Effective enrichment of trace exosomes for the label-free SERS detection via low-cost thermophoretic profiling.

Exosome-based liquid biopsies possess great potential in monitoring cancer development However, current exosome detection biosensors require large exosome volumes, showing the weak detection sensitivity. Besides, these methods pay little attention to in situ analysis of exosomes, hence limiting the provision of more accurate clinically-relevant information. Herein, we develop an innovative label-free biosensor combining the low-cost thermophoretic enrichment method with the surface-enhanced Raman spectroscopy (SERS) detection. Based on the thermophoretic enrichment strategy, exosomes and gold nanoparticles can be enriched together into a small area with a scale of 500 µm within 10 min. The Raman signals of various exosomes derived from normal, cancerous cell lines and human serum are dynamically monitored in situ, with the limit of detection of 102-103 particles per microliter, presenting higher sensitivity compared with the similar label-free SERS detection. The spectral data set of different exosomes is applied to train for multivariate classification of cell types and to estimate how the normal exosome data resemble cancer cell exosome. The reliable classification and identification of different exosomes can be realized. The current biosensor is convenient, low-cost and requires small exosome volumes (∼3 µL), and if validated in larger cohorts may contribute to the tumor prediction and diagnosis.

Solution-Based SERS Detection of Weak Surficial Affinity Molecules Using Cysteamine-Modified Au Bipyramids.

To achieve ultrasensitive detection of trace targets through solution-based surface-enhanced Raman spectroscopy (SERS), direct adsorption of the target molecules on a SERS-active surface is vital. In this work, cetyltrimethylammonium bromide (CTAB)-capped gold nano-bipyramids (Au BPs) with different aspect ratios (ARs) are prepared and the surface is successfully modified by a simple ligand exchange method. Cysteamine-capped gold nano-bipyramids (cyst-Au BPs) are obtained by means of replacement of CTAB by cysteamine using Au-S covalent bonding and applied in the solution-based SERS detection of different pigment molecules, which always have weak affinity to the gold surface. The hydrogen bonding between the pigment molecule and cysteamine causes the aggregation of Au BPs to generate local electromagnetic field enhancement. The influence of the AR and concentration of Au BPs on SERS properties is investigated. The SERS detection of weak-affinity molecules to an extremely low limit shows that the cyst-Au BPs are highly sensitive compared to CTAB-capped Au BPs. The limit of detection (LOD) of allura red as low as 0.1 ppb and that of sunset yellow as low as 1 ppb show that the proposed strategy has many advantages due to its simplicity and fast and rapid detection for the sensitivity analysis of weak-affinity molecules.

Clinical value of serum Ape1/Ref-1 combined with TGF-ß1 monitoring in predicting the occurrence of radiation pneumonitis (RP) in non-small cell lung cancer patients.

BACKGROUND: The aim of the present study was to explore the predictive value of serum apurinic/apyrimidinic endonuclease 1/redox factor-1 (Ape1/Ref-1) combined with transforming growth factor ß1 (TGF-ß1) levels in the occurrence of radiation pneumonitis (RP) in patients with non-small cell lung cancer (NSCLS). METHODS: Eighty-one patients with NSCLS who were admitted from August 2017 to July 2019 were enrolled in the present study. All patients were treated with concurrent radiotherapy and chemotherapy. Serum Ape1/Ref-1 and TGF-ß1 levels were measured before treatment and 12 weeks after treatment. Patients with radiation-induced lung injury were assessed and divided into the RP group (lung injury ≥2) and non-RP (NRP) group (grade <2). The levels of serum Ape1/Ref-1 and TGF-ß1 before and after treatment between the 2 groups were compared. The relationship between clinical characteristics, serum Ape1/Ref-1, TGF-ß1 levels, and the occurrence of RP were then analyzed, and the relationship between serum Ape1/Ref-1, TGF-ß1 levels, and their predictive value for the occurrence of RP was also assessed. RESULTS: The incidence of RP in 81 patients was 30.86%. After treatment, the serum Ape1/Ref-1 and TGF-ß1 levels of the 2 groups were significantly higher than those before treatment (P<0.05). Furthermore, after treatment, the levels of serum Ape1/Ref-1 and TGF-ß1 in the RP group were significantly higher than those of the NRP group (P<0.05). Multivariate logistic regression analysis showed that V20, Ape1/Ref-1, and TGF-ß1 were associated with the occurrence of RP (P<0.05). The levels of serum Ape1/Ref-1 were positively correlated with TGF-ß1 (r=0.734, P<0.05). Finally, the area under the curve of RP occurrence, which was predicted by the levels of serum Ape1/Ref-1, TGF-ß1, and the combination of both were 0.779, 0.69, and 0.842, respectively. CONCLUSIONS: The occurrence of RP in NSCLS patients is closely related to the levels of serum Ape1/Ref-1 and TGF-ß1, and the combination of both has important predictive values for the occurrence of RP.

Rosmarinic acid ameliorated cardiac dysfunction and mitochondrial injury in diabetic cardiomyopathy mice via activation of the SIRT1/PGC-1α pathway.

Mitochondrial injury plays an essential role in the pathogenesis of diabetic cardiomyopathy (DCM). Previous studies demonstrated that rosmarinic acid (RA) treatment prevented high glucose-induced mitochondrial injury in vitro. However, whether RA can ameliorate cardiac function by preventing mitochondrial injury in DCM is unknown. The SIRT1/PGC-1α pathway has emerged as an important regulator of metabolic control and other mitochondrial functions. The present study was undertaken to determine the effects of RA on mitochondrial and cardiac function in DCM as well as the involvement of the SIRT1/PGC-1α pathway. Our results revealed that RA improved cardiac systolic and diastolic function and prevented mitochondrial injury in DCM, as shown by the reduced blood glucose and lipid levels, increased mitochondrial membrane potential levels, improved adenosine triphosphate synthesis, and inhibited apoptosis (P < 0.05). Moreover, RA upregulated the expression of SIRT1 and PGC-1α in DCM mice and high glucose-treated H9c2 cardiomyocytes (P < 0.05). Further mechanistic studies in H9c2 cardiomyocytes revealed that suppression of SIRT1 by Sh-SIRT1 counteracted the effects of RA on high glucose-induced abnormal metabolism of glucose and lipids, oxidative stress and apoptosis (P < 0.05). Taken together, these data indicate that RA prevented mitochondrial injury and cardiac dysfunction in DCM mice, and the SIRT1/PGC-1α pathway mediated the protective effects of RA.

Mesoporous gold nanoparticles for photothermal controlled anticancer drug delivery.

Aim: To realize the transit and release of cancer drug exactly as well as high drug loading ratio, we reported a biocompatible and temperature responsive controlled drug delivery system based on 3D mesoporous structured Au networks. Materials & methods: Here, we filled the hollow interiors of Au networks with a phase-change material so that the drug release was easily regulated by controlling the temperature only. Results: Thanks to the high near-infrared reflectance absorbance and mesoporous structure, the Au-PEG + lauric acid/doxorubicin system showed a strong photothermal conversion efficiency, high drug-loading ratio (54.2% for doxorubicin) and controlled drug release. Conclusion: This system revealed great advantages in photothermal therapy and chemotherapy, offering an obvious synergistic effect in cancer treatment.

IFN-γ aggravates neointimal hyperplasia by inducing endoplasmic reticulum stress and apoptosis in macrophages by promoting ubiquitin-dependent liver X receptor-α degradation.

Neointimal hyperplasia is the main cause of restenosis after percutaneous coronary interventions (PCIs). Both IFN-γ and macrophages play nonredundant roles in the pathogenesis of vascular intimal hyperplasia; however, the underlying mechanisms remain elusive and must be further investigated. In mouse peritoneal macrophages, IFN-γ significantly accelerated degradation and up-regulated polyubiquitination of liver X receptor (LXR)-α. Signal transducer and activator of transcription 1 (STAT1) inhibitor, fludarabine, and PIAS1 knockdown reduced ubiquitination and increased the expression of LXR-α in IFN-γ-treated macrophages. IFN-γ also increased the expression of endoplasmic reticulum (ER) stress-related proteins, including p-PERK, p-eIIF2α, and CCAAT-enhancer-binding protein homologous protein (CHOP), as well as apoptosis of macrophages. Treatment with ER stress inhibitor, 4-phenylbutyric acid (4-PBA), and LXR agonist, T0901317 (T0), alleviated IFN-γ-induced apoptosis in macrophages. Neointimal hyperplasia was significant after carotid ligation for 4 wk in ApoE-/- mice. IFN-γ mAb, T0, and 4-PBA treatment not only significantly attenuated neointimal hyperplasia but also decreased CD68+TUNEL+ double-positive macrophages in the hyperplastic neointima. Moreover, after 4-PBA or T0 administration, the number of CD68+p-eIIF2α+ and CD68+CHOP+ double-positive cells in neointimal was also apparently decreased. Taken together, these results defined an unexpected role of IFN-γ and LXR-α in the development of neointimal hyperplasia. The PIAS1/STAT1-dependent LXR-α degradation induced by IFN-γ promoted ER stress and apoptosis in macrophages, which leads to aggravated neointimal hyperplasia. LXR agonist efficiently improved neointimal hyperplasia, which may be a promising new strategy to ameliorate restenosis and vascular remodeling after PCI.-Zhao, Q., Zhou, D., You, H., Lou, B., Zhang, Y., Tian, Y., Guo, N., Chen, X., Liu, Y., Wu, Y., Yuan, Z., Zhou, J. IFN-γ aggravates neointimal hyperplasia by inducing endoplasmic reticulum stress and apoptosis in macrophages by promoting ubiquitin-dependent liver X receptor-α degradation.