miR-495-3p depresses cell proliferation and migration by downregulating HMGB1 in colorectal cancer.

BACKGROUND: MicroRNAs play an important role in the genesis and progression of tumours, including colorectal cancer (CRC), which has a high morbidity and mortality rate. In this research, the role of miR-495-3p and HMGB1 in CRC was investigated. METHODS: We performed qRT-PCR to detect the expression of miR-495-3p in colorectal cancer tissues and cell lines. Functional experiments, such as CCK-8, EdU, Transwell and apoptosis assays, were conducted to explore the effects of miR-495-3p on the proliferation, migration and apoptosis of CRC cells in vitro. Then, database prediction, dual-luciferase reporter gene assays and functional experiments verified the role of the miR-495-3p target gene HMGB1 in CRC. Finally, rescue experiments were performed to investigate whether overexpression of HMGB1 could reverse the inhibitory effect of miR-495-3p on CRC cell proliferation in vivo and in vitro. RESULTS: miR-495-3p was downregulated in colorectal cancer tissues and cell lines, inhibited the proliferation and migration of colorectal cancer cells and promoted cell apoptosis. Database prediction and dual-luciferase reporter gene assays showed that HMGB1 was the downstream target gene of miR-495-3p. We finally demonstrated that miR-495-3p inhibited CRC cell proliferation by targeting HMGB1 in vitro and in vivo. CONCLUSION: Our research shows that miR-495-3p inhibits the progression of colorectal cancer by downregulating the expression of HMGB1, which indicates that miR-495-3p may become a potential therapeutic target for colorectal cancer.

Comparative diagnostic accuracy of ACE-III and MoCA for detecting mild cognitive impairment.

OBJECTIVE: The aim of this study was to validate the reliability of the Chinese version of Addenbrooke's Cognitive Examination III (ACE-III) for detecting mild cognitive impairment. Furthermore, the present study compares the diagnostic accuracy of ACE-III with that of Montreal Cognitive Assessment (MoCA). METHODS: One hundred and twenty patients with MCI and 136 healthy controls were included in the study. All patients were evaluated by the Chinese version of ACE-III, MoCA and MMSE. RESULTS: Subjects in the control group showed better performance in ACE-III total score and its subdomain scores than those in the MCI group. There was a significantly positive correlation between ACE-III total score and MoCA score. Meanwhile, there was also a significantly positive correlation between ACE-III total score and MMSE score. For ACE-III total score, a cut-off point of 85 yielded a sensitivity of 97.3% and a specificity of 90.7%. The AUC for ACE-III total score was 0.978. For MoCA, a cut-off point of 23 yielded a sensitivity of 86.5% and a specificity of 97.7%. The AUC for MoCA was 0.961. There were no significant differences in diagnostic accuracy between ACE-III and MoCA. CONCLUSION: The present findings support that both ACE-III and MoCA are useful for detecting MCI in early stages.

Hydrogen sulfide inhibits the renal fibrosis of obstructive nephropathy.

Hydrogen sulfide has recently been found decreased in chronic kidney disease. Here we determined the effect and underlying mechanisms of hydrogen sulfide on a rat model of unilateral ureteral obstruction. Compared with normal rats, obstructive injury decreased the plasma hydrogen sulfide level. Cystathionine-ß-synthase, a hydrogen sulfide-producing enzyme, was dramatically reduced in the ureteral obstructed kidney, but another enzyme cystathionine-γ-lyase was increased. A hydrogen sulfide donor (sodium hydrogen sulfide) inhibited renal fibrosis by attenuating the production of collagen, extracellular matrix, and the expression of α-smooth muscle actin. Meanwhile, the infiltration of macrophages and the expression of inflammatory cytokines including interleukin-1ß, tumor necrosis factor-α, and monocyte chemoattractant protein-1 in the kidney were also decreased. In cultured kidney fibroblasts, a hydrogen sulfide donor inhibited the cell proliferation by reducing DNA synthesis and downregulating the expressions of proliferation-related proteins including proliferating cell nuclear antigen and c-Myc. Further, the hydrogen sulfide donor blocked the differentiation of quiescent renal fibroblasts to myofibroblasts by inhibiting the transforming growth factor-ß1-Smad and mitogen-activated protein kinase signaling pathways. Thus, low doses of hydrogen sulfide or its releasing compounds may have therapeutic potentials in treating chronic kidney disease.

Autophagic impairment contributes to systemic inflammation-induced dopaminergic neuron loss in the midbrain.

BACKGROUND: Neuroinflammation plays an important role in the pathogenesis of Parkinson's disease (PD), inducing and accelerating dopaminergic (DA) neuron loss. Autophagy, a critical mechanism for clearing misfolded or aggregated proteins such as α-synuclein (α-SYN), may affect DA neuron survival in the midbrain. However, whether autophagy contributes to neuroinflammation-induced toxicity in DA neurons remains unknown. RESULTS: Intraperitoneal injection of lipopolysaccharide (LPS, 5 mg/kg) into young (3-month-old) and aged (16-month-old) male C57BL/6J mice was observed to cause persistent neuroinflammation that was associated with a delayed and progressive loss of DA neurons and accumulation of α-SYN in the midbrain. The autophagic substrate-p62 (SQSTM1) persistently increased, whereas LC3-II and HDAC6 exhibited early increases followed by a decline. In vitro studies further demonstrated that TNF-α induced cell death in PC12 cells. Moreover, a sublethal dose of TNF-α (50 ng/ml) increased the expression of LC3-II, p62, and α-SYN, implying that TNF-α triggered autophagic impairment in cells. CONCLUSION: Neuroinflammation may cause autophagic impairment, which could in turn result in DA neuron degeneration in midbrain.

Crosstalk between the proteasome system and autophagy in the clearance of α-synuclein.

AIM: A growing body of evidence suggests that α-synuclein accumulation may play an important role in the pathogenesis of Parkinson's disease. The aim of this study was to investigate the roles of the proteasome and autophagy pathways in the clearance of wild-type and mutant α-synuclein in PC12 cells. METHODS: PC12 cells overexpressing either wild-type or A30P mutant α-synuclein were treated with the proteasome inhibitor epoxomicin, the macroautophagy inhibitor 3-MA and the macroautophagy activator rapamycin alone or in combination. The cell viability was assessed using MTT assay. Immunofluorescence and Western blot analysis were used to detect the level of α-synuclein, LAMP-2A, E1 activase, and E2 ligase in the cells. Chymotrypsin-like proteasomal activity was measured using a commercial kit. RESULTS: When the proteasome and macroautophagy in the wild-type and mutant cells were inhibited with epoxomicin and 3-MA, respectively, the cell viability was significantly decreased, and the α-synuclein level was increased. Both epoxomicin and 3-MA activated the chaperone-mediated autophagy (CMA) by increasing the level of the CMA-limiting enzyme LAMP-2A. Furthermore, 3-MA or epoxomicin significantly decreased chymotrypsin-like proteasomal activity. 3-MA or epoxomicin did not change E1 activase expression in either mutant or wild-type cells, but increased E2 ligase expression, especially when used together. Macroautophagy inducer rapamycin increased the cell viability and reduced epoxomicin-induced α-synuclein accumulation. Interestingly, CMA was also activated by rapamycin. CONCLUSION: Our results demonstrate the existence of complex crosstalk between different forms of autophagy and between autophagy and the proteasome pathway in the clearance of α-synuclein in PC12 cells.

Application and interpretation of current autophagy inhibitors and activators.

Autophagy is the major intracellular degradation system, by which cytoplasmic materials are delivered to and degraded in the lysosome. As a quality control mechanism for cytoplasmic proteins and organelles, autophagy plays important roles in a variety of human diseases, including neurodegenerative diseases, cancer, cardiovascular disease, diabetes and infectious and inflammatory diseases. The discovery of ATG genes and the dissection of the signaling pathways involved in regulating autophagy have greatly enriched our knowledge on the occurrence and development of this lysosomal degradation pathway. In addition to its role in degradation, autophagy may also promote a type of programmed cell death that is different from apoptosis, termed type II programmed cell death. Owing to the dual roles of autophagy in cell death and the specificity of diseases, the exact mechanisms of autophagy in various diseases require more investigation. The application of autophagy inhibitors and activators will help us understand the regulation of autophagy in human diseases, and provide insight into the use of autophagy-targeted drugs. In this review, we summarize the latest research on autophagy inhibitors and activators and discuss the possibility of their application in human disease therapy.

dl-3-n-Butylphthalide prevents oxidative damage and reduces mitochondrial dysfunction in an MPP(+)-induced cellular model of Parkinson's disease.

The aim of the present study was to explore the neuroprotective effects and mechanisms of action of dl-3-n-butylphthalide (NBP) in a 1-methyl-4-phenylpyridiniumion (MPP(+))-induced cellular model of Parkinson's disease (PD). NBP was extracted from seeds of Apium graveolens Linn. (Chinese celery). MPP(+) treatment of PC12 cells caused reduced viability, formation of reactive oxygen, and disruption of mitochondrial membrane potential. Our results indicated that NBP reduced the cytotoxicity of MPP(+) by suppressing the mitochondrial permeability transition, reducing oxidative stress, and increasing the cellular GSH content. NBP also reduced the accumulation of alpha-synuclein, the main component of Lewy bodies. Given that NBP is safe and currently used in clinical trials for stroke patients, NBP will likely be a promising chemical for the treatment of PD.

[PCR-based STR genotyping of sweat latent fingerprint samples involved in cases].

OBJECTIVE: To study the extracting and genotyping method of sweat latent fingerprint samples involved in cases. METHOD: Chlex 100 extraction method was used to extract DNA. STR loci were typed after PCR amplification by Profiler Plus kit. RESULTS: All the sweat latent fingerprint samples involved in cases obtained reliable results of STR genotyping. CONCLUSION: It is very important to find and extract sweat latent fingerprint samples properly for STR genotyping.