BACKGROUND AND OBJECTIVES

Acute kidney injury (AKI) is a common complication of critical illness that often leads to increased mortality and morbidity. Biomarkers detect AKI earlier, providing a window of opportunity for timely intervention. Of the recent biomarkers in literature, the cell cycle arrest biomarkers tissue inhibitor of metalloproteinases-2 (TIMP-2) and insulin-like growth factor binding protein-7 (IGFBP-7) were found to be superior in predicting AKI. Our study aimed to evaluate the diagnostic performance of urine TIMP-2/IGFBP-7 in its ability to predict AKI and major adverse kidney events within 30 days (MAKE30) among high-risk patients for AKI. MAKE30 is a composite outcome comprised of all-cause mortality, use of renal replacement therapy (RRT), or persistent renal dysfunction at hospital discharge truncated at 30 days.

We conducted a prospective, cross-sectional study which included 135 adult, non-COVID ICU patients. Baseline urine TIMP-2/IGFBP-7 results were used to dichotomize the population into low risk (< 0.3 ng/mL) or high risk (≥ 0.3 ng/mL) for AKI. Participants were then observed for 30 days and monitored for MAKE30 outcomes. ROC curves were created to calculate the sensitivity, specificity, NPV, PPV, and the AUC of the 0.3 ng/mL cut-off to predict the AKI and MAKE30.

Urine TIMP-2/IGFBP-7 cutoff of 0.3 ng/mL predicted AKI with a sensitivity of 82.4%, specificity of 79.2%, PPV of 57.1%, NPV of 93% and AUC of 0.81. MAKE30 was detected with a sensitivity of 62.8%, specificity of 76.1%, PPV of 55.1%, NPV of 81.4% and AUC of 0.69. Elevated levels of urine TIMP-2/IGFBP-7 were found to be associated with AKI (p <0.01), MAKE30 (p <0.01) and all of its subcomponents. Survival or discharge after 30 days were found to be associated with lower urine TIMP-2/IGFBP-7 levels (p <0.01).

Urine TIMP-2/IGFBP-7, at its current cutoff at 0.3 ng/mL, can predict the likelihood of developing AKI and major adverse kidney events among high-risk patients for AKI. It can serve as a useful adjunct to existing methods, such as serum creatinine, in the early diagnosis and prognosis of acute kidney injury and expanding the therapeutic window to prevent disease progression and improve outcomes.

The multiple-step cleavage of amyloid precursor protein (APP) generates amyloid-β peptides (Aβ), highly toxic molecules causing Alzheimer's disease (AD). The nonspecific cleavage between the transmembrane region of APP (APPTM) and γ-secretase is the key step of Aβ generation. Reconstituting APPTM under physiologically-relevant conditions is crucial to investigate how it interacts with γ-secretase and for future AD drug discovery. Although producing recombinant APPTM was reported before, the large scale purification was hindered by the use of biological protease in the presence of membrane protein. Here, we expressed recombinant APPTM in Escherichia coli using the pMM-LR6 vector and recovered the fusion protein from inclusion bodies. By combining Ni-NTA chromatography, cyanogen bromide cleavage, and reverse phase high performance liquid chromatography (RP-HPLC), isotopically-labeled APPTM was obtained in high yield and high purity. The reconstitution of APPTM into dodecylphosphocholine (DPC) micelle generated mono dispersed 2D ¹⁵N-¹H HSQC spectra in high quality. We successfully established an efficient and reliable method for the expression, purification and reconstruction of APPTM, which may facilitate future investigation of APPTM and its complex in more native like membrane mimetics such as bicelle and nanodiscs.
Humans ; Amyloid beta-Protein Precursor/chemistry* ; Micelles ; Amyloid Precursor Protein Secretases/metabolism* ; Magnetic Resonance Spectroscopy ; Recombinant Proteins

Silent information regulator 1 (SIRT1) is one of the seven mammalian proteins of the sirtuin family of NAD⁺-dependent deacetylases. SIRT1 plays a pivotal role in neuroprotection and ongoing research has uncovered a mechanism by which SIRT1 may exert a neuroprotective effect on Alzheimer's disease (AD). Growing evidence demonstrates that SIRT1 regulates many pathological processes including amyloid-β precursor protein (APP) processing, neuroinflammation, neurodegeneration, and mitochondrial dysfunction. SIRT1 has recently received enormous attention, and pharmacological or transgenic approaches to activate the sirtuin pathway have shown promising results in the experimental models of AD. In the present review, we delineate the role of SIRT1 in AD from a disease-centered perspective and provides an up-to-date overview of the SIRT1 modulators and their potential as effective therapeutics in AD.
Animals ; Alzheimer Disease ; Amyloid beta-Protein Precursor ; Animals, Genetically Modified ; Sirtuin 1 ; Sirtuins ; Humans

OBJECTIVES: The phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway is one of the main signaling pathways related to autophagy. Autophagy plays a key role in the formation of silicosis fibrosis. The phenotypic transformation of lung fibroblasts into myofibroblasts is a hallmark of the transition from the inflammatory phase to the fibrotic phase in silicosis. This study aims to investigate whether the PI3K/Akt/mTOR pathway affects the phenotypic transformation of silicosis-induced lung fibroblasts into myofibroblasts via mediating macrophage autophagy. METHODS: The human monocytic leukemia cell line THP-1 cells were differentiated into macrophages by treating with 100 ng/mL of phorbol ester for 24 h. Macrophages were exposed to different concentrations (0, 25, 50, 100, 200, 400 μg/mL) and different times (0, 6, 12, 24, 48 h) of SiO₂ dust suspension. The survival rate of macrophages was measured by cell counting kit-8 (CCK-8) method. Enzyme linked immunosorbent assay (ELISA) was used to measure the contents of transforming growth factor-β1 (TGF-β1) and tumor necrosis factor-α (TNF-α) in the cell supernatant. The co-culture system of macrophages and HFL-1 cells was established by transwell. A blank control group, a SiO₂ group, a LY294002 group, a SC79 group, a LY294002+SiO₂ group, and a SC79+SiO₂ group were set up in this experiment. Macrophages in the LY294002+SiO₂ group were pretreated with LY294002 (PI3K inhibitor) for 18 hours, and macrophages in the SC79+SiO₂ group were pretreated with SC79 (Akt activator) for 24 hours, and then exposed to SiO₂ (100 μg/mL) dust suspension for 12 hours. The expression of microtubule-associated protein 1 light chain 3 (LC3) protein in macrophages was detected by the immunofluorescence method. The protein expressions of PI3K, Akt, mTOR, Beclin-1, LC3 in macrophages, and collagen III (Col III), α-smooth muscle actin (α-SMA), fibronectin (FN), matrix metalloproteinase-1 (MMP-1), tissue metalloproteinase inhibitor-1 (TIMP-1) in HFL-1 cells were measured by Western blotting. RESULTS: After the macrophages were exposed to SiO₂ dust suspension of different concentrations for 12 h, the survival rates of macrophages were gradually decreased with the increase of SiO₂ concentration. Compared with the 0 μg/mL group, the survival rates of macrophages in the 100, 200, and 400 μg/mL groups were significantly decreased, and the concentrations of TGF-β1 and TNF-α in the cell supernatant were obviously increased (all P<0.05). When 100 μg/mL SiO₂ dust suspension was applied to macrophages, the survival rates of macrophages were decreased with the prolonged exposure time. Compared with the 0 h group, the survival rates of macrophages were significantly decreased (all P<0.05), the concentrations of TGF-β1 and TNF-α in the cell supernatant were significantly increased, and the protein expression levels of Beclin-1 and LC3II were increased markedly in the 6, 12, 24, and 48 h groups (all P<0.05). Immunofluorescence results demonstrated that after exposure to SiO₂ (100 μg/mL) dust for 12 h, LC3 exhibited punctate aggregation and significantly higher fluorescence intensity compared to the blank control group (P<0.05). Compared with the blank control group, the protein expressions of Col III, FN, α-SMA, MMP-1, and TIMP-1 in HFL-1 cells were up-regulated in the SiO₂ group (all P<0.05). Compared with the SiO₂ group, the protein expressions of PI3K, Akt, and mTOR were down-regulated and the protein expressions of LC3II and Beclin-1 were up-regulated in macrophages (all P<0.05), the contents of TNF-α and TGF-β1 in the cell supernatant were decreased (both P<0.01), and the protein expressions of Col III, FN, α-SMA, MMP-1, and TIMP-1 in HFL-1 cells were down-regulated (all P<0.05) in the LY294002+SiO₂ group. Compared with the SiO₂ group, the protein expressions of PI3K, Akt, and mTOR were up-regulated and the protein expressions of LC3II and Beclin-1 were down-regulated in macrophages (all P<0.05), the contents of TNF-α and TGF-β1 in the cell supernatant were increased (both P<0.01), and the protein expressions of Col III, FN, α-SMA, MMP-1, and TIMP-1 in HFL-1 cells were up-regulated (all P<0.05) in the SC79+SiO₂ group. CONCLUSIONS Silica dust exposure inhibits the PI3K/Akt/mTOR pathway, increases autophagy and concentration of inflammatory factors in macrophages, and promotes the phenotype transformation of HFL-1 cells into myofibroblasts. The regulation of the PI3K/Akt/mTOR pathway can affect the autophagy induction and the concentration of inflammatory factors of macrophages by silica dust exposure, and then affect the phenotype transformation of HFL-1 cells into myofibroblasts induced by silica dust exposure.
Humans ; Proto-Oncogene Proteins c-akt/metabolism* ; Transforming Growth Factor beta1/metabolism* ; Silicon Dioxide/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Matrix Metalloproteinase 1/metabolism* ; Tissue Inhibitor of Metalloproteinase-1 ; Sirolimus ; Beclin-1/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Dust ; TOR Serine-Threonine Kinases/metabolism* ; Lung/metabolism* ; Fibroblasts/metabolism* ; Silicosis/metabolism* ; Macrophages/metabolism* ; Autophagy

OBJECTIVE: To investigate the clinical efficacy of the combined application of blistering cupping with thunder-fire moxibustion in treating bronchial asthma of cold-wheezing syndrome, and its influences on airway remodeling, inflammatory factors, lung function, and quality of life on the base of conventional western medicine treatment. METHODS: A total of 76 patients with bronchial asthma of cold-wheezing syndrome were randomly divided into an observation group and a control group, 38 cases in each group. In the control group, the basic treatment was used, i.e. budesonide formoterol powder inhalation. In the observation group, on the basis of the treatment as the control group, blistering cupping combined with thunder-fire moxibustion was supplemented, Dazhui (GV 14), Danzhong (CV 17) and bilateral Feishu (BL 13), Gaohuang (BL 43), and Zhongfu (LU 1) were selected; blistering cupping was administered once a day and thunder-fire moxibustion was given twice a day. One course of treatment was composed of 7 days in both groups, and 2 courses of treatment were required. Before and after treatment, the airway remodeling indexes (matrix metalloproteinase-9 [MMP-9], tissue inhibitor of matrix metalloproteinase-1 [TIMP-1], and transforming growth factor-β1 [TGF-β1]) and inflammatory indexes (interleukin [IL] -1β、IL-25) were detected by using radioimmunoassay in the patients of the two groups. The lung function, traditional Chinese medicine symptom score, and asthma quality of life questionnaire (AQLQ) score were observed in the patients of the two groups. RESULTS: After treatment, the serum levels of MMP-9, TIMP-1, TGF-β1, IL-1β, IL-25, peak expiratory flow (PEFR), traditional Chinese medicine symptom scores, and AQLQ scores were decreased compared with those before treatment in the patients of the two groups (P<0.05), and the results in the observation group were lower than those in the control group (P<0.05). After treatment, the first second forced expiratory volume (FEV1) and peak expiratory flow rate (PEF) were increased compared with those before treatment in the two groups (P<0.05), and the results in the observation group were higher than those in the control group (P<0.05). CONCLUSION On the basis of the conventional western medicine treatment, the combination of blistering cupping with thunder-fire moxibustion can effectively ameliorate the clinical symptoms of patients, reduce inflammatory levels, inhibit airway remodeling and improve the lung function and quality of life in the patients with bronchial asthma.
Humans ; Airway Remodeling ; Respiratory Sounds ; Matrix Metalloproteinase 9 ; Transforming Growth Factor beta1 ; Moxibustion ; Quality of Life ; Tissue Inhibitor of Metalloproteinase-1 ; Asthma/therapy*

OBJECTIVE: To explore whether the protein Deglycase protein 1 (DJ1) can ameliorate Alzheimer's disease (AD)-like pathology in Amyloid Precursor Protein/Presenilin 1 (APP/PS1) double transgenic mice and its possible mechanism to provide a theoretical basis for exploring the pathogenesis of AD. METHODS: Adeno-associated viral vectors (AAV) of DJ1-overexpression or DJ1-knockdown were injected into the hippocampus of 7-month-old APP/PS1 mice to construct models of overexpression or knockdown. Mice were divided into the AD model control group (MC), AAV vector control group (NC), DJ1-overexpression group (DJ1 ⁺), and DJ1-knockdown group (DJ1 ^-). After 21 days, the Morris water maze test, immunohistochemistry, immunofluorescence, and western blotting were used to evaluate the effects of DJ1 on mice. RESULTS: DJ1 ⁺ overexpression decreased the latency and increased the number of platform traversals in the water maze test. DJ1 ^- cells were cured and atrophied, and the intercellular structure was relaxed; the number of age spots and the expression of AD-related proteins were significantly increased. DJ1 ⁺ increased the protein expression of Nuclear factor erythroid 2-related factor 2 (NRF2), heme oxygenase-1 (HO-1), light chain 3 (LC3), phosphorylated AMPK (p-AMPK), and B cell lymphoma-2 (BCL-2), as well as the antioxidant levels of total superoxide dismutase (T-SOD), total antioxidant capacity (T-AOC), and Glutathione peroxidase (GSH-PX), while decreasing the levels of Kelch-like hydrates-associated protein 1 (Keap1), mammalian target of rapamycin (mTOR), p62/sequestosome1 (p62/SQSTM1), Caspase3, and malondialdehyde (MDA). CONCLUSION DJ1-overexpression can ameliorate learning, memory, and AD-like pathology in APP/PS1 mice, which may be related to the activation of the NRF2/HO-1 and AMPK/mTOR pathways by DJ1.
Animals ; Mice ; Alzheimer Disease/therapy* ; AMP-Activated Protein Kinases/metabolism* ; Amyloid beta-Protein Precursor/metabolism* ; Antioxidants/metabolism* ; Disease Models, Animal ; Hippocampus/metabolism* ; Kelch-Like ECH-Associated Protein 1/metabolism* ; Mammals/metabolism* ; Mice, Inbred C57BL ; Mice, Transgenic ; NF-E2-Related Factor 2/metabolism* ; Presenilin-1/metabolism* ; TOR Serine-Threonine Kinases/metabolism*

This study aimed to investigate the mechanism of Psoraleae Fructus in improving the learning and memory ability of APP/PS1 mice by serum metabolomics, screen the differential metabolites of Psoraleae Fructus on APP/PS1 mice, and reveal its influence on the metabolic pathway of APP/PS1 mice. Thirty 3-month-old APP/PS1 mice were randomly divided into a model group and a Psoraleae Fructus extract group, and another 15 C57BL/6 mice of the same age were assigned to the blank group. The learning and memory ability of mice was evaluated by the Morris water maze and novel object recognition tests, and metabolomics was used to analyze the metabolites in mouse serum. The results of the Morris water maze test showed that Psoraleae Fructus shortened the escape latency of APP/PS1 mice(P<0.01), and increased the number of platform crossing and residence time in the target quadrant(P<0.01). The results of the novel object recognition test showed that Psoraleae Fructus could improve the novel object recognition index of APP/PS1 mice(P<0.01). Eighteen differential metabolites in serum were screened out by metabolomics, among which the levels of arachidonic acid, tryptophan, and glycerophospholipid decreased after drug administration, while the levels of glutamyltyrosine increased after drug administration. The metabolic pathways involved included arachidonic acid metabolism, glycerophospholipid metabolism, tryptophan metabolism, linoleic acid metabolism, α-linolenic acid metabolism, and glycerolipid metabolism. Therefore, Psoraleae Fructus can improve the learning and memory ability of APP/PS1 mice, and its mechanism may be related to the effects in promoting energy metabolism, reducing oxidative damage, protecting central nervous system, reducing neuroinflammation, and reducing Aβ deposition. This study is expected to provide references for Psoraleae Fructus in the treatment of Alzheimer's disease(AD) and further explain the mechanism of Psoraleae Fructus in the treatment of AD.
Mice ; Animals ; Amyloid beta-Protein Precursor/genetics* ; Mice, Transgenic ; Arachidonic Acid ; Tryptophan ; Mice, Inbred C57BL ; Alzheimer Disease/genetics* ; Maze Learning ; Glycerophospholipids ; Disease Models, Animal ; Amyloid beta-Peptides/metabolism*

Objective To explore the effect of knocking down Rho-associated coiled-coil kinase (ROCK2) gene on the cognitive function of amyloid precursor protein/presenilin-1 (APP/PS1) double transgenic mice and its mechanism. Methods APP/PS1 double transgenic mice were randomly divided into AD model group (AD group), ROCK2 gene knock-down group (shROCK2 group), ROCK2 gene knock-down control group (shNCgroup), and wild-type C57BL/6 mice of the same age served as the wild-type control (WT group). Morris water maze and Y maze were employed to test the cognitive function of mice. Neuron morphology was detected by Nissl staining. Immunofluorescence histochemical staining was used to detect the expression of phosphorylated dynamin-related protein 1 (p-Drp1) and mitochondrial fusion 1 (Mfn1). Western blot analysis was used to detect the expression ROCK2, cleaved-caspase-3 (c-caspase-3), B-cell lymphoma 2 (Bcl2), Bcl2-related protein X (BAX), p-Drp1, mitochondrial fission 1 (Fis1), optic atrophy 1 (OPA1), Mfn1 and Mfn2. Results Compared with AD group mice, the expression of ROCK2 in shROCK2 group mice was significantly reduced; the cognitive function was significantly improved with the number of neurons in the hippocampal CA3 and DG areas increasing, and nissl bodies were deeply stained; the expression of c-caspase-3 and BAX was decreased, while the expression of Bcl2 was increased; the expression of mitochondrial division related proteins p-Drp1 and Fis1 were decreased, while the expression of mitochondrial fusion-related proteins OPA1, Mfn1 and Mfn2 were increased. Conclusion Knock-down of ROCK2 gene can significantly improve the cognitive function and inhibit the apoptosis of nerve cells of APP/PS1 mice. The mechanism may be related to promoting mitochondrial fusion and inhibiting its division.
Animals ; Mice ; Alzheimer Disease/pathology* ; Amyloid beta-Peptides/metabolism* ; Amyloid beta-Protein Precursor ; Apoptosis/genetics* ; bcl-2-Associated X Protein ; Caspase 3 ; Cognition ; Disease Models, Animal ; Mice, Inbred C57BL ; Mice, Transgenic ; Mitochondrial Dynamics/genetics*

Foreign body reactions induced by macrophages often cause delay or failure of wound healing in the application of tissue engineering scaffolds. This study explores the application of nanosilver (NAg) to reduce foreign body reactions during scaffold transplantation. An NAg hybrid collagen-chitosan scaffold (NAg-CCS) was prepared using the freeze-drying method. The NAg-CCS was implanted on the back of rats to evaluate the effects on foreign body reactions. Skin tissue samples were collected for histological and immunological evaluation at variable intervals. Miniature pigs were used to assess the effects of NAg on skin wound healing. The wounds were photographed, and tissue samples were collected for molecular biological analysis at different time points post-transplantation. NAg-CCS has a porous structure and the results showed that it could release NAg constantly for two weeks. The NAg-CCS group rarely developed a foreign body reaction, while the blank-CCS group showed granulomas or necrosis in the subcutaneous grafting experiment. Both matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were reduced significantly in the NAg-CCS group. The NAg-CCS group had higher interleukin (IL)-10 and lower IL-6 than the blank CCS group. In the wound healing study, M1 macrophage activation and inflammatory-related proteins (inducible nitric oxide synthase (iNOS), IL-6, and interferon-‍γ (IFN-‍γ)) were inhibited by NAg. In contrast, M2 macrophage activation and proinflammatory proteins (arginase-1, major histocompatibility complex-II (MHC-II), and found in inflammatory zone-1 (FIZZ-1)) were promoted, and this was responsible for suppressing the foreign body responses and accelerating wound healing. In conclusion, dermal scaffolds containing NAg suppressed the foreign body reaction by regulating macrophages and the expression of inflammatory cytokines, thereby promoting wound healing.
Animals ; Rats ; Swine ; Interleukin-6 ; Macrophage Activation ; Tissue Inhibitor of Metalloproteinase-1 ; Wound Healing ; Foreign-Body Reaction ; Foreign Bodies ; Chitosan

Mutations in genes encoding amyloid precursor protein (APP) and presenilins (PSs) cause familial forms of Alzheimer's disease (AD), a neurodegenerative disorder strongly associated with aging. It is currently unknown whether and how AD risks affect early brain development, and to what extent subtle synaptic pathology may occur prior to overt hallmark AD pathology. Transgenic mutant APP/PS1 over-expression mouse lines are key tools for studying the molecular mechanisms of AD pathogenesis. Among these lines, the 5XFAD mice rapidly develop key features of AD pathology and have proven utility in studying amyloid plaque formation and amyloid β (Aβ)-induced neurodegeneration. We reasoned that transgenic mutant APP/PS1 over-expression in 5XFAD mice may lead to neurodevelopmental defects in early cortical neurons, and performed detailed synaptic physiological characterization of layer 5 (L5) neurons from the prefrontal cortex (PFC) of 5XFAD and wild-type littermate controls. L5 PFC neurons from 5XFAD mice show early APP/Aβ immunolabeling. Whole-cell patch-clamp recording at an early post-weaning age (P22-30) revealed functional impairments; although 5XFAD PFC-L5 neurons exhibited similar membrane properties, they were intrinsically less excitable. In addition, these neurons received smaller amplitude and frequency of miniature excitatory synaptic inputs. These functional disturbances were further corroborated by decreased dendritic spine density and spine head volumes that indicated impaired synapse maturation. Slice biotinylation followed by Western blot analysis of PFC-L5 tissue revealed that 5XFAD mice showed reduced synaptic AMPA receptor subunit GluA1 and decreased synaptic NMDA receptor subunit GluN2A. Consistent with this, patch-clamp recording of the evoked L23>L5 synaptic responses revealed a reduced AMPA/NMDA receptor current ratio, and an increased level of AMPAR-lacking silent synapses. These results suggest that transgenic mutant forms of APP/PS1 overexpression in 5XFAD mice leads to early developmental defects of cortical circuits, which could contribute to the age-dependent synaptic pathology and neurodegeneration later in life.
Mice ; Animals ; Alzheimer Disease/pathology* ; Amyloid beta-Peptides/metabolism* ; Receptors, N-Methyl-D-Aspartate/metabolism* ; Amyloid beta-Protein Precursor/metabolism* ; Mice, Transgenic ; Neurons/metabolism* ; Receptors, AMPA/metabolism* ; Disease Models, Animal