Didymin alleviates metabolic dysfunction-associated fatty liver disease (MAFLD) via the stimulation of Sirt1-mediated lipophagy and mitochondrial biogenesis

BACKGROUND

Metabolic dysfunction-associated fatty liver disease (MAFLD) is one of the most prevalent metabolic syndromes worldwide. However, no approved pharmacological treatments are available for MAFLD. Chenpi, one kind of dried peel of citrus fruits, has traditionally been utilized as a medicinal herb for liver diseases. Didymin is a newly identified oral bioactive dietary flavonoid glycoside derived from Chenpi. In this study, we investigated the therapeutic potential of Didymin as an anti-MAFLD drug and elucidated its underlying mechanisms.

METHODS

High-fat diet (HFD)-induced MAFLD mice and alpha mouse liver 12 (AML12) cells were utilized to evaluate the effects and mechanisms of Didymin in the treatment of MAFLD. Liver weight, serum biochemical parameters, and liver morphology were examined to demonstrate the therapeutic efficacy of Didymin in MAFLD treatment. RNA-seq analysis was performed to identify potential pathways that could be affected by Didymin. The impact of Didymin on Sirt1 was corroborated through western blot, molecular docking analysis, microscale thermophoresis (MST), and deacetylase activity assay. Then, a Sirt1 inhibitor (EX-527) was utilized to confirm that Didymin alleviates MAFLD via Sirt1. Western blot and additional assays were used to investigate the underlying mechanisms.

RESULTS

Our results suggested that Didymin may possess therapeutic potential against MAFLD in vitro and in vivo. By promoting Sirt1 expression as well as directly binding to and activating Sirt1, Didymin triggers downstream pathways that enhance mitochondrial biogenesis and function while reducing apoptosis and enhancing lipophagy.

CONCLUSIONS

These suggest that Didymin could be a promising medication for MAFLD treatment. Furthermore, its therapeutic effects are mediated by Sirt1.

[Prevalence and trends of anemia among pregnant women in eight provinces of China from 2016 to 2020]

This study analyzed the anemia status and change trend of 219 835 pregnant women in eight provinces from 2016 to 2020 in the Maternal and Newborn Health Monitoring Program(MNHMP). The results showed that from 2016 to 2020, the anemia rate of pregnant women in eight provinces was 41.27%, and the rates of mild, moderate and severe anemia were 28.56%, 12.59% and 0.12% respectively; the anemia rates in eastern, central and western regions were 41.87%, 36.09% and 44.63% respectively, and the anemia rates in urban and rural areas were 39.87% and 42.23%. From 2016 to 2020, the anemia rate of pregnant women decreased from 44.93% to 38.22%, with an average annual decline of 3.86% (95%CI:-5.84%, -1.85%). The anemia rate among pregnant women of the eastern region (AAPC=-6.16%, 95%CI:-9.79%, -2.38%) fell faster than that among pregnant women of the central region (AAPC=0.71%, 95%CI:-6.59%, 8.57%) and western region (AAPC=-1.53%, 95%CI:-5.19%, 2.28%). From 2016 to 2020, the moderate anemia rate in pregnant women decreased from 14.98% to 10.74%, with an average annual decline of 8.72% (95%CI:-12.90%, -4.34%), with a statistically significant difference (P<0.05); AAPC for mild and severe anemia in pregnant women was 1.56% (95%CI: 3.44%, 0.36%) and 18.86% (95%CI: 39.88%, 9.52%), respectively, without statistically significant difference (P>0.05).

[A clinical and pathological report of delayed encephalopathy after heat stroke]

Objective: To explore the clinical manifestations, dynamic neuroimaging changes and brain histopathologic characteristics of a patient with delayed encephalopathy after heat stroke. Methods: In October 2019, the clinical manifestations, electroencephalogram, cerebrospinal fluid, imaging changes and brain histopathological characteristics of a patient with brain damage caused by heat stroke were retrospectively analyzed. Results: The patient was a 40-year-old male who suddenly appeared dizziness, unconscious, high fever when working in the high temperature environment. The EEG showed diffuse slow wave activity. Early CT was normal, and abnormal signals gradually appeared in the basal ganglia region of the thalamus after a few days. In the late, the MRI found a large area of abnormal signals under the cerebral cortex, and white matter was involved. Pathological examination of brain biopsy showed that cortical neuron loss, loose white matter changes, and significant demyelination changes, while no inflammatory cell infiltration was observed in subarachnoid space, meninges, and dermal white matter. Conclusion: Imaging examination dynamic changes of the delayed encephalopathy is important in the heat stroke, and the main pathological manifestation is demyelination.

[Correlation between systemic inflammation level and emphysema degree and bone mineral density in chronic obstructive pulmonary disease patients and its mechanism]

Objective: To study the correlation between systemic inflammation level and emphysema degree and bone mineral density in chronic obstructive pulmonary disease (COPD) patients and its possible mechanism. Methods: 90 patients with stable COPD who met the inclusion criteria and 50 controls in the physical examination center during the same period were recruited. All the enrolled objects have collected general clinical data, analyzed peripheral blood samples, measuring the Low-attenuation area of lung and CT value of lumbar 1 vertebra (L1-CT) by chest spiral CT. According to LAA%, COPD patients were divided into 36 cases of the non-emphysema group, 32cases of mild to moderate emphysema group, and 22 cases of severe emphysema group. The correlation between L1-CT value, LAA%, peripheral blood inflammatory factors, and pulmonary function indices in each group was analyzed and compared. Results: The HU value of L1-CT (107±32) in the COPD group was significantly lower than that in the control group (153±30), and the difference was statistically significant (P<0.05). The higher the LAA% in COPD patients was, the lower the value of L1-CT was, and the difference between groups was statistically significant. Compared with COPD patients in the non-emphysema group, peripheral blood neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), and C-reactive protein (CRP) were all increased in the emphysema group, and the differences were statistically significant (P<0.05). L1-CT was negatively correlated with LAA, PLR, NLR, and CRP while uncorrelated with serum concentration of calcium and phosphorus. Conclusion: The decrease in bone density in COPD patients is closely related to the degree of emphysema. It is associated with increased levels of systemic inflammation caused by COPD itself. Early and timely broad-spectrum anti-inflammatory treatment may have certain clinical significance for the prevention and treatment of comorbidity with osteoporosis.

The STING-IRF3 pathway is involved in lipotoxic injury of pancreatic β cells in type 2 diabetes

Lipotoxic injury of pancreatic β cells is an important pathological feature in type 2 diabetes mellitus (T2DM). Stimulator of interferon genes (STING) can recognize its own DNA leaked into the cytoplasm from damaged mitochondria or nuclei of the host cell, thus activating its downstream factor interferon regulatory factor 3 (IRF3), causing inflammation and apoptosis. The STING-IRF3 signaling pathway is closely related to glycolipid metabolism, but its relationship with the lipotoxicity of pancreatic β cells has rarely been reported. Here, we investigated the role of the STING-IRF3 signaling pathway in lipotoxicity-induced inflammation, apoptosis, and dysfunction of pancreatic β cells. We examined the activation of STING and IRF3 in islets of db/db mice and identified the role of the STING-IRF3 signaling pathway in palmitic acid (PA)-induced lipotoxic injury of INS-1, a rat insulinoma cell line. STING and phosphorylated IRF3 including downstream interferon-β were upregulated in islets of db/db mice and PA-induced INS-1 cells. Gene silencing of STING or IRF3 ameliorated PA-induced INS-1 cell inflammation and apoptosis, and reversed impaired insulin synthesis. Additionally, PA induced downregulation of the phosphoinositide 3-kinase-AKT signaling pathway, and impaired high glucose-stimulated insulin secretion was reversed after knockdown of STING or IRF3. Our results suggest that activation of the STING-IRF3 pathway triggers inflammation and apoptosis of pancreatic β cells, leading to β-cell damage and dysfunction. Hence, inhibition of this signaling pathway may represent a novel approach for β-cell protection in T2DM.

[The occurrence and determinants of anxiety and depression symptoms in women of six counties/ districts in China during pregnancy]

Objective: To estimate the prevalence of anxiety and depression symptoms during pregnancy among women from six districts of China and to explore the determinants of anxiety and depression during pregnancy. Methods: A cross-sectional study of maternal health status was conducted using the probability proportionate to size sampling method among pregnant women from six counties/districts in six provinces of China (Hebei, Liaoning, Fujian, Hunan, Sichuan and Yunnan). A questionnaire was completed by each of the women included in the study from August to December 2014. Women were recruited from three medical and health institutions with the most obstetrics patients in each district. A total of 4 210 pregnant women were included in the investigation. The hospital anxiety and depression (HAD) scale was applied to measure the symptoms of anxiety and depression in the pregnant women. Trend chi square test was used to assess the differences of anxiety and depression symptom among three trimesters. The multivariate logistic regression model was used to investigate potential contributory factors. Results: The detection rates for anxiety symptoms and depression symptoms during pregnancy were 8.5% (357/4 210) and 12.5% (525/4 210), respectively. The prevalence of anxiety symptoms during the first, second and third trimesters were 7.9% (110/1 392), 8.8% (124/1 413) and 8.8% (123/1 405), respectively (χ^2trend=0.89, P= 0.419). The prevalence of depression symptoms during the first, second and third trimesters were 14.0% (195/1 392), 12.6% (178/1 413) and 10.8% (152/1 405), respectively (χ²_trend=6.52, P=0.011). Multivariate logistic regression analysis showed an increased risk of anxiety and depression in women with an educational background of middle school rather than a college degree (OR=1.94, 95% CI: 1.44-2.63; OR=3.80, 95% CI: 2.45- 5.91). Furthermore, compared with planned pregnancies, women with unplanned pregnancies had a higher risk of anxiety and depression (OR=1.33, 95% CI: 1.06- 1.66; OR=1.35, 95% CI: 1.07- 1.71). Pregnant women who felt they lived in crowded residential conditions were at an increased risk of anxiety compared with those living in spacious residential environments (OR=1.82, 95% CI: 1.15- 2.87). Pregnant women with a household income of less than 10 000 yuan were at a higher risk of depression than living in a household with an income of ≥100 000 yuan (OR=1.91, 95% CI: 1.05-3.49). Similarly, multiparous women (≥2) were at higher risk of depression compared with nulliparous women (OR=1.88, 95% CI: 1.04- 3.41). Conclusion: The prevalence of anxiety and depression symptoms during pregnancy appears to be associated with several demographic factors, along with a women's obstetrical history. Lower educational background, unplanned pregnancy, the feeling of living under crowded residential conditions were all found to be risk factors for anxiety during pregnancy. Similarly, lower educational background, unplanned pregnancy, a lower household income (<10 000) and a greater number of previous deliveries were all risk factors for depression during pregnancy.

Association of N-acetyltransferase-2 polymorphism with an increased risk of coronary heart disease in a Chinese population

We investigated the possible correlations between N-acetyltransferase-2 (NAT2) gene polymorphisms and the risk of coronary heart disease (CHD). CHD patients (113) and healthy controls (118) were enrolled from the First People's Hospital of Yuhang between January 2013 and June 2014. The patients were divided into mild CHD (N = 72) and severe CHD (N = 41) subgroups. DNA samples were extracted and the distributions of NAT2 polymorphisms were examined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Clinical characteristic indexes of severe CHD patients were also examined for relevant statistical analysis. WT, M1, M2, and M3 alleles were observed in both case and control groups. PCR-RFLP identified a wild-type homozygote, WT/WT; a mutant heterozygote, WT/Mx; and a mutant homozygote, Mx/Mx (x = 1, 2, and 3) variant of the NAT2 genotype. Mx/Mx differed significantly between case and control groups (P < 0.05); the frequencies of all four alleles did not differ significantly between case and control groups (P > 0.05). Slow acetylator genotype frequencies were notably higher in the case group than in the control group (P < 0.05). Individuals with the slow acetylator genotype were at 1.97-times higher risk of CHD and also displayed higher triglyceride and lower high-density lipoprotein cholesterol levels than those with the rapid acetylator genotype (P < 0.05). Therefore, the NAT2 polymorphism was believed to be associated with increased risk of CHD, with the NAT2 slow acetylator genotype serving as a risk factor for severe CHD in a Chinese population.

Genetic variability of XRCC1 influences the treatment outcome of gastric cancer

We aimed to investigate the role of XRCC1 codon 194 (Arg>Trp), 280 (Arg>His), and 399 (Arg>Gln) polymorphisms in response to chemotherapy and the overall survival of gastric cancer patients. A total of 172 patients were recruited for our study between January 2010 and March 2012. Genotyping of the three XRCC1 codons was carried out by restriction fragment length polymorphism polymerase chain reaction. By logistic regression analysis, we found that the Trp/Trp genotype of XRCC1 194 (Arg>Trp) showed a stronger association with complete or partial response to chemotherapy compared to the Arg/Arg genotype, and the adjusted odds ratio (95%CI) was 0.17 (0.05-0.58). Moreover, the Trp/Trp genotype was associated with a higher risk of death than that with the Arg/Arg genotype based on multivariate Cox proportional hazard regression analysis, and the adjusted hazard ratio (95%CI) was 4.08 (1.20-14.19). In conclusion, we found that the XRCC1 194 (Arg>Trp) polymorphism was correlated with a better response to chemotherapy and a low risk of death in patients with gastric cancer.

Telmisartan-enhanced hypercholesterolaemic serum-induced vascular endothelial growth factor expression in immortalized human umbilical vascular endothelial cells

OBJECTIVE

To clarify whether hypercholesterolaemia can increase vascular endothelial growth factor (VEGF) expression in human umbilical vascular endothelial cells (HUVECs) through the phosphatidylinositol 3-kinase (PI3K) pathway, and whether a special angiotensin II receptor blocker, telmisartan, can attenuate VEGF expression induced by hypercholesterolaemia.

METHODS

Levels of VEGF expression, PI3K activity and angiogenesis in vitro were determined by various methods after HUVECs were incubated with hypercholesterolaemic serum or combined with telmisartan and/or wortmannin.

RESULTS

We found that hypercholesterolaemic serum (cholesterol > or = 0.08 mmol/L) can increase VEGF expression in HUVECs and that telmisartan cooperates with hypercholesterolaemic serum in promoting VEGF expression. The increased VEGF expression was associated with enhanced PI3K activity and could be significantly inhibited by wortmannin, a potent PI3K inhibitor. Likewise, hypercholesterolaemic serum significantly promoted angiogenesis in vitro, which could be inhibited when PI3K activity was suppressed.

CONCLUSIONS

Our study suggests that hypercholesterolaemic serum induces VEGF expression through PI3K in HUVECs and that telmisartan cooperates with hypercholesterolaemia in promoting VEGF expression.

Effect of several organic acids on phosphate adsorption by variable charge soils of central China

The effect of several organic acids on phosphate adsorption by acidic soils in subtropical zone of central China was studied. Results showed: (1) citrate and oxalate remarkably reduced the amount of phosphate adsorption, but tartrate, benzoate and acetate had only a very slight influence on phosphate adsorption; (2) the ability of citrate in reducing phosphate adsorption was greater than that of oxalate, moreover, the reduction percentage was dependent on the concentration of organic ligands in the solution; (3) the effect of organic acids on phosphate adsorption was related to the pH value of organic acid solution. The minimum reduction in adsorption of phosphate was present at a specific pH value of organic acid solution which ranged from 2 to 10; (4) a minimum reduction of phosphate adsorption occurred when phosphate was added to the soils before organic acid, whereas a maximum occurred when organic acid was introduced before the addition of phosphate. Meanwhile, the treatment for the mixture of two organic acids resulted in more reduction in phosphate adsorption than each of the organic acids and less than the total of them. Based on these observations, we suggested that the competition between phosphate and organic acids relied on their relatively affinity to soil mineral surface at different conditions.

[Identification of the barley chromosome in wheat by GISH and RFLP]

The barley chromosome in wheat was identified by genomic in situ hybridization (GISH) in which biotin labelled total genomic DNA of barley Betzes was used as probe and the unlabelled total DNA of common wheat Chinese Spring (CS) as blocking DNA. A series of wheat materials were tested as follows: two disomic alien substitution and monosomic alien addition lines, 2n = 43; two monosomic alien substitution lines, 2n = 42; seven disomic alien substitution lines, 2n = 42. RFLP probe psr131 on the short arm of the homologous group 2 was used to analyze the barley chromosome in wheat. The result indicated that there was a same band in barley Betzes and substitution line A5. The chromosome 2A of A5 was substituted by the chromosome 2H of barley. These materials will be useful in transferring the valuable genes in the chromosome 2H to wheat.

[A study on mechanism of skin penetration by cercaria of S. japonicum and screening of preventive drugs]

Mice pretreated with PG cyclo-oxygenase inhibitor aspirin, at 300 mg/kg/d x 5, and ibuprofen, at 100 mg/kg/d x 5 orally and 20 mg/kg/d x 3 intraperitoneally revealed moderate chemoprophylactic effects and the reduction of the penetration of worms by 23% when compared to controls. Daily oral administration of aspirin, at 300 mg/kg for 15 days the worms reduction increased to 41.7%. In estimation of PGE1 in cercariae of S. japonicum by radioimmunoassay, the PGE1 was 49 pg/100 cercariae. In normal mouse skin PGE1 has been measured to amount to 3105 +/- 691.7 pg/10 mg on average. In cercarial penetrated mouse skin, 1.5 hours after exposure the PGE1 assessed in 100 and 250 cercariae in the infected skin were 5506 +/- 1127.1 and 12085 +/- 2622.9 pg/10 mg respectively, which were significantly higher than that of the non-penetrated skin. These studies in conjunction with our previous work indicate that: 1.PGs, similar to S. mansoni, were probably necessary for cercarial penetration. 2.PG inhibitors could reduce cercarial penetration. Receptors antagonist etc. e.g. diphenhydramine, chlorpheniramine, atropine, practolol could not reduce cercarial penetration, but praziquantel in the pretreated mice could reduce cercarial penetration significantly. e.g. 400 mg/kg orally 2 hours prior to affection of cercariae about 100% reduction of the penetration, but if pretreated with praziquantel, 4, 8, 24, 36 hours prior to the affection the reduction penetration decreased to 51.7, 46.1, 9.4, 8.9% respectively.