A portable test strip fabricated of luminescent lanthanide-functionalized metal-organic frameworks for rapid and visual detection of tetracycline antibiotics.

Tetracycline antibiotics (TCs) are commonly used antibiotics in the treatment of infections, but their overuse has a negative impact on human health and ecosystems. Thus, the development of a facile and on-site visualization method for TC detection is necessary. Here, we propose the potential of using lanthanide-functionalized metal-organic framework (MOF) composites (Ag+/Tb3+@UiO-66-(COOH)2, ATUC) as a probe for the rapid detection of tetracycline (TC), chlortetracycline (CTC), oxytetracycline (OTC), and doxycycline (DOX) residues, in which UiO-66-(COOH)2 (UC) could be utilized to provide an interaction microenvironment, Tb3+ as recognition units and Ag+ as a fluorescence enhancer. Upon exposure to TCs, significant luminescence quenching of ATUC excited at 255 nm was observed due to the inner filter effect (IFE) and photo-induced electron transfer (PET), and the established strategy has a detection limit (LOD) of 11.0, 20.1, 9.1, and 22.5 nM for TC, CTC, OTC, and DOX, respectively. More importantly, given its portability and conspicuous luminescence color gradation variation, a portable test strip based on ATUC was manufactured and the results could be distinguished immediately by the naked eye and smartphone analysis, allowing for on-site rapid quantitative assay of TCs, not only in the laboratory but also in a point-of-care setting.

Beneficial effects of Huaiqihuang on hyperglycemia-induced MPC5 podocyte dysfunction through the suppression of mitochondrial dysfunction and endoplasmic reticulum stress.

The present study was performed to investigate the effect of Huaiqihuang (HQH) on hyperglycemia (HG)-induced mitochondrial dysfunction and endoplasmic reticulum (ER) stress in MPC5 podocytes. The effects of HQH and HG on cell viability were assessed using an MTT assay. mRNA and protein expression levels were evaluated using reverse transcription-quantitative polymerase chain reaction and western blot analysis, respectively. Cell apoptosis was assessed using terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling, whereas reactive oxygen species production and alterations in mitochondrial membrane potential were assessed using flow cytometry. DNA damage was evaluated using a comet assay. The results demonstrated that treatment of podocytes with HQH markedly suppressed the HG­induced generation of reactive oxygen species. HQH also significantly improved mitochondrial membrane potential in podocytes exposed to HG. When the podocytes were treated with HG, Ca2+ levels were significantly increased, compared with those in the control group, whereas treatment of the podocytes with HQH significantly reversed the HG­induced upregulation of Ca2+ secretion. Treatment of the podocytes with HQH significantly reversed the HG­induced upregulation of glucose­related protein 78 (GRP78) and C/EBP­homologous protein, which were used as indicators of ER stress. Furthermore, GRP78 loss­of­function attenuated HG­induced podocyte dysfunction, including cell apoptosis and DNA damage. In conclusion, beneficial effects of HQH on HG­induced MPC5 podocyte dysfunction were observed, and occurred through the suppression of mitochondrial dysfunction and ER stress.

Huaiqihuang may protect from proteinuria by resisting MPC5 podocyte damage via targeting p-ERK/CHOP pathway.

The purpose of this study was to investigate the potential effects of Huaiqihuang (HQH) granule, a Chinese herbal medicine, in treating proteinuria and to reveal its possible mechanism. MPC5 podocytes were cultured in vitro at 37°C and induced with tunicamycin (TM). The TM-induced cells were treated with HQH at different concentrations. The cell proliferation was detected using the MTT assay. The optimal effective dose of HQH for MPC5 cells was determined by the MTT assay and LDH assay respectively. The influences of HQH on the proteinuria-related protein expression and the signaling pathway associated protein expression were also detected using quantitative reverse transcription PCR and Western blotting analysis. The results showed that the MPC5 cell model was successfully constructed in vitro. The HQH application could improve the harmful effects induced by TM on the MPC5 cells, including promoted cell proliferation and suppressed cell apoptosis. Furthermore, the protein expression, including podocin, nephrin, and synaptopodin was down-regulated by the TM treatment in the MPC5 cells. On contrary, the expression of these proteins was up-regulated after the HQH application. Also, the effect of TM on integrin α3 and integrin ß1 expressions was also reversed by the HQH treatment. Moreover, the HQH application decreased the expression of p-ERK and DNA-damage-inducible transcript 3 (DDIT3 or CHOP) in the MPC5 cells, which was opposite to the effect observed in the cells treated with TM. Taken together, our study suggest that HQH application may protect podocytes from TM damage by suppressing the p-ERK/CHOP signaling pathway.