Retinoids are micronutrients that are stored as retinyl esters in the retina and hepatic stellate cells (HSCs). HSCs are key players in fibrogenesis in chronic liver diseases. The enzyme responsible for hydrolysis and release of retinyl esters from HSCs is unknown and the relationship between retinoid metabolism and liver disease remains unclear. We hypothesize that the patatin-like phospholipase domain-containing 3 (PNPLA3) protein is involved in retinol metabolism in HSCs. We tested our hypothesis both in primary human HSCs and in a human cohort of subjects with non-alcoholic fatty liver disease (N = 146). Here we show that PNPLA3 is highly expressed in human HSCs. Its expression is regulated by retinol availability and insulin, and increased PNPLA3 expression results in reduced lipid droplet content. PNPLA3 promotes extracellular release of retinol from HSCs in response to insulin. We also show that purified wild-type PNPLA3 hydrolyzes retinyl palmitate into retinol and palmitic acid. Conversely, this enzymatic activity is markedly reduced with purified PNPLA3 148M, a common mutation robustly associated with liver fibrosis and hepatocellular carcinoma development. We also find the PNPLA3 I148M genotype to be an independent (P = 0.009 in a multivariate analysis) determinant of circulating retinol-binding protein 4, a reliable proxy for retinol levels in humans. This study identifies PNPLA3 as a lipase responsible for retinyl-palmitate hydrolysis in HSCs in humans. Importantly, this indicates a potential novel link between HSCs, retinoid metabolism and PNPLA3 in determining the susceptibility to chronic liver disease.

Understanding the intricate relationship between nutrition, hormonal balance, and gender-specific factors is crucial for developing targeted interventions to mitigate obesity-related endocrine disruptions and improve metabolic health. This narrative review examines the impact of various dietary patterns on hormonal regulation in both men and women, focusing on their effects on hormonal balance and metabolic health in the context of obesity. Calorie restriction, the Western diet, high-fat diets, low-CHO diets, plant-based diets, and the Mediterranean diet are analyzed in relation to their influence on obesity-related endocrine disruptions and metabolic health. Future research directions include investigating the specific mechanisms underlying dietary influences on hormonal regulation, addressing the gender-specific metabolic differences and body fat distribution, and exploring the dietary needs of individuals undergoing gender transition. Personalized dietary interventions tailored to individual metabolic and hormonal profiles are essential for optimizing health outcomes across the gender spectrum. By integrating gender-specific considerations into dietary recommendations, healthcare professionals can better support individuals in achieving optimal metabolic health and hormonal balance.

Nutrition during childhood and adolescence is very important for growth and can have long-term health implications. The COVID-19 lockdown caused significant changes in everyday life, including in children and adolescents. This study evaluated the effects of the first COVID-19 lockdown on eating habits and body weight in children and adolescents. An online cross-sectional survey was carried out among the parents of children (5–9 years) and adolescents (10–14 years) living in Italy. The online self-administered questionnaire included demographic and anthropometric data (reported weight and height) weight and dietary habit changes during the COVID-19 lockdown in Italy (March to June 2020). A total of 439 participants were included. We found a change in eating habits with an increase in consumption of sweet packaged snacks (34%) and processed meat (25%), as well as bread, pizza and bakery products (47%). We also found an increase in vegetable, fresh fruit and legume intake (19%), and a reduction in sweet beverage and candy intake. A total of 59.7% of the participants reported body weight gain, with adolescents gaining more than children (67% vs. 55%, p = 0.010, respectively). In children, body weight gain was associated with a change in body height and increased consumption of dairy products and sweet packaged snacks, while in adolescents it was associated with an increased intake of comfort foods and processed meat. Our data highlighted the need to carefully monitor eating behaviors to avoid the establishment of unhealthy eating habits and prevent obesity in children and adolescents during periods of self-isolation.

Numerous studies have investigated the role of the monounsaturated fatty acid and other dietary factors in the prevention of cognitive decline but the short-term effect of a low dose of extravirgin olive oil on cognitive performances in the elderly have not still been investigated. Our aim was to investigate whether the replacement of all vegetable oils with a lower amount of extravirgin olive oil, in the contest of a Mediterranean Diet, would improve cognitive performances, among elderly Italian individuals. 180 elderly individuals were randomly assigned to these treatment groups for 1 year: (1) MedDiet plus extravirgin OO, 20–30 g/day; (2) control MedDiet. The cognitive sub-test of ADAScale was used to detect cognitive decline progression over 12 months. ADAS-cog score variation after 1 year, adjusted for food groups which were different between groups, was − 1.6 ± 0.4 and − 3.0 ± 0.4 in the MedDiet and MedDiet plus extravirgin OO groups, respectively (p = 0.024). Extravirgin OO intake was 30 g ± 12 and 26 g ± 6 in the MedDiet and MedDiet plus extravirgin OO groups, respectively (p = 0.044). We demonstrated the higher short-term improvement of cognitive functions scores in individuals of the MedDiet plus low dose of extravirgin olive oil rather than MedDiet alone. Extravirgin olive oil is the best quality oil and may have a neuroprotective effect.

Background: There are several effective therapies for osteoporosis but these agents might cause serious adverse events. Lycopene intake could prevent bone loss, however studies on its effects on bone are scarce. Our aim was to investigate the effects of lycopene on osteoblast cells as well as bone mineral density and bone turnover markers in postmenopausal women.Methods: We investigated the effect of lycopene on the Wnt/β-catenin and ERK 1/2 pathways, RUNX2, alkaline phosphatase, RANKL and COL1A of Saos-2. We also carried out a pilot controlled clinical study to verify the feasibility of an approach for bone loss prevention through the intake of a lycopene-rich tomato sauce in 39 postmenopausal women.Results: Lycopene 10 µM resulted in higher β-catenin and phERK1/2 proteinVsthe vehicle (p = 0.04 and p = 0.006). RUNX2 and COL1A mRNA was induced by both 5 and 10 µM doses (p = 0.03; p = 0.03 and p = 0.03; p = 0.05) while RANKL mRNA was reduced (p < 0.05). A significant bone density loss was not detected in women taking the tomato sauce while the control group had bone loss (p = 0.002). Tomato sauce intake resulted in a greater bone alkaline phosphatase reduction than the control (18% vs 8.5%, p = 0.03).Conclusions: Lycopene activates the WNT/β-catenin and ERK1/2 pathways, upregulates RUNX2, alkaline phosphatase, COL1A and downregulates RANKL Saos-2. These processes contributed to prevent bone loss in postmenopausal women.