Serum 7 alpha-hydroxycholesterol as a new parameter of liver function in patients with chronic liver diseases

Safety of the extension of use of plant sterol esters as a novel food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on the safety of an extension of use of the novel food 'plant sterol esters' when added to vegetable fat spreads and to liquid vegetable fat-based emulsions for cooking and baking purposes pursuant to Regulation (EU) 2015/2283. Member States expressed concerns in relation to plant sterol oxidation products (POP) and consumption by non-target population groups. The median (0.5%) and P90 (2.28%) value of the oxidation rates of plant sterols determined by a wide range of cooking experiments were used together with exposure estimates for plant sterol when added and cooked with vegetable fat spreads and liquids. The no-observed adverse effect level (NOAEL) of a subchronic rat study and an applied default uncertainty factor of 200 served to derive levels (i.e. 0.64 mg POP/kg body weight (bw) per day) considered safe for humans. This safe level of exposure would be exceeded at the P95 by all age groups when considering the P90 oxidation rate and using EFSA's comprehensive food consumption database for assessing the potential exposure. When considering the median oxidation rate, the safe level of 0.64 mg POP/kg bw per day would be exceeded at the highest P95 intake estimates in children below 9 years of age. When considering an intake of the maximum authorised use level of 3 g plant sterols/person per day and oxidation rates of 0.5% and 2.28%, the resulting daily POP intakes per kg bw by an adult weighing 70 kg would be 0.21 and 0.98 mg/kg bw per day, respectively, the latter value exceeding 0.64 mg/kg bw per day. The Panel concludes that the safety of the intended extension of use of plant sterol esters under the proposed conditions of use has not been established.

Oncogenic roles of the cholesterol metabolite 25-hydroxycholesterol in bladder cancer

Oxysterols, such as 24S-hydroxycholesterol and 25-hydroxycholesterol are oxidation products of cholesterol generated by enzymatic reactions. The pathological effects of oxysterols have been described in multiple types of cancer, including cancers of the skin, lung, colon, breast and bile ducts. The molecular mechanisms underlying oxysterol-induced cancer initiation and progression have yet to be completely elucidated, and to the best of our knowledge, no prior data on the role of 24S-hydroxycholesterol and 25-hydroxycholesterol in bladder cancer exists. The results of the present study demonstrated that 25-hydroxycholesterol is increased in bladder cancer tissues, and that it promotes proliferation and the epithelial-to-mesenchymal transition in human T24 and RT4 bladder cancer cells. It was also observed that 25-hydroxycholesterol promotes Adriamycin resistance in T24 and RT4 cells, and that high levels of 25-hydroxycholesterol in bladder cancer are associated with a poor outcome. Therefore, 25-hydroxycholesterol, a primary metabolite of cholesterol, may serve an important role in the progression of bladder cancer.