Plectin, a widespread intermediate filament-based cytolinker protein capable of interacting with a variety of cytoskeletal structures and plasma membrane-bound junctional complexes, serves essential functions in maintenance of cell and tissue cytoarchitecture. We have generated a mouse line bearing floxed plectin alleles and conditionally deleted plectin in stratified epithelia. This strategy enabled us to study the consequences of plectin deficiency in this particular type of tissues in the context of the whole organism without plectin loss affecting other tissues. Conditional knockout mice died early after birth, showing signs of starvation and growth retardation. Blistering was observed on their extremities and on the oral epithelium after initial nursing, impairing food uptake. Knockout epidermis was very fragile and showed focal epidermal barrier defects caused by the presence of small skin lesions. Stratification, proliferation and differentiation of knockout skin seemed unaffected by epidermis-restricted plectin deficiency. In an additionally generated mouse model, tamoxifen-induced Cre-ERT-mediated recombination led to mice with a mosaic plectin deletion pattern in adult epidermis, combined with microblister formation and epidermal barrier defects. Our study explains the early lethality of plectin-deficient mice and provides a model to ablate plectin in adult animals which could be used for developing gene or pharmacological therapies.

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver a scientific opinion on Yarrowia lipolytica yeast biomass as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is the dried and heat-killed biomass of Yarrowia lipolytica, a yeast species that is widespread in nature and which can be found in the environment as well as in foods. The production process is sufficiently described and does not raise safety concerns. The information provided on the composition of the NF is sufficient and does not raise safety concerns. The applicant proposed to use the NF as a food supplement in the form of capsules, tablets or powder. The target population for the NF is the general population above 3 years of age. The maximum proposed daily use levels are 3 g/day for children from 3 years to less than 10 years of age and 6 g/day thereafter. Taking into account the composition of the NF and the proposed use levels, the consumption of the NF is not nutritionally disadvantageous. No relevant toxicological information was provided. The Panel considers that given the qualified presumption of safety (QPS) status for production purposes of Yarrowia lipolytica and the fact that the production process of the NF does not raise safety concerns, no toxicological studies are needed for the safety assessment of the NF. The Panel concludes that the NF, Yarrowia lipolytica yeast biomass, is safe under the proposed conditions of use.

Following a request from the European Commission, the Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on the safety of astaxanthin when used as a novel food in food supplements at maximum levels of 8 mg/day, taking into account the overall cumulative intake of astaxanthin from all food sources. In 2014, the NDA Panel assessed the safety of the novel astaxanthin‐rich ingredient derived from microalgae Haematococcus pluvialis in the context of an application submitted under Regulation (EC) No 258/1997. In that opinion, the NDA Panel considered that the acceptable daily intake (ADI) for astaxanthin was 0.034 mg/kg body weight (bw) set by the EFSA FEEDAP Panel in 2014. In 2019, the FEEDAP Panel adopted an opinion which concerned the renewal of the authorisation of dimethyldisuccinate‐astaxanthin and a new use of the additive for crustaceans and other fish than salmonids. In that assessment, the FEEDAP Panel derived a new ADI of 0.2 mg astaxanthin/kg bw which replaced the ADI of 0.034 mg/kg bw established in 2014. By taking into account an updated exposure assessment for astaxanthin from the background diet (fish and crustaceans) in combination with 8 mg from food supplements, the NDA Panel concludes that (i) such combined exposure to astaxanthin is safe for adults, (ii) 14 to < 18 years old adolescents reach the ADI, and (iii) the ADI is exceeded by 28% in children aged 10 to < 14 years and up to 524% in infants aged 4–6 months.

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