Obesity and metabolic syndrome (MS) associated with excess calorie intake has become a great public health concern worldwide. L-arabinose, a naturally occurring plant pentose, has a promising future as a novel food ingredient with benefits in MS; yet the mechanisms remain to be further elucidated. Gut microbiota is recently recognized to play key roles in MS. Molecular hydrogen, an emerging medical gas with reported benefits in MS, can be produced and utilized by gut microbes. Here we show oral L-arabinose elicited immediate and robust release of hydrogen in mice in a dose-and-time-dependent manner while alleviating high-fat-diet (HFD) induced MS including increased body weight especially fat weight, impaired insulin sensitivity, liver steatosis, dyslipidemia and elevated inflammatory cytokines. Moreover, L-arabinose modulated gene-expressions involved in lipid metabolism and mitochondrial function in key metabolic tissues. Antibiotics treatment abolished L-arabinose-elicited hydrogen production independent of diet type, confirming gut microbes as the source of hydrogen. q-PCR of fecal 16S rDNA revealed modulation of relative abundances of hydrogen-producing and hydrogen-consuming gut microbes as well as probiotics by HFD and L-arabinose. Our data uncovered modulating gut microbiota and hydrogen yield, expression of genes governing lipid metabolism and mitochondrial function in metabolic tissues is underlying L-arabinose’s benefits in MS.

Senile and disuse osteoporosis have distinct bone turnover status and lack effective treatments. In this study, senescence-accelerated mouse prone 8 (SAMP8) and hindlimb unloading mouse models were used to explore the protective effects of daphnetin on these two types of osteoporosis, and primary osteoblasts and bone marrow monocyte-derived osteoclasts, as well as pre-osteoblast MC3T3-E1, and osteoclast precursor RAW264.7 cells were used to investigate the underlying mechanisms. The results showed that daphnetin administration effectively improved bone remodeling in both senile and disuse osteoporosis, but with different mechanisms. In senile osteoporosis with low bone turnover, daphnetin inhibited NOX2-mediated ROS production in osteoblasts, resulting in accelerated osteogenic differentiation and bone formation, while in disuse osteoporosis with high bone turnover, daphnetin restored SIRT3 expression, maintained mitochondrial homeostasis, and additionally upregulated SOD2 to eliminate ROS in osteoclasts, resulting in attenuation of osteoclast differentiation and bone resorption. These findings illuminated that daphnetin has promising potential for the prevention and treatment of senile and disuse osteoporosis. The different mechanisms may provide clues and basis for targeted prevention and treatment of osteoporosis according to distinct bone turnover status.

Neuroinflammation driven by microglial activation is a hallmark of Alzheimer’s disease (AD). Triggering receptor expressed on myeloid cells 2 (TREM2) is a key regulator of microglial inflammation, yet strategies to modulate its expression remain limited. Safflower leaves, a vegetable rich in flavonoids—particularly luteolin—were previously shown to attenuate neuroinflammation, reduce oxidative stress, and ameliorate cognitive impairment in APP/PS1 mice. Here, we demonstrated that safflower leaves inhibit microglial inflammation and upregulate TREM2 in APP/PS1 mice. Luteolin, the major active flavonoid in safflower leaves, exerted anti-inflammatory effects in lipopolysaccharides (LPS)-activated microglia. Mechanistically, luteolin enhanced Trem2 transcription by activating forkhead box protein O3 (FOXO3), a novel transcriptional regulator of Trem2 identified through promoter analysis. FOXO3 binding to the Trem2 promoter was essential for this regulation, and luteolin further promoted FOXO3 nuclear translocation. Crucially, Trem2 knockdown attenuated luteolin’s anti-inflammatory effects, confirming TREM2 as a key mediator. Overall, our study reveals the FOXO3-TREM2 axis as a potential therapeutic target for neuroinflammation and highlights luteolin present in safflower leaves as a candidate dietary intervention for AD, providing new mechanistic insights into the anti-inflammatory activity of this natural antioxidant.

The prevalence of sleep deprivation is increasing worldwide. Despite the vital roles that the liver plays in metabolism and immune response, hepatic dysfunctions in acute sleep deprivation (ASD) and chronic sleep deprivation (CSD) remain underexplored. Additionally, the effects of the newly developed chalcone analog, 1-(2,3,4-trimethoxyphenyl)-2-(3,4,5-trimethoxyphenyl)-acrylketone (TAK), were evaluated as a potential therapeutic chemical for mitigating SD-induced hepatic damage. A modified multi-platform method was employed to prepare animal models of 72 h ASD and 21-day CSD in rats. TAK (50 mg/kg/day) was administered through irrigation starting one week before the experiment and continuing until the end. ASD triggered hepatic lipid accumulation and inflammation, whereas CSD resulted in pathological portal area expansion and fibrosis, with comparatively fewer disturbances in liver metabolism and inflammation. TAK effectively alleviated ASD-induced disruptions in glycogen synthesis via PI3K/AKT/GSK3/GYS2 pathways, abnormal lipid accumulation via SREBP1/FASN/ACC, liver inflammation by balancing M1 and M2 macrophages, and liver fibrosis induced by ASD/CSD. This study provides valuable insights into the different mechanisms of liver damage induced by severe ASD and mild CSD. Additionally, TAK has been proposed as a potential therapeutic strategy for ultimate SD-related hepatic complications.