Effect of Guipitang on ERK1/2 and p38 MAPK in Rats with Myocardial Ischemia / 中国实验方剂学杂志

ObjectiveTo explore the therapeutic effect and mechanism of Guipitang on rats with myocardial ischemia. MethodFifty SD rats were divided into five groups： a control group， a model group， low and high-dose Guipitang （7.52， 15.04 g·kg-1） groups， and a trimetazidine group （0.002 g·kg-1）. By intragastric administration of vitamin D3 and feeding rats with high-fat forage and injecting isoproterenol， the rat model of myocardial ischemia was established. After drug treatment of 15 d， an electrocardiogram （ECG） was performed to analyze the degree of myocardial injury. A fully automatic biochemical analyzer was used to detect the changes in the serum levels of total cholesterol （TC）， high-density lipoprotein cholesterol （HDL-C）， triglyceride （TG）， and low-density lipoprotein cholesterol （LDL-C）. Hematoxylin-eosin （HE） staining and Masson staining were used to observe myocardial histopathological changes. TdT-mediated dUTP nick end labeling （TUNEL） staining was used to detect cardiomyocyte apoptosis. Western blot was adopted to detect the protein levels of extracellular signal-regulated kinase 1/2 （ERK1/2）， phospho-ERK1/2 （p-ERK1/2）， p38 mitogen-activated protein kinase （p38 MAPK）， phospho-p38 MAPK （p-p38 MAPK）， B-cell lymphoma-2 （Bcl-2）-associated X （Bax）， Bcl-2， and cleaved cysteine aspartate proteolytic enzyme （cleaved Caspase-3）. ResultCompared with the control group， the ECG S-T segment decreased in the model group. The serum levels of TC， TG， and LDL-C were increased significantly （P<0.05）. The arrangement of myocardial tissue was disordered， and the proportion of cardiomyocyte apoptosis increased. The protein levels of cleaved Caspase-3， Bax， and p-p38 MAPK in the heart were increased， and the Bcl-2 expression was decreased （P<0.05）. Compared with the model group， the S-T segment downward shift was restored in the low and high-dose Guipitang groups and trimetazidine group， and the levels of TC， TG， and LDL-C were decreased. The protein expression of cleaved Caspase-3 and Bax in the heart dropped， and p-p38 MAPK and p-ERK1/2 protein expressions increased significantly （P<0.05）. The degree of myocardial injury was alleviated， and the proportion of cardiomyocyte apoptosis decreased. Bcl-2 protein expression was increased significantly in the low-dose Guipitang group （P<0.05）. ERK1/2 and p38 MAPK proteins had no significant difference among different groups. ConclusionGuipitang could alleviate myocardial injury and inhibit cardiomyocyte apoptosis in rats by activating the expression of ERK1/2 and p38 MAPK.

The diagnostic value of KRAS gene mutation in appendiceal adenocarcinoma / 中国医师杂志

Objective:To analyze the mutation characteristics of Kirsten rat sarcoma virus oncogene homology (KRAS) gene in patients with appendiceal adenocarcinoma and its relationship with the activity of Ras Raf Mitogen activated protein kinase/extracellular regulated protein kinase (MAPK/ERK) signaling pathway.Methods:A total of 41 patients with appendiceal adenocarcinoma who were treated in the Lishui Central Hospital from January 2014 to January 2020 were selected as the observation group, and 50 patients with Appendicitis who were operated at the same time were randomly selected as the control group. Clinical and follow-up data were collected, and the mutation of the KRAS gene in the patient′s tissue was measured using the snapshot method. The expression of key proteins in the MAPK/ERK signaling pathway in cancer tissue was measured using Western blotting (WB) assay. We compared the clinical characteristics and prognosis of patients with KRAS mutation and non KRAS mutation appendiceal adenocarcinoma.Results:The KRAS gene mutation rate in the observation group was higher than that in the control group (41.5% vs 10.0%), and the expression levels of p-ARAF/ARAF, p-MEK1/MEK1, and p-ERK1/ERK1 proteins were also higher than those in the control group. The differences between the groups were statistically significant (all P<0.05). The protein expression levels of p-ARAF/ARAF, p-MEK1/MEK1, p-ERK1/ERK1 in KRAS mutation patients in the observation group were significantly higher than those in non KRAS mutation patients. The proportion of stage IV, positive rates of carcinoembryonic antigen (CEA), carbohydrate antigen (CA)199 and CA125 in KRAS mutation patients were higher than those in non KRAS mutation patients, and the survival time and progression free survival time were shorter than those in non KRAS mutation patients, with statistical significance (all P<0.05). Conclusions:The mutation rate of KRAS in appendix adenocarcinoma is high, and the activation of MAPK/ERK signaling pathway caused by KRAS mutation may play a role in the pathogenesis of appendix adenocarcinoma, which has the value of in-depth research.

Mechanisms and research progress of targeted therapies on regulation of autophagy by natural compounds from traditional Chinese medicine / 药学学报

Autophagy is an important physiological process that can degrade cell components and maintain cell homeostasis, divided into three types including macroautophagy, microautophagy and chaperon-mediated autophagy generally, and macroautophagy is the most common form. Autophagy can affect the progression of a variety of diseases, such as cancer, neurodegenerative diseases, heart-related diseases, and autoimmune diseases, etc. However, autophagy can promote or inhibit diseases in different circumstances because of the dual roles of autophagy. Therefore, targeted regulating autophagy may be a potential treatment plan for diseases in specific stages of disease development. Now, with the development of traditional Chinese medicine (TCM) resources and the deepening of researches on the modern utilization of TCM, many active compounds from TCM have been discovered that can target autophagy to exert pharmacological activity. Most of the natural compounds activate or inhibit autophagy by affecting the classical PI3K/AKT/mTOR autophagy pathway. In addition, some compounds can also affect autophagy through MAPKs signaling pathways such as MEK/ERK, JNK and p38MAPK. These active compounds exert various biological activities by regulating autophagy, including anti-tumor, inhibiting neurodegenerative diseases, protecting cardiomyocytes, and relief of inflammatory response. In this review, we summarized the active compounds in TCM that affect autophagy by targeting different signaling pathways and their mechanisms of regulating autophagy, also introduced the effects of active compounds on diseases after affecting autophagy. Finally, this paper summarized and prospected the development of targeted autophagy for the treatment of diseases by TCM compounds, hoping to provide clues for subsequent exploration and research.

Effect of metformin preconditioning on AMPK/PINK1 signaling pathway during myocardial ischemia-reperfusion injury in diabetic rats / 中华麻醉学杂志

Objective:To evaluate the effect of metformin preconditioning on adenosine monophosphate-activated protein kinase(AMPK)/PTEN-induced putative protein kinase(PINK1) signaling pathway during ischemia-reperfusion (I/R) injury in diabetic rats.Methods:Thirty-six clean-grade healthy male Sprague-Dawley rats, aged 6 weeks, weighing 120-160 g, were divided into 3 groups ( n=12 each) by the random number table method: diabetic sham operation group (DS group), diabetic myocardial I/R group (DI/R group) and diabetic myocardial I/R+ metformin preconditioning group(DI/R+ Met group). After 4 weeks of feeding a high-fat and high-glucose diet, the model of type 2 diabetes mellitus was induced by a single intraperitoneal injection of 1% streptozotocin 40 mg/kg. The myocardial I/R injury was induced by blocking the anterior descending branch of the left coronary artery for 30 min followed by 120-min reperfusion in anesthetized animals. In DI/R+ Met group, metformin 200 mg/kg was given by intragastric gavage once a day within 1 week before myocardial ischemia. Blood samples from the femoral vein were collected at 120 min of reperfusion for determination of the serum creatine kinase isoenzymes (CK-MB) and cardiac troponin I (cTnI) concentrations by enzyme-linked immunosorbent assay. Then the rats were sacrificed and myocardial tissues were obtained for examination of the pathological changes(by HE staining) and for determination of the percentage of myocardial infarct size (by the double staining of Ewan blue and TTC) and expression of myocardial autophagy-related protein Beclin-1, PTEN-induced putative kinase 1 (PINK1), phosphorylated 5′-adenosine monophosphate-activating protein kinase (p-AMPK), and ratio of microtubule-associated protein 1 light chain 3Ⅱ/Ⅰ (LC3Ⅱ/Ⅰ) (by Western blot). Results:Compared with DS group, the percentage of myocardial infarct size and serum CK-MB and cTnI concentrations were significantly increased, the expression of Beclin-1, p-AMPK and PINK1 in myocardial tissues was up-regulated, the ratio of LC3II/I was increased( P<0.05), and the pathological changes were aggravated in DI/R group and DI/R+ Met group. Compared with DI/R group, the percentage of myocardial infarct size and serum CK-MB and cTnI concentrations were significantly decreased, the expression of Beclin-1, p-AMPK and PINK1 in myocardial tissues was up-regulated, the ratio of LC3Ⅱ/Ⅰ was increased ( P<0.05), and the pathological changes were significantly reduced in DI/R+ Met group. Conclusions:The mechanism by which metformin preconditioning reduces myocardial I/R injury is related to activation of AMPK/PINK1 signaling pathway and up-regulation of mitochondrial autophagy in diabetic rats.

Effect of high concentration hydrogen on myocardial injury and expression of Mst1 in septic mice / 中华麻醉学杂志

Objective:To evaluate the effect of high concentration hydrogen on myocardial injury and expression of mammalian STE20-like protein kinases 1 (Mst1) in septic mice.Methods:One hundred and five clean-grade healthy male C57BL/6J mice, aged 6-8 weeks, weighing 20-25 g, were divided into 3 groups ( n=35 each) using a random number table method: sham operation group (group Sham), sepsis group (group SEP), and sepsis+ high concentration hydrogen group (group SEP+ HCH). The model of sepsis-induced myocardial injury was developed by cecal ligation and perforation in anesthetized mice. In SEP+ HCH group, high concentration hydrogen (66.7%) was inhaled for 1 h starting from 1 and 6 h after the successful preparation of the model. Twenty mice were taken from each group to observe the survival rate at day 7 after operation. Blood samples from the medial canthus were collected after deep anesthesia at 24 h after surgery for determination of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) concentrations (by enzyme-linked immunosorbent assay). Then the animals were sacrificed, and the heart tissues were taken for examination of the pathological results (with a light microscope) which were scored and for determination of apoptosis in myocardial cells (by TUNEL) and expression of Mst1, dynamic-related protein 1 (Drp1) and mitofusin 2 (Mfn2) in myocardium (by Western blot). Results:Compared with group Sham, the survival rate at 7 days after operation, pathological score, apoptosis index and concentrations of TNF-α and IL-6 were significantly increased, Mst1 and Drp1 expression was up-regulated, and Mfn2 expression was down-regulated in group SEP ( P<0.05). Compared with group SEP, the survival rate at 7 days after operation, pathological score, apoptosis index and concentrations of TNF-α and IL-6 were significantly decreased, Mst1 and Drp1 expression was down-regulated, and Mfn2 expression was up-regulated in group SEP+ HCH ( P<0.05). Conclusions:Inhalation of high-concentration hydrogen can attenuate the myocardial injury in septic mice, and the mechanism may be related to down-regulation of Mst1 expression, improvement in mitochondrial dynamics, and inhibition of apoptosis in myocardial cells.

Role of P2X4R in maintenance of trigeminal neuralgia in rats: relationship with p38 MAPK/BDNF signaling pathway / 中华麻醉学杂志

Objective:To evaluate the role of P2X4 receptor (P2X4R) in the maintenance of trigeminal neuralgia and the relationship with p38 mitogen-activated protein kinase (p38 MAPK)/brain-derived neurotrophic factor (BDNF) signaling pathway in rats.Methods:Forty-eight clean-grade healthy adult male Sprague-Dawley rats, weighing 190-230 g, aged 2-3 months, were divided into 4 groups ( n=12 each) using a random number table method: sham operation group (S group), trigeminal neuralgia group (TN group), trigeminal neuralgia+ dimethylsulfoxide (DMSO) group (TN+ DMSO group), and trigeminal neuralgia+ P2X4R specific antagonist 5-BDBD group (TN+ 5-BDBD group). The model was developed by chronic constriction of the infraorbital nerve. The infraorbital nerve was only exposed without ligation in group S. At 3, 7, 10 and 14 days after developing the model, 5 μg/μl 5-BDBD 10 μl was intrathecally injected in TN+ 5-BDBD group, and 2% DMSO 10 μl was intrathecally injected in TN+ DMSO group. The facial mechanical pain withdrawal threshold (MWT) was measured at 1 day before developing the model and 1, 3, 7, 10, 14 and 28 days after developing the model (T 0-6). The rats were sacrificed and the trigeminal ganglia were taken for determination of the expression of P2X4R, p38 MAPK, phosphorylated p38 MAPK (p-p38 MAPK) and BDNF (by Western blot) and contents of tumor necrosis factor (TNF)-α and interleukin (IL)-1β and IL-6 (by enzyme-linked immunosorbent assay). Results:Compared with group S, the MWT was significantly decreased at T 1-6, the expression of P2X4R, p-p38 MAPK and BDNF in trigeminal ganglion was up-regulated, and the contents of TNF-α, IL-1β and IL-6 were increased in TN group ( P<0.05). Compared with TN group, the MWT was significantly increased at T 3-6, and the expression of P2X4R, p-p38 MAPK and BDNF in trigeminal ganglion was down-regulated, and the contents of TNF-α, IL-1β and IL-6 were decreased in TN+ 5-BDBD group ( P<0.05), and no significant change was found in the indexes mentioned above in TN+ DMSO group ( P>0.05). Conclusions:P2X4R is involved in the maintenance of trigeminal neuralgia in rats, which may be related to the activation of p38 MAPK/BDNF signaling pathway and the increase in inflammatory mediator release.

Anti-swelling and Analgesic Mechanism of Jianpi Tongluo Prescription from MAPKs Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo observe the anti-swelling and analgesic effects of Jianpi Tongluo prescription （JPTL） and to explore its mechanism initially. MethodA total of 120 ICR mice were divided into normal group， model group， JPTL low-， medium- and high-dose groups （5， 10， 20 g·kg-1） and positive drug （celecoxib， 0.03 g·kg-1） group， with 10 in each group （po，once a day）. Complete freund's adjuvant （CFA） was used to induce the model of chronic inflammatory pain， and xylene-induced ear swelling test， hot plate test and acetic acid writhing test were performed to observe the anti-swelling and analgesic effects of different doses of JPTL in these four acute and chronic models. Further， enzyme-linked immunosorbent assay （ELISA） was used to detect the expressions of prostaglandin E2 （PGE2）， interleukin-1β （IL-1β）， interleukin-6 （IL-6） and tumor necrosis factor-α （TNF-α） in serum and inflammatory paw of mice with chronic inflammatory pain， and the expressions of aquaporin 1 （AQP1）， aquaporin 3 （AQP3）， cyclooxygenase 1 （COX1）， cyclooxygenase 2 （COX2） and mitogen-activated protein kinases （MAPKs） in inflammatory paw were detected by Western blot， to explore the preliminary mechanism of JPTL. ResultCompared with the conditions in the normal group， there was a significant increase in the ear swelling of xylene-induced model mice， a shortened paw withdrawal latency in the hot plate test （P<0.01）. Compared with the model group， JPTL remarkably increased the inhibition rate of xylene-induced ear swelling （P<0.05， P<0.01）， prolonged the latency period of writhing caused by acetic acid and reduced the number of writhing （P<0.05， P<0.01）. Compared with normal group, the degree of feet swelling in chronic inflammatory pain mice was significantly increased， the threshold of mechanical pain was decreased and the threshold of cold pain was increased （P<0.05， P<0.01）， the protein contents of AQP1 and AQP3 in inflammatory feet were increased， and the contents of IL-1β， IL-6， TNF-α， PGE2 and COX2 in inflammatory feet were increased in serum and/or inflammatory feet. The protein expression levels of p-p38 MAPK， p-JNK and p-ERK in inflammatory feet were increased （P<0.01）. Compared with the model group， JPTL relieved paw swelling of mice with chronic inflammatory pain， elevated mechanical withdrawal threshold while decreased cold withdrawal threshold， with analgesia lasting for 4 h and the optimal time point for analgesia being 2 h after administration （P<0.05， P<0.01）. Moreover， JPTL down-regulated AQP1， AQP3， COX2， p-p38 MAPK， p-JNK and p-ERK in inflammatory paw of mice with chronic inflammatory pain and reduced IL-1β， IL-6， TNF-α， and PGE2 in serum and/or inflammatory paw， but it had no significant effect on COX1 （P<0.05， P<0.01）. ConclusionJPTL has anti-swelling and analgesic effects， and its mechanism is related to inhibiting the production of cytokines and inflammatory mediators via the down-regulation of MAPKs signaling pathway， which provides an experimental basis for the clinical application of JPTL.

Y-box-binding protein 1 mediates sorafenib resistance via the extracellular signal regulated-protein kinase pathway in hepatoma cells / 中华肝脏病杂志

Objective: To investigate the effect and possible mechanism of Y-box-binding protein 1 (YB-1) on sorafenib resistance in hepatoma cells. Methods: Lentiviral vectors with YB-1 overexpression and knockdown were constructed, respectively, to stimulate human hepatoma cell lines (HepG2 and Huh7) alone or in combination with sorafenib.The overexpression part of the experiment was divided into four groups: overexpression control group (Lv-NC), YB-1 overexpression group (Lv-YB-1), overexpression control combined with sorafenib resistance group (Lv-NC+sorafenib), YB-1 overexpression combined with sorafenib resistance group (Lv-YB-1 + sorafenib). The knockdown part of the experiment was also divided into four groups: knockdown control group (Lv-shNC), YB-1 knockdown group (Lv-shYB-1), knockdown control combined with sorafenib resistance group (Lv-shNC + sorafenib), YB-1 knockdown combined with sorafenib resistance group (Lv-shYB-1 + sorafenib). The occurrence of cell apoptosis was detected by TUNEL. The protein expression levels of phosphorylated (p)-ERK and ERK, key proteins in the extracellular regulatory protein kinase (ERK) signaling pathway, were detected by Western blot and quantified by ImageJ software. Subcutaneous tumorigenesis experiments were performed in nude mice. The effect of YB-1 on the efficacy of sorafenib was verified in vivo. The comparison between the two sets of data was carried out by an independent sample t-test. One-way ANOVA was used for comparisons between the three groups of data above. Results: Sorafenib had accelerated the occurrence of apoptosis in hepatoma cells, while YB-1 overexpression had inhibited cell apoptosis, and at the same time also inhibited the apoptosis-accelerating impact of sorafenib. On the contrary, YB-1 knockdown accelerated cell apoptosis and amplified the induction effect of sorafenib on apoptosis. Furthermore, sorafenib resistance had down-regulated p-ERK levels (HepG2: Lv-NC 0.685 ± 0.143, Lv-NC + sorafenib 0.315 ± 0.168, P < 0.05; Huh7: Lv-NC 0.576 ± 0.078, Lv-NC + sorafenib 0.150 ± 0.131, P < 0.01), whereas YB-1 overexpression had inhibited sorafenib resistance p-ERK reduction (HepG2: Lv-NC + sorafenib 0.315 ± 0.168, Lv-YB-1 + sorafenib 0.688 ± 0.042, P < 0.05; Huh7: Lv-NC + sorafenib 0.150 ± 0.131, Lv-YB-1 + sorafenib 0.553 ± 0.041, P < 0.05). YB-1 knockdown further increased sorafenib-induced p-ERK downregulation (HepG2: Lv-shNC + sorafenib 0.911 ± 0.252, Lv-shYB-1 + sorafenib 0.500 ± 0.201, P < 0.05; Huh7: Lv-shNC + sorafenib 0.577 ± 0.082, Lv-shYB-1 + sorafenib 0.350 ± 0.143, P < 0.05), which was further verified in naked mice (Lv-shNC + sorafenib 0.812 ± 0.279, Lv-shYB-1 + sorafenib 0.352 ± 0.109, P < 0.05). Conclusion: YB-1 mediates the occurrence of sorafenib resistance via the ERK signaling pathway in hepatoma cells.

Role of TBK1 in renal fibrosis in mice with acute kidney injury: relationship with endoplasmic reticulum stress / 中华麻醉学杂志

Objective:To evaluate the role of TANK-binding kinase-1 (TBK1) in renal fibrosis in mice with acute kidney injury (AKI) and relationship with endoplasmic reticulum stress.Methods:Twenty-four male wild-type C57BL/6 mice, aged 8-10 weeks, weighing 20-25 g, were divided into 4 groups ( n=6 each) using a random number table method: control group (group CON), group AKI, control plus TBK1 inhibitor group (group CON-GSK) and AKI plus TBK1 inhibitor group (group AKI-GSK). In group AKI and group AKI-GSK, folic acid 250 mg/kg was intraperitoneally injected to prepare AKI model.From the first day after folic acid injection, 1% dimethyl sulfoxide 20 ml/kg was intraperitoneally injected every other day in group AKI, and GSK8612 1.5 mg/kg was intraperitoneally injected every other day in group AKI-GSK, 7 times in total.In group CON and group CON-GSK, 1% dimethyl sulfoxide 20 ml/kg and GSK8612 1.5 mg/kg were intraperitoneally injected, respectively, every other day for 7 times in total.On the 14th day after injection of folic acid, the eyeball blood samples were taken to determine the concentrations of serum blood urea nitrogen (BUN) and creatinine (Cr), and the kidney tissues were also extracted, and the pathological results of renal tissue were observed by Sirius red staining, Masson staining and HE staining.The area of renal fibrosis was measured and the tubulointerstitial injury score was calculated.The expression of fibronectin, type I collagen and α-smooth muscle actin was detected by immunofluorescence.The expression of phosphorylated protein kinase R-like endoplasmic reticulum kinase (p-PERK), phosphorylated eukaryotic initiation factor 2α (p-eIF2α), activated transcription factor 4 (ATF4), C/EBP homologous protein (CHOP), phosphorylated inositol-requiring kinase 1α (p-IRE1α), tumor necrosis factor receptor-associated factor 2 (TRAF2), apoptosis-regulating signal kinase 1 (ASK1), caspase-12 and phosphorylated c-Jun N-terminal protein kinase (p-JNK) was detected by Western blot. Results:Compared with group CON, the serum BUN and Cr concentrations, area of renal fibrosis and renal tubulointerstitial injury score were significantly increased, and the expression of fibronectin, type I collagen, α-smooth muscle actin, p-PERK, p-eIF2α, ATF4, CHOP, p-IRE1α, TRAF2, ASK1, caspase-12, and p-JNK was up-regulated in group AKI and group AKI-GSK ( P<0.05), and no significant change was found in the indexes mentioned above in group CON-GSK ( P>0.05). Compared with group AKI, the serum BUN and Cr concentrations, area of renal fibrosis, and tubulointerstitial injury score were significantly decreased, and the expression of fibronectin, type I collagen, α-smooth muscle actin, p-PERK, p-eIF2α, ATF4, CHOP, p-IRE1α, TRAF2, ASK1, caspase-12, and p-JNK was down-regulated in group AKI-GSK ( P<0.05). Conclusions:TBK1 is involved in the process of renal fibrosis in mice with AKI, and the mechanism may be related to the promotion of endoplasmic reticulum stress.

Effects of Croton leaf on ERK1/2 protein expression in hippocampus of rats with cerebral ischemia reperfusion / 国际中医中药杂志

Objective:To analyze the effect of Croton leaf on ERK1/2 pathway in hippocampal of rats with cerebral ischemia-reperfusion.Methods:A total of 216 SD male rats were divided into sham operation group, model group, nimodipine group, low-dose, medium-dose and high-dose groups of croton leaf according to random nubmer table method, with 36 rats in each group. The MACO model of rats was prepared by the method of wire embolization. The high, medium and low dose groups were intragastrated with the water decoction 0.06 g/ml, 0.12 g/ml and 0.18 g/ml of Croton leaf; nimodipine group was intragastrated with nimodipine suspension 1.08 g/L; sham operation group and model group were intragastrated with equal volume of normal saline. Garcia JH score was used to conduct neurological function score, and HE staining was used to observe the morphology of hippocampal neurons after 7 days of continuous administration. Apoptosis of hippocampal CA3/DG region was detected by TUNEL assay. Western Blot was used to detect the expression of ERK1/2 and p-ERK1/2 proteins.Results:Compared with the model group at simultaneous point, the neurological function scores of low-dose, medium-dose and high-dose groups of Croton leaf increased ( P<0.01), the number of apoptotic cells decreased ( P<0.01), the expression of p-ERK1/2 / ERK1/2 [1 d: (0.22±0.03, 0.34±0.02, 0.46±0.01 vs. 0.19±0.02); 3 d: (0.38±0.02, 0.50±0.02, 0.68±0.02 vs. 0.27±0.02); 7 d: (0.29±0.03, 0.43±0.02, 0.59±0.02 vs. 0.21±0.03)] in hippocampus of the low-dose, medium-dose and high-dose groups of Croton leaf significantly increased ( P<0.01). Conclusion:Croton leaf could regulate the expression of ERK1/2 pathway protein upward, effectively improve the neural function and resist the apoptosis of hippocampal CA3/DG area of rats with cerebral ischemia-reperfusion injury.

Function of Polo-like kinase 1 and its research progress in tumor therapy / 国际外科学杂志

Protein kinases are key regulators of cellular function and constitute one of the largest and participate in orch estrating the vast majority of cellular activities, forming a criss-cross regulatong network. Kinases, which play a key role in regulating the activity of cellular proteins, are prime targets for anticancer drugs because their abnormal forms can promote the proliferation of tumor cells. Polo-like kinase-1 (Plk-1) is a member of the polo-like family of serine/threonine (Ser/Thr) kinases, which is involved in many aspects of the mitotic process that regulates cell proliferation, which is one of the key kinases of cell mitosis, whose overexpression is closely related to the occurrence and development of many human cancers. Drug development targeting Plk-1 may be one of the promising directions for the treatment of cancer. This review will summarize the structural features of Plk-1 and the cellular processes involved, as well as the rationale for anti-tumor therapy against Plk-1, the latest progress in inhibitor development and the latest strategies.

AMP-activated protein kinase signaling pathway: a potential therapeutic target for ischemic stroke / 国际脑血管病杂志

AMP-activated protein kinase (AMPK) is an energy sensor, which can regulate the energy metabolism of cells by regulating mitochondrial oxidation capacity and substrate utilization, affecting various pathways such as glucose and fatty acid transport. Recent studies have shown that energy metabolism disturbance is a "blasting fuse" leading to a series of secondary injuries after cerebral ischemia-reperfusion, including oxidative stress, acidosis, apoptosis, and excitotoxicity. AMPK participates in most pathophysiological processes of cerebral ischemia-reperfusion injury by regulating cellular energy metabolism. This article reviews the mechanism of action of AMPK signaling pathway in cerebral ischemia-reperfusion injury.

Remote ischemic preconditioning promotes mitochondrial biosynthesis and protects cerebral ischemia-reperfusion injury in rats via AMPK/PGC-1α signaling pathway / 国际脑血管病杂志

Objective:To investigate the protective mechanism of remote ischemic preconditioning (RIPC) on cerebral ischemia-reperfusion (I/R) injury in rats.Methods:Forty-eight SD rats were randomly divided into sham operation group, RIPC group, I/R group, RIPC+I/R group, and compound C group ( n=9 in each group). The neurological function score, cerebral infarction volume (TCC staining) and neuronal apoptosis rate (TUNEL staining) were measured. The activity of superoxide dismutase (SOD) 2 and malondialdehyde level in homogenate of brain tissue were detected. Expression levels of AMP-activated protein kinase (AMPK)/peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α signaling pathway-related proteins in brain tissue were detected by Western blot. Results:The neurological deficit score, cerebral infarction volume and neuron apoptosis rate in the I/R group were significantly higher than those in the sham operation group (all P<0.05). Compared with the I/R group, the neurological deficit score, cerebral infarction volume and neuron apoptosis rate in the RIPC+I/R group were significantly decreased (all P<0.05). Compared with the RIPC+I/R group, the neurological deficit score, cerebral infarction volume and neuron apoptosis rate in the compound C group were significantly increased (all P<0.05). Compared with the sham operation group, the SOD activity in the I/R group was significantly decreased, and the malondialdehyde content was significantly increased (all P<0.05). Compared with the I/R group, the SOD activity in the RIPC+I/R group was significantly increased, and the malondialdehyde content was significantly decreased (all P<0.05). Compared with the RIPC+I/R group, the SOD activity in the compound C group was significantly decreased, and the malondialdehyde content was significantly increased (all P<0.05). Compared with the sham operation group, the expressions of AMPK, p-AMPK, PGC-1α, nuclear respiratory factor (NRF)-1, mitochondrial transcription factor A (TFAM), SOD2, uncoupling protein 2 (UCP2), cytochrome C (CytC), and apoptosis-inducing factor (AIF) in the brain tissue of the I/R group were significantly increased (all P<0.05). Compared with the I/R group, the expressions of AMPK, p-AMPK, PGC-1α, NRF-1, TFAM, SOD2 and UCP2 in the ischemic brain tissue of the RIPC+I/R group were significantly increased, while the expressions of CytC and AIF were significantly decreased (all P<0.05). Compared with the RIPC+I/R group, the expressions of AMPK, p-AMPK, PGC-1α, NRF-1, TFAM, SOD2 and UCP2 in the brain tissue of the compound C group were significantly decreased, while the expressions of CytC and AIF were significantly increased (all P<0.05). Conclusions:RIPC has a protective effect on I/R injury. Its mechanism may be associated with the activation of AMPK/PGC-1α signaling pathway and maintaining mitochondrial biogenesis.

Role of PKA-CREB signaling pathway in sevoflurane-induced reduction of cognitive impairment caused by cardiopulmonary bypass in rats / 中华麻醉学杂志

Objective:To evaluate the role of protein kinase A (PKA)-cyclic adenosine monophosphate response element binding protein (CREB) signaling pathway in sevoflurane-induced reduction of cardiopulmonary bypass (CPB)-induced cognitive impairment in rats.Methods:Forty healthy male Sprague-Dawley rats, aged 4 months, weighing 300-350 g, were divided into 4 groups ( n=10 each) using a random number table method: control group (group C), group CPB, CPB+ sevoflurane group (group CS) and CPB+ sevoflurane+ PKA inhibitor H89 group (group CSH). After H89 5 μl was injected into the lateral ventricle in group CSH, the rats in group CS and group CSH were exposed to 2.4% sevoflurane for 1 h, and then the CPB model of beating heart without blood priming for 60 min was developed in CPB, CS and CSH groups.The autonomic movement ability was evaluated using the open field test at 2nd day after CPB.Morris water maze test was used to assess the cognitive function at 3rd day after CPB.The rats were sacrificed after the Morris water maze test, the brain was removed and the hippocampal tissues were isolated for determination of the apoptosis rate of hippocampal neurons (by flow cytometry) and expression of PKA, phosphorylated CREB (p-CREB) and brain-derived neurotrophic factor (BDNF) (by Western blot). Results:There was no significant difference in movement speed, distance and time of staying at the central region among the four groups ( P>0.05). Compared with group C, the escape latency was significantly prolonged, the number of crossing the original platform was reduced, the time of staying at the original platform quadrant was shortened, the apoptosis rate of hippocampal neurons was increased, and the expression of PKA, p-CREB and BDNF was down-regulated in the other three groups ( P<0.05). Compared with group CPB, the escape latency was significantly shortened, the number of crossing the original platform was increased, the time of staying at the original platform quadrant was prolonged, the apoptosis rate of hippocampal neurons was decreased, and the expression of PKA, p-CREB and BDNF was up-regulated in group CS ( P<0.05), and no significant change was found in the indexes mentioned above in group CSH ( P>0.05). Compared with group CS, the escape latency was significantly prolonged, the number of crossing the original platform was reduced, and the time of staying at the original platform quadrant was shortened, the apoptosis rate of hippocampal neurons was increased, and the expression of PKA, p-CREB and BDNF was down-regulated in group CSH ( P<0.05). Conclusions:Sevoflurane can reduce the apoptosis in hippocampal neurons by activating PKA-CREB signaling pathway, and thus reducing the cognitive impairment induced by CPB in rats.

Mechanism of levosimendan on acute kidney injury after cardiopulmonary resuscitation in rats / 中华急诊医学杂志

Objective:To investigate the mechanism of levosimendan on acute kidney injury after cardiopulmonary resuscitation (CPR) in rats.Methods:Twenty-five healthy adult male SD rats were randomly divided into three groups: control group ( n=5), levosimendan group ( n=10) and experimental group ( n=10). A cardiac arrest-cardiopulmonary resuscitation model was established using smothering method in the experimental group and levosimendan group. The levosimendan group was treated with levosimandan during and after resuscitation, while the experimental group was given equivalent volume of saline solution during and after resuscitation, and the control group was only given equivalent volume of saline without performance of CPR. The rats in the three groups were sacrificed at 6 h after resuscitation. The serum and kidney tissue samples were collected. Serum biochemical indicators [serum creatinine (Scr), blood urea nitrogen (Bun), interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α)] were measured. HE staining and Paller score were used to identify the degree of kidney damage. Apoptosis was estimated by TUNEL staining. Western blot was used to detect the expression levels of phosphorylation of extracellular regulated protein kinases (p-ERK). One-way analysis of variance was used to compare the mean values of normally distributed measurement data between groups. Comparisons between groups were performed using the least significant difference t-test. Results:Scr (85.02±1.31) μmol/L, Bun (7.36±0.13) mmol/L, Paller score (7.3±0.2), IL-1β (302.20±17.35) pg/mL, IL-6 (564.60±23.24) pg/mL and TNF-α (1346±83.73) pg/mL in the experimental group were significantly higher than those of the control group [(15.94±0.96) μmol/L, (2.95±0.18) mmol/L, (0.7±0.2), (7.27±0.44) pg/mL, (51.30±2.87) pg/mL, and (10.39±0.52) pg/mL] (all P<0.01). Compared with the experimental group, Scr (63.88±2.01) μmol/L, Bun (5.45±0.47) mmol/L, paller score (4.8±0.2), IL-1β (78.61±3.66) pg/mL, IL-6 (297.90±13.64) pg/mL and TNF-α (276.2±20.18) pg/mL were significantly decreased in the levosimendan group (all P<0.01). TUNEL staining showed that levosimendan could improve the apoptosis of renal cells ( P<0.01). The expression of p-ERK protein in the levosimendan group was significantly higher than that in the experimental group ( P<0.01). Conclusions:Lovosimendan could attenuate acute kidney injury following cardiac arrest and cardiopulmonary resuscitation via suppression apoptosis. The mechanism of levosimendan protective effect might be associated with activation of ERK signaling pathway.

Development of small molecule extracellular signal-regulated kinases (ERKs) inhibitors for cancer therapy

The mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathway is widely activated by a variety of extracellular stimuli, and its dysregulation is associated with the proliferation, invasion, and migration of cancer cells. ERK1/2 is located at the distal end of this pathway and rarely undergoes mutations, making it an attractive target for anticancer drug development. Currently, an increasing number of ERK1/2 inhibitors have been designed and synthesized for antitumor therapy, among which representative compounds have entered clinical trials. When ERK1/2 signal transduction is eliminated, ERK5 may provide a bypass route to rescue proliferation, and weaken the potency of ERK1/2 inhibitors. Therefore, drug research targeting ERK5 or based on the compensatory mechanism of ERK5 for ERK1/2 opens up a new way for oncotherapy. This review provides an overview of the physiological and biological functions of ERKs, focuses on the structure-activity relationships of small molecule inhibitors targeting ERKs, with a view to providing guidance for future drug design and optimization, and discusses the potential therapeutic strategies to overcome drug resistance.

Study on the relationship between relieving energy crisis in myofascial trigger points with An-Pressing manipulation and AMPK/PGC-1α pathway activation / 针灸推拿医学（英文版）

Objective: To explore the mechanism of An-Pressing manipulation in relieving energy crisis in chronic myofascial trigger points (MTrPs) by observing the effects of An-Pressing manipulation on adenosine triphosphate (ATP), adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)/peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) pathway and mitochondrial ultrastructure of skeletal muscle cells in MTrPs rats. Methods: Forty-eight male Sprague-Dawley rats were randomly divided into a blank group, a model group, a lidocaine group, and an An-Pressing manipulation group, with 12 rats in each group. The model group, lidocaine group and An-Pressing manipulation group were used to replicate the MTrPs rat model by blunt shock and centrifugal motion method. After modeling, the An-Pressing manipulation group was subjected to 7 times An-Pressing manipulation, once every other day; the lidocaine group was treated with 3 times of injection of lidocaine at the MTrPs, once every 6 d. The blank group and the model group were fed normally without intervention. After the intervention, local muscle tissue was taken to detect the content of ATP and the expression of AMPK, phosphorylated AMPK (phospho-AMPK), PGC-1α, and glucose transporter 4 (GluT4), and the ultrastructure of mitochondria was observed under an electron microscope. Results: Compared with the blank group, the ATP content in the model group was decreased (P<0.05), the protein expression levels of phospho-AMPK, PGC-1α, and GluT4 and the ratio of phospho-AMPK to AMPK were decreased (P<0.05); under the electron microscope, the number of mitochondria decreased, and they were deformed, small in volume, and had deformed cristae. Compared with the model group, the ATP contents in the An-Pressing manipulation group and the lidocaine group were increased (P<0.05), and the protein expression levels of phospho-AMPK, PGC-1α, and GluT4 and the ratio of phospho-AMPK to AMPK were increased (P<0.05); under the electron microscope, the number of mitochondria increased, the shape and size of the mitochondria were basically normal, and the cristae could be seen. Compared with the lidocaine group, phospho-AMPK and the ratio of phospho-AMPK to AMPK in the An-Pressing manipulation group were increased (P<0.05); under the electron microscope, the numbers of mitochondria were similar, and the shape and size of the mitochondria were basically normal without swelling, and the cristae could be observed. Conclusion: An-Pressing manipulation can increase the ATP content in MTrPs tissue, improve the expression levels of PGC-1α and GluT4 proteins and the ratio of phospho-AMPK to AMPK; its mechanism may relate to the activation of AMPK/PGC-1α signaling pathway to promote the repair of mitochondrial damages.

Effects of neutrophil extracellular traps on proliferation and apoptosis of human amniotic epithelial cells and its possible mechanisms / 中华围产医学杂志

Objective:To investigate the effects of neutrophil extracellular traps (NETs) on the proliferation and apoptosis of human amniotic epithelial cells.Methods:NETs were induced in vitro from the neutrophil cells obtained from the peripheral blood of normal pregnant women before elective cesarean section at full-term. Human amniotic epithelial cell lines (WISH cells) were cultured in vitro, and were divided into four groups:(1) control group: without any stimulus; (2) NETs group: WISH cells were stimulated with NETs (500 ng/ml); (3) NETs+SB203580 (p38 kinase inhibitor) group: WISH cells were pretreated with SB203580 (5 μmol/L) for 30 min and then NETs (500 ng/ml) was added; (4) SB203580 group: only SB203580 was added. After stimulating for 48 h, cell proliferation assay, lactate dehydrogenase(LDH) assay, and flow cytometry assay were used to detect the cell proliferation rate, LDH level of cell supernatant, and cell apoptosis rate among different groups. The results were analyzed and compared using one-way analysis of variance and LSD- t test. Results:(1) Cell proliferation: The cell proliferation ratio in the NETs group was lower than that in the control group [(9.379±0.775)% vs (36.560±1.208)%, LSD- t=20.78, P<0.001]; and the figure in the NETs+SB203580 group [(27.920±0.926)%] was higher than that in the NETs group (LSD- t=14.18, P<0.001). (2)LDH: There was an increased LDH level in the cell supernatant of the NETs group compared with the control group (1.518±0.038 vs 0.274±0.004, LSD -t=44.25, P<0.05), and the LDH level in the NETs+SB203580 group (0.857±0.009) was decreased than that in the NETs group (LSD -t=23.51, P<0.001). (3) Apoptosis: Compared with the control group, the cell apoptosis level of the NETs group was increased [(14.290±0.141)% vs (10.110±0.044)%, LSD- t=21.76, P<0.001]; but that in the NETs+SB203580 group [(10.500±0.218)%] was lower than in the NETs group (LSD- t=19.70, P<0.001). Conclusion:p38/mitogen-activated protein kinases signaling pathway may be involved in the process of NETs, inhibiting proliferation and promoting apoptosis of human amniotic epithelial cells.

Role of AMPK/p38 MAPK/Nrf2 signaling pathway in myocardial ischemia-reperfusion injury in diabetic rats / 中华麻醉学杂志

Objective:To evaluate the role of adenosine monophosphate-dependent protein kinase/p38 mitogen-activated protein kinase/nuclear factor E2-associated factor 2 (AMPK/p38 MAPK/Nrf2) pathway in myocardial ischemia-reperfusion (I/R) injury in diabetic rats.Methods:Clean-grade healthy Sprague-Dawley male rats, aged 2-3 months, weighing 220-280 g, were fed with a high fat diet, and 1% streptozotocin 50 mg/kg was intraperitoneally injected for 4 consecutive days to develop the model of diabetes mellitus.Thirty diabetic rats were divided into 3 groups ( n=10 each) using the random number table method: sham operation group (sham group), myocardial I/R group (I/R group), and AMPK inhibitor compound C+ myocardial I/R group (C+ I/R group). The model of myocardial I/R injury was developed by ligation of the left anterior descending coronary artery for 30 min followed by 120 min reperfusion.Compound C 0.5 mg/kg was injected via the caudal vein at 30 min before ischemia in C+ I/R group, while the equal volume of normal saline was given instead in Sham group and I/R group.At 120 min of reperfusion, the percentage of myocardial infarct size was calculated, the serum concentrations of creatine kinase isoenzymes (CK-MB) and lactic dehydrogenase (LDH) were determined by enzyme-linked immunosorbent assay, the levels of glutathione (GSH), superoxide dismutase (SOD) and reactive oxygen species (ROS) in myocardial tissues were measured by enzyme-linked immunosorbent assay, and the expression of AMPK, phosphorylated AMPK (p-AMPK), phosphorylated p38 MAPK (p-p38 MAPK), Nrf2 and heme oxygenase-1 (HO-1) in myocardium was determined by Western blot. Results:Compared with Sham group, the percentage of myocardial infarct size and serum CK-MB and LDH levels were significantly increased, the levels of GSH and SOD in myocardial tissues were decreased, ROS level was increased, and the expression of AMPK, p-AMPK, p-p38 MAPK, Nrf2 and HO-1 was up-regulated in I/R group ( P<0.05). Compared with I/R group, the percentage of myocardial infarct size and serum CK-MB and LDH levels were significantly increased, the levels of GSH and SOD in myocardial tissues were decreased, ROS level was increased, and the expression of AMPK, Nrf2 and HO-1 was down-regulated in C+ I/R group ( P<0.05). Conclusions:AMPK/p38 MAPK/Nrf2 signaling pathway is involved in the mechanism of endogenous antioxidant stress during myocardial I/R in diabetic rats.

Salvadora persica extract attenuates cyclophosphamide-induced hepatorenal damage by modulating oxidative stress, inflammation and apoptosis in rats / 中西医结合学报

OBJECTIVE@#Salvadora persica (SP) is used as a food additive and is a common ingredient in folk medicine. This study investigates the antioxidant, anti-inflammatory, and beneficial effects of SP against cyclophosphamide (CYP) toxicity in rats.@*METHODS@#In a 10-day study, 32 male rats were equally allocated into 4 groups (8 rats/group) as follows: the normal control (NC group), normal rats that only received oral aqueous extract of SP (100 mg/[kg·d]; SP group), animals treated with intraperitoneal CYP injections (30 mg/[kg·d]; CYP group), and the CYP + SP group that concurrently received CYP with SP aqueous extract. Serum samples were collected to measure the liver and renal biochemical profiles, as well as antioxidant and oxidative stress markers and the concentrations of interleukin-1β (IL-1β), IL-6, IL-10, tumor necrosis factor-α (TNF-α), nuclear factor-κB (NF-κB) and adenosine 5'-monophosphate-activated protein kinase (AMPK). Hepatic and renal tissues were also harvested for histopathology and to measure apoptosis using the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling technique, alongside tissue levels of oxidative stress markers.@*RESULTS@#Liver enzymes, total bilirubin, creatinine and urea, as well as serum IL-1β, IL-6, TNF-α and NF-κB increased significantly, whilst total protein, albumin, calcium, IL-10 and AMPK declined in serum of the CYP group relative to the NC group. The hepatorenal concentrations of glutathione, glutathione peroxidase and catalase declined markedly in the CYP group, whereas malondialdehyde, protein adducts, and apoptosis index increased compared with the NC group. By contrast, the hepatorenal biochemistry and apoptosis index of the SP group were comparable to the NC group. Interestingly, the CYP + SP group had significant improvements in the liver and renal biochemical parameters, enhanced anti-oxidative and anti-inflammatory effects, and marked declines in hepatic and renal apoptosis relative to the CYP group. Moreover, all monitored parameters were statistically indistinguishable between the CYP + SP group and the NC group.@*CONCLUSION@#This study suggests that the aqueous extract of SP could be a potential remedy against CYP-induced hepatorenal damage and may act by modulating the AMPK/NF-κB signaling pathway and promoting anti-oxidative and anti-inflammatory activities.