Ethanol extract from Cortex Albiziae attenuates mouse acute liver injury induced by carbon tetrachloride via modulation of NF-κB pathway

AIM:To investigate the protective effect of ethanol extract from Cortex Albiziae on acute liver injury, and to explore its possible mechanism. METHODS:Acute liver injury in mice was induced by single intraperitoneal injection of 25% carbon tetrachloride (olive oil solubilization). The effective parts of ethanol extract from Cortex Albizziae against acute liver injury were screened. The pathological changes of the liver tissues were examined by pathological sections with HE staining. The activity of total superoxide dismutase (T-SOD) and the content of malondialdehyde (MDA) of the liver tissues were detected, the serum levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were mea-sured by ELISA, and the protein expression levels of NF-κB p65, Bcl-2 and Bax in the liver cells of the mice in each group were determined by Western blot. RESULTS:Compared with model group, the serum levels of AST and ALT in low-dose n-butanol phase of ethanol extract from Cortex Albiziae (AB-L, 4 mg·kg^-1·d^-1) group and high-dose n-butanol phase of ethanol extract from Cortex Albiziae (AB-H, 8 mg·kg^-1·d^-1) group were significantly decreased. The necrosis extent and degree of the hepatocytes and infiltration of inflammatory cells were significantly lower than that in model group. Compared with model group, the serum levels of TNF-α and IL-6 in AB-H group and AB-L group were significantly decreased (P<0.05). The protein level of NF-κB p65 in the nuclei of mouse liver cells in AB-H group and AB-L group were also decreased significantly (P<0.05). Compared with model group, the protein expression of Bax was decreased, the protein expression of Bcl-2 was increased, and the Bcl-2/Bax ratio was increased in AB-L group and AB-H group. CONCLUSION:The n-butanol phase of ethanol extract from Cortex Albiziae may protect the liver by reducing the activation of NF-κB p65, inhibiting the excessive release of inflammatory cytokines IL-6 and TNF-α, and decreasing hepatocyte apoptosis via regulating Bcl-2 and Bax expression.     

Hesperetin attenuates hypoxia/reoxygenation-induced apoptosis in H9c2 cells via inhibition of calcium overload

AIM: To investigate the effect of hesperetin on hypoxia/reoxygenation (H/R)-induced apoptosis in the H9c2 cells and to clarify the underlying mechanism. METHODS: The H/R model was established and the H9c2 cells were pretreated with hesperetin for 4 h. The cell viability and cell damage were measured by CCK-8 assay and lactate dehydrogenase (LDH) detection. The apoptosis was analyzed by Hoechst 33258 staining and flow cytometry. The intracellular calcium fluorescence intensity was measured by fluorescence microscopy and flow cytometry. The calcium-ATPase activity and the level of adenosine triphosphate (ATP) were measured by ELISA. The mitochondrial membrane potential was measured by JC-1 staining. The protein expression levels of Bcl-2, Bax and cytochrome C (Cyt-C) were determined by Western blot. RESULTS: Hesperetin reduced the apoptosis of the H9c2 cells induced by H/R, decreased intracellular Ca²⁺ fluorescence intensity, elevated Ca²⁺-ATPase activity, inhibited the mitochondrial membrane potential depolarization and increased the level of ATP (P<0.05). In addition, hesperetin significantly reduced the release of Cyt-C protein from mitochondria to cytoplasma and increased the Bcl-2/Bax ratio (P<0.05). After using the calcium ion inhibitor nimodipine, the percentage of the cells with mitochondrial membrane depolarization was decreased, the ATP level was increased and the protein expression of mitochondrion-related apoptosis molecules were decreased (P<0.05). CONCLUSION: Hesperetin reduces the apoptosis of the H9c2 cells induced by H/R, which may be related to inhibition of calcium overload and improvement of mitochondrial function.     

Cigarette dust particles induced lung function injury of chronic obstructive pulmonary disease in mice

AIM: To investigate the pathogenesis of chronic obstructive disease (COPD) in mice by using nasal drip of cigarette dust particles (DSP) induced pulmonary function damage model.METHODS: BALB/c mice were randomly divided into control group, LPS 100 mg/L group, DSP 0.75 mL/L group, DSP 1.5 mL/L group and DSP 3 mL/L group for 30 days. The method of nasal drip was used for 30 days to establish the COPD model. Rrs, Ers, Crs, Est, Cst, P-3/8Rn, P-3/8G and P-3/8H were measured for evaluating lung function of the mice in each group by the method of FlexiVent. The effect on the increase of airway resistance induced by methacholine (Mach) was determined using main bronchial rings by Myograph method. The HE, Masson and Resorcinol fuchsin staining of mouse tracheas and lung tissues were conducted. RESULTS: Continuous nasal drip with DSP for 30 days increased Rrs, Ers, Est, P-3/8Rn and decreased Crs, Cst, P-3/8G and P-3/8H in the mice. DSP significantly shifted the dose-effect curve of tracheal contraction induced by Mach to the left, increased the sensitivity of the airway to Mach, and significantly increased the maximal contractile airway effect of Mach. Exposure to DSP caused fibrosis of airway subepithelial, deposition of collagen in the airway basement membrane under the reticular plate, induced reticular plate thickening, pulmonary bronchial lumen serious deformation, and the inflammatory cell infiltration in the lung of mice. Significantly increased alveolar wall muscle fibers and collagen fibers were also observed. CONCLUSION: The lung function and pathomorphological changes of COPD mice induced by 30 days nasal drip of cigarette dust particles were similar to those of human COPD.     

Effects of DHRS3 in C2C12 Myoblast Differentiation and Mouse Skeletal Muscle Injury

Myoblast differentiation is an essential process during skeletal muscle development. C2 C12 myoblast is a commonly used experimental model to study muscle cell differentiation in vitro. Dehydrogenase/reductase(SDR family) member 3(DHRS3) is a highly conserved member in short-chain alcohol dehydrogenase/reductase superfamily and has been shown to be involved in the metabolism of retinol. Previous experimental results showed that the expression of DHRS3 increased significantly during the differentiation of myoblasts differentiation. However, the effect of DHRS3 on mouse muscle cell differentiation was unclear. The objective of current study was to determine if DHRS3 affected muscle cell differentiation, and if DHRS3 was involved in muscle regeneration. Protein expression was determined by western blot and immunofluorescence analysis. The activation and inhibition of DHRS3 increased and decreased C2 C12 myoblast differentiation respectively, which indicated that DHRS3 could affect C2 C12 myoblast differentiation. DHRS3 expression was significantly changed during muscle regeneration, with the regeneration of muscle injury, the expression of DHRS3 tended to increase first and then decrease. It suggested that DHRS3 might be involved in muscle regeneration. In summary, this study confirmed the involvement of DHRS3 in C2 C12 myoblast differentiation and mouse skeletal muscle regeneration and provided a theoretical basis for further elucidating the molecular mechanism of muscle development.     

不同水分管理旱直播水稻生长生理与节水效应

为了探讨东北黑土区水稻高效节水种植模式,于2017年在黑龙江省庆安县采用测坑微区试验,研究了旱直播对水稻光合特性、各器官生物产量、干物质累积速率、根冠比、伤流强度、产量水分利用效率(WUEy)、叶片水分利用效率(WUEl)和产量因子等的影响。试验设置了3个处理:滴灌旱直播(DH)、漫灌旱直播(MH)和常规插秧淹灌(CK),并以CK处理作为对照。结果表明:DH与MH处理的净光合速率Pn(分蘖末期除外)、蒸腾速率Tr、气孔导度Gs、以及叶、鞘、茎、穗等冠部干物质累积量、冠部干物质累积速率(分蘖中期至末期除外)、冠部最大累积速率在整个生育期均低于CK,但WUEl、根部干物质累积量(分蘖前期和中期除外)、根部干物质累积速率、根系活力(分蘖中期与拔节孕穗期除外)均高于CK。3个处理的胞间CO2浓度Ci整个生育期波动幅度不大。根部和总干物质最大累积速率及各生育期根冠比以DH最大,CK最小。DH与MH处理的千粒质量和结实率较CK下降不显著(P0.05),穗长和穗粒数下降显著(P0.05),有效穗数上升显著(P0.05)。DH较CK、MH分别节省灌溉用水63.88%和39.52%,WUEy分别提高2.66倍和1.64倍。滴灌旱直播种植不仅大幅度减少了灌溉用水量,显著提高了水稻的WUEy,而且具有较为可观的经济效益和显著的社会效益。研究结果可为东北黑土区水稻种植模式的选取提供技术支撑,对保障黑土区农业水土资源可持续利用具有重要意义。     

近20年来霜冻害的发生与防御研究进展

分析了近20年来霜冻害的发生趋于严重的原因，提出了相应的防御对策措施。重点概述了近年来霜冻防御技术研究的新进展。     

倒春寒危害软籽石榴树的温度及受害情况研究

以突尼斯软籽石榴为试材,在倒春寒发生前2 d开始持续监测石榴树冠层温度,倒春寒结束后调查石榴树受倒春寒危害的临界低温及寒害症状。结果表明,软籽石榴树春季生长期间,岭地、沟地和台地石榴树冠层温度降至1.4℃、-0.1℃、2.3℃,气象预报低温低于6.4℃时,石榴树芽和新梢发生低温寒害,芽尖焦枯发黑,芽体展叶受阻;新梢幼叶扭曲畸形,叶缘焦枯。     

宜昌市柑橘冻害发生的气象特点及柑橘不同品种在冻害中表现和冻后恢复比较

【研究目的】全球升温趋势之下,极端温度变幅加大和低温造成的灾害性天气频率不减反增,2008、2011和2012宜昌柑橘产区部分或大面积发生不同程度柑橘冻害。本研究旨在增强人们对于冻害发生天气情况的了解,为柑橘产区品种规划及防寒减灾提供参考资料【方法】通过对宜昌市夷陵区历次柑橘冻害发生的气象资料统计和冻后实际调研情况分析,对最近几年冻害发生过程中不同柑橘种类和品种的表现及冻后恢复情况进行比较。【结果】发现历次大冻均发生于1月5日至1月31日之间,冻害程度与低温强度及低温持续时间呈现正相关。比较了柚、杂柑、椪柑、温州蜜柑和甜橙等不同柑橘种类在冻害中的表现,结果表明,受冻程度由重到轻依次为：杂柑→柚类→橙类→椪柑→温州蜜柑,离大水体远的果园受冻严重;坡向、坡位对冻害程度有影响。冻后恢复情况与树体冻害程度和冻后恢复能力有关,甜橙和柚冻害较重,但恢复能力较强,椪柑受冻虽然较甜橙和柚为轻,但冻后恢复较慢,而温州蜜柑冻害发生轻、冻后恢复也最快。【结论】在柑橘栽培北缘地区,因地制宜选择适宜品种、合理进行规划布局对柑橘产业健康发展极为重要。     

UV-C处理对水蜜桃果实冷害及贮藏品质的影响

为了缓解水蜜桃果实采后冷藏保鲜对果实品质的负面影响,达到更好的保鲜效果,以江苏省张家港市的凤凰水蜜桃（Prunus persica)为实验材料,研究了不同剂量（0.5kJ/m2、1kJ/m2、1.5kJ/m2）UV-C对低温（3℃?℃）条件下水蜜桃果实冷害和品质的影响。实验结果表明：三种剂量的UV-C处理对水蜜桃均能有效减少果实的褐变,保存果实的可溶性固形物（TSS）,并明显延缓了丙二醛（MDA）、多酚氧化酶（PPO酶）的上升趋势;处理之间没有明显的效果差异,但1.5 kJ/m2处理的硬度值在5-20d之间均显著大于CK组（P<0.05）,表现出更好的抗软化能力;另外,UV-C处理易使果实相对电导率加速升高,该趋势随照射剂量的增大而增强。