Insights into the response mechanisms of Tetradesmus obliquus to aged polylactic acid and tetracycline exposure via transcriptome analysis and physiological evaluations.

Microplastics (MPs) and antibiotics, identified as emerging pollutants, are extensively prevalent in aquatic environments and display prolonged durability. Unlike conventional plastics, biodegradable plastics are more susceptible to decomposition in the environment, resulting in the generation of microplastics and posing potential risks to the aquatic ecosystems. In this study, we assessed growth inhibition, chlorophyll a content, malondialdehyde content (MDA), and antioxidant enzyme activities. These measurements were integrated with transcriptome analysis to explore the response mechanisms of virgin and aged polylactic acid (vPLA and aPLA) and tetracycline (TC) following 14-day exposure to Tetradesmus obliquus, either individually or in combination. The findings indicated that exposure to vPLA did not significantly impact the growth of T. obliquus. Conversely, aPLA demonstrated growth-promoting effects on T. obliquus, particularly in the latter incubation stages. Moreover, a 14-day exposure significantly increased the chlorophyll a content and the activities of superoxide dismutase (SOD), catalase glutathione (CAT) and glutathione S-transferase (GST) within the algal cells. Apart from 1 mg L-1, the TC concentrations of 2.5, 5.0, and 10 mg L-1 exhibited significant toxic effects on T. obliquus, including growth inhibition, decreased chlorophyll a content, elevated activities of SOD, CAT, and GST, and increased MDA levels. Exposure to a combination of 300 mg L-1 aPLA and 5.0 mg L-1 TC, compared to solely 5 mg L-1 TC, demonstrated a notable reduction in TC toxicity to T. obliquus in the presence of aPLA. This was indicated by elevated algal cell density and chlorophyll a content, as well as a decrease in MDA content. Transcriptome analysis indicated an enrichment of differentially expressed genes (DEGs) in pathways linked to porphyrin metabolism, photosynthesis, carbon fixation, and metabolism within the aPLA + TC combined exposure. The study aid in expanding our knowledge of the potential ecological risks posed by biodegradable plastics and accompanying pollutants in aquatic environments.

Accelerated aging behavior of degradable and non-degradable microplastics via advanced oxidation and their adsorption characteristics towards tetracycline.

The increasing global utilization of biodegradable plastics due to stringent regulations on traditional plastics has caused a significant rise in microplastic (MPs) pollution in aquatic ecosystems from biodegradable products. However, the environmental behavior of biodegradable MPs remains inadequately elucidated. This study explored the aging processes of polylactic acid (PLA) and polystyrene (PS) under a heat-activated potassium persulfate (K2S2O8) system, as well as their adsorption characteristics towards tetracycline (TCs). In comparison to PS, the surface structure of PLA experienced more pronounced changes over aging, exhibiting evident pits, cracks, and fragmentation. The carbonyl index (CI) and oxygen/carbon ratio (O/C) of PS displayed exponential growth over time, whereas the values for PLA showed linear and exponential increases, respectively. The adsorption capacity of TCs by PS and PLA aged for 6 days increased from 0.312 mg‧g-1 and 0.457 mg‧g-1for original PS and PLA, respectively, to 0.372 mg‧g-1 and 0.649 mg‧g-1. Meanwhile, the adsorption rate (k2 values) for TCs decreased by 42.03 % for PS and 79.64 % for PLA compared to their initial values. The findings indicated that biodegradable PLA-MPs may exhibit higher tetracycline carrying capacities than PS, potentially increasing environmental and organismal risks, particularly in view of aging effects.

Correction: Feng et al. Electrolyte Analysis in Blood Serum by Laser-Induced Breakdown Spectroscopy Using a Portable Laser. Molecules 2022, 27, 6438.

In the original publication [...].

The Integration of Systematic Pharmacology and Experimental Validation to Explain the Mechanism of Action of Wuling Capsule in the Treatment of NAFLD.

BACKGROUND: Wuling capsule is a traditional Chinese medicine composed of four herbals. It has been widely used to treat chronic active hepatitis and has shown significant efficacy in hyperlipidemia. However, the treatment of NAFLD disease has not been studied in depth. METHODS: Firstly, the potential bioactive compounds in Wuling capsules were identified by TCMSP (https://old.tcmsp-e.com/tcmsp.php). Secondly， the pathway and GO function were analyzed by using the DAVID database (https://david.ncifcrf.gov/). Then, the molecular docking techniques were used to confirm the accuracy of binding between key targets and components. Furthermore, the experimental pharmacology validation was conducted using RT-qPCR and WB of the NAFLD model. RESULTS: A total of 138 active compounds and 40 common potential targets associated with NAFLD were identified through network pharmacology. The pathway and functional enrichment analysis showed that the Wuling capsule was associated with the PI3K-AKT and HIF-1α signaling pathways. In vivo experiments showed that the Wuling capsule could reduce IL-6, TNF-α, and HIF-1α proteins and up-regulate STAT3 and VEGFA levels (P < 0.05), thus alleviating liver inflammation. CONCLUSIONS: With the support of network pharmacology and animal experiments, the study preliminarily investigated the effect of the Wuling capsule on liver inflammation by regulating the HIF-1α signaling pathway, thereby protecting liver function and treating NAFLD.

Glioma-targeted oxaliplatin/ferritin clathrate reversing the immunosuppressive microenvironment through hijacking Fe2+ and boosting Fenton reaction.

Glioma is easy to develop resistance to temozolomide (TMZ). TMZ-resistant glioma secretes interleukin-10 (IL-10) and transforming growth factor-ß (TGF-ß), recruiting regulatory T cell (Treg) and inhibiting the activity of T cells and natural killer cell (NK cell), subsequently forming an immunosuppressive microenvironment. Oxaliplatin (OXA) greatly inhibits the proliferation of TMZ-resistant glioma cells, but the ability of OXA to cross blood-brain barrier (BBB) is weak. Thus, the therapeutic effect of OXA on glioma is not satisfactory. Transferrin receptor 1 (TfR1) is highly expressed in brain capillary endothelial cells and TMZ-resistant glioma cells. In this study, OXA was loaded into ferritin (Fn) to prepare glioma-targeted oxaliplatin/ferritin clathrate OXA@Fn. OXA@Fn efficiently crossed BBB and was actively taken up by TMZ-resistant glioma cells via TfR1. Then, OXA increased the intracellular H2O2 level and induced the apoptosis of TMZ-resistant glioma cells. Meanwhile, Fn increased Fe2+ level in TMZ-resistant glioma cells. In addition, the expression of ferroportin 1 was significantly reduced, resulting in Fe2+ to be locked up inside the TMZ-resistant glioma cells. This subsequently enhanced the Fenton reaction and boosted the ferroptosis of TMZ-resistant glioma cells. Consequently, T cell mediated anti-tumor immune response was strongly induced, and the immunosuppressive microenvironment was significantly reversed in TMZ-resistant glioma tissue. Ultimately, the growth and invasion of TMZ-resistant glioma was inhibited by OXA@Fn. OXA@Fn shows great potential in the treatment of TMZ-resistant glioma and prospect in clinical transformation.

A novel 4-(1,3,4-thiadiazole-2-ylthio)pyrimidine derivative inhibits cell proliferation by suppressing the MEK/ERK signaling pathway in colorectal cancer.

Colorectal cancer (CRC) is one of the most common types of malignant cancers worldwide. Although molecularly targeted therapies have significantly improved treatment outcomes, most of these target inhibitors are resistant. Novel inhibitors as potential anticancer drug candidates are still needed to be discovered. Therefore, in the present study, we synthesized a novel 4-(1,3,4-thiadiazole-2-ylthio)pyrimidine derivative (compound 4) using fragment- and structure-based techniques and then investigated the anticancer effect and underlying mechanism of anti-CRC. The results revealed that compound 4 significantly inhibited HCT116 cell proliferation with IC 50 values of 8.04 ± 0.94 µmol L-1 after 48 h and 5.52 ± 0.42 µmol L-1 after 72 h, respectively. Compound 4 also inhibited colony formation, migration, and invasion of HCT116 cells in a dose-dependent manner, as well as inducing cell apoptosis and arresting the cell cycle in the G2/M phase. In addition, compound 4 was able to inhibit the activation of the MEK/ERK signaling in HCT116 cells. And compound 4 yielded the same effects as the MEK inhibitor U0126 on cell apoptosis and MEK/ERK-related proteins. These findings suggested that compound 4 inhi bited cell proliferation and growth, and induced cell apoptosis, indicating its use as a novel and potent anticancer agent against CRC via the MEK/ERK signaling pathway.

Calcium phosphate hybrid micelles inhibit orthotopic bone metastasis from triple negative breast cancer by simultaneously killing cancer cells and reprogramming the microenvironment of bone resorption and immunosuppression.

Triple negative breast cancer (TNBC) is prone to develop drug resistance and metastasis. Bone is the most common distant metastasis site of breast cancer cell. Patients with bone metastasis from TNBC suffer from unbearable pain due to the growth of bone metastasis and bone destruction. Simultaneously blocking the growth of bone metastasis and reprogramming the microenvironment of bone resorption and immunosuppression is a promising strategy to treat bone metastasis from TNBC. Herein, we prepared a pH and redox responsive drug delivery system, named DZ@CPH, by encapsulating docetaxel (DTX) with hyaluronic acid-polylactic acid micelle then reinforcing with calcium phosphate and zoledronate for targeting to bone metastasis from TNBC. DZ@CPH reduced the activation of osteoclast and inhibited bone resorption by decreasing the expression of nuclear factor κB receptor ligand and increasing the expression of osteoprotegerin in drug-resistant bone metastasis tissue. At the same time, DZ@CPH inhibited the invasion of bone metastatic TNBC cells by regulating the apoptosis-related and invasion-related protein expression. It also increased the sensitivity of orthotopic drug-resistant bone metastasis to DTX by inhibiting the expression of P-glycoprotein, Bcl-2 and transforming growth factor-ß in tissue of drug-resistant bone metastasis. Moreover, the ratio between M1 type macrophage to M2 type macrophage in bone metastasis tissue was increased by DZ@CPH. In a word, DZ@CPH blocked the growth of bone metastasis from drug-resistant TNBC through inducing the apoptosis of drug-resistant TNBC cells and reprogramming the microenvironment of bone resorption and immunosuppression. DZ@CPH has a great potential in clinical application for the treatment of bone metastasis from drug-resistant TNBC. STATEMENT OF SIGNIFICANCE: Triple negative breast cancer (TNBC) is prone to develop bone metastasis. Now bone metastasis is still an intractable disease. In this study, docetaxel and zoledronate co-loaded calcium phosphate hybrid micelles (DZ@CPH) were prepared. DZ@CPH reduced the activation of osteoclasts and inhibited bone resorption. At the same time, DZ@CPH inhibited the invasion of bone metastatic TNBC cells by regulating the expression of apoptosis and invasion related protein in bone metastasis tissue. Moreover, the ratio between M1 type macrophages to M2 type macrophages in bone metastases tissue was increased by DZ@CPH. In a word, DZ@CPH blocked vicious cycle between the growth of bone metastasis and bone resorption, which greatly improved the therapeutic effect on bone metastasis from drug-resistant TNBC.

Mechanism of Huangqi-Honghua combination regulating the gut microbiota to affect bile acid metabolism towards preventing cerebral ischaemia-reperfusion injury in rats.

CONTEXT: Effective treatment of ischaemic stroke is required to combat its high prevalence and incidence. Although the combination of Astragalus membranaeus (Fisch.) Bge. (Fabaceae) and Carthamus tinctorius L. (Asteraceae) is used in traditional Chinese medicine for the treatment of stroke, its underlying mechanism remains unclear. OBJECTIVE: The objective of this study is to elucidate the mechanism underlying Huangqi-Honghua (HQ-HH) for the treatment of ischaemic stroke by gut microbiota analysis and metabonomics. MATERIALS AND METHODS: Sprague-Dawley rats were randomly assigned to the sham, model, HQ-HH, and Naoxintong (NXT) groups. The middle cerebral artery occlusion-reperfusion model was established after 7 days of intragastric administration in the HQ-HH (4.5 g/kg, qd) and NXT (1.0 g/kg, qd) groups. The neurological examination, infarct volume, gut microbiota, bile acids, and inflammation markers were assessed after 72 h of reperfusion. RESULTS: Compared with the model group, HQ-HH significantly reduced the neurological deficit scores of the model rats (2.0 ± 0.2 vs. 3.16 ± 0.56), and reduced the cerebral infarct volume (27.83 ± 3.95 vs. 45.17 ± 2.75), and reduced the rate of necrotic neurons (26.35 ± 4.37 vs. 53.50 ± 9.61). HQ-HH regulating gut microbiota, activating the bile acid receptor FXR, maintaining the homeostasis of bile acid, reducing Th17 cells and increasing Treg cells in the rat brain, reducing the inflammatory response, and improving cerebral ischaemia-reperfusion injury. CONCLUSIONS: These data indicate that HQ-HH combination can improve ischaemic stroke by regulating the gut microbiota to affect bile acid metabolism, providing experimental evidence for the wide application of HQ-HH in clinical practice of ischaemic stroke.

Electrolyte Analysis in Blood Serum by Laser-Induced Breakdown Spectroscopy Using a Portable Laser.

The fast and reliable analysis of electrolytes such as K, Na, Ca in human blood serum has become an indispensable tool for diagnosing and preventing diseases. Laser-induced breakdown spectroscopy (LIBS) has been demonstrated as a powerful analytical technique on elements. To apply LIBS to the quantitative analysis of electrolyte elements in real time, a self-developed portable laser was used to measure blood serum samples supported by glass slides and filter paper in this work. The partial least squares regression (PLSR) method was employed for predicting the concentrations of K, Na, Ca from serum LIBS spectra. Great prediction accuracies with excellent linearity were obtained for the serum samples, both on glass slides and filter paper. For blood serum on glass slides, the prediction accuracies for K, Na, Ca were 1.45%, 0.61% and 3.80%. Moreover, for blood serum on filter paper, the corresponding prediction accuracies were 7.47%, 1.56% and 0.52%. The results show that LIBS using a portable laser with the assistance of PLSR can be used for accurate quantitative analysis of elements in blood serum in real time. This work reveals that the handheld LIBS instruments will be an excellent tool for real-time clinical practice.

Safety of denosumab versus zoledronic acid in the older adults with osteoporosis: a meta-analysis of cohort studies.

Denosumab is a newly approved treatment for osteoporosis in China. However, the clinical safety and advantages of denosumab have not been much established. The current study evaluates the real-world safety of denosumab versus zoledronic acid in treating cancer-free adults aged 50 years or older with osteoporosis to provide clinical settings guidelines. PURPOSE: A head-to-head comparison of the safety profiles between denosumab (60 mg subcutaneously every 6 months) and zoledronic acid (5 mg, intravenously yearly) was performed in cancer-free adults aged 50 years or older with osteoporosis. METHODS: MEDLINE, EMBASE, and Cochrane Library databases were searched for cohort studies comparing the safety of denosumab and zoledronic acid in cancer-free adults aged 50 years or older with osteoporosis till December 2021. The outcomes included the risk of fracture and other severe adverse events. Based on the Cochrane Handbook for Systematic Reviews of Interventions 5.0.2, we identified the eligible studies. RESULTS: Three cohort studies having 38,845 cancer-free adults aged 50 years or older were included in the study. The results showed that denosumab was not superior to zoledronic acid in reducing fracture risk [RR (95% CI): 1.05 (0.90, 1.23), P = 0.52]. However, denosumab had a low risk of composite cardiovascular disease [RR (95% CI): 0.82 (0.70, 0.96), P = 0.01]. There were no significant differences between the hazards of serious infection, and total adverse events (P > 0.05). CONCLUSION: The present meta-analysis demonstrated that for cancer-free adults aged 50 years or older with osteoporosis, denosumab was as safe as zoledronic acid for the risk of drug-induced fractures. However, denosumab had a lower incidence of composite cardiovascular disease, and may be a better option for the population with cardiovascular disease. Nonetheless, due to limitations like a short-term follow-up, gender, and incomplete types of adverse effects, more randomized controlled trials (RCTs) are required to further verify this conclusion.

Tetrahydrocurcumin Ameliorates Acute Hypobaric Hypoxia-Induced Cognitive Impairment in Mice.

Ma, Xuexinyu, Yang Pan, Yuye Xue, Yao Li, Yan Zhang, Yani Zhao, Xingzhao Xiong, Jianbo Wang, and Zhifu Yang. Tetrahydrocurcumin ameliorates acute hypobaric hypoxia-induced cognitive impairment in mice. High Alt Med Biol. 23:264-272, 2022. Background: Hypobaric hypoxia (HH) impairs spatial learning and increases oxidative stress in rodents. We hypothesized that tetrahydrocurcumin (THC) may attenuate HH-induced neurobehavioral deficits by reducing HH-induced lipid peroxidation and increasing glycolytic activity. Materials and Methods: A C57BL/6 mouse model of acute high altitude brain injury was established using an animal decompression chamber for 24 hours. Cognitive and behavioral assessments were conducted using the Y-maze, open field, and Rotarod tests. We measured superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity; malondialdehyde (MDA) and reactive oxygen species levels; anti-neuronal core antigen (NeuN) immunoreactivity; and active occludin, hypoxia-inducible factor-1α, glucose transporter 1 (GLUT1), and GLUT3 expression levels in mice brain tissue. Results: The mice in the THC group showed improved cognitive impairment compared with those in the HH group in cognitive and behavioral tests, but failed to show improvement in the decline in coordination. The mice in the THC group were more effected than those in the HH group in demonstrating alleviation of hyperemia in cortical vessels and cell voids, and cells in the CA1 region were more closely arranged. Compared with those in the mice of the HH group, the concentration of MDA decreased significantly, the expression of occludin, NeuN immunoreactivity, and the activities of SOD and GSH-Px significantly increased in the mice of the THC group. An increase in GLUT1 expression was observed in HH-exposed animals (N group vs. HH group: 0.4 ± 0.08 vs. 0.60 ± 0.07, p < 0.05), and this increase was enhanced in animals treated with THC (HH group vs. THC group: 0.60 ± 0.07 vs. 0.82 ± 0.08, p < 0.05). Conclusions: THC improved cognitive impairment in mice, accompanied by reduced oxidative stress and increased GLUT1 protein levels.

Huangqi-Honghua Combination Prevents Cerebral Infarction with Qi Deficiency and Blood Stasis Syndrome in Rats by the Autophagy Pathway.

BACKGROUND: Cerebral ischemia/reperfusion injury (CI/RI) contributes to the process of autophagy. Huangqi-Honghua combination (HQ-HH) is a traditional Chinese medicine (TCM) combination that has been widely used in the treatment of cerebrovascular diseases in China. The role of autophagy in HQ-HH-mediated treatment of CI/RI is unclear. METHODS: Sprague-Dawley (SD) rats were used to establish the middle cerebral artery occlusion (MCAO) with QDBS syndrome model and evaluate the function of HQ-HH in protecting against CI/RI. RESULTS: HQ-HH significantly improved the neuronal pathology and reduced infarct volume, neurological deficits, and whole blood viscosity in rats with CI/RI. Western blot results showed that the expression of autophagy marker proteins LC3II/LC3I and Beclin1 in the HQ-HH group was significantly lower than that in the model group, while the expression of p62 was significantly higher in the HQ-HH group as compared with the model group. There were no significant differences in PI3K, Akt, and mTOR levels between the HQ-HH group and the model group; however, p-PI3K, p-Akt, and p-mTOR were significantly upregulated. In addition, HQ-HH also changed the composition and function of intestinal flora in MCAO + QDBS model rats. CONCLUSION: HQ-HH protects from CI/RI, and its underlying mechanism may involve the activation of the PI3K-Akt-mTOR signaling pathway, relating to the changes in the composition of intestinal flora.

Network pharmacology-based prediction of the active compounds and mechanism of Buyang Huanwu Decoction for ischemic stroke.

Buyang Huanwu Decoction (BYHWD) is used to promote blood circulation and is widely used in Chinese clinical practice for the treatment and prevention of ischemic cerebral vascular diseases. However, the mechanism and active compounds of BYHWD used to treat ischemic stroke are not well understood. The current study aimed to identify the potential active components of BYHWD and explore its mechanism using network pharmacology and bioinformatics analyses. The compounds of BYHWD were obtained from public databases. Oral bioavailability and drug-likeness were screened using the absorption, distribution, metabolism and excretion (ADME) criteria. Components of BYHWD, alongside the candidate targets of each component and the known therapeutic targets of ischemic stroke were collected. A network of target gene compounds and cerebral ischemia compounds was established using network pharmacology data sources. The enrichment of key targets and pathways was analyzed using STRING and DAVID databases. Moreover, three of key targets [IL6, VEGFA and hypoxia-inducible-factor-1α (HIF-1α)] were verified using western blot analysis. Network analysis determined 102 compounds in seven herbal medicines that were subjected to ADME screening. A total of 42 compounds as well as 79 genes formed the principal pathways associated with ischemic stroke. The 16 key compounds identified were baicalein, beta-carotene, baicalin, kaempferol, luteolin, quercetin, hydroxysafflor yellow A, isorhamnetin, bifendate, formononetin, calycosin, astragaloside IV, stigmasterol, sitosterol, Z-ligustilide, and dihydrocapsaicin. The core genes in this network were IL6, TNF, VEGFA, HIF-1α, MAPK1, MAPK3, JUN, STAT3, IL1B and IL10. Furthermore, the TNF, IL17, apoptosis, PI3K-Akt, toll-like receptor, MAPK, NF-κB and HIF-1 signaling pathways were identified to be associated with ischemic stroke. Compared with the control group (no treatment), BYHWD significantly inhibited the expression of IL6 and increase the expression of HIF-1α and VEGFA. Network pharmacology analyses can help to reveal close interactions between multi-components and multi-targets and enhance understanding of the potential effects of BYHWD on ischemic stroke.

A Network Pharmacology Approach to Predict the Proangiogenesis Mechanism of Huangqi-Honghua Herb Pair after Cerebral Ischemia.

OBJECTIVE: Huangqi-Honghua herb pair is known for its medicinal value to treat Qi deficiency and blood stasis syndrome with a long history in clinical practice. To understand its possible mechanism in a systematic study, a network pharmacological method was addressed. METHODS: Detailed information on the HH compounds was obtained from two public databases, and oral bioavailability (OB) and drug-like (DL) of the compounds were evaluated. A correlation between HH compounds, its potential targets, and known targets was extrapolated, and the herb-compound-target-disease (H-C-T-D) network was established. Next, the pathway enrichment and essential genes were analyzed. Then, three key genes (VEGFA, VEGFR2, and eNOS), highly associated with angiogenesis, were screened and verified through western blot assay. RESULTS: Out of 276 compounds, 21 HH compounds and 78 target genes regulating the major pathways associated with CI in the network are analyzed. The bioactive compounds in HH were active in various signal transduction pathways such as the toll-like receptor signaling pathway, VEGF signaling pathway, TNF signaling pathway, and HIF-1 signaling pathway are important pathways that may regulate anti-inflammatory, antiapoptotic, immune correlation, and antioxidative effects. The core genes are PTGS2, TNF, NOS2, IL6, BCL2, IL1B, SOD2, NOS3, SOD1, MMP9, and VEGFA. The in vitro results suggested that HH treatment could significantly elevate the expression of proangiogenic genes such as VEGFA, VEGFR2, and eNOS compared with OGD groups. CONCLUSIONS: Our results predict that HH may regulate the expression of VEGFA, VEGFR2, and eNOS via the VEGF and HIF-1 signaling pathway to promote angiogenesis and alleviate cerebral ischemia injury.

Astragaloside and/or Hydroxysafflor Yellow A Attenuates Oxygen-Glucose Deprivation-Induced Cultured Brain Microvessel Endothelial Cell Death through Downregulation of PHLPP-1.

The incidence of ischemic stroke, a life-threatening condition in humans, amongst Asians is high and the prognosis is poor. In the absence of effective therapeutics, traditional Chinese medicines have been used that have shown promising results. It is crucial to identify traditional Chinese medicine formulas that protect the blood-brain barrier, which is damaged by an ischemic stroke. In this study, we aimed to elucidate such formulas. Brain microvascular endothelial cells (BMECs) were used to establish an in vitro ischemia-reperfusion model for oxygen-glucose deprivation (OGD) experiments to evaluate the function of two traditional Chinese medicines, namely, astragaloside (AS-IV) and hydroxysafflor yellow A (HSYA), in protecting against BMEC. Our results revealed that AS-IV and HSYA attenuated the cell loss caused by OGD by increasing cell proliferation and inhibiting cell apoptosis. In addition, these compounds promoted the migration and invasion of BMECs in vitro. Furthermore, we found that BMECs rescued by AS-IV and HSYA could be functionally activated in vitro, with AS-IV and HSYA showing synergetic effects in rescuing BMECs survival in vitro by reducing the expression of PHLPP-1 and activating Akt signaling. Our results elucidated the potential of AS-IV and HSYA in the prevention and treatment of stroke by protecting against cerebral ischemia-reperfusion injury.

Degradation, adsorption and leaching of phenazine-1-carboxamide in agricultural soils.

Phenazines, a large group of nitrogen-containing heterocycles with promising bioactivities, can be widely used as medicines and pesticides. But phenazines also generate toxicity risks due to their non-selective DNA binding. The environmental fate of phenazines in soils is the key to assess their risks; however, hitherto, there have been very few related studies. Therefore in the present study, the degradation, adsorption and leaching behaviors of a typical natural phenazine-phenazine-1-carboxamide (PCN) in agricultural soils from three representative places in China with different physicochemical properties were, for the first time, systematically studied in laboratory simulation experiments. Our results indicated that the degradation of PCN in all the tested soils followed the first order kinetics, with half-lives ranging from 14.4 to 57.8 d under different conditions. Soil anaerobic microorganisms, organic matter content and pH conditions are important factors that regulating PCN degradation. The adsorption data of PCN were found to be well fitted using the Freundlich model, with the r2 values above 0.978. Freundlich adsorption coefficient Kf of PCN ranged from 5.75 to 12.8 [(mg/kg)/(mg/L)1/n] in soils. The retention factor Rf values ranged from 0.0833 to 0.354, which means that the mobility of PCN in the three types of soil is between immobile to moderately mobile. Our results demonstrate that PCN is easily degraded, has high adsorption affinity and low mobility in high organic matter content and clay soils, thus resulting in lower risks of contamination to groundwater systems. In contrast, it degraded slowly, has low adsorption affinity and moderately mobile in soils with low organic matter and clay content, therefore it has higher polluting potential to groundwater systems. Overall, these findings provide useful insights into the future evaluation of environmental as well as health risks of PCN.

PP9, a steroidal saponin, induces G2/M arrest and apoptosis in human colorectal cancer cells by inhibiting the PI3K/Akt/GSK3ß pathway.

Colorectal cancer (CRC) represents one of the commonest malignancies around the world. PP9, a natural steroidal saponin, was firstly isolated from the rhizomes of Paris polyphylla var. latifolia. However, the therapeutic effects of PP9 on CRC and the underlying molecular mechanism remain undefined. Here, we demonstrated that treatment with PP9 time- and dose-dependently inhibited HT-29 and HCT116 cells without significantly inhibiting normal NCM460 cells. Furthermore, our results indicated that PP9 effectively induced G2/M phase arrest by upregulating p21 and suppressing cdc25C, Cyclin B1 and cdc2. Meanwhile, PP9 upregulated cleaved Caspase 3, cleaved Caspase 9 and cleaved PARP and Bax, while downregulating Bcl-2 to stimulate cell apoptosis. Mechanistically, PP9-suppressed PI3K/Akt/GSK3ß signaling, while the PI3K inhibitor LY294002 augmented PP9-mediated apoptosis, G2/M arrest and effects on PI3K/Akt/GSK3ß related proteins. Finally, we showed that PP9 (10 mg/kg) significantly reduced tumor growth in nude mouse CRC xenografts, more potently than 5-Fu (20 mg/kg). Jointly, these data firstly demonstrated that PP9 promotes G2/M arrest and apoptotic death in CRC cells through PI3K/Akt/GSK3ß signaling suppression, suggesting that PP9 could be considered a new and promising candidate for CRC therapy.

Neuroprotection of hydroxysafflor yellow A in experimental cerebral ischemia/reperfusion injury via metabolic inhibition of phenylalanine and mitochondrial biogenesis.

Stroke is the second most frequent cause of mortality, resulting in a huge societal burden worldwide. Timely reperfusion is the most effective therapy; however, it is difficult to prevent ischemia/reperfusion (I/R) injury. In traditional Chinese medicine, hydroxysafflor yellow A (HSYA) has been widely used for the treatment of cerebrovascular disease and as a protective therapy against I/R injury. Evidence has demonstrated that HSYA could reduce the levels of reactive oxygen species and suppress cellular apoptosis; however, whether HSYA alters the metabolic profile as its underlying mechanism for neuroprotection remains unknown. In the present study, using a metabolomic screening, phenylalanine was identified to significantly increase in an experimental model of mouse cerebral I/R injury. Notably, western blotting and qPCR analysis were conducted to test the expression level of apoptosis­associated factors, and HSYA was identified to be able to protect neuronal cells by reducing phenylalanine level associated with I/R injury. Additionally, these findings were confirmed in primary mouse neurons and PC12 cells exposed to oxygen and glucose deprivation/reoxygenation (OGD/R) stress. Of note, HSYA was observed to regulate the mRNA expression of key metabolic enzymes, phenylalanine hydroxylase, tyrosine aminotransferase and aspartate aminotransferase, which are responsible for phenylalanine metabolism. Furthermore, by performing mitochondrial labeling and JC­1 fluorescence assay, HSYA was identified to promote mitochondrial function and biogenesis suppressed by OGD/R. The findings of the present study demonstrated that I/R injury could increase the levels of phenylalanine, and HSYA may inhibit phenylalanine synthesis to enhance mitochondrial function and biogenesis for neuroprotection. The present study proposed a novel metabolite biomarker for cerebral I/R injury and the evaluated the efficacy of HSYA as a potential therapeutic treatment I/R injury.

Neuroprotective effect of Apelin 13 on ischemic stroke by activating AMPK/GSK-3ß/Nrf2 signaling.

BACKGROUND: Previous studies had showed that Apelin 13 could protect against apoptosis induced by ischemic/reperfusion (I/R). However, the mechanisms whereby Apelin 13 protected brain I/R remained to be elucidated. The present study was designed to determine whether Apelin 13 provided protection through AMPK/GSK-3ß/Nrf2 pathway. METHODS: In vivo, the I/R model was induced and Apelin 13 was given intracerebroventricularly 15 min before reperfusion. The neurobehavioral scores, infarction volumes, and some cytokines in the brain were measured. For in vitro study, PC12 cells were used. To clarify the mechanisms, proteases inhibitors or siRNA were used. Protein levels were investigated by western blotting. RESULTS: The results showed that Apelin 13 treatment significantly reduced infarct size, improved neurological outcomes, decreased brain edema, and inhibited cell apoptosis, oxidative stress, and neuroinflammation after I/R. Apelin 13 significantly increased the expression of Nrf2 and the phosphorylation levels of AMPK and GSK-3ß. Furthermore, in cultured PC12 cells, the same protective effects were also observed. Silencing Nrf2 gene with its siRNA abolished the Apelin 13's prevention of I/R-induced PC12 cell injury, oxidative stress, and inflammation. Inhibition of AMPK by its siRNA decreased the level of Apelin 13-induced Nrf2 expression and diminished the protective effects of Apelin 13. The interplay relationship between GSK-3ß and Nrf2 was also verified with relative overexpression. Using selective inhibitors, we further identified the upstream of AMPK/GSK-3ß/Nrf2 is AR/Gα/PLC/IP3/CaMKK. CONCLUSIONS: In conclusion, the previous results showed that Apelin 13 protected against I/R-induced ROS-mediated inflammation and oxidative stress through activating the AMPK/GSK-3ß pathway by AR/Gα/PLC/IP3/CaMKK signaling, and further upregulated the expression of Nrf2-regulated antioxidant enzymes.

Proteomic Analysis of Hydroxysafflor Yellow A Against Cerebral Ischemia/Reperfusion Injury in Rats.

Hydroxysafflor yellow A (HSYA), an active component from Chinese medicinal herb, has been applied to the prevention and treatment of cerebral ischemia/reperfusion injury (CIRI). To clarify the comprehensive mechanisms HSYA for stroke, we used label-free quantitative proteomic analysis to investigate the modulated proteins of rats subjected to CIRI and their alteration by HSYA. Neurological examination, infarct assessment, and biochemical assay were performed to validate the effects of HSYA, and the results indicated that HSYA played a significant role in brain protection. A total of 13 proteins were identified as overlapped proteins by label-free quantitative proteomic analysis. Gene Ontology and pathway analysis showed that these differentially expressed proteins were mainly enriched in the hypoxia-inducible factor 1 (HIF-1) signaling pathway. Furthermore, networks were constructed with respect to protein function interactions. The results suggested that seven proteins were identified as hub proteins between model and sham groups, while 25 proteins were identified as hub proteins between HSYA and model groups. In addition, the expressions of three overlapping proteins were validated by Western blot, and their levels were consistent with the results of label-free analysis. In conclusion, Eftud2, mTOR, Rab11, Ppp2r5e, and HIF-1 signaling pathways have been detected as key hub proteins and pathways in HSYA against CIRI through proteomic analysis. Our research has provided convincing explanations for the mechanism of HSYA against CIRI and the identified key proteins and pathways might provide novel therapeutics for CIRI.