Type 2 diabetes mellitus is associated with an increased risk of dementia, potentially through multifactorial pathologies, including neuroinflammation. Therefore, there is a need to identify novel agents that can suppress neuroinflammation and prevent cognitive impairment in diabetes. In the present study, we demonstrated that a high-glucose (HG) environment elevates the intracellular reactive oxygen species (ROS) levels and triggers inflammatory responses in the mouse microglial cell line BV-2. We further found that thioredoxin-interacting protein (TXNIP), a ROS-responsive positive regulator of the nucleotide-binding oligomerization domain (NOD)-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, was also upregulated, followed by NLRP3 inflammasome activation and subsequent interleukin-1beta (IL-1β) production in these cells. Conversely, caspase-1 was not significantly activated, suggesting the involvement of noncanonical pathways in these inflammatory responses. Moreover, our results demonstrated that taxifolin, a natural flavonoid with antioxidant and radical scavenging activities, suppressed IL-1β production by reducing the intracellular ROS levels and inhibiting the activation of the TXNIP–NLRP3 axis. These findings suggest the novel anti-inflammatory effects of taxifolin on microglia in an HG environment, which could help develop novel strategies for suppressing neuroinflammation in diabetes.

Type 2 diabetes mellitus (T2DM) is an epidemiological risk factor for dementia and has been implicated in multifactorial pathologies, including neuroinflammation. In the present study, we aimed to elucidate the potential anti-inflammatory effects of imeglimin, a novel antidiabetic agent, on high-glucose (HG)-stimulated microglia. Mouse microglial BV2 cells were stimulated with HG in the presence or absence of imeglimin. We examined the effects of imeglimin on the levels of proinflammatory cytokines, intracellular reactive oxygen species (ROS), mitochondrial integrity, and components related to the inflammasome or autophagy pathways in these cells. Our results showed that imeglimin suppressed the HG-induced production of interleukin-1beta (IL-1β) by reducing the intracellular ROS levels, ameliorating mitochondrial dysfunction, and inhibiting the activation of the thioredoxin-interacting protein (TXNIP)–NOD-like receptor family pyrin domain containing 3 (NLRP3) axis. Moreover, the inhibitory effects of imeglimin on the TXNIP–NLRP3 axis depended on the imeglimin-induced activation of ULK1, which also exhibited novel anti-inflammatory effects without autophagy induction. These findings suggest that imeglimin exerted novel suppressive effects on HG-stimulated microglia through the ULK1–TXNIP–NLRP3 axis, and may, thereby, contribute to the development of innovative strategies to prevent T2DM-associated cognitive impairment.

Background/Objectives: We aimed to identify questionnaire items associated with an increased risk of developing hepatic steatosis in the general population. Methods: A total of 15,063 individuals aged ≥20 years who underwent general health checkups and had no hepatic steatosis at baseline were included. The relationship between questionnaire data at baseline and hepatic steatosis incidence over a median 4.2-year follow-up was investigated across body mass index (BMI) categories. Results: Among 15,063 individuals (mean [SD] age, 47.1 [10.2] years; 6769 [44.9%] male; mean [SD] BMI, 21.4 [2.6] kg/m²), 1889 individuals (12.5%) developed hepatic steatosis during follow-up. After adjusting for age, sex, and factors related to metabolic diseases and liver injury, the strongest questionnaire-based risk factor for hepatic steatosis was self-reported weight gain of 10 kg or more after the age of 20 across all BMI categories: total population (hazard ratio [HR], 2.11; 95% confidence interval [CI], 1.90–2.34; p < 0.001), Category 1 (BMI < 22) (HR, 2.33; 95% CI, 1.86–2.91; p < 0.001), Category 2 (BMI 22 to <25) (HR, 1.43; 95% CI, 1.25–1.63; p < 0.001), and Category 3 (BMI ≥ 25) (HR, 1.41; 95% CI, 1.12–1.77; p = 0.003). Conclusions: In this cohort study, self-reported weight gain of 10 kg or more after the age of 20 was associated with an increased risk of hepatic steatosis, independent of baseline BMI. Questionnaires capturing weight gain history may support universal screening efforts to identify individuals at elevated risk.