Punicalagin, a hydrolysable tannin of pomegranate juice, exhibits multiple biological effects, including inhibiting production of pro-inflammatory cytokines in macrophages. Autophagy, an intracellular self-digestion process, has been recently shown to regulate inflammatory responses. In this study, we investigated the anti-inflammatory potential of punicalagin in lipopolysaccharide (LPS) induced RAW264.7 macrophages and uncovered the underlying mechanisms. Punicalagin significantly attenuated, in a concentration-dependent manner, LPS-induced release of NO and decreased pro-inflammatory cytokines TNF-α and IL-6 release at the highest concentration. We found that punicalagin inhibited NF-κB and MAPK activation in LPS-induced RAW264.7 macrophages. Western blot analysis revealed that punicalagin pre-treatment enhanced LC3II, p62 expression, and decreased Beclin1 expression in LPS-induced macrophages. MDC assays were used to determine the autophagic process and the results worked in concert with Western blot analysis. In addition, our observations indicated that LPS-induced releases of NO, TNF-α, and IL-6 were attenuated by treatment with autophagy inhibitor chloroquine, suggesting that autophagy inhibition participated in anti-inflammatory effect. We also found that punicalagin downregulated FoxO3a expression, resulting in autophagy inhibition. Overall these results suggested that punicalagin played an important role in the attenuation of LPS-induced inflammatory responses in RAW264.7 macrophages and that the mechanisms involved downregulation of the FoxO3a/autophagy signaling pathway.

Diabetic nephropathy is a diabetic complication caused by chronic inflammation. As the primary polyphenol in pomegranate, punicalagin is believed to have significant anti-inflammatory properties. In this study, we established a mice model for diabetes induced by high-fat diet (HFD)/ streptozotocin (STZ) to verify the protective effect of punicalagin in vivo. The results show that the blood urea nitrogen (BUN), serum creatinine (CREA), and the urine albumin to creatinine ratio (UACR) were significantly decreased in diabetic mice after punicalagin intervention, and the symptoms of glomerular interstitial hyperplasia and glomerular hypertrophy were alleviated. Pyroptosis is an essential manner of programmed cell death in the inflammatory response; the expression of pyroptosis-related proteins such as interleukin-1 (IL-1β), cysteinyl aspartate-specific protease-1 (caspase-1), gasdermin D (GSDMD), and nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain containing protein 3 (NLRP3) was decreased in our study, which proved that the administration of punicalagin for eight weeks can significantly inhibit pyroptosis in mice. In addition, punicalagin reduced high glucose-mediated protein expressions of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 4 (NOX4) and alleviated mitochondria damage. Low expression of NOX4 inhibits the dissociation of thioredoxin (Trx) and thioredoxin-interacting protein (TXNIP) and the suppression of NLRP3 inflammasome activation. To summarize, our study provided evidence that punicalagin can alleviate diabetic nephropathy, and the effect is associated with downregulating the expression of NOX4, inhibiting TXNIP/NLRP3 pathway-mediated pyroptosis, suggesting its therapeutic implications for complications of diabetes.

Background: Pediatric overweight and obesity has become a major public health problem in China. The goal of this study is to understand overweight and obesity in preschool children in Changsha City in the context of their sleep and physical activity. These results offer feasible proposals to reduce levels of overweight and obesity among preschool children. Methods: A total of 112 preschoolers aged three to six years old were investigated using multiple stage stratified cluster sampling and simple random sampling. Questionnaires were used to collect general information about children and their families. Body mass index (BMI) was used as an indicator of overweight and obesity. Age- and sex-specific cutoff values for Chinese children and adolescents were used to determine child weight status. Children’s sedentary time was reported by caregivers, while physical activity and sleep were recorded using fitness bracelets (Misfit Shine 2). Results: The prevalence of childhood overweight and obesity were 15.2% and 9.8% respectively. Preschool-aged children travelled 11,111 ± 3357 and 10,350 ± 2973 steps per day on weekdays and weekends respectively. The number of daily steps was not statistically different between weekdays and weekends. The amount of time spent daily doing vigorous activity on weekdays and weekends was significantly different, with an average time of 20.5 ± 31.6 min and 10.3 ± 15.3 min respectively (p = 0.002). Furthermore, 10.7% and 50.9% of children used screens for more than two hours on weekdays and weekends respectively (p < 0.001). Children slept for significantly longer on weekends (8.3 ± 0.9 h) than on weekdays (8.1 ± 0.7 h) (p = 0.037). A significantly higher proportion of students also fell asleep before 10:00 p.m. on weekends (26.8%) compared to weekdays (15.2%) (p < 0.001). Parent’s BMI values were positively correlated with child BMI, the monthly household income was negatively associated with child BMI. Male children were more likely to have a higher BMI than female children. Children who were obese were also more likely to have shorter sleep times compared to children of normal weight (p = 0.047). Conclusions: There was a high prevalence of overweight and obesity among the Chinese preschool children in this study. Students also demonstrated poor sleep and physical activity habits. Future research is necessary to explore the relationship between sleep, physical activity and weight status for young children in China.

Diabetic liver injury has received increasing attention as a serious complication of type 2 diabetes. Punicalagin (PU), a major component of pomegranate polyphenols, has various biological activities such as antioxidant, anti-inflammatory, and lipid metabolism regulation. In this study, we observed the protective effect of punicalagin on a high-fat diet (HFD) and streptozotocin (STZ)-induced diabetic liver injury in mice and revealed the underlying mechanism. The results showed that fasting blood glucose (FBG), fasting serum insulin (FINS), and homeostasis model assessment for insulin resistance (HOMA-IR) in diabetic liver injury mice were significantly decreased after punicalagin intervention. Simultaneously, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), free fatty acids (FFA), malondialdehyde (MDA), and total superoxide dismutase (T-SOD) in the serum and liver were significantly decreased, with reductions in fat lesions and inflammatory cells. Mitophagy is a selective autophagy that maintains a balance between the quality and quantity of intracellular mitochondria. Studies have shown that mitophagy is closely related to the occurrence and development of diabetic liver injury. In our study, the mitochondrial membrane potential (MMP) was significantly increased in mice with diabetic liver injury after punicalagin intervention; the protein expression of Pink1, Parkin, Bnip3, LC3b, P62, manganese superoxide dismutase (MnSOD), and catalase (CAT) was significantly increased in the liver; and the activities of MnSOD and CAT in the serum and liver were significantly increased, which is consistent with the results of in vitro experiments. In summary, our study provided evidence that punicalagin could reduce the level of oxidative stress in the liver by upregulating mitophagy and the activities of antioxidant enzymes, thus having a certain protective effect against diabetic liver injury.

Left-behind children (LBC) are a newly emerged social group in China. Poor nutritional status is particularly prominent in this population. However, their food insecurity tends to attract very little attention. This study aims to investigate the relationship between food insecurity and undernutrition (stunting and anaemia) in 3 to 5-year-old LBC in rural China. Face-to-face interviews were administered to 553 LBC caregivers in 40 rural villages of Hunan Province, China. The Household Food Insecurity Access Scale (HFIAS) was used to assess household food insecurity (HFI). Dietary diversity score (DDS) and food group consumption frequency were measured by 24 h-recall and food frequency questionnaires (FFQ). Hemoglobin tests and anthropometric measurements including height and weight were measured by trained health professionals. Logistic regression was constructed to assess the association between household food insecurity and dietary diversity, stunting, and anaemia. A high prevalence of household food insecurity was determined (67.6%). The weighted prevalence of stunting and anaemia were 16.6% and 26.5%, respectively. Food insecurity was positively associate with LBC stunting (severe HFI: OR = 6.50, 95% CI: 2.81, 15.00; moderate HFI: OR = 3.47, 95% CI: 1.60, 7.54), and anaemia (severe HFI: OR = 1.91, 95% CI: 1.02, 3.57). LBC with food insecurity had significantly lower dietary diversity than those who were food-secure (p < 0.001). The prevalence of household food insecurity among LBC in poor rural China is high and is associated with low DDS, stunting, and anaemia. Nutritional intervention programs and policies are urgently needed to reduce household food insecurity and undernutrition for this vulnerable population.