Combined effects of nitrogen limitation and overexpression of malic enzyme gene on lipid accumulation in Dunaliella parva.

Overexpression of Dunaliella parva (D. parva) malic enzyme (ME) gene (DpME) significantly increased DpME expression and ME enzyme activity in transgenic D. parva. Nitrogen limitation had an inhibitory effect on protein content, and DpME overexpression could improve protein content. Nitrogen limitation increased carbohydrate content, and Dunaliella parva overexpressing malic enzyme gene under nitrogen limitation (DpME-N-) group showed the lowest starch content among all groups. Dunaliella parva overexpressing malic enzyme gene under nitrogen sufficient condition (DpME) and DpME-N- groups showed considerably high mRNA levels of DpME. ME activity was significantly enhanced by DpME overexpression, and nitrogen limitation caused a smaller increase. DpME overexpression and nitrogen limitation obviously enhanced lipid accumulation, and DpME overexpression had more obvious effect. Compared with control (wild type), lipid content (68.97%) obviously increased in DpME-N- group. This study indicated that the combination of DpME overexpression and nitrogen limitation was favorable to the production of microalgae biodiesel.

Tracking cognitive trajectories in older survivors of COVID-19 up to 2.5 years post-infection.

Emerging evidence suggests that neurological and other post-acute sequelae of COVID-19 can persist beyond or develop following SARS-CoV-2 infection. However, the long-term trajectories of cognitive change after a COVID-19 infection remain unclear. Here we investigated cognitive changes over a period of 2.5 years among 1,245 individuals aged 60 years or older who survived infection with the original SARS-CoV-2 strain in Wuhan, China, and 358 uninfected spouses. We show that the overall incidence of cognitive impairment among older COVID-19 survivors was 19.1% at 2.5 years after infection and hospitalization, evaluated using the Telephone Interview for Cognitive Status-40. Cognitive decline primarily manifested in individuals with severe COVID-19 during the initial year of infection, after which the rate of decline decelerated. Severe COVID-19, cognitive impairment at 6 months and hypertension were associated with long-term cognitive decline. These findings reveal the long-term cognitive trajectory of the disease and underscore the importance of post-infection cognitive care for COVID-19 survivors.

Prepuberty is a window period for curcumin to prevent obesity in postnatal overfed rats.

BACKGROUND: Overnutrition in early life increases the risk of obesity and metabolic diseases. We investigated the effects and the window period of a curcumin (CUR) diet on postnatal overfed rats. METHODS: Male rats aged 3 days were randomly divided into normal litters (NL, 10 pups/litter) and small litters (SL, 3 pups/litter). After weaning (Week 3, W3), NL rats were fed a normal diet (NL) and SL rats were fed a normal diet (SL) or 2% CUR diet from weaning (W3) (SL-CURW13), beginning of puberty (W6) (SL-CURW16), or end of puberty (W8) (SL-CURW18) for 10 weeks. RESULTS: Body weight, glucose intolerance and hyperlipidemia in the SL rats were higher than in the NL rats, especially after puberty. After the CUR intervention, SL-CURW13 and SL-CURW16 rats showed lower body weight gain, adipose tissue weight and mRNA level of C/EBPα in SAT, along with higher mRNA levels of ß-catenin. There was no difference between SL and SL-CURW18 rats. Glucose tolerance, serum lipids and hepatic lipids recovered to normal in the SL-CURW13 rats, but only partially in the SL-CURW16 and SL-CURW18 rats. CONCLUSION: Prepuberty is a window period for CUR intervention to improve programmed outcomes in postnatal overfed rats. IMPACT: Overnutrition during the first 1000 days of life has persistent negative effects on metabolism. Strategies should be taken to prevent overnutrition in early life to reduce the risk of obesity and metabolic disease in later life. A small-litter rat model was utilized to simulate early-life overnutrition in humans. We investigated the different effects and critical period for curcumin intervention on postnatal overfed rats. Dietary curcumin intervention before puberty could effectively transform nutritional programming to reduce obesity and metabolic disorders caused by early-life overnutrition, and an earlier intervention might predict a better outcome.