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1.
Nat Commun ; 15(1): 3850, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38719864

ABSTRACT

The K+ uptake system KtrAB is essential for bacterial survival in low K+ environments. The activity of KtrAB is regulated by nucleotides and Na+. Previous studies proposed a putative gating mechanism of KtrB regulated by KtrA upon binding to ATP or ADP. However, how Na+ activates KtrAB and the Na+ binding site remain unknown. Here we present the cryo-EM structures of ATP- and ADP-bound KtrAB from Bacillus subtilis (BsKtrAB) both solved at 2.8 Å. A cryo-EM density at the intra-dimer interface of ATP-KtrA was identified as Na+, as supported by X-ray crystallography and ICP-MS. Thermostability assays and functional studies demonstrated that Na+ binding stabilizes the ATP-bound BsKtrAB complex and enhances its K+ flux activity. Comparing ATP- and ADP-BsKtrAB structures suggests that BsKtrB Arg417 and Phe91 serve as a channel gate. The synergism of ATP and Na+ in activating BsKtrAB is likely applicable to Na+-activated K+ channels in central nervous system.


Subject(s)
Adenosine Diphosphate , Adenosine Triphosphate , Bacillus subtilis , Bacterial Proteins , Potassium , Sodium , Adenosine Triphosphate/metabolism , Bacillus subtilis/metabolism , Sodium/metabolism , Bacterial Proteins/metabolism , Bacterial Proteins/chemistry , Potassium/metabolism , Crystallography, X-Ray , Adenosine Diphosphate/metabolism , Cryoelectron Microscopy , Binding Sites , Cation Transport Proteins/metabolism , Cation Transport Proteins/chemistry , Models, Molecular , Protein Binding
2.
Am J Med Sci ; 2024 Mar 11.
Article in English | MEDLINE | ID: mdl-38479487

ABSTRACT

BACKGROUND: This study aimed to investigate whether physical activity (PA) is associated with a lower risk of subsequently developing chronic obstructive pulmonary disease (COPD). METHODS: We conducted this population-based longitudinal follow-up study in a community in Taiwan. This study recruited 61,446 subjects who had participated in the Keelung Community-based Integrated Screening Program (KCIS) between 2005 and 2012. During their participation in KCIS, they were provided with structured questionnaires to collect their baseline characteristics, including weekly PA time. After excluding subjects diagnosed with COPD before they joined KCIS and/or who provided incomplete lifestyle data, 59,457 subjects remained, and were classified into three groups based on their weekly PA time: i.e., as NPA (no regular PA), LPA (low PA, <90 min/week) and HPA (high PA, ≥90 min/week). The primary outcome was a new diagnosis of COPD, followed up until the end of 2015 or their death. Cox proportional-hazard regression was used to assess the impact of PA on the risk of COPD. RESULTS: The risk of COPD was more than 20% lower in the LPA and HPA groups than in the NPA group. Specifically, the adjusted hazard ratio for the risk of COPD was 0.72 in the LPA group (95% CI, 0.61-0.85, p < 0.001) and 0.79 in the HPA group (95% CI, 0.69-0.90, p < 0.001). CONCLUSIONS: Our research uncovered an inverse relationship between PA and COPD. The findings suggest that PA might be useful as a strategy for the primary prevention of COPD.

3.
Sleep Breath ; 27(5): 2069-2076, 2023 10.
Article in English | MEDLINE | ID: mdl-36856923

ABSTRACT

PURPOSE: Ferroptosis is reported to be involved in the chronic intermittent hypoxia (CIH)-related liver damage in vivo. Nuclear factor E2-related factor 2 (Nrf2) has an essential role in the regulation of ferroptosis. This study tested the hypothesis that intermittent hypoxia (IH) could lead to hepatocyte ferroptosis in vitro and the function of Nrf2 in IH-induced hepatocyte ferroptosis. METHODS: BRL-3A cells (rat liver cells) were exposed to normoxia or IH. The protocol of IH consisted of 32 cycles of 60-min hypoxic exposure with 30-min reoxygenation phase (nadir of 1% oxygen to peak of 20% oxygen). Ferroptosis was evaluated by cell viability, iron concentration, lipid reactive oxygen species (ROS), protein content of ferritin heavy chain (FTH1), and glutathione peroxidase 4 (GPX4). Both ferrostatin-1 (a ferroptosis inhibitor) and Nrf2 interfering RNA were applied to treat BRL-3A cells, respectively. RESULTS: IH exposure induced ferroptosis in BRL-3A cells with decreased cell viability and increased total iron content and lipid ROS levels. The protein contents of GPX4 and FTH1 in IH group were markedly lower than that in normoxic control. Ferroptosis inhibitor ferrostatin-1 alleviated IH-induced ferroptosis in BRL-3A cells. IH treatment enhanced expression of Nrf2, and Nrf2 knockdown augmented IH-induced ferroptosis in BRL-3A cells. CONCLUSIONS: The results revealed that Nrf2 played a protective role during IH-induced ferroptosis in BRL-3A cells. The finding provides a therapeutic target for obstructive sleep apnea-related liver injury.


Subject(s)
Ferroptosis , Animals , Rats , Hypoxia/metabolism , Iron/metabolism , Lipids , Liver/metabolism , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Oxygen/metabolism , Reactive Oxygen Species/metabolism
4.
Brain Behav ; 13(4): e2972, 2023 04.
Article in English | MEDLINE | ID: mdl-36938834

ABSTRACT

BACKGROUND: Alzheimer's disease (AD) is an irreversible, progressive brain disorder that impairs memory, thinking, language, and, eventually, the ability to carry out the simplest of tasks. Tau protein, the major component of neurofibrillary tangles, is considered a key mediator of AD pathogenesis. The association between obstructive sleep apnea (OSA) and circulating tau remains unclear. The aim of the present meta-analysis was to evaluate the relationship between OSA and circulating tau via quantitative analysis. METHODS: A systematic search of Pubmed, Embase, and Web of Science were performed. The mean values of circulating total tau (T-tau) and phosphorylated tau (P-tau) in OSA and control groups were extracted. Standardized mean difference (SMD) with 95% confidence interval (CI) was calculated by using a random-effect model or fixed-effect model. RESULTS: A total of seven studies comprising 233 controls and 306 OSA patients were included in this study. The meta-analysis showed that the circulating T-tau level was significantly higher in OSA patients than those in the control group (SMD = 1.319, 95% CI = 0.594 to 2.044, z = 3.56, p < .001). OSA patients also had significantly higher circulating P-tau level than control group (SMD = 0.343, 95% CI = 0.122 to 0.564, z = 3.04, p = .002). CONCLUSIONS: The present meta-analysis demonstrated that both circulating T-tau and P-tau levels were significantly increased in OSA subjects when compared with non-OSA subjects. Larger sample-size studies on the association between OSA and circulating tau are still required to further validate our results.


Subject(s)
Sleep Apnea, Obstructive , tau Proteins , Sleep Apnea, Obstructive/blood , tau Proteins/blood , tau Proteins/metabolism , Humans , Phosphorylation
5.
Osteoporos Int ; 34(1): 101-109, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36241848

ABSTRACT

This population-based longitudinal follow-up study showed a protective effect of tea consumption against osteoporosis, particularly among women and middle-aged people. High tea consumption was also associated with a reduced risk of hip fracture. INTRODUCTION: To investigate the association of tea consumption with the risks of osteoporosis and hip fracture. METHODS: This study used the Keelung Community-based Integrated Screening database and Taiwan's National Health Insurance Research Database. A total of 42,742 subjects aged 45 to 74 years were enrolled. Each was classified as no tea consumption, low tea consumption, and high tea consumption, according to the results of an eating habits questionnaire. The diagnosis of osteoporosis and hip fracture was based on BMD measured by dual-energy X-ray absorptiometry and the X-ray findings. The median follow-up time was 8.5 years. RESULTS: As compared with the no tea consumption group, the osteoporosis HRs for the low tea consumption and high tea consumption groups were 0.88 (95% confidence interval (CI) 0.80-0.96) and 0.87 (95% CI 0.80-0.94), respectively. Among those participants aged 59 or below, the osteoporosis HRs for low tea consumption and high tea consumption (vs. no tea consumption) were 0.85 (95% CI 0.74-0.96) and 0.79 (95% CI 0.69-0.90). The HRs of hip fracture for the low tea consumption and high tea consumption groups (vs. no tea consumption) were 0.85 (95% CI 0.67-1.08) and 0.69 (95% CI 0.55-0.86), respectively. CONCLUSION: Tea consumption was linked to a lower risk of osteoporosis, particularly among women and middle-aged people. High tea consumption was also associated with a reduced risk of hip fracture.


Subject(s)
Hip Fractures , Osteoporosis , Middle Aged , Female , Humans , Follow-Up Studies , Osteoporosis/epidemiology , Osteoporosis/etiology , Hip Fractures/epidemiology , Hip Fractures/etiology , Hip Fractures/prevention & control , Absorptiometry, Photon/methods , Risk , Bone Density , Risk Factors
6.
Pathol Res Pract ; 240: 154177, 2022 12.
Article in English | MEDLINE | ID: mdl-36327815

ABSTRACT

OBJECTIVES: To explore the Fibroblast-epithelial metabolic coupling among laryngeal cancers and its prognostic roles METHODS: We reviewed the clinical information of patients with laryngeal cancer in our department. Paraffin-embedded tissues from included patients were immune-stained with antibodies towards MCT4 and TOMM20 and evaluated for stromal and epithelial expression. Survival analysis and Cox regression analysis were applied to investigate the prognostic factor of laryngeal squamous cell carcinoma. TCGA database was used to validate our result. RESULTS: Stromal MCT4 and TOMM20 were both significantly associated with each other among laryngeal cancer tissues. High expression of both Stromal MCT4 and TOMM20 is related to poor prognosis in laryngeal cancer. Stromal MCT4 expression was an independent prognostic indicator for laryngeal cancer. Furthermore, cancer cell MCT4 expression has no relationship with the clinical characteristics of laryngeal cancer. CONCLUSIONS: Our results support that the phenomenon of metabolic symbiosis was exist in the laryngeal cancer tissue. In addition, TOMM20 and stromal MCT4 could be used as new therapeutic targets for laryngeal cancer.


Subject(s)
Head and Neck Neoplasms , Laryngeal Neoplasms , Humans , Monocarboxylic Acid Transporters/metabolism , Laryngeal Neoplasms/pathology , Muscle Proteins/metabolism , Prognosis , Fibroblasts/pathology , Head and Neck Neoplasms/pathology
7.
Front Physiol ; 13: 972407, 2022.
Article in English | MEDLINE | ID: mdl-36187780

ABSTRACT

Intermittent hypoxia (IH) is a prominent feature of obstructive sleep apnea (OSA) which is increasingly recognized as a key risk factor for liver injury. Circular RNAs (circRNAs) has been suggested to act as a regulator of multiple biological processes. However, there is no study evaluating circRNAs alterations and potential role of circRNAs in OSA-related liver injury. The present study aimed to investigate circRNA expression profiles in vitro model of IH-induced liver injury, as well as potential functional characterization of the differentially expressed circRNAs (DE circRNAs). BRL-3A cells were exposed to IH or normoxia. Cell apoptosis and cell viability were evaluated using flow cytometry and cell counting kit-8, respectively. The expression profile of circRNAs was depicted by circRNA sequencing. The selected circRNAs were verified by quantitative real-time PCR (qRT-PCR). Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) analyses were employed to predict DE circRNAs functions. The circRNA-miRNA-mRNA regulatory network was constructed. IH treatment caused cell injury in BRL-3A cells. 98 circRNAs were identified as being dysregulated in IH-treated BRL-3A cells. Among them, 58 were up-regulated and 40 were down-regulated. Go and KEGG analyses suggested that the DE circRNAs were predominantly enriched in the biological process such as positive regulation of NF-kappaB transcription factor activity and pathways such as circadian entrainment, Wnt signaling pathway, MAPK signaling pathway, and protein export. 3 up-regulated circRNAs and 3 down-regulated circRNAs with high number of back-splicing sites were chosen for qRT-PCR validation and were consistent with the sequencing data. CircRNA1056 and circRNA805 were predicted to interact with microRNAs that might thereby regulate downstream genes. The study characterized a profile of dysregulated circRNAs in IH-induced BRL-3A cell injury. DE circRNAs may play vital roles in the pathophysiology of IH-induced liver injury. Our findings provide preliminary support for further research in mechanisms and a new theory for the pathogenesis of OSA-related liver injury.

8.
J Agric Food Chem ; 70(38): 11944-11957, 2022 Sep 28.
Article in English | MEDLINE | ID: mdl-36120893

ABSTRACT

Dietary saponins have the potential to ameliorate atherosclerosis (AS). Gypenosides of Gynostemma pentaphyllum (GPs) have been used as functional foods to exhibit antiatherosclerotic activity. The present study aimed to explore the protective effect, underlying mechanism and active substances of GPs on AS in vivo and in vitro. Results demonstrated GPs administration reduced the serum concentrations of TC and LDL-C, upregulated the plasma HDL-C content, inhibited the secretion of ICAM-1, VCAM-1, and MCP-1, and alleviated vascular lesions in VitD3 plus high cholesterol diet-induced AS rats as well as reduced adhesion factors levels in ox-LDL-stimulated HUVECs, which was potentially associated with suppressing PCSK9/LOX-1 pathway. Further activity-guided phytochemical investigation of GPs led to the identification of five new dammarane-type glycosides (1-5) and ten known analogs (6-15). Bioassay evaluation showed compounds 1, 6, 7, 12, 13, and 14 observably reduced the expressions of PCSK9 and LOX-1, as well as the secretion of adhesion factors in injured HUVECs. Molecular docking experiments suggested that the active saponins of GPs might bind to the allosteric pocket of PCSK9 located at the catalytic and C-terminal domains, and 2α-OH-protopanaxadiol-type gypenosides might exert a higher affinity for an allosteric binding site on PCSK9 by hydrogen-bond interaction with ARG-458. These findings provide new insights into the potential nutraceutical application of GPs and their bioactive compounds in the prevention and discovery of novel therapeutic strategies for AS.


Subject(s)
Atherosclerosis , Saponins , Animals , Atherosclerosis/drug therapy , Atherosclerosis/genetics , Cholesterol, LDL , Gynostemma/chemistry , Hydrogen , Intercellular Adhesion Molecule-1 , Molecular Docking Simulation , Plant Extracts/chemistry , Plant Extracts/pharmacology , Proprotein Convertase 9 , Rats , Saponins/chemistry , Scavenger Receptors, Class E , Vascular Cell Adhesion Molecule-1
9.
Obes Facts ; 15(4): 621-628, 2022.
Article in English | MEDLINE | ID: mdl-35724630

ABSTRACT

INTRODUCTION: Adipose tissue deposited on the viscera is the main culprit in the development of insulin resistance (IR) and cardiometabolic diseases, whereas subcutaneous adipose tissue may have a protective role. This study aimed to propose a new predictive index - the visceral-fat area (VFA)-to-hip-circumference ratio (VHR) and explore its efficacy for prediction of IR in a Chinese population with type 2 diabetes mellitus. METHODS: A total of 643 patients with newly diagnosed diabetes were enrolled in this study. Body composition, anthropometrical, and biochemical measurements were performed. IR was defined as homeostatic model assessment of IR (HOMA-IR) > 2.69. The association between VHR and IR was analyzed. RESULTS: Regardless of gender, subjects in the IR group had higher VHR, body mass index (BMI), VFA, body fat percentage, systolic blood pressure, diastolic blood pressure (DBP), fasting blood glucose, fasting insulin, triglyceride (TG), uric acid (UA), homocysteine, and aminotransferases than those in the non-IR group. The other concomitant metabolic disorders were more common in the IR group. Further analysis showed that with the increase of VHR, the levels of HOMA-IR, BMI, VFA, DBP, TG, UA and the prevalence of nonalcoholic fatty-liver disease, hypertension, and hyperuricemia increased continuously (p trend <0.01). The linear trend test showed that VHR and IR remained closely correlated after adjusting for possible confounders (p trend <0.05). The receiver operating characteristic curve analysis showed that the area under the curve was 0.69, and the optimal cutoff of VHR was 0.89 (sensitivity 79.3%, specificity 61.5%). CONCLUSION: VHR was positively associated with IR regardless of gender, and it might be a reliable predictor for IR.


Subject(s)
Diabetes Mellitus, Type 2 , Insulin Resistance , Body Mass Index , China/epidemiology , Humans , Insulin , Intra-Abdominal Fat/metabolism , Triglycerides
10.
Front Med (Lausanne) ; 9: 854629, 2022.
Article in English | MEDLINE | ID: mdl-35620721

ABSTRACT

Aims: To investigate the long-term risk of age-related macular degeneration (AMD) in persons with osteoarthritis (OA). Methods: This retrospective cohort study first enrolled 71,609 subjects diagnosed with OA, and 236,169 without such a diagnosis between January 1, 2002 and December 31, 2005, from the Longitudinal Health Insurance Database 2005. All were aged 40-69. After excluding subjects who had pre-existing AMD and/or who had missing socioeconomic data, frequency matching by sex and age was performed. This resulted in there being 60,274 subjects in each of the final matched OA and non-OA groups. The study participants were followed up to the occurrence of AMD, death, or the end of 2011. We used Cox proportional-hazards regression to estimate the impact of OA on the risk of developing AMD, and performed subgroup analyses stratified by sex and age. Results: The median follow-up time was 8.9 years, with an interquartile range of 1.4 years. The incidence rate of AMD in the OA group was 2.77 per 1,000 person-years [95% confidence interval (CI), 2.62-2.92], and in the non-OA group, 2.06 per 1,000 person-years (95% CI, 1.94-2.19). The adjusted hazard ratio (HR) of AMD for the OA group was therefore 1.30 (95% CI, 1.20-1.41). In the subgroup analysis stratified by sex for the OA group, the adjusted HRs of AMD were 1.29 in the women's stratum and 1.31 in the men's. When stratified by age, the adjusted HRs of AMD for the younger (40-54 years) and older (55-69 years) strata were 1.28 and 1.31, respectively. Conclusions: Persons with OA have an increased risk of developing AMD, regardless of age and sex.

11.
Phytochemistry ; 194: 113005, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34798409

ABSTRACT

Seven undescribed dammarane-type saponins, gypenosides LXXXI-LXXXVII, together with four known compounds, were isolated from the whole herb of Gynostemma pentaphyllum. The chemical structures of these undescribed compounds were elucidated on the basis of physical and spectroscopic analysis and comparison with literature data. All the isolates were evaluated for their proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitory activities in HepG2 cells. Among them, gypenosides LXXXII-LXXXVII, gynosaponin II, IV and VI suppressed the expression of PCSK9 in LPDS-induced HepG2 cells at 20 µM; gypenosides LXXXII, LXXXV and LXXXVII showed inhibitory activities against PCSK9 at 10 µM; notably, gypenoside LXXXII still exhibited inhibitory activity against PCSK9 at 5 µM.


Subject(s)
Gynostemma/chemistry , PCSK9 Inhibitors/pharmacology , Saponins , Triterpenes/pharmacology , Hep G2 Cells , Humans , Proprotein Convertase 9 , Saponins/pharmacology , Dammaranes
12.
J Cell Mol Med ; 26(3): 750-763, 2022 02.
Article in English | MEDLINE | ID: mdl-34935260

ABSTRACT

Islet ß cell dedifferentiation is one of the most important mechanisms in the occurrence and development of diabetes. We studied the possible effects of chemokine stromal cell-derived factor-1 (SDF-1) in the dedifferentiation of islet ß cells. It was noted that the number of dedifferentiated islet ß cells and the expression of SDF-1 in pancreatic tissues significantly increased with diabetes. In islet ß cell experiments, inhibition of SDF-1 expression resulted in an increase in the number of dedifferentiated cells, while overexpression of SDF-1 resulted in a decrease. This seemed to be contradicted by the effect of diabetes on the expression of SDF-1 in pancreatic tissue, but it was concluded that this may be related to the loss of SDF-1 activity. SDF-1 binds to CXCR4 to form a complex, which activates and phosphorylates AKT, subsequently increases the expression of forkhead box O1 (FOXO1), and inhibits the dedifferentiation of islet ß cells. This suggests that SDF-1 may be a novel target in the treatment of diabetes.


Subject(s)
Hyperglycemia , Insulin-Secreting Cells , Islets of Langerhans , Chemokine CXCL12/metabolism , Forkhead Box Protein O1/genetics , Forkhead Box Protein O1/metabolism , Humans , Hyperglycemia/metabolism , Insulin-Secreting Cells/metabolism , Islets of Langerhans/metabolism , Pancreas/metabolism , Receptors, CXCR4/genetics , Receptors, CXCR4/metabolism , Signal Transduction
13.
BMJ Open ; 11(12): e056260, 2021 12 15.
Article in English | MEDLINE | ID: mdl-34911725

ABSTRACT

OBJECTIVES: To explore the prevalence and risk factors of metabolic-associated fatty liver disease (MAFLD) in Tianjin government employees of different genders. DESIGN: Cross-sectional study. SETTING: Health Management Center of Tianjin Union Medical Center. PARTICIPANTS: 16 924 government employees (59.6% male). MEASURES: Ultrasound liver examination was performed to determine whether there is fat accumulation in the organ. Participants' weight and height were measured, and body mass index (BMI) was calculated. RESULTS: The overall prevalence of MAFLD in this population was 40.76%. The rates were significantly higher in men (49.42%) than in women (27.97%). The prevalence of MAFLD was highest in men aged 40-49 years (54.04%) and women aged 60-69 years (43.44%). In all BMI groups, the prevalence was higher in men than that in women. In both genders, higher BMI was associated with the risk of MAFLD, especially for BMI ≥31.9 kg/m2. CONCLUSIONS: The prevalence of MAFLD in government employees in Tianjin was significantly higher than the average level in China. The prevalence varied by sex and age group, and those with high BMI were at the highest risk of developing MAFLD.


Subject(s)
Government Employees , Non-alcoholic Fatty Liver Disease , Adult , Aged , China/epidemiology , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Non-alcoholic Fatty Liver Disease/diagnosis , Prevalence
14.
Bioorg Chem ; 116: 105357, 2021 11.
Article in English | MEDLINE | ID: mdl-34562675

ABSTRACT

Gynostemma pentaphyllum (Thunb.) Makino (Cucurbitaceae family) is a perennial creeping plant with a common Chinese name of "south ginseng". To date, more than 250 individual saponins with dammarane-type skeleton have been isolated from G. pentaphyllum. The purpose of this study was the isolation and structural characterization of novel, minor gypenosides from G. pentaphyllum and evaluation of their Sirt1 agonist activity. Individual saponins from G. pentaphyllum were isolated and purified by a variety of chromatography techniques, and their structures were elucidated by means of various spectroscopic analysis and comparision with the reported data. Sirt1 enzyme activity detection kit was used to preliminarily evaluate the Sirt1 agonist activity of thirty three individual saponins purified from G. pentaphyllum. Fourteen new triterpenoid saponins named gypenoside CII-CXV (1-14) along with twenty six known compounds (15-40) were isolated from G. pentaphyllum. Thirty three of all the isolates were screened for Sirt1 agonist activity, and the results showed that three dammarane-type saponins (2, 18, 37) and one cucurbitane-type saponin 33 exhibited satisfactory Sirt1 agonist activity. These findings suggested that G. pentaphyllum was worthy of further investigation to find small molecule Sirt1 agonist and facilitate their utilization as "south ginseng".


Subject(s)
Gynostemma/chemistry , Saponins/pharmacology , Sirtuin 1/metabolism , Triterpenes/pharmacology , Dose-Response Relationship, Drug , Humans , Molecular Structure , Saponins/chemistry , Saponins/isolation & purification , Structure-Activity Relationship , Triterpenes/chemistry , Triterpenes/isolation & purification , Dammaranes
15.
Phytomedicine ; 91: 153688, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34380071

ABSTRACT

BACKGROUNDS: Atherosclerotic Cardiovascular Disease (ASCVD) is defined as ischemic or endothelial dysfunction-various inflammatory diseases, which is mainly caused by excessive low-density lipoprotein cholesterol (LDL-C) in circulating blood. Gynostemma pentaphyllum is a traditional Chinese medicine, and total Gypenosides are used for the treatment of hyperlipidemia and to reduce circulating proprotein convertase subtilisin/kexin type 9 (PCSK9) level. However, which gypenoside involved in the modulation of PCSK9 expression is still unknown. PURPOSE: This study aimed to discover effective PCSK9 inhibitors from Gypenosides in accordance with the 2019 ESC/EAS guidelines. METHODS: HPLC was employed to determine major six components of Gypenosides. The inhibitory activity on secreted PCSK9 in HepG2 of six major compounds from Gypenosides were screened by ELISA. The level of low-density lipoprotein (LDL) receptor (LDLR) was determined by Flow cytometry and Immunofluorescence. The expression levels of PCSK9, LDLR and Sterol-regulatory element binding proteins-2 (SREBP-2) were analyzed by qPCR and Western blot. DiI-LDL was added to evaluated LDL uptake into HepG2. RESULTS: The results suggested that the mRNA and protein levels of PCSK9 were down-regulated by Gypenoside LVI and the LDLR degradation in lysosomes system was inhibited, thereby leading to an increasing in LDL uptake into HepG2 cells. Furthermore, Gypenoside LVI decreased PCSK9 expression induced by stains. Altogether, Gypenoside LVI enhances LDL uptake into HepG2 cells by increased LDLR level on cell-surface and suppressed PCSK9 expression. CONCLUSION: This indicates that Gypenoside LVI can be used as a useful supplement for statins in the treatment of hypercholesterolemia. This is firstly reported that monomeric compound of G. pentaphyllum planted in Hunan province has the effect of increasing LDL-C uptake in hepatocytes via inhibiting PCSK9 expression.


Subject(s)
Gynostemma , Proprotein Convertase 9 , Receptors, LDL/metabolism , Cholesterol, LDL , Gynostemma/chemistry , Hep G2 Cells , Hepatocytes/drug effects , Humans , Plant Extracts/pharmacology , Proprotein Convertase 9/metabolism
16.
Bioorg Chem ; 111: 104843, 2021 06.
Article in English | MEDLINE | ID: mdl-33845383

ABSTRACT

Gynostemma pentaphyllum (Thunb.) Makino has a long history as food and diary supplement in China. At present, there are some products for hyperlipidemia in the market, including G. pentaphyllum tea, healthy wine and healthy food. In order to discover proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, fourteen new triterpenoid saponins named gypenoside LXXXVIII-CI (1-14) along with six known compounds (15-20) were isolated from G. pentaphyllum. Their structures were elucidated by means of various spectroscopic techniques. Eight isolates were evaluated the inhibitory effect on PCSK9 in HepG2 cells. The results showed that three dammarane-type glycosides (2, 3, 15) remarkably reduced PCSK9 expression at 10 µM concentration. These findings suggested that G. pentaphyllum was worthy of further investigation to find small molecule PCSK9 inhibitors and facilitate their utilization as functional food ingredients.


Subject(s)
Glycosides/pharmacology , Gynostemma/chemistry , Lipids/antagonists & inhibitors , PCSK9 Inhibitors , Triterpenes/pharmacology , Dose-Response Relationship, Drug , Glycosides/chemistry , Glycosides/isolation & purification , Hep G2 Cells , Humans , Molecular Structure , Proprotein Convertase 9/genetics , Proprotein Convertase 9/metabolism , Structure-Activity Relationship , Triterpenes/chemistry , Triterpenes/isolation & purification , Tumor Cells, Cultured , Dammaranes
17.
Phytochemistry ; 186: 112711, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33711738

ABSTRACT

Ten undescribed anthranoids, including three anthraquinone acetals as racemic mixtures, (±)-kenganthranol G-I, and seven prenylated anthranols, (±)-kenganthranol J-M and harunganol G-I, together with thirteen known compounds, were isolated from the stem bark of Harungana madagascariensis. The structures of (±)-kenganthranol G and (±)-kenganthranol J were confirmed by X-ray crystallography. (±)-Kenganthranol G was separated into (+)-kenganthranol G and (-)-kenganthranol G by chiral HPLC and their absolute configurations were established by electronic circular dichroism. (±)-Kenganthranol L displayed α-glucosidase inhibitory activity with an IC50 of 4.4 µM.


Subject(s)
Clusiaceae , Anthraquinones , Molecular Structure
18.
Scand J Gastroenterol ; 56(3): 312-320, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33535004

ABSTRACT

OBJECTIVE: Obesity and sarcopenia are known to be closely related to nonalcoholic fatty liver disease (NAFLD). We attempted to explore the combined influence of fat and muscle tissue on NAFLD by using visceral fat area to appendicular muscle mass ratio (VAR) as a novel parameter. MATERIAL AND METHODS: In this cross-sectional study, a total of 3255 adults (1399 men and 1856 women) coming for a health examination were enrolled. NAFLD was diagnosed using ultrasound and VAR was measured by bioelectrical impedance analyzer. RESULTS: The prevalence of NAFLD was 46.5% in men and 26.6% in women. VAR differed significantly between subjects with and without NAFLD (4.27 vs. 3.26 in men, 7.89 vs. 5.01 in women, respectively, p < .001). Logistic regression analysis determined VAR as a risk factor for NAFLD, and the multivariable-adjusted odds ratios in the highest VAR quartile was 9.57 (95%CI: 5.98-15.30) for men and 12.37 (95%CI: 6.37-24.05) for women. From the receiver operating characteristic analysis, the area under the curve was 0.767 and 0.834, with the suitable cut-off VAR value of 3.469 and 6.357 for men and women, respectively. To control the influence of obesity, all subjects were stratified according to their BMI. For each BMI group, individuals with VAR above the cut-off value had significant higher prevalence and risk of NAFLD, with odds ratios ranging from 1.76 to 4.75. CONCLUSIONS: Increased VAR is strongly associated with higher risk of NAFLD in both sexes independent of obesity and can serve as a screening reference for NAFLD.


Subject(s)
Non-alcoholic Fatty Liver Disease , Adult , Body Mass Index , Cross-Sectional Studies , Female , Humans , Intra-Abdominal Fat/diagnostic imaging , Male , Muscles , Non-alcoholic Fatty Liver Disease/diagnostic imaging , Non-alcoholic Fatty Liver Disease/epidemiology , Obesity/complications , Obesity/epidemiology , Risk Factors
19.
Pediatr Obes ; 16(3): e12718, 2021 03.
Article in English | MEDLINE | ID: mdl-32881371

ABSTRACT

BACKGROUND: Some studies have reported a relationship between obstructive sleep apnea (OSA) and non-alcoholic fatty liver disease (NAFLD) in pediatric population. However, this issue remains controversial. OBJECTIVES: The purpose of the present study was to investigate the association between OSA and NAFLD in pediatric population. METHODS: We systematically searched PubMed, Web of Science, Embase for eligible studies. The data involving markers of NAFLD including alanine aminotransferase (ALT), aspartate aminotransferase (AST), hepatic inflammation, hepatic fibrosis of both OSA group and control group were extracted. Pooled standardised mean difference (SMD) and weighted mean difference (WMD) were appropriately calculated through a fixed or random-effect model. RESULTS: Nine cross-sectional studies with 1133 children and adolescents were included. OSA was significantly associated with ALT, AST, and NAFLD fibrosis stage, but not NAFLD inflammation grade. Subgroup analysis indicated that both mild OSA and severe OSA were significantly associated with elevated ALT and AST. Furthermore, in the studies with all main confounding factors (age, gender, and BMI) matched, OSA group had higher ALT and AST levels than control group. CONCLUSIONS: This meta-analysis suggested that OSA was associated with NAFLD evidenced by elevated liver enzymes and progressive hepatic fibrosis in pediatric population. Screening and monitoring of NAFLD in pediatric patients with obesity-related OSA are necessary.


Subject(s)
Non-alcoholic Fatty Liver Disease/epidemiology , Sleep Apnea, Obstructive/epidemiology , Adolescent , Child , Cross-Sectional Studies , Humans
20.
J Clin Endocrinol Metab ; 106(2): e763-e771, 2021 01 23.
Article in English | MEDLINE | ID: mdl-33236101

ABSTRACT

CONTEXT: Osteoporosis and Parkinson's disease (PD) often co-occur, and even patients with early-stage PD may have reduced bone-mineral density levels. This may imply that osteoporosis is associated with a higher risk of PD. OBJECTIVES: This work aimed to determine whether patients with osteoporosis are at a higher risk of subsequently developing PD. DESIGN AND SETTING: A retrospective cohort study was conducted using Taiwan's National Health Insurance Research Database. PARTICIPANTS: A total of 23 495 individuals age 50 to 80 years who had osteoporosis between 2002 and 2006 were enrolled in the osteoporosis group. The comparison group comprised 23 495 propensity score-matched patients without osteoporosis. Their propensity scores were computed using a logistic regression model that included age, sex, comorbid conditions, and socioeconomic status. RESULTS: The hazard ratio (HR) of PD for the osteoporosis group was 1.31 times larger than that of the comparison group (95% CI, 1.13-1.50, P < .001). The PD-free survival rate of the osteoporosis group was also significantly lower than that of the comparison group (P < .001). The analyses stratified by sex showed that women with osteoporosis appeared to have a higher magnitude of PD HR (HR 1.50; 95% CI, 1.27-1.77, P < .001) than their male counterparts (HR 1.23; 95% CI, 0.93-1.64, P = .15). CONCLUSIONS: The present study's results suggest that osteoporosis is related to an increased risk of PD, especially among women.


Subject(s)
Osteoporosis/epidemiology , Parkinson Disease/epidemiology , Aged , Aged, 80 and over , Bone Density , Case-Control Studies , Female , Follow-Up Studies , Humans , Longitudinal Studies , Male , Middle Aged , Osteoporosis/complications , Parkinson Disease/etiology , Propensity Score , Retrospective Studies , Risk Factors , Taiwan/epidemiology
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