplement with propiogenic single amino acids (AAs). Our report takes a retrospective look at the long-term dietary management of four patients and its reflection on their plasma amino acids. The patients' total protein intake was above the recommended dietary allowance (RDA) and had a high Leu/Val and Leu/Ile intake ratios in diet. Despite adequate total protein intake, patients had chronically low plasma Ile and Val and a high plasma Leu/Val and Leu/Ile ratios, which could be attributed to high Leu intake. We conclude that the best approach to PA dietary management is to only use medical formula with patients not meeting their RDA through natural protein, and to monitor plasma amino acids levels closely.