Safflower yellow and its main component hydroxysafflor yellow A alleviate hyperleptinemia in diet-induced obesity mice through a dual inhibition of the GIP-GIPR signaling axis.

Glucose-dependent insulinotropic polypeptide (GIP) is a gastrointestinal hormone secreted by K cells in the small intestine and is considered an obesity-promoting factor. In this study, we systematically investigated the anti-obesity effects of intragastric safflower yellow (SY)/hydroxysafflor yellow A (HSYA) and the underlying mechanism for the first time. Our results showed that intragastric SY/HSYA, rather than an intraperitoneal injection, notably decreased serum GIP levels and GIP staining in the small intestine in diet-induced obese (DIO) mice. Moreover, intragastric SY/HSYA was also first found to significantly suppress GIP receptor (GIPR) signaling in both the hypothalamus and subcutaneous White adipose tissue. Our study is the first to show that intragastric SY/HSYA obviously reduced food intake and body weight gain in leptin sensitivity experiments and decreased serum leptin levels in DIO mice. Further experiments demonstrated that SY treatment also significantly reduced leptin levels, whereas the inhibitory effect of SY on leptin levels was reversed by activating GIPR in 3 T3-L1 adipocytes. In addition, intragastric SY/HSYA had already significantly reduced serum GIP levels and GIPR expression before the serum leptin levels were notably changed in high-fat-diet-fed mice. These findings suggested that intragastric SY/HSYA may alleviate diet-induced obesity in mice by ameliorating hyperleptinemia via dual inhibition of the GIP-GIPR axis.

Metabolic Profile and Echocardiographic Evaluation in Adults with Growth Hormone Deficiency.

Adult growth hormone deficiency (AGHD) is associated with increased cardiovascular risks. The primary endpoint of this retrospective cohort study was to compare metabolic profile and echocardiographic parameters in childhood-onset (CO) and adulthood-onset (AO) AGHD patients. 26 patients with CO AGHD (19 males, 26.8±8.5 years) and 41 patients with AO AGHD (23 males, 35.1±6.8 years) were included. The standard deviation score of insulin-like growth factor-1 (IGF-1 SDS), metabolic profile, liver sonography and echocardiographic parameters were compared. The IGF-1 SDS were significantly lower in CO AGHD patients (p<0.05). AO AGHD patients showed much profound glycolipid aberrations, elevated C-reactive protein levels (p=0.012), and proportionally higher prevalence of non-alcoholic fatty liver disease (95.2% vs.8.3%, p<0.001). In all subjects, IGF-1 SDS was negatively related to low-density lipoprotein cholesterol, and positively related to total cholesterol and lipoprotein a (Lpa). There were significant differences between the two group with regard to the correlations between IGF-1 SDS and high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, LPa, uric acid and creatinine (all p for interaction<0.05). CO AGHD patients exhibited smaller heart, but similar ventricular ejection fraction compared to AO AGHD patients. AGHD may be a group of heterogenous entity based on the onset ages of disease. AO patients had prominent metabolic disorders, while CO patients had smaller heart but similar cardiac performance. Whether growth hormone replacement therapy will equally benefit both CO and AO AGHD patients needs further investigations.

Reduced Bone Mineral Density in Middle-Aged Male Patients with Adult Growth Hormone Deficiency.

The aim of the work was to investigate the bone mineral density (BMD) in middle-aged male patients with both childhood-onset (CO) and adulthood-onset (AO) adult growth hormone deficiency (AGHD). In this retrospective cross-sectional study in a major medical center in China, dual X-ray absorptiometry was performed in 50 male AGHD patients (average age was 35.2±9.8 years) and 50 age- and BMI-matched non-athletic healthy men. BMD was compared between AGHD patients and controls. Compared with healthy controls, AGHD group had significantly decreased IGF-1 (p1<0.001) and IGF-1 SDS (p1<0.001). Serum testosterone levels were significantly lower in AGHD patients (p1<0.001), mainly in AO AGHD patients (p3<0.001). The BMD of the femoral neck, trochanter, femoral shaft, total hip, and lumbar spine were significantly lower in all AGHD patients compared with healthy controls (all p1<0.05), especially in CO AGHD patients (all p2<0.05). Multiple stepwise linear regression indicated AGHD was negatively correlated with BMD at each site (ß<0, p<0.05). Additionally, serum testosterone level was an independent influencing factor of BMD of the femoral neck (ß=0.256, p=0.018) and lumbar spine (ß=0.219, p=0.040). BMD was significantly reduced in AGHD patients, especially in CO AGHD patients. Our data suggested that the status of growth hormone deficiency and testosterone level were important for maintaining of bone mineral density in middle-aged male patients with AGHD.

The Antiobesity Effect and Safety of GLP-1 Receptor Agonist in Overweight/Obese Patients Without Diabetes: A Systematic Review and Meta-Analysis.

Aim To determine the antiobesity effect and safety of glucagon-like peptide-1 receptor agonist (GLP-1RA) including liraglutide, exenatide and semaglutide treatment in overweight/obese patients without diabetes. The random-effect model was used to pool data extracted from included literatures. The weighted mean difference (WMD), odds ratio and 95% confidence interval (CI) were used to present the meta-analysis results (PROSPERO registration number: CRD 42020173199). The sources of intertrial heterogeneity, bias and the robustness of results were evaluated by subgroup analysis, sensitivity analysis and regression analysis, respectively. A total of 24 RCTs were recruited in the present analysis which included 5867 patients. The results showed that the treatment of overweight/obese patients without diabetes with GLP-1RAs including liraglutide, exenatide and semaglutide significantly achieved greater weight loss than placebo [WMD=-5.39, 95% CI (-6.82, -3.96)] and metformin [WMD=-5.46, 95% CI (-5.87, -5.05)]. The subgroup analysis showed that semaglutide displayed the most obvious antiobesity effect in terms of weight loss, the reduction of body mass index (BMI) and waist circumference (WC). However, GLP-1RAs treatments had more gastrointestinal adverse events (such as nausea and vomiting) than placebo and Met. The subgroup analysis also represented that semaglutide displayed the lowest risk of gastrointestinal adverse events among three kinds of GLP-1RAs. Our meta-analysis demonstrated that GLP-1RA had a superior antiobesity effect than placebo/Met in overweight/obese patients without diabetes in terms of body weight, BMI, and WC, especially for semaglutide, which had more obvious antiobesity effect and lower GI adverse events than liraglutide and exenatide.

A novel anti-obesity mechanism for liraglutide by improving adipose tissue leptin resistance in high-fat diet-fed obese mice.

Liraglutide has been approved for the treatment of obesity in the past few years. Both oxidative stress and leptin resistance are the critical drivers of obesity. The present study investigated the mechanism of liraglutide protection against obesity by ameliorating leptin resistance and oxidative stress. Male C57BL/6J mice were fed a high-fat diet (HFD) and subcutaneously injected with 200 µg/kg/d liraglutide for 20 weeks. Body weight, fat mass, serum levels of leptin, insulin, and superoxide dismutase (SOD) activities were measured. In addition, glucose and insulin tolerance tests were performed. The expressions of leptin, its signaling genes, and antioxidant enzymes were detected using RT-qPCR and western blot methods in liver and white adipose tissue (WAT) of mice. The results depicted that liraglutide treatment significantly slowed weight gain of body, reduced the fat mass, ameliorated glucose and lipid metabolism, and hepatic steatosis in HFD-fed obese mice. Further study demonstrated that liraglutide treatment resulted in decreased serum levels and the transcript levels of leptin as well as leptin signaling inhibitory regulators. However, it increased leptin receptor expression and the phosphorylation of signal transducer and activator of transcription 3 (p-STAT3) in WAT (p < 0.05). In addition, the antioxidant enzyme expression was elevated in both liver and WAT of liraglutide-treated mice (p < 0.05). In conclusion, liraglutide conspicuously prevented obesity and ameliorated glucose and lipid metabolism in obese mice through a novel mechanism that improves peripheral leptin resistance in WAT and enhance the antioxidant enzyme expression in both liver and WAT.

Protective Effects of Anthocyanins from Coreopsis tinctoria against Oxidative Stress Induced by Hydrogen Peroxide in MIN6 Cells.

Anthocyanins (AC) from Coreopsis tinctoria possesses strong antioxidant properties, while the effects of AC on cells damage induced by reactive oxygen species (ROS) in diabetes mellitus diseases progression have not been reported. The present study was carried out to evaluate the protective property of AC against cellular oxidative stress with an experimental model, H2 O2 -exposed MIN6 cells. AC could reverse the decrease of cell viability induced by H2 O2 and efficiently suppressed cellular ROS production and cell apoptosis. In addition, Real-time PCR and Western blot analyses indicated that AC could protect MIN6 cells against oxidative injury through increasing the translocation of Nrf2 into nuclear, decreasing the phosphorylation level of p38 and up-regulating the protein expression of antioxidant enzyme (SOD1, SOD2 and CAT). Thus, this study provides evidence to support the beneficial effect of AC in inhibiting MIN6 cells from H2 O2 -induced oxidative injury.

The distinct hepatic metabolic profile and relation with impaired liver function in congenital isolated growth hormone-deficient rats.

Objective: Patients with growth hormone deficiency (GHD) with inadequate growth hormone levels are often correlated with nonalcoholic fatty liver disease (NAFLD). However, the potential mechanism of how GHD influences liver function remains obscure. In the present study, we aim to perform hepatic metabolomics in Lewis dwarf rats, which were the standard congenital isolated GH-deficient rat, to evaluate the characterizations of hepatic metabolic profiles and explore their relations with liver functions. Methods: Lewis dwarf homozygous (dw/dw) rats at 37 weeks (five females and five males), and Lewis dwarf heterozygous (dw/+) rats at 37 weeks (five females and five males) were analyzed in our study. Body lengths and weights, liver weights, serum alanine transaminase (ALT), and serum aspartate transaminase (AST) were measured. ELISA and RT-qPCR were used to assess IGF-1 levels in serum and liver, respectively. The non-targeted metabolomics was performed in the livers of dw/+ and dw/dw rats. Differential metabolites were selected according to the coefficient of variation (CV), variable importance in the projection (VIP) > 1, and P < 0.05. Hierarchical clustering of differential metabolites was conducted, and the KEGG database was used for metabolic pathway analysis. Results: The body weights, body lengths, liver weights, and IGF-1 levels in the serum and liver of dw/dw rats were significantly decreased compared with dw/+ rats. Dw/dw rats exhibited more obvious hepatic steatosis accompanied by higher serum ALT and AST levels. Hepatic metabolomics showed that a total of 88 differential metabolites in positive ion mode, and 51 metabolites in negative ion mode were identified. Among them, lysophosphatidylcholine (LPC) 16:2, LPC 18:3, LPC 22:6, fatty acid esters of hydroxy fatty acids (FAHFA)18:1 were significantly decreased, while palmitoyl acid, dehydrocholic acid, and 7-ketolithocholic acid were significantly increased in dw/dw rats compared with dw/+ rats. These seven differential metabolites were significantly associated with phenotypes of rats. Finally, KEGG pathway analysis showed that the arginine and proline metabolism pathway and bile secretion pathway were mainly clustered. Conclusion: Lewis dw/dw rats with congenital isolated growth hormone deficiency (IGHD) showed liver steatosis and abnormal liver function, which could be potentially associated with the distinctive hepatic metabolic profiles.

Bone mineral density in adults growth hormone deficiency with different ages of onset: a real-world retrospective study.

PURPOSE: Bone mineral density (BMD) impairment is one of the critical factors for long-term quality of life in adults growth hormone deficiency (AGHD). This study aims to investigate the annual changes in BMD in AGHD patients with different ages of onset and to identify predicting factors that influence BMD. METHODS: AGHD patients (n = 160) with available data for 4 years follow-up from a major tertiary medical center in China were retrospectively included (110 [68.8%] childhood-onset, 119 [74.4%] male). BMD of the axial bone (including total hip, neck of femur, and L1-4) derived from dual X-ray absorptiometry and final height were investigated at the first visit, 12 months, 24 months, 36 months, and 48 months thereafter. Low BMD was defined as Z-score ≤ -2. RESULTS: The prevalence of low BMD was 30.0% at baseline and 12.5% at 4 years of follow-up. The CO AGHD group presented a significantly lower BMD than the AO AGHD group at the baseline (P = 0.009). In contrast, the CO AGHD group had significantly greater median annual BMD change than the AO AGHD group (0.044 vs. -0.0003 g/cm2/year in L1-4, P < 0.001), indicating a significant difference in the overall BMD trend between CO and AO groups. Childhood-onset (odds ratio [OR] 0.326, P = 0.012), low serum testosterone (OR 0.847; P = 0.004) and FT4 (OR 0.595; P = 0.039) level were independent risk factors for BMD loss. CONCLUSION: The annual changes of BMD show a different pattern in AGHD patients with varying ages of onset. Patients with CO AGHD have a lower bone mass, and in general, appropriate replacement therapy is necessary for long-term bone health in AGHD patients.

ZmDST44 Gene Is a Positive Regulator in Plant Drought Stress Tolerance.

Improving drought tolerance in plants is essential for increasing crop yields under water-limited conditions. In this study, we investigated the functional role of the maize gene ZmDST44, which is targeted by the miRNA ZmmiR139. Our results indicate that ZmmiR139 regulates ZmDST44 by cleaving its mRNA, as confirmed by inverse expression patterns and 5'-RACE analysis. Overexpression of ZmDST44 in Arabidopsis, rice, and maize resulted in significant enhancements in drought tolerance. Transgenic plants exhibited reduced malondialdehyde (MDA) levels, increased proline accumulation, and upregulation of drought-responsive genes compared to wild-type plants. Transgenic Arabidopsis and rice showed improved drought resistance and higher post-drought recovery rates, and transgenic maize displayed lower sensitivity to drought stress. These findings suggest that ZmDST44 acts as a positive regulator of drought tolerance across different plant species and holds promise for developing drought-resistant crops through genetic engineering.

New Insights into Alzheimer's Disease: Novel Pathogenesis, Drug Target and Delivery.

Alzheimer's disease (AD), the most common type of dementia, is characterized by senile plaques composed of amyloid ß protein (Aß) and neurofilament tangles derived from the hyperphosphorylation of tau protein. However, the developed medicines targeting Aß and tau have not obtained ideal clinical efficacy, which raises a challenge to the hypothesis that AD is Aß cascade-induced. A critical problem of AD pathogenesis is which endogenous factor induces Aß aggregation and tau phosphorylation. Recently, age-associated endogenous formaldehyde has been suggested to be a direct trigger for Aß- and tau-related pathology. Another key issue is whether or not AD drugs are successfully delivered to the damaged neurons. Both the blood-brain barrier (BBB) and extracellular space (ECS) are the barriers for drug delivery. Unexpectedly, Aß-related SP deposition in ECS slows down or stops interstitial fluid drainage in AD, which is the direct reason for drug delivery failure. Here, we propose a new pathogenesis and perspectives on the direction of AD drug development and drug delivery: (1) aging-related formaldehyde is a direct trigger for Aß assembly and tau hyperphosphorylation, and the new target for AD therapy is formaldehyde; (2) nano-packaging and physical therapy may be the promising strategy for increasing BBB permeability and accelerating interstitial fluid drainage.

Identifying Ferroptosis-Related Genes Associated with Weight Loss Outcomes and Regulation of Adipocyte Microenvironment.

SCOPE: The study is about the influence of ferroptosis-related genes combined with the immune microenvironment exerted on weight control outcomes and systematic analysis. METHODS AND RESULTS: Subcutaneous adipose tissue (sWAT) samples from 11 subjects with good outcome and 10 subjects with poor outcome in weight management are obtained from the Gene Expression Omnibus database. The results are validated in vivo in animal models with different weight loss outcomes. The CIBERSORT algorithm is used to evaluate the differences in immune cell infiltration in each sample. Patients with poor outcome have higher levels of ferroptosis in the adipose tissue. Remarkable differences in cytokine production, nuclear factor kappa-B(NF-κB) transcription factor activity, leukocyte migration involved in the inflammatory response, and other biological processes are also observed compared to that in the well-controlled group. Aldo-keto reductase family 1-member C1(AKR1C1), nuclear receptor coactivator 4(NCOA4), and glutamate-cysteine ligase catalytic subunit(GCLC) are identified as core predictive markers and their expression patterns are confirmed in animal models. CONCLUSIONS: Ferroptosis and its mediated inflammation play an important role in long-term weight control, and analyses of the role of ferroptosis-related genes(FRGs) in weight control may provide new potential therapeutic targets for long-term weight control. Anti-inflammatory diets that mitigate inflammatory responses and affect ferroptosis may be considered in the future to improve weight control.

Intragastric Safflower Yellow Alleviates HFD Induced Metabolic Dysfunction-Associated Fatty Liver Disease in Mice through Regulating Gut Microbiota and Liver Endoplasmic Reticulum Stress.

The gut microbiota was reported to play a significant role in the progression of the metabolic associated fatty liver disease (MAFLD). Our recent study suggested that gastrointestinal tract and liver were important targets mediating the anti-obesity effects of intragastric safflower yellow (SY). Therefore, our present study aims to investigate the effect of intragastric SY on MAFLD and possible mechanism. DIO mice were treated with 125 mg/kg/d SY for 12 weeks by gavage. We found intragastric SY significantly slowed weight gain of body, reduced the food intake and liver weight, improved hepatic steatosis, liver function and glucose metabolism in DIO mice. The comparison between OGTT and IPGTT illustrated OGTT produced a better improvement of glucose tolerance after SY treatment. We also found intragastric SY significantly increased the energy expenditure and locomotor activity of DIO mice. SY obviously decreased the expression of lipogenesis-associated and ERS-related genes in liver of DIO mice and PA-induced MAFLD hepatocyte model. Gut microbiota analysis demonstrated intragastric SY apparently changed the diversity and composition of gut microbiota of DIO mice. Further function prediction analysis indicated that gut microbiotas in SY-treated mice was positively related with energy metabolism, lipid metabolism and endocrine system. Intragastric SY has a significant therapeutic effect on MAFLD, which is mediated partly by modulating gut microbiota and improving liver ERS.

Serum metabolomics profiling of improved metabolic syndrome is characterized by decreased pro-inflammatory biomarkers: A longitudinal study in Chinese male adults.

Metabolic syndrome (MetS) is a serious global health concern. The objective of this study is to dynamically investigate the changes of metabolic profiles and metabolites in Chinese male MetS subjects after an 18 months diet and exercise intervention. Fifty male MetS patients defined according to International Diabetes Federation 2005 guidelines were subjected to diet and exercise counseling for 18 months. Serum samples were taken at baseline, 12 months, and 18 months, respectively, for clinical evaluation and metabolomics analyses. Diet and exercise intervention for 18 months achieved significant improvements in the metabolic profiles of all participants. Nineteen subjects (38.0%) exhibited MetS remission at the end of the study. A total of 812 relative features were characterized and 61 were successfully identified. Furthermore, 17 differential metabolites were of significance at both time points (baseline-12 months, baseline-18 months) and presented nonlinear trends through time. Eight metabolites (47.1%) were predominantly converged to inflammation and oxidative stress. Pro-inflammatory biomarkers were remarkably decreased after 18 months of intervention, and prostaglandin E2, neuroprotectin D1, and taxiphyllin in combination were firstly found to demonstrate a fair discriminative power (area under curve = 0.911) to predict the improvement of MetS undergone diet and exercise intervention. The significant shift of metabolomic profiling after 18 months of lifestyle counseling provide a novel insight and reveal that earlier inflammation control may be of potential benefit in MetS management.

Intragastric safflower yellow and its main component HSYA improve leptin sensitivity before body weight change in diet-induced obese mice.

Our previous studies found that safflower yellow (SY) and its main component hydroxysafflor yellow A (HSYA) could alleviate obesity and improve leptin resistance in high-fat diet (HFD) induced obese mice. Therefore, our present study aimed to investigate whether the above effect of SY/HSYA was a direct effect or follow-up effect of weight loss and whether leptin was essential for the anti-obesity effect of SY/HSYA or not. HFD-induced obese mice were treated with SY or HSYA for 4 weeks, while ob/ob mice were treated with SY for 10 weeks. Body weight, food intake, fat mass, and serum leptin levels were measured. The leptin sensitivity experiment was conducted in HFD-induced obese mice. The expressions of leptin and its signaling-related genes were detected by RT-qPCR and Western blot methods. SY/HSYA treatment had no effect on food intake, energy expenditure, body weight, fat mass, and serum leptin levels in HFD-induced obese mice. However, the leptin sensitivity experiment showed that the food intake decreased by 18.4% in the HFD-SY group and the body weight gain decreased by 104.6% in the HFD-HSYA group, respectively (both P < 0.05). Furthermore, the expressions of leptin and leptin signaling inhibitory regulators were significantly decreased, while the phosphorylation of signal transducer and activator of transcription 3 (p-STAT3) were notably increased in WAT of HFD-induced obese mice, fully differentiated 3T3-L1 adipocytes after SY/HSYA intervention (all P < 0.05). Interestingly, SY treatment was ineffective on body weight, fat mass, and glucose metabolism in leptin-deficient ob/ob mice. SY/HSYA administration could firstly improve peripheral leptin resistance in adipose tissue of HFD-induced obese mice before their body weight was significantly changed, and leptin was essential for the anti-obesity effect of SY.

Distinct AMPK-Mediated FAS/HSL Pathway Is Implicated in the Alleviating Effect of Nuciferine on Obesity and Hepatic Steatosis in HFD-Fed Mice.

Nuciferine (Nuci), the main aporphine alkaloid component in lotus leaf, was reported to reduce lipid accumulation in vitro. Herein we investigated whether Nuci prevents obesity in high fat diet (HFD)-fed mice and the underlying mechanism in liver/HepG2 hepatocytes and epididymal white adipose tissue (eWAT) /adipocytes. Male C57BL/6J mice were fed with HFD supplemented with Nuci (0.10%) for 12 weeks. We found that Nuci significantly reduced body weight and fat mass, improved glycolipid profiles, and enhanced energy expenditure in HFD-fed mice. Nuci also ameliorated hepatic steatosis and decreased the size of adipocytes. Furthermore, Nuci remarkably promoted the phosphorylation of AMPK, suppressed lipogenesis (SREBP1, FAS, ACC), promoted lipolysis (HSL, ATGL), and increased the expressions of adipokines (FGF21, ZAG) in liver and eWAT. Besides, fatty acid oxidation in liver and thermogenesis in eWAT were also activated by Nuci. Similar results were further observed at cellular level, and these beneficial effects of Nuci in cells were abolished by an effective AMPK inhibitor compound C. In conclusion, Nuci supplementation prevented HFD-induced obesity, attenuated hepatic steatosis, and reduced lipid accumulation in liver/hepatocytes and eWAT/adipocytes through regulating AMPK-mediated FAS/HSL pathway. Our findings provide novel insight into the clinical application of Nuci in treating obesity and related complications.

25-hydroxyvitamin D levels are inversely related to metabolic syndrome risk profile in northern Chinese subjects without vitamin D supplementation.

BACKGROUND: The comparatively low 25 hydroxyvitamin D [25(OH)D] levels have been reported in patients with metabolic syndrome (MetS). Herein we investigated the cross-sectional and longitudinal relationships between serum 25(OH)D levels and MetS risk profile in northern middle-aged Chinese subjects without vitamin D supplementation. METHODS: A cohort of 211 participants including 151 MetS patients and 60 controls at 20-69 years of age were enrolled from suburban Beijing, China. The recruited MetS patients were subjected to diet and exercise counselling for 1-year. All subjects at baseline and MetS patients after intervention underwent clinical evaluations. RESULTS: Serum 25(OH)D levels were significantly decreased in MetS patients. 25(OH)D levels were inversely related to MetS score, fasting blood glucose (FBG) and triglyceride-glucose index (TyG) after adjusting for cofounders (all P < 0.05). Participants in the lowest tertile of 25(OH)D levels had increased odds for MetS (P = 0.045), elevated FBG (P = 0.004) in all subjects, and one MetS score gain in MetS patients (P = 0.005). Longitudinally, the metabolic statuses as well as 25(OH)D levels of MetS patients were significantly improved (all P < 0.05), and the increase of 25(OH)D levels were inversely related to MetS scores, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), FBG, and TyG, while positively related to high-density lipoprotein cholesterol (HDL-C) after adjusting for confounders. CONCLUSIONS: 25(OH)D levels were significantly decreased in MetS patients, and it was negatively associated with metabolic dysfunctions at baseline and 1-year after. Metabolic aberrations of MetS patients were significantly ameliorated with 1-year follow-up counselling accompanying by notably elevated 25(OH)D levels.

Nuciferine Inhibited the Differentiation and Lipid Accumulation of 3T3-L1 Preadipocytes by Regulating the Expression of Lipogenic Genes and Adipokines.

Purposes: Nuciferine, a main aporphine alkaloid component found in lotus leaf (Nelumbo nucifera), has been demonstrated to possess the property of reducing fat mass and alleviating dyslipidemia in vivo. The purpose of this study is to explore the effects of nuciferine on the proliferation and differentiation of 3T3-L1 cells and further investigate the possible underlying molecular mechanisms. Methods: 3T3-L1 preadipocytes were treated with 0∼20 µM nuciferine for 24∼120 h, the cell viability was assessed using CCK8. 3T3-L1 preadipocytes and human primary preadipocytes were then induced differentiation and the effects of nuciferine on the lipid metabolism in differentiating and fully differentiated adipocytes were observed by the methods of intracellular triglyceride (TG) assay, Oil Red O staining, RT-qPCR and western blot. Transient transfection and dual luciferase reporter gene methods were used to assess the effects of nuciferine on FAS promoter activities. Results: Nuciferine inhibited the proliferation of 3T3-L1 preadipocytes in a dose- and time-dependent manner. 20 µM nuciferine significantly attenuated lipid accumulation and reduced intracellular TG contents by 47.2, 59.9 and 55.4% on the third, sixth and ninth day of preadipocytes differentiation, respectively (all p < 0.05). Moreover, the mRNA levels of PPARγ, C/EBPα, C/EBPß, FAS, ACC, HSL and ATGL were notably decreased by 39.2∼92.5% in differentiating preadipocytes when treated with 5∼20 µM nuciferine (all p < 0.05). In fully differentiated adipocytes treated with 20 µM nuciferine for 48 h, the mRNA levels of FAS, ACC and SREBP1 were remarkably downregulated by 22.6∼45.2% compared with the controls (0 µM) (all p < 0.05), whereas the expression of adipokines FGF21 and ZAG were notably promoted by nuciferine. Similarly, in fully differentiated human primary adipocytes, the mRNA levels of FAS, ACC, SREBP1 were decreased and the expression of FGF21 and ZAG were elevated after treated with nuciferine (all p < 0.05). Further mechanism studies showed that 2.5∼20 µM nuciferine significantly decreased FAS promoter activities in 3T3-L1 preadipocytes. Conclusion: Nuciferine inhibited the proliferation and differentiation of 3T3-L1 preadipocytes. The inhibitory effects of nuciferine on adipogenesis might be due to the downregulation of PPARγ, C/EBPα and C/EBPß, which led to the reduction of intracellular lipid accumulation in 3T3-L1 cells and by downregulating the expression of critical lipogenic enzymes, especially of FAS, which was achieved by inhibiting the FAS promoter activities. Besides, nuciferine promoted the expression of adipokines in fully differentiated adipocytes.