Plants have acquired sophisticated stress response systems to adapt to changing environments. It is important to understand plants＇ stress response mechanisms in the effort to improve crop productivity under stressfu...Plants have acquired sophisticated stress response systems to adapt to changing environments. It is important to understand plants＇ stress response mechanisms in the effort to improve crop productivity under stressful conditions. The AP2/ERF transcription factors are known to regulate diverse processes of plant development and stress responses. In this study, the molecular characteristics and biological functions of AP2/ERFs in a variety of plant species were analyzed. AP2/ERFs, especially those in DREB and ERF subfamilies, are ideal candidates for crop improvement because their overexpression enhances tolerances to drought, salt, freezing, as well as resistances to multiple diseases in the transgenic plants. The comprehensive analysis of physiological functions is useful in elucidating the biological roles of AP2/ERF family genes in gene interaction, pathway regulation, and defense response under stress environments, which should provide new opportunities for the crop tolerance engineering.展开更多
Background Berberine is one of the main constituents of Coptidis rhizoma （CR） and Cortex phellodendri. In this study, we investigated the beneficial effects of berberine on renal function and its possible mechanisms...Background Berberine is one of the main constituents of Coptidis rhizoma （CR） and Cortex phellodendri. In this study, we investigated the beneficial effects of berberine on renal function and its possible mechanisms in rats with diabetic nephropathy （DN）. Methods Male Wistar rats were divided into three groups： normal, diabetic model, and berberine treatment groups. Rats in the diabetic model and berberine treatment groups were induced to diabetes by intraperitonal injection with streptozotocin （STZ）. Glomerular area, glomerular volume, fasting blood glucose （FBG）, blood urea nitrogen （BUN）, serum creatinine （Cr） and urine protein for 24 hours （UP24h） were measured using commercially available kits. Meanwhile, the activity of superoxide dismutase （SOD）, content of malondialdehyde （MDA） in serum, activity of aldose reductase （AR） and the expression of AR mRNA and protein in kidney were detected by different methods. Results The results showed that oral administration of berberine （200 mg·kg^-1·d^-1） significantly ameliorated the ratio of kidney weight to body weight. Glomerular area, glomerular volume, FBG, BUN, Cr and UP24h were significantly decreased in the berberine treatment group compared with the diabetic model group （P〈0.05）. Berberine treatment significantly increased serum SOD activity and decreased the content of MDA compared with diabetic model group （P 〈0.05）. AR activity as well as the expression of AR mRNA and protein in the kidney was markedly decreased in the berberine treatment group compared with diabetic model group （P 〈0.05）. Conclusion These results suggested that berberine could ameliorate renal dysfunction in DN rats through controlling blood glucose, reduction of oxidative stress and inhibition of the activation of the polyol pathway.展开更多
Epalrestat is a noncompetitive and reversible aldose reductase inhibitor used for the treatment of diabetic neuropathy. This study assumed that epalrestat had a protective effect on diabetic peripheral nerve injury by...Epalrestat is a noncompetitive and reversible aldose reductase inhibitor used for the treatment of diabetic neuropathy. This study assumed that epalrestat had a protective effect on diabetic peripheral nerve injury by suppressing the expression of aldose reductase in peripheral nerves of diabetes mellitus rats. The high-fat and high-carbohydrate model rats were established by intraperitoneal injection of streptozotocin. Peripheral neuropathy occurred in these rats after sustaining high blood glucose for 8 weeks. At 12 weeks after streptozotocin injection, rats were intragastrically administered epalrestat 100 mg/kg daily for 6 weeks. Transmission electron microscope revealed that the injuries to myelinated nerve fibers, non-myelinated nerve fibers and Schwann cells of rat sciatic nerves had reduced compared to rats without epalrestat administuation. Western blot assay and immunohistochemical results demonstrated that after intervention with epalrestat, the activities of antioxidant enzymes such as superoxide dismutase, catalase and glutathione peroxidase gradually increased, but aldose reductase protein expression gradually diminished. Results confirmed that epalrestat could protect against diabetic peripheral neuropathy by relieving oxidative stress and suppressing the polyol pathway.展开更多
In diabetes mellitus, the polyol pathway is highly active and consumes approximately 30% glucose in the body. This pathway contains 2 reactions catalyzed by aldose reductase(AR) and sorbitol dehydrogenase, respectivel...In diabetes mellitus, the polyol pathway is highly active and consumes approximately 30% glucose in the body. This pathway contains 2 reactions catalyzed by aldose reductase(AR) and sorbitol dehydrogenase, respectively. AR reduces glucose to sorbitol at the expense of NADPH, while sorbitol dehydrogenase converts sorbitol to fructose at the expense of NAD+, leading to NADH production. Consumption of NADPH, accumulation of sorbitol, and generation of fructose and NADH have all been implicated in the pathogenesis of diabetes and its complications. In this review, the roles of this pathway in NADH/NAD+redox imbalance stress and oxidative stress in diabetes are highlighted. A potential intervention using nicotinamide riboside to restore redox balance as an approach to fighting diabetes is also discussed.展开更多
基金supported by the National Transgenic Key Project of MOA(201 1ZX08002-002 and 2009ZX08009-083B)
文摘Plants have acquired sophisticated stress response systems to adapt to changing environments. It is important to understand plants＇ stress response mechanisms in the effort to improve crop productivity under stressful conditions. The AP2/ERF transcription factors are known to regulate diverse processes of plant development and stress responses. In this study, the molecular characteristics and biological functions of AP2/ERFs in a variety of plant species were analyzed. AP2/ERFs, especially those in DREB and ERF subfamilies, are ideal candidates for crop improvement because their overexpression enhances tolerances to drought, salt, freezing, as well as resistances to multiple diseases in the transgenic plants. The comprehensive analysis of physiological functions is useful in elucidating the biological roles of AP2/ERF family genes in gene interaction, pathway regulation, and defense response under stress environments, which should provide new opportunities for the crop tolerance engineering.
文摘在糖尿病肾病(diabetic nephropathy,DN)发生、发展过程中机体内活性氧簇(reactive oxygen species,ROS)生成增多导致肾组织OS损伤的发生;其形态学特征主要表现为肾小球和肾小管固有细胞结构和功能的改变。肾组织OS调控途径涉及胞内多条信号通路,其中,p38丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)信号通路和腺苷酸活化蛋白激酶(adenosine monophosphate-activated protein kinase,AMPK)信号通路作为多种抗氧化物质的靶点而发挥着重要功能。中药复方或单味中药提取物对DN肾组织OS损伤的干预作用包括"调控ROS和抗氧化物质,减少晚期糖基化终末产物形成,抑制生长因子表达,影响胞内信号通路活性"等。
文摘Background Berberine is one of the main constituents of Coptidis rhizoma （CR） and Cortex phellodendri. In this study, we investigated the beneficial effects of berberine on renal function and its possible mechanisms in rats with diabetic nephropathy （DN）. Methods Male Wistar rats were divided into three groups： normal, diabetic model, and berberine treatment groups. Rats in the diabetic model and berberine treatment groups were induced to diabetes by intraperitonal injection with streptozotocin （STZ）. Glomerular area, glomerular volume, fasting blood glucose （FBG）, blood urea nitrogen （BUN）, serum creatinine （Cr） and urine protein for 24 hours （UP24h） were measured using commercially available kits. Meanwhile, the activity of superoxide dismutase （SOD）, content of malondialdehyde （MDA） in serum, activity of aldose reductase （AR） and the expression of AR mRNA and protein in kidney were detected by different methods. Results The results showed that oral administration of berberine （200 mg·kg^-1·d^-1） significantly ameliorated the ratio of kidney weight to body weight. Glomerular area, glomerular volume, FBG, BUN, Cr and UP24h were significantly decreased in the berberine treatment group compared with the diabetic model group （P〈0.05）. Berberine treatment significantly increased serum SOD activity and decreased the content of MDA compared with diabetic model group （P 〈0.05）. AR activity as well as the expression of AR mRNA and protein in the kidney was markedly decreased in the berberine treatment group compared with diabetic model group （P 〈0.05）. Conclusion These results suggested that berberine could ameliorate renal dysfunction in DN rats through controlling blood glucose, reduction of oxidative stress and inhibition of the activation of the polyol pathway.
基金supported by a grant from the National Natural Science Foundation of China,No.81060141
文摘Epalrestat is a noncompetitive and reversible aldose reductase inhibitor used for the treatment of diabetic neuropathy. This study assumed that epalrestat had a protective effect on diabetic peripheral nerve injury by suppressing the expression of aldose reductase in peripheral nerves of diabetes mellitus rats. The high-fat and high-carbohydrate model rats were established by intraperitoneal injection of streptozotocin. Peripheral neuropathy occurred in these rats after sustaining high blood glucose for 8 weeks. At 12 weeks after streptozotocin injection, rats were intragastrically administered epalrestat 100 mg/kg daily for 6 weeks. Transmission electron microscope revealed that the injuries to myelinated nerve fibers, non-myelinated nerve fibers and Schwann cells of rat sciatic nerves had reduced compared to rats without epalrestat administuation. Western blot assay and immunohistochemical results demonstrated that after intervention with epalrestat, the activities of antioxidant enzymes such as superoxide dismutase, catalase and glutathione peroxidase gradually increased, but aldose reductase protein expression gradually diminished. Results confirmed that epalrestat could protect against diabetic peripheral neuropathy by relieving oxidative stress and suppressing the polyol pathway.
基金National Institutes of Health,Grant/Award Number:R01NS079792UNTHSC Seed Grants,Grant/Award Number:RI10015 and RI10039
文摘In diabetes mellitus, the polyol pathway is highly active and consumes approximately 30% glucose in the body. This pathway contains 2 reactions catalyzed by aldose reductase(AR) and sorbitol dehydrogenase, respectively. AR reduces glucose to sorbitol at the expense of NADPH, while sorbitol dehydrogenase converts sorbitol to fructose at the expense of NAD+, leading to NADH production. Consumption of NADPH, accumulation of sorbitol, and generation of fructose and NADH have all been implicated in the pathogenesis of diabetes and its complications. In this review, the roles of this pathway in NADH/NAD+redox imbalance stress and oxidative stress in diabetes are highlighted. A potential intervention using nicotinamide riboside to restore redox balance as an approach to fighting diabetes is also discussed.
