Autophagic-Related anticancer effect of grapes extract and tomatoes extract: Ex-Vivo study

Cells undergo autophagy to save themselves from injury, but progressive autophagy can cause cell death. This study characterized and compared the effect of grape (resveratrol) and tomato (lycopene) extracts and their combination on modulating autophagy-related miRNA and its target gene in squamous cell carcinoma cell line. Docking analysis for extracts and selected genes was performed. Methyl Thiazol Tetrazolium assays were used to assess the cytotoxicity of extracts and their combination toward HEp-2 cells. qRT-PCR was used to quantify changes in gene expression. Data were statistically analyzed. miRNA-20a was identified as a potential effector in laryngeal cancer, and sequestosome-1 (SQSTM1) was its target gene. Docking analysis showed that resveratrol interacted with miRNA-20a and showed less affinity toward SQSTM1. Hydrogen bonds and hydrophobic interactions were predicted. In contrast, lycopene showed less affinity toward miRNA-20a than resveratrol. Increasing doses of resveratrol, lycopene, and their combination induced a statistically significant reduction in mean percent viability and mean fold changes of miRNA-20a and SQSTM1 expression in treated HEp-2 cells. Pearson's correlation showed a statistically significant positive correlation between miRNA-20a and SQSTM1 (R=0.812, p≤0.001). Grape and tomato extracts and their combination display promising cytotoxicity against HEp-2 cells in a dose- and time-dependent fashion. Both extracts reduce the expression of miRNA-20a and SQSTM1 with subsequent inhibition autophagy and promotion of apoptosis in HEp-2 cells.

Las células se someten a autofagia para salvarse de lesiones, pero la autofagia progresiva puede provocar la muerte celular. Este estudio caracterizó y comparó el efecto de los extractos de uva (resveratrol) y tomate (licopeno) y su combinación en la modulación de miARN relacionado con la autofagia y su gen diana en la línea celular de carcinoma de células escamosas. Se realizó análisis de acoplamiento para extractos y genes seleccionados. Se utilizaron ensayos de metil tiazol tetrazolio para evaluar la citotoxicidad de los extractos y su combinación frente a las células HEp-2. qRT-PCR se utilizó para cuantificar los cambios en la expresión génica. Los datos fueron analizados estadísticamente. El miARN-20a se identificó como un efector potencial en el cáncer de laringe y el secuenciasoma-1 (SQSTM1) fue su gen diana. El análisis de acoplamiento mostró que el resveratrol interactuaba con miRNA-20a y mostraba menos afinidad hacia SQSTM1. Se predijeron enlaces de hidrógeno e interacciones hidrofóbicas. Por el contrario, el licopeno mostró menos afinidad hacia el miARN-20a que el resveratrol. El aumento de las dosis de resveratrol, licopeno y su combinación indujo una reducción estadísticamente significativa en el porcentaje medio de viabilidad y los cambios medios en la expresión de miRNA- 20a y SQSTM1 en las células HEp-2 tratadas. La correlación de Pearson mostró una correlación positiva estadísticamente significativa entre miRNA-20a y SQSTM1 (R=0,812, p≤0,001). Los extractos de uva y tomate y su combinación muestran una citotoxicidad prometedora contra las células HEp-2 de forma dependiente de la dosis y el tiempo. Ambos extractos reducen la expresión de miRNA-20a y SQSTM1 con la posterior inhibición de la autofagia y promoción de la apoptosis en células HEp-2.

Advances in molecular function of p62 protein and its role in diseases / 生物工程学报

Sequestosome 1 (SQSTM1/p62) is a selective autophagy adaptor protein that plays an important role in the clearance of proteins to be degraded as well as in the maintenance of cellular proteostasis. p62 protein has multiple functional domains, which interact with several downstream proteins to precisely regulate multiple signaling pathways, thereby linking p62 to oxidative defense systems, inflammatory responses and nutrient sensing. Studies have shown that mutation or abnormal expression of p62 is closely related to the occurrence and development of various diseases, including neurodegenerative diseases, tumors, infectious diseases, genetic diseases and chronic diseases. This review summarizes the structural features and molecular functions of p62. Moreover, we systematically introduce its multiple functions in protein homeostasis and regulation of signaling pathways. Furthermore, the complexity and versatility of p62 in the occurrence and development of diseases are summarized, with the aim to provide a reference for understanding the function of p62 protein and facilitating related disease research.

Anthelmintics nitazoxanide protects against experimental hyperlipidemia and hepatic steatosis in hamsters and mice

Lipid metabolism disorders contribute to hyperlipidemia and hepatic steatosis. It is ideal to develop drugs simultaneous improving both hyperlipidemia and hepatic steatosis. Nitazoxanide is an FDA-approved oral antiprotozoal drug with excellent pharmacokinetic and safety profile. We found that nitazoxanide and its metabolite tizoxanide induced mild mitochondrial uncoupling and subsequently activated AMPK in HepG2 cells. Gavage administration of nitazoxanide inhibited high-fat diet (HFD)-induced increases of liver weight, blood and liver lipids, and ameliorated HFD-induced renal lipid accumulation in hamsters. Nitazoxanide significantly improved HFD-induced histopathologic changes of hamster livers. In the hamsters with pre-existing hyperlipidemia and hepatic steatosis, nitazoxanide also showed therapeutic effect. Gavage administration of nitazoxanide improved HFD-induced hepatic steatosis in C57BL/6J mice and western diet (WD)-induced hepatic steatosis in Apoe -/- mice. The present study suggests that repurposing nitazoxanide as a drug for hyperlipidemia and hepatic steatosis treatment is promising.

High expression of LC3A, LC3B, and p62/SQSTM1 autophagic proteins in human colonic ganglion cells

@#Introduction: Autophagy is a mechanism that degrades large damaged organelles and misfolded proteins to maintain the homeostasis in all cells. It plays double-faceted roles in tumourigenesis and prevention of various cancers. In our side observation of investigating the prognostic value of autophagy in colorectal cancer (CRC), we found high expression of autophagy proteins (LC3A, LC3B, and p62/SQSTM1) in the colonic ganglion cells. To our best understanding, this is the first paper reporting such finding. Materials and Methods: Formalin-fixed paraffin-embedded (FFPE) CRC tissues blocks were retrieved and confirmed by haematoxylin & eosin (H&E) staining. Immunohistochemistry (IHC) targeting autophagy proteins (LC3A, LC3B, and p62/SQSTM1) was then performed followed by pathological examination. Results: All three autophagy proteins were present in both normal and tumour tissues of CRC patients. Interestingly, high expression of autophagy proteins in colonic ganglion cells was consistently seen regardless of tissue type (normal or cancer) or tumour site (caecum, ascending, transverse, descending, sigmoid colon and rectum). Conclusions: This work highlights the high autophagic activities in human colonic ganglion cells.

Moxibustion improves cardiac function by up-regulating autophagy-related proteins of cardiomyocytes in rats with chronic heart failure / 针刺研究

OBJECTIVE: To observe the effect of moxibustion on cardiac function and the expression of autophagy-related proteins microtubule-associated protein 1 light chain 3 (LC3) and selective autophagy receptor signaling adaptor sequestosome 1 (SQSTM1/p62) in rats with chronic heart failure (CHF), so as to explore its underlying mechanisms in preventing and treating CHF. METHODS: Sixty male SD rats were randomly divided into normal, model, moxibustion, autophagy inhibitor 3-methyladenine (3-MA) and autophagy agonist rapamycin (RAPA) groups (n＝12 rats/group). The CHF model was established by intrape-ritoneal injection of adriamycin (ADR, 2 mg/kg, once every week for 12 weeks). Mild moxibustion was applied to bilateral "Feishu" (BL13) and "Xinshu" (BL15) for 20 min every time. Rats of the 3-MA group were treated by intraperitoneal injection of 3-MA suspension (15 mg/kg), and those of the RAPA group treated by gavage of RAPA suspension (2 mg/kg). All the treatments were given once a day for 3 weeks. The heart rate (HR), cardiac output (CO), left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP) and maximum rising and lowering rates of left ventricular pressure (±dp/dtmax) were measured for assessing the cardiac performance. Histopathological changes of the left ventricular myocardium were observed by HE staining. The expression levels of LC3-Ⅰ， LC3-Ⅱ and p62 proteins of the left ventricle myocardium tissue were detected by Western blot. RESULTS: After modeling, the pathological changes of myocardium (as myocardial cell swelling with vacuoles, myocardial fibre breakage, etc.) were obvious, and the HR, LVEDP, LC3-Ⅱ and LC3-Ⅱ/Ⅰ protein expression levels were significantly increased in the model group compared with the normal group (P<0.01), while the CO, LVSP, ±dp/dtmax, and the expression of p62 protein were significantly down-regulated (P<0.01). Following the interventions, the myocardial injury was reduced, the HR, LVEDP, LC3-Ⅱ and LC3-Ⅱ/Ⅰ levels in both moxibustion and 3-MA groups were significantly decreased (P<0.05, P<0.01), while the CO, LVSP, ±dp/dtmax and p62 expression level were significantly increased relevant to the model group (P<0.05, P<0.01). In addition, the ratio of LC3-Ⅱ/Ⅰ was significantly increased, and the expression level of p62 significantly down-regulated in the RAPA group compared with the model group (P<0.01). CONCLUSION: Moxibustion can improve cardiac function in CHF rats, which may be related to its effects in down-regulating the ratio of LC3-Ⅱ/Ⅰ and up-regulating the expression of p62 protein to inhibit cardiomyocyte autophagy.

Changes of autophagy-related genes in the brains of the rats in the developmental stage with epilepsy / 中华实用儿科临床杂志

Objective To explore the changes of Beclin-1,P62/SQSTM1,microtubule-associated protein 1 light chain 3 (LC3)and unc-51 like autophagy activating kinase 1 (ULK-1)in the brains of the rats in the deve-lopmental stage with epilepsy. Methods Seventy-two male Sprague Dawley (SD)rats aged 21 days were randomly divided into the control group and the epilepsy group. The rats in 2 groups were randomly subdivided into 4 groups according to the time intervals (3 h,6 h,12 h and 48 h),respectively,with 9 rats in each group. The rats in the epilep-sy group were injected with kainic acid (12 mg/kg)to induce epilepsy,and the rats in the control group were injected with equal volume of saline. The rats in 2 groups were anaesthetized and sacrificed. Then,the brain tissues of the rats were quickly removed according to the time intervals. The brain damages were determined by adopting Nissl staining method. The apoptotic cells were detected by Terminal - deoxynucleoitidyl transferase mediated nick end labeling (TUNEL)assays. The expressions of Beclin-1,P62/SQSTM1,LC3 and ULK-1 mRNA levels in cortex were mea-sured by using real-time quantitative polymerase chain reaction (qPCR)analysis. Results Nissl staining indicated that many neurons were damaged performing vague outline,irregularly aligned,pyknotic nuclei and shrunken somata in the epilepsy 48 h group. In addition,there was a huge loss of neurons in cortex in the epilepsy 48 h group [(82 ± 8)num-bers],compared with the control group [(122 ± 8)numbers],and the difference was statistically significant (F＝3. 768, P＝0. 01). The apoptotic cells tremendously increased in the epilepsy 48 h group [(13 ± 7)numbers],compared with the control group [(2 ± 1)numbers]by TUNEL analysis,and the diffe-rence was statistically significant (t＝ -3. 821, P＝0. 003). qPCR showed the mRNA levels of Beclin-1,P62/SQSTM1,LC3 and ULK-1 were upregulated in the epi-lepsy 12 h group (1. 70 ± 0. 75,1. 75 ± 0. 77,1. 52 ± 0. 43,7. 48 ± 6. 12)and the epilepsy 48 h group (1. 63 ± 0. 43, 1. 48 ± 0. 74,1. 74 ± 0. 55,7. 69 ± 5. 65),compared with the control group (1. 00,1. 00,1. 00,1. 00),and the differences were statistically significant (F＝2. 820,3. 452,5. 811,5. 002,all P＜0. 05). Conclusion The autophagy activates be-fore apoptosis occurs,and autophagy-related genes probably are involved in epilepsy-induced brain damage.

To screen for SQSTM1/p62 gene in Chinese patients with familial amyotrophic lateral sclerosis carrying superoxide dismutase 1 mutation / 中华内科杂志

Objective To explore the clinical features and SQSTM1/p62 gene mutations in Chinese Han patients with familial amyotrophic lateral sclerosis linked superoxide dismutase 1 (SOD1) mutation (FALS-SOD1).Methods A total of 13 FALS-SOD1 probands and 100 healthy controls were studied,with DNA extracted from the peripheral blood.Sequencing was carried out at 8 exons,intron-exon boundaries and promoter region (2-kb upstream from the coding sequence) of SQSM1/p62.Clinical data were collected and all patients were followed-up.Phenotype-genotype relationship was analyzed.Results The insertion of T was found in intron 5 of SQSTM1/p62 gene [+ 1 insert T (TT ＞ TG)] in a FALS-SOD1 G16A male proband,with limbs as the symptom onset and faster disease progression than the other two SOD1 G16A probands without SQSTM1/p62 gene mutation.Conclusions The insertion of T in the intron 5 of SQSTM1/ p62 gene may promote the ALS progression by damaging p62 function in the FALS-SOD1 G16A proband.