[Tetramethylpyrazine regulates angiogenesis of endothelial cells in cerebral ischemic stroke injury via SIRT1/VEGFA signaling pathway].

This study aims to investigate whether tetramethylpyrazine(TMP) can stimulate angiogenesis in cerebral microvascular endothelial cells and alleviate cerebral ischemic stroke(CIS) and to explore the underlying mechanisms. In the animal study, adult Sprague-Dawley rats(n=15) were assigned into sham surgery(sham), middle cerebral artery occlusion/reperfusion(MCAO/R), and MCAO/R+TMP(intraperitoneal injection of 20 mg·kg~(-1)) groups. The neurological function was evaluated by the Z-Longa method. The cerebral infarction volume was detected by TTC staining. Enzyme-linked immunosorbent assay(ELISA) was employed to detect the expression of vascular endothelial growth factor(VEGF), angiopoietin(Ang), and platelet-derived growth factor(PDGF). Immunofluorescence staining was employed to detect Ki67 and the expression of vascular endothelial growth factor A(VEGFA) and slient information regulator 1(SIRT1). Western blot was employed to determine the expression levels of VEGFA, SIRT1, angiopoietin-2(Ang-2), and platelet-derived growth factor B(PDGFB). In the cell study, mouse brain-derived endothelial cells(Bend.3) were cultured, and the optimal concentration of TMP was determined. Then, VEGF, Ang, and PDGF were detected by ELISA after the addition of cabozantinib. Western blot was employed to measure the expression of VEGFA, Ang-2, and PDGFB. Immunofluorescence staining was used to detect CD31, CD34, and Ki67, and the proliferation, migration, and tube formation ability of Bend.3 cells were observed in vitro. Western blot and immunofluorescence staining were performed to measure the expression of SIRT1 and VEGFA after addition of the SIRT1-specific inhibitor selisistat(EX-527). The results showed that compared with the sham group, the MCAO/R group had severe neurological function damage, increased infarction volume, up-regulated expression of VEGF, VEGFA, Ang, Ang-2, PDGF, and PDGFB, and down-regulated expression of Ki67 and SIRT1(P<0.01). Compared with the MCAO/R group, the MCAO/R+TMP group presented alleviated neurological function damage, reduced infarction volume, and activated expression of VEGF, VEGFA, Ang, Ang-2, PDGF, PDGFB, Ki67, and SIRT1(P<0.01). The cell experiments showed that compared with the normal group, Bend.3 cells were activated by oxygen glucose deprivation/reoxygenation(OGD/R) treatment(P<0.05, P<0.01). Compared with the OGD/R group, the OGD/R+TMP group upregulated the expression levels of VEGF, VEGFA, Ang, Ang-2, PDGF, PDGFB, SIRT1, Ki67, CD31, and CD34, enhanced the angiogenic ability of Bend.3 cells without being inhibited by BMS or EX-527(P<0.05, P<0.01, P<0.001). The results suggest that TMP can activate the SIRT1/VEGFA signaling pathway to stimulate angiogenesis and alleviate CIS injury.

Three New Labdane-Type Diterpenoids from the Fruits of Amomum villosum and Their Anti-Inflammatory Activities.

Three new labdane-type diterpenoids, calcaratarin E, villosumtriol, and 12-epi-villosumtriol (1-3) were isolated from the fruits of Amomum villosum, along with seven known diterpenoids (4-10). Through comprehensive analysis of chemical evidence and spectral data including UV, 1D and 2D NMR, HR-ESI-MS, IR, and X-ray crystallography, the structures of these novel compounds were successfully determined. Additionally, the inhibitory effects of compounds 2-10 on NO production in lipopolysaccharide (LPS)-induced RAW264.7 cells were evaluated. Notably, compound 6 exhibited the most significant inhibitory effect with an IC50 value of 1.74±0.69 µM.

Integrated analysis of tRNA-derived small RNAs in proliferative human aortic smooth muscle cells.

BACKGROUND: Abnormal proliferation of vascular smooth muscle cells (VSMCs) contributes to vascular remodeling diseases. Recently, it has been discovered that tRNA-derived small RNAs (tsRNAs), a new type of noncoding RNAs, are related to the proliferation and migration of VSMCs. tsRNAs regulate target gene expression through miRNA-like functions. This study aims to explore the potential of tsRNAs in human aortic smooth muscle cell (HASMC) proliferation. METHODS: High-throughput sequencing was performed to analyze the tsRNA expression profile of proliferative and quiescent HASMCs. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to validate the sequence results and subcellular distribution of AS-tDR-001370, AS-tDR-000067, AS-tDR-009512, and AS-tDR-000076. Based on the microRNA-like functions of tsRNAs, we predicted target promoters and mRNAs and constructed tsRNA-promoter and tsRNA-mRNA interaction networks. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed to reveal the function of target genes. EdU incorporation assay, Western blot, and dual-luciferase reporter gene assay were utilized to detect the effects of tsRNAs on HASMC proliferation. RESULTS: Compared with quiescent HASMCs, there were 1838 differentially expressed tsRNAs in proliferative HASMCs, including 887 with increased expression (fold change > 2, p < 0.05) and 951 with decreased expression (fold change < ½, p < 0.05). AS-tDR-001370, AS-tDR-000067, AS-tDR-009512, and AS-tDR-000076 were increased in proliferative HASMCs and were mainly located in the nucleus. Bioinformatics analysis suggested that the four tsRNAs involved a variety of GO terms and pathways related to VSMC proliferation. AS-tDR-000067 promoted HASMC proliferation by suppressing p53 transcription in a promoter-targeted manner. AS-tDR-000076 accelerated HASMC proliferation by attenuating mitofusin 2 (MFN2) levels in a 3'-untranslated region (UTR)-targeted manner. CONCLUSIONS: During HASMC proliferation, the expression levels of many tsRNAs are altered. AS-tDR-000067 and AS-tDR-000076 act as new factors promoting VSMC proliferation.

Afatinib Decreases P-Glycoprotein Expression to Promote Adriamycin Toxicity of A549T Cells.

We investigated the reversal effect of afatinib (AFT) on activity of adriamycin (ADR) in A549T cells and clarified the related molecular mechanisms. A549T cells overexpressing P-glycoprotein (P-gp) were resistant to anticancer drug ADR. AFT significantly increased the antitumor activity of ADR in A549T cells. AFT increased the intracellular concentration of ADR by inhibiting the function and expression of P-gp at mRNA and protein levels in A549T cells. Additionally, the reversal effect of AFT on P-gp mediated multidrug resistance (MDR) might be related to the inhibition of PI3K/Akt pathway. Cotreatment with AFT and ADR could enhance ADR-induced apoptosis and autophagy in A549T cells. Meanwhile, the co-treatment significantly induced cell apoptosis and autophagy accompanied by increased expression of cleaved caspase-3, PARP, LC3B-II, and beclin 1. Apoptosis inhibitors had no significant effect on cell activity, while autophagy inhibitors decreased cell viability, suggesting that autophagy may be a self protective mechanism of cell survival in the absence of chemotherapy drugs. Interestingly, when combined with AFT and ADR, inhibition of apoptosis and/or autophagy could enhance cell viability. These results indicated that in addition to inhibit P-gp, ADR-induced apoptosis, and autophagy promoted by AFT contributed to the antiproliferation effect of combined AFT and ADR on A549T cells. These findings provide evidence that AFT combined ADR may achieve a better therapeutic effect to lung cancer in clinic. J. Cell. Biochem. 119: 414-423, 2018. © 2017 Wiley Periodicals, Inc.

Alisol B 23-acetate protects against non-alcoholic steatohepatitis in mice via farnesoid X receptor activation.

Alisol B 23-acetate (AB23A) is a natural triterpenoid isolated from the traditional Chinese medicine rhizoma alismatis, which exhibits a number of pharmacological activities, including anti-hepatitis virus, anti-cancer and antibacterial effects. In this study we examined whether AB23A protected against non-alcoholic steatohepatitis (NASH) in mice, and the mechanisms underlying the protective effects. NASH was induced in mice fed a methionine and choline-deficient (MCD) diet for 4 weeks. The mice were simultaneously treated with AB23A (15, 30, and 60 mg·kg-1·d-1, ig) for 4 weeks. On the last day, blood samples and livers were collected. Serum liver functional enzymes, inflammatoru markers were assessed. The livers were histologically examined using H&E, Oil Red O, Masson's trichrome and Sirius Red staining. Mouse primary hepatocytes were used for in vitro experiments. The mechanisms underlying AB23A protection were analyzed using siRNA, qRT-PCR, and Western blot assays. AB23A treatment significantly and dose-dependently decreased the elevated levels of serum ALT and AST in MCD diet-fed mice. Furthermore, AB23A treatment significantly reduced hepatic triglyceride accumulation, inflammatory cell infiltration and hepatic fibrosis in the mice. AB23A-induced decreases in serum and hepatic lipids were related to decreased hepatic lipogenesis through decreasing hepatic levels of SREBP-1c, FAS, ACC1 and SCD1 and increased lipid metabolism via inducing PPARα, CPT1α, ACADS and LPL. The reduction in inflammatory cell infiltration corresponded to deceased serum levels of mKC and MCP-1 and decreased hepatic gene expression of MCP-1 and VCAM-1. The reduction in hepatic fibrosis was correlated with decreased hepatic gene expression of fibrosis markers. The protective effects of AB23A were FXR-dependent, because treatment with the FXR agonist CDCA mimicked AB23A-induced hepato-protection in the mice, whereas co-administration of FXR antagonist guggulsterone abrogated AB23A-induced hepato-protection. In mouse primary hepatocytes, FXR gene silencing abrogated AB23A-induced changes in gene expression of Apo C-II, CPT1α, ACADS and LPL. AB23A produces protective effects against NASH in mice via FXR activation.

[Research advances in organic anion transporter].

The organic anion transporter (OAT) subfamily is an important part of the SLC22 (solute carrier 22) transporter family. OATs are expressed in many tissues, including liver, kidney, brain, placenta and so on. A great deal of attention has been paid to OAT because of its role in handling of common drugs (antibiotics, antivirals, diuretics, nonsteroidal anti-inflammatory drugs), toxins and nutrients. Data from recent metabolomics, microarray and system biology studies, phenotypes of Oat1 and Oat3 knockouts, indicate a central role of this pathway in the metabolism as well as putative uremic toxins of kidney disease. The expressions of certain OATs in conjunction with phase I and phase II drug metabolizing enzymes are regulated by nuclear receptors and other transcription factors. According to the "remote sensing and signaling hypothesis", some OATs have a strong relationship with certain particular signaling molecules. OATs may play a role in remote inter-organ communication via regulating levels of signaling molecules and key metabolites in tissues and body fluids. OATs play a significant role in the transportation of internal and external material under normal and pathological conditions.

[Progress in regulation of drug transporters and metabolic enzymes by resveratrol].

Drug transporters and metabolic enzymes are two major factors in the regulation of disposition of drug in the body. Interestingly, resveratrol, as a new star of anticancer drug, has a close relationship with transporters and metabolic enzymes. It is known that resveratrol can activate or inhibit the function of several transporters directly. Furthermore, the expression of several transporters was changed. Meanwhile, resveratrol is able to inhibit the function of metabolic enzymes (cytochrome P450, CYP450) and regulate the expression of metabolic enzymes. For this reason, when resveratrol is administrated in combination with other drugs, drug-drug interaction (DDI) should be considered. In this review, we summarize the distribution of transporters and metabolic enzymes in the body, the effect of resveratrol on transporters and metabolic enzymes as well as the drug-resveratrol interaction mediated by transporters and metabolic enzymes.

Alpha-Lipoic Acid Promotes Osteoblastic Formation in H2O2 -Treated MC3T3-E1 Cells and Prevents Bone Loss in Ovariectomized Rats.

Alpha-lipoic acid (ALA), a naturally occurring compound and dietary supplement, has been established as a potent antioxidant that is a strong scavenger of free radicals. Recently, accumulating evidences has indicated the relationship between oxidative stress and osteoporosis (OP). Some studies have investigated the possible beneficial effects of ALA on OP both in vivo and in vitro; however, the precise mechanism(s) underlying the bone-protective action of ALA remains unclear. Considering this, we focused on the anti-oxidative capacity of ALA to exert bone-protective effects in vitro and in vivo. In the present study, the effects of ALA on osteoblastic formation in H(2)O(2) -treated MC3T3-E1 pre-osteoblasts and ovariectomy (OVX)-induced bone loss in rats were investigated. The results showed that ALA promoted osteoblast differentiation, mineralization and maturation and inhibited osteoblast apoptosis, thus increasing the OPG/receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL) ratio and leading to enhanced bone formation in vitro and inhibited bone loss in vivo. Further study revealed that ALA exerted its bone-protective effects by inhibiting reactive oxygen species (ROS) generation by down-regulating Nox4 gene expression and protein synthesis and attenuating the transcriptional activation of NF-κB. In addition, ALA might exert its bone-protective effects by activating the Wnt/Lrp5/ß-catenin signaling pathway. Taken together, the present study indicated that ALA promoted osteoblastic formation in H(2)O(2) -treated MC3T3-E1 cells and prevented OVX-induced bone loss in rats by regulating Nox4/ROS/NF-κB and Wnt/Lrp5/ß-catenin signaling pathways, which provided possible mechanisms of bone-protective effects in regulating osteoblastic formation and preventing bone loss. Taken together, the results suggest that ALA may be a candidate for clinical OP treatment.

Alisol B 23-acetate protects against ANIT-induced hepatotoxity and cholestasis, due to FXR-mediated regulation of transporters and enzymes involved in bile acid homeostasis.

Intrahepatic cholestasis is a clinical syndrome with systemic and intrahepatic accumulation of excessive toxic bile acids that ultimately cause hepatobiliary injury. Appropriate regulation of bile acids in hepatocytes is critically important for protection against liver injury. In the present study, we characterized the protective effect of alisol B 23-acetate (AB23A), a natural triterpenoid, on alpha-naphthylisothiocyanate (ANIT)-induced liver injury and intrahepatic cholestasis in mice and further elucidated the mechanisms in vivo and in vitro. AB23A treatment dose-dependently protected against liver injury induced by ANIT through reducing hepatic uptake and increasing efflux of bile acid via down-regulation of hepatic uptake transporters (Ntcp) and up-regulation of efflux transporter (Bsep, Mrp2 and Mdr2) expression. Furthermore, AB23A reduced bile acid synthesis through repressing Cyp7a1 and Cyp8b1, increased bile acid conjugation through inducing Bal, Baat and bile acid metabolism through an induction in gene expression of Sult2a1. We further demonstrate the involvement of farnesoid X receptor (FXR) in the hepatoprotective effect of AB23A. The changes in transporters and enzymes, as well as ameliorative liver histology in AB23A-treated mice were abrogated by FXR antagonist guggulsterone in vivo. In vitro evidences also directly demonstrated the effect of AB23A on FXR activation in a dose-dependent manner using luciferase reporter assay in HepG2 cells. In conclusion, AB23A produces protective effect against ANIT-induced hepatotoxity and cholestasis, due to FXR-mediated regulation of transporters and enzymes.

Inhibitory Effects of Highly Oxygenated Lanostane Derivatives from the Fungus Ganoderma lucidum on P-Glycoprotein and α-Glucosidase.

Twelve new highly oxygenated lanostane triterpenoids and nine known ganoderic acids were isolated from the fruiting body of Ganoderma lucidum. The new compounds were lanostane nortriterpenoids with 27 carbons (1-5 and 8), lanostane nor-triterpenoids with 25 carbons (6 and 7), and lanostane triterpenoids (9-12) based on multiple spectroscopic data analysis, including HRESIMS, 1D-NMR, 2D-NMR, and CD. Compounds 1-5 were identified as rare nor-lanostanoids that contain a 17ß-pentatomic lactone ring. Compound 13, possessing a lactone ring, had been isolated previously. The P-glycoprotein (P-gp) inhibitory effects of compounds 1-21 were evaluated at a concentration of 20 µM using an adriamycin (ADM)-resistant human breast adenocarcinoma cell line (MCF-7/ADR). Compounds 1, 5, 18, and 20 and verapamil increased the accumulation of ADM in MCF-7/ADR cells approximately 3-fold when compared with the negative control. These data support the significant P-glycoprotein inhibitory activities of compounds 1, 5, 18, and 20. In silico docking analysis suggested these compounds had similar P-gp recognition mechanisms compared with those of verapamil (a classical inhibitor). Furthermore, in an in vitro bioassay, compounds 2, 4, 5, 6, and 18 showed moderate inhibitory effects against α-glucosidase compared with those of the positive control acarbose.

A novel oleanolic acid-loaded PLGA-TPGS nanoparticle for liver cancer treatment.

OBJECTIVES: Hepatocellular carcinoma is the third most common cause of cancer death. Oleanolic acid (OA) is a natural triterpenoid, has many important biological actions, including antitumor effect, but its poor solubility often leads to poor pharmacodynamics. The aim of our work is to make OA-loaded poly (lactide-co-glycolide)-d-α-tocopheryl polyethylene glycol 1000 succinate (PLGA-TPGS) nanoparticles (OPTN) to improve its efficacy to liver cancer and characterize it. METHODS: OPTN were prepared by ultrasonic emulsification-solvent evaporation technique using PLGA with or without the addition of TPGS (OPN). The coumarin-6-loaded nanoparticles were used as a fluorescence marker. The nanoparticles were characterized for surface morphology, surface charge, particle size, drug loading, encapsulation efficiency, in vitro drug-release, cellular uptake, cytotoxicity by human liver cancer cell line HepG2 cells, and therapeutic effect in vivo. KEY FINDINGS: The prepared nanoparticles were found to be spherical in shape. The in vitro drug-release profile of both nanoparticle formulations showed a biphasic release pattern. There was an increased level of uptake and cytotoxicity of OPTN in the HepG2 cells compared with that of OPN. The treatment of OPTN group was better than OPN and FS groups in vivo. CONCLUSION: The results showed advantages of OPTN in terms of sustainable release and efficacy in liver cancer chemotherapy compared with OPN. OPTN could be acted as a novel and new dosage form to be used in cancer treatment study.

[Advances in the study of enzymes and transporters-mediated pharmacokinetic mechanism for herb-drug interaction].

With the wide application of Chinese herbal medicine, herb-drug interaction (HDI) has become increasingly prominent. Metabolic enzymes and transporters are the main targets of HDI, because the changes in expression and function of enzymes and transporters can influence the disposition of drugs. Metabolic enzymes are responsible for the metabolic clearance of drugs, including cytochrome P450 (CYP), UDP-glucuronyl transferase (UGT) and sulfotransferases (SULT); transporters widely expressed in the intestine, kidney, liver and brain are involved in the oral absorption, distribution and excretion of drugs. Pueraria, ginkgo, ginseng, St. John's wort and other Chinese herbal medicine often induce a HDI because those herbal medicines combined with chemical medicine are widely used in clinic. The components of herb medicines mentioned above are prone to interact with enzymes and transporters, which often induce a HDI. This paper reviews the advances in the study of enzymes and transporters-mediated pharmacokinetic mechanism of HDI.

[Advances of the anti-tumor research of metformin].

Metformin is the most commonly prescibed drug for type 2 diabetes mellitus as it is inexpensive, safe, and efficient in ameliorating hyperglycemia and hyperinsulinemia. Numerous epidemiological studies indicate that diabetic population is not only at increased risk of cardiovascular complications, but also at substantially higher risk of many forms of malignancies. Meanwhile, epidemiological and clinical observation studies have shown that metformin use reduces risk of cancer in patients with type 2 diabetes mellitus and improves prognosis and survival rate of the cancer patients. Furthermore, metformin has been used for cancer therapy in clinical trials. Thus, metformin is emerging as a new cancer therapy or adjuvant anticancer drugs. This review summarizes recent progress in studies of metformin use and its molecular mechanism.

[Alteration of related transporters and its application significance in common intestinal disease, liver disease, renal disease and diabetes].

Drug transporters are functional membrane proteins located in various tissues, which play vital roles in absorption, distribution and excretion of drugs, especially those located in intestine, liver and kidney. The expression and function of transporters will alter in diseases state, which affects the therapeutic effects of drugs by altering their pharmacokinetics. In this review, we focus on the alterations in related transporters and the effect on the drug therapy in common intestinal diseases, liver diseases, kidney diseases and diabetes mellitus.

[The drug-drug interaction mediated by efflux transporters and CYP450 enzymes].

Multidrug regimens and corresponding drug interactions cause many adverse reactions and treatment failures. Drug efflux transporters: P-glycoprotein (P-gp), multidrug resistance associated protein (MRP) and breast cancer resistance protein (BCRP) in conjunction with metabolizing enzymes (cytochrome P450, CYP450) are major factors in such interaction. In recent years, a large number of studies have shown that P-gp plays a role in the oxidative metabolism of its substrates that are also substrates of CYP3A4. Combined actions of P-gp and CYP3A could account in some part for the low oral bioavailability determined for many of these dual substrates. P-gp along with efflux transporters (MRP and BCRP) having overlapping substrate specificity plays critical role in drug disposition. The relationship between MRP or BCRP and CYP3A is similar to that between P-gp and CYP3A. In this paper, we summarize the classification of efflux transporters, the main metabolizing enzymes CYP3A, clinical significance interactions mediated by efflux transporters and CYP450 enzymes and in vitro studies.

Effect of exogenous γ-aminobutyric acid on physiological property, antioxidant activity, and cadmium uptake of quinoa seedlings under cadmium stress.

Increasing cadmium (Cd) pollution has negative effects on quinoa growth and production. Gamma-aminobutyric acid (GABA) confers plants with stress resistance to heavy metals; however, the mechanism remains unclear. We explored the effects of exogenous GABA on the physiological characteristics, antioxidant capacity, and Cd accumulation of quinoa seedlings under Cd stress using hydroponic experiments. Partial least-squares regression was used to identify key physical and chemical indices of seedlings affecting Cd accumulation. Compared with those of the CK group, exposure to 10 and 25 µmol·L-1 Cd significantly reduced the photosynthetic pigment contents, photosynthesis, and biomass accumulation of quinoa seedlings; resulted in shorter and thicker roots; decreased the length of the lateral roots; decreased the activities of superoxide dismutase (SOD) and peroxide (POD); and increased H2O2 and malondialdehyde (MDA) contents. Exogenous GABA reduced the Cd content in the stem/leaves and roots of quinoa seedlings under Cd stress by 13.22-21.63% and 7.92-28.32%, decreased Cd accumulation by 5.37-6.71% and 1.91-4.09%, decreased the H2O2 content by 38.21-47.46% and 45.81-55.73%, and decreased the MDA content by 37.65-48.12% and 29.87-32.51%, respectively. GABA addition increased the SOD and POD activities in the roots by 2.78-5.61% and 13.81-18.33%, respectively, under Cd stress. Thus, exogenous GABA can reduce the content and accumulation of Cd in quinoa seedlings by improving the photosynthetic characteristics and antioxidant enzyme activity and reducing the degree of lipid peroxidation in the cell membrane to alleviate the toxic effect of Cd stress on seedling growth.

Efficacy and safety of perioperative therapy for locally resectable gastric cancer: A network meta-analysis of randomized clinical trials.

BACKGROUND: Gastric cancer (GC) is the fifth most commonly diagnosed malignancy worldwide, with over 1 million new cases per year, and the third leading cause of cancer-related death. AIM: To determine the optimal perioperative treatment regimen for patients with locally resectable GC. METHODS: A comprehensive literature search was conducted, focusing on phase II/III randomized controlled trials (RCTs) assessing perioperative chemotherapy and chemoradiotherapy in treating locally resectable GC. The R0 resection rate, overall survival (OS), disease-free survival (DFS), and incidence of grade 3 or higher nonsurgical severe adverse events (SAEs) associated with various perioperative regimens were analyzed. A Bayesian network meta-analysis was performed to compare treatment regimens and rank their efficacy. RESULTS: Thirty RCTs involving 8346 patients were included in this study. Neoadjuvant XELOX plus neoadjuvant radiotherapy and neoadjuvant CF were found to significantly improve the R0 resection rate compared with surgery alone, and the former had the highest probability of being the most effective option in this context. Neoadjuvant plus adjuvant FLOT was associated with the highest probability of being the best regimen for improving OS. Owing to limited data, no definitive ranking could be determined for DFS. Considering nonsurgical SAEs, FLO has emerged as the safest treatment regimen. CONCLUSION: This study provides valuable insights for clinicians when selecting perioperative treatment regimens for patients with locally resectable GC. Further studies are required to validate these findings.

[Source and Cause Analysis of High Concentration of Inorganic Aerosol During Two Typical Pollution Processes in Winter over Tianjin].

Inorganic aerosol is the main component of haze days in winter over Tianjin. In this study, two typical high concentrations of secondary inorganic aerosol (SIA) processes, defined as CASE1 and CASE2, were selected during polluted days in January 2020 over Tianjin, and the effects of meteorological factors, regional transport, and chemical processes were comprehensively investigated combined with observations and numerical models (WRF-NAQPMS). The average SIA concentrations in CASE1 and CASE2 were 76.8 µg·m-3 and 66.0 µg·m-3, respectively, and the nitrate concentration was higher than that of sulfate and ammonium, which were typical nitrate-dominated pollution processes. Meteorological conditions played a role in inorganic aerosol formation. The temperature of approximately -6-0℃ and 2-4℃ and the relative humidity of 50%-60% and 80%-100% would be suitable conditions for the high SIA concentration (>80 µg·m-3) in CASE1, whereas the temperature of approximately 2-4℃ and the relative humidity of 60%-70% would be suitable in CASE2. The average contribution rates of external sources to SIA in the CASE1 and CASE2 processes were 62.3% and 22.1%, which were regional transport-dominant processes and local emission-dominant processes, respectively. The contribution of the local emission of CASE1 to nitrate and sulfate was 16.2 µg·m-3 and 8.2 µg·m-3, respectively, higher than that of external sources (31.7 µg·m-3 and 8.8 µg·m-3). the local contribution of CASE2 to nitrate and sulfate was 29.3 µg·m-3 and 25.1 µg·m-3, respectively, whereas the contribution from external sources was 8.1 µg·m-3 and 9.4 µg·m-3, respectively. The quantitative result indicated that local formation and regional transport resulted in higher nitrate concentration than sulfate in CASE1, in contrast to only local sources in CASE2. The gas phase reaction was the main source of inorganic aerosol formation, contributing 48.9% and 57.8% in CASE1 and CASE2, respectively, whereas the heterogeneous reactions were also important processes, with contribution rates of 48.1% and 42.2% to SIA. The effect of aqueous phase reaction was negligible.

Intermittent fasting and health outcomes: an umbrella review of systematic reviews and meta-analyses of randomised controlled trials.

Background: Benefits of Intermittent fasting (IF) on health-related outcomes have been found in a range of randomised controlled trials (RCTs). Our umbrella review aimed to systematically analyze and synthesize the available causal evidence on IF and its impact on specific health-related outcomes while evaluating its evidence quality. Methods: We comprehensively searched the PubMed, Embase, Web of Science, and Cochrane databases (from inception up to 8 January 2024) to identify related systematic reviews and meta-analyses of RCTs investigating the association between IF and human health outcomes. We recalculated the effect sizes for each meta-analysis as mean difference (MD) or standardized mean difference (SMD) with corresponding 95% confidence intervals (CIs). Subgroup analyses were performed for populations based on three specific status: diabetes, overweight or obesity, and metabolic syndrome. The quality of systematic reviews was evaluated using A Measurement Tool to Assess Systematic Reviews (AMSTAR), and the certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) system. This study is registered with PROSPERO (CRD42023382004). Findings: A total of 351 associations from 23 meta-analyses with 34 health outcomes were included in the study. A wide range of outcomes were investigated, including anthropometric measures (n = 155), lipid profiles (n = 83), glycemic profiles (n = 57), circulatory system index (n = 41), appetite (n = 9), and others (n = 6). Twenty-one (91%) meta-analyses with 346 associations were rated as high confidence according to the AMSTAR criteria. The summary effects estimates were significant at p < 0.05 in 103 associations, of which 10 (10%) were supported by high certainty of evidence according to GRADE. Specifically, compared with non-intervention diet in adults with overweight or obesity, IF reduced waist circumference (WC) (MD = -1.02 cm; 95% CI: -1.99 to -0.06; p = 0.038), fat mass (MD = -0.72 kg; 95% CI: -1.32 to -0.12; p = 0.019), fasting insulin (SMD = -0.21; 95% CI: -0.40 to -0.02; p = 0.030), low-density lipoprotein cholesterol (LDL-C) (SMD = -0.20; 95% CI: -0.38 to -0.02; p = 0.027), total cholesterol (TC) (SMD = -0.29; 95% CI: -0.48 to -0.10; p = 0.003), and triacylglycerols (TG) (SMD = -0.23; 95% CI: -0.39 to -0.06; p = 0.007), but increased fat free mass (FFM) (MD = 0.98 kg; 95% CI: 0.18-1.78; p = 0.016). Of note, compared with the non-intervention diet, modified alternate-day fasting (MADF) reduced fat mass (MD = -0.70 kg; 95% CI: -1.38 to -0.02; p = 0.044). In people with overweight or obesity, and type 2 diabetes, IF increases high-density lipoprotein cholesterol (HDL-C) levels compared to continuous energy restriction (CER) (MD = 0.03 mmol/L; 95% CI: 0.01-0.05; p = 0.010). However, IF was less effective at reducing systolic blood pressure (SBP) than a CER diet in adults with overweight or obesity (SMD = 0.21; 95% CI: 0.05-0.36; p = 0.008). Interpretation: Our findings suggest that IF may have beneficial effects on a range of health outcomes for adults with overweight or obesity, compared to CER or non-intervention diet. Specifically, IF may decreased WC, fat mass, LDL-C, TG, TC, fasting insulin, and SBP, while increasing HDL-C and FFM. Notably, it is worth noting that the SBP lowering effect of IF appears to be weaker than that of CER. Funding: This work was supported by the National Key Research and Development Program of China (Q-JW), the Natural Science Foundation of China (Q-JW and T-TG), Outstanding Scientific Fund of Shengjing Hospital of China Medical University (Q-JW), and 345 Talent Project of Shengjing Hospital of China Medical University (T-TG).

Per- and polyfluoroalkyl substances and human health outcomes: An umbrella review of systematic reviews with meta-analyses of observational studies.

BACKGROUND: Although evidence on the association between per- and polyfluoroalkyl substances (PFASs) and human health outcomes has grown exponentially, specific health outcomes and their potential associations with PFASs have not been conclusively evaluated. METHODS: We conducted a comprehensive search through the databases of PubMed, Embase, and Web of Science from inception to February 29, 2024, to identify systematic reviews with meta-analyses of observational studies examining the associations between the PFASs and multiple health outcomes. The quality of included studies was evaluated using the A Measurement Tool to Assess Systematic Reviews (AMSTAR) tool, and credibility of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) criteria. The protocol of this umbrella review (UR) had been registered in PROSPERO (CRD 42023480817). RESULTS: The UR identified 157 meta-analyses from 29 articles. Using the AMSTAR measurement tool, all articles were categorized as of moderate-to-high quality. Based on the GRADE assessment, significant associations between specific types of PFASs and low birth weight, tetanus vaccine response, and triglyceride levels showed high certainty of evidence. Moreover, moderate certainty of evidence with statistical significance was observed between PFASs and health outcomes including lower BMI z-score in infancy, poor sperm progressive motility, and decreased risk of preterm birth as well as preeclampsia. Fifty-two (33%) associations (e.g., PFASs and gestational hypertension, cardiovascular disease, etc) presented low certainty evidence. Additionally, eighty-five (55%) associations (e.g., PFASs with infertility, lipid metabolism, etc) presented very low certainty evidence. CONCLUSION: High certainty of evidence supported that certain PFASs were associated with the incidence of low birth weight, low efficiency of the tetanus vaccine, and low triglyceride levels.