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The liver has a high demand for phosphatidylcholine (PC), particularly in overnutrition, where reduced phospholipid levels have been implicated in the development of nonalcoholic fatty liver disease (NAFLD). Whether other pathways exist in addition to de novo PC synthesis that contribute to hepatic PC pools remains unknown. Here, we identified the lysophosphatidylcholine (LPC) transporter major facilitator superfamily domain containing 2A (Mfsd2a) as critical for maintaining hepatic phospholipid pools. Hepatic Mfsd2a expression was induced in patients having NAFLD and in mice in response to dietary fat via glucocorticoid receptor action. Mfsd2a liver-specific deficiency in mice ( L2aKO ) led to a robust nonalcoholic steatohepatitis–like (NASH-like) phenotype within just 2 weeks of dietary fat challenge associated with reduced hepatic phospholipids containing linoleic acid. Reducing dietary choline intake in L2aKO mice exacerbated liver pathology and deficiency of liver phospholipids containing polyunsaturated fatty acids (PUFAs). Treating hepatocytes with LPCs containing oleate and linoleate, two abundant blood-derived LPCs, specifically induced lipid droplet biogenesis and contributed to phospholipid pools, while LPC containing the omega-3 fatty acid docosahexaenoic acid (DHA) promoted lipid droplet formation and suppressed lipogenesis. This study revealed that PUFA-containing LPCs drive hepatic lipid droplet formation, suppress lipogenesis, and sustain hepatic phospholipid pools — processes that are critical for protecting the liver from excess dietary fat.

The urban conglomeration has accentuated the role of urban greenery as a determinant factor for sustainable living, especially in highly dense cities. The country of Singapore has consistently attempted to develop and rehabilitate urban greenery by attempting to align the green space policy with the pursuit of better life quality. In this study, we assess the benefits arising from the rehabilitated Bishan-Ang Mo Kio (AMK) Park in north Singapore and the effects on economic welfare. The Bishan-AMK Park was initially constructed in the late 70 s as a drainage area for the avoidance of flooding incidents. In 2012, a pilot project was introduced to create a blue-green infrastructure (BGI) space for the provision of drainage and flood prevention but also for recreational and environmental improvement in the area. Yet, the benefits emerging from BGI are not well explored and still underestimated. To this extent, we evaluate selected services related to recreational, socio-cultural and tourism-related values by indicating the economic benefits from the introduction of BGI in condensed urban environments like Singapore. The findings indicate that the benefits deriving from the selected services could be within the range of US$100 million to US$220 million with a mean value of US$160 million per year by substantially contributing to human well-being. The assessment of environmental services can raise the awareness of residents and local authorities on the contribution of urban greenery to livelihoods and economic development in Singapore and similar densely populated areas.