褪黑素抑制四氧嘧啶糖尿病大鼠垂体-肾上腺轴功能

观察褪黑素对以四氧嘧啶诱发大鼠糖尿病时垂体-肾上腺轴的影响。结果提示褪黑素对糖尿病模型大鼠的垂体-肾上腺轴有抑制作用，对急性代谢紊乱有保护作用。     

Proteolytic activity in the brain of alloxan diabetic rats: Presence of a proteolytic activator in the cerebral extract

BACKGROUND AND AIM:

Diabetes mellitus is known to cause neurological disorders due to impaired glucose metabolism involving decreased utilization of glucose by the brain tissues. The mechanisms responsible for failure of glycemic regulation in type-2 diabetes leading to neurological impairment need to be thoroughly elucidated.

MATERIALS AND METHODS:

Type-2 diabetes was induced in albino rat models with alloxan monohydrate (40 mg/kg i.v.). Cerebral cortex and medulla oblongata were investigated 48 h after alloxan administration for the alterations in proteolytic activity.

RESULTS:

Diabetes caused an elevation (P < 0.001) of blood glucose and also proteolytic activity in the brain.

CONCLUSION:

Impaired glucose metabolism in the brain was the key factor which was responsible for the elevated (P < 0.001) proteolysis leading to brain dysfunction.     

复方儿茶胶囊治疗消化性溃疡疗效观察

目的观察复方儿茶胶囊对消化性溃疡的近期和远期疗效。方法经胃镜确诊的消化性溃疡261例,随机分为西米替丁组87例(西米替丁0.2g,每天3次口服,睡前加服0.4g),丽珠得乐组87例(丽珠得乐110mg,每天4次口服),复方儿茶胶囊组87例(复方儿茶胶囊0.515g,每天3次口服)。治疗前、治疗8周后及1年后距幽门5cm以内取胃组织,用快速尿素酶法测定幽门螺杆菌(HP)。结果西米替丁组、丽珠得乐组、复方儿茶胶囊组总有效率分别为86.2％,88.5％．97.7％,复方儿茶胶囊组与前两组相比P＜0.05。溃疡愈合率分别为70.1％．75.9％,90.8％．复方儿茶胶囊组与前两组相比P＜0.05。HP根除率分别为1.9％,57.4％,76.8％,复方儿茶胶囊组与丽珠得乐组相比P＜0.05,与西米替丁组相比P＜0.01。结论复方儿茶胶囊组溃疡近期疗效及HP根除率均高于西米替丁组和丽珠得乐组,复发率均低于西米替丁组和丽珠得乐组。     

Antihyperglycemic activity, antihyperlipedemic activity, haematological effects and histopathological analysis of Sapindus mukorossi Gaerten fruits in streptozotocin induced diabetic rats

ObjectiveTo investigate the antihyperglycemic and antihyperlipidemic properties of hydroalcoholic extract of fruits of Sapindus mukorossi Gaerten and its beneficial effect on haematological parameters with histopathological analysis in streptozotocin induced diabetic rats.MethodsSapindus mukorossi fruits extract (250 and 500 mg/kg body weight) and standard drug glybenclamide (0.5 mg/kg body weight) were administered to diabetic rats. Effect of extract on hyperglycemia, hyperlipidemia and hematological parameters was studied in diabetic rats. Histopathological changes in diabetic rat pancreas were also observed after extract and glybenclamide treatment.ResultsDaily oral administration of Sapindus mukorossi fruits extract (250 and 500 mg/kg body weight) and glybenclamide for 20 days showed beneficial effects on blood glucose level (P<0.01) and lipid level. The extract has a favorable effect on the histopathological changes of the pancreas in streptozotocin induced diabetes.ConclusionThese findings reveal that the hydroalcoholic extract of Sapindus mukorossi fruits extract possesses antihyperglycemic and antihyperlipidemic properties. In addition, the extract can prevent various complications of diabetes and improve some haematological parameters.     

Effects of Gmelina arborea extract on experimentally induced diabetes

ObjectiveTo study the effects of aqueous extract of Gmelina arborea bark on normoglycemic levels and streptozotocin (STZ) induced diabetes in rats.MethodsAfter single administration of the aqueous extract, plasma glucose level was determined up to 6 h. In subacute study, the aqueous extract was administered for 28 d and plasma glucose level was determined weekly. The diabetes was induced in rats by the intraperitoneal injection of STZ at a dose of 55 mg/kg body weight. The diabetic animals were divided into four groups containing six in each: Group I diabetic control, Group II and III treated with the aqueous extract respectively at a dose of 250 and 500 mg/kg body weight once daily and Group IV treated with glibenclamide at a dose of 0.6 mg/kg body weight once daily. In acute study, the aqueous extract and glibenclamide were administered orally to rats. Plasma glucose levels were determined at 30, 60, 120, 240 and 360 min after the administration of the test samples. To study subacute effects, test samples (the aqueous extract and glibenclamide) were administered for 28 d consecutively. The effects of each test sample on plasma glucose level, body weight as well as food and water intake were also monitored weekly. The oral glucose tolerance test and biochemical indicators were estimated on day 28.ResultsThe aqueous extract did not significantly decrease the plasma glucose level in the normoglycemic rats as shown by the acute and subacute assays. However, after oral administration of the aqueous extract, the plasma glucose level was significantly (P<0.001) decreased in the diabetic rats in the acute study. The long-term administration of the aqueous extract significantly (P<0.001) reduced plasma glucose levels of the diabetic rats. Additionally, the aqueous extract also reduced loss of body weight and significantly decreased food and water intake in the diabetic animals. Nevertheless, no effects on biochemical indicators were observed at the selected doses.ConclusionsThe aqueous extract of Gmelina arborea bark had antihyperglycemic activity against STZ induced diabetes in rats, after single and subacute oral administration. Moreover, it did not show significant glucose lowering effect in normoglycemic rats.     

罗格列酮对四氧嘧啶介导的糖尿病家兔心室肌细胞L型钙通道电流的影响

目的探讨罗格列酮对家兔心室肌细胞L型钙通道电流(I_(CaL))的影响。方法四氧嘧啶建立糖尿病家兔模型后,利用酶解法急性分离心室肌细胞,用全细胞膜片钳技术观测糖尿病和罗格列酮对心肌细胞I_(CaL)的影响,并与正常家兔进行比较。结果 (1)正常组家兔心室肌细胞I_(CaL)电流密度[(-8.83±2.31)pA/pF]大于糖尿病组[(-8.84±1.98)pA/pF],但差异不具有统计学意义。(2)给予罗格列酮后正常和糖尿病家兔组心室肌细胞I_(CaL)[正常组:基线电流密度(-8.83±2.31 pA/pF)大于5 min电流密度(-4.17±1.89 pA/pF)和10 min电流密度(-5.54±1.63)pA/pF,糖尿病组:基线电流密度(-8.84±1.98)pA/pF大于5 ml‘n电流密度(-4.97±1.15)pA/pF和10 min电流密度(-3.89±1.06)pA/pF],各时段差异均有统计学意义(各组P<0.05)。(3)空腹血糖[(7.65±1.60)mmol/L]小于建模48 h[(17.72±9.15)mmol/L]及1周后空腹血糖[(20.84±9.48)mmol/L]。各时段胰岛素水平[空腹(23.45±9.22)mmol/L,48 h后(22.69±8.94)mmol/L,1周后(21.65±11.91)mmol/L]差异均无统计学意义(各组P>0.05)。结论正常家兔组I_(CaL)电流密度与糖尿病家兔组相似,提示糖尿病对心肌细胞I_(CaL)无明显影响;罗格列酮对心脏的作用不依赖于高血糖存在与否,提示罗格列酮可能通过某些与胰岛素水平有关的特定机制作用于心肌细胞;四氧嘧啶所致糖尿病模型是一种不完全等同于1型及2型糖尿病的独特模型,但去除了胰岛素抵抗的影响。该模型可以用来作为高血糖对心肌细胞离子通道影响的研究载体。     

Hypoglycemic activity of Hemidesmus indicus R. Br. on streptozotocin-induced diabetic rats

OBJECTIVE:

To evaluate the antidiabetic activity of an aqueous extract of the roots of Hemidesmus indicus on blood glucose, serum electrolytes, serum marker enzymes, liver microsomal P-450 enzymes, and lipid peroxidation in the liver and kidney of streptozotocin-induced diabetic rats.

MATERIALS AND METHODS:

Effect of H. indicus extract on blood glucose was studied with fed, fasted and glucose-loaded diabetic and nondiabetic rat models. The effect of the extract on serum electrolytes, serum levels of key glucose metabolizing enzymes, hepatic microsomal protein and hepatic cytochrome P-450-dependent mono-oxygenase enzyme systems and lipid peroxidation in the liver and kidney of diabetic rats. One way analysis of variance and Duncan''s multiple range test was used for statistical analysis.

RESULTS:

Oral administration of H. indicus aqueous extract to fed, fasted and glucose-loaded diabetic rats decreased blood glucose level significantly at 5 h and restored serum electrolytes, glycolytic enzymes and hepatic cytochrome P-450-dependent enzyme systems by preventing the formation of liver and kidney lipid peroxides at the end of 12 weeks of the study period.

CONCLUSION:

From the studies, it can be concluded that the aqueous extract of the roots of H. indicus at a dosage of 500 mg/kg/day exhibits significant antidiabetic activity. It restores the concentrations of electrolytes, glucose metabolizing enzymes, hepatic microsomal protein and hepatic cytochrome P-450-dependent mono-oxygenase enzyme systems to near normal level and also corrects the related metabolic alterations in experimentally induced diabetic rats. H. indicus administration also decreased liver and kidney lipid peroxidation products. On the basis of our findings, H. indicus could be used as an antidiabetic and antioxidant agent for the prevention and treatment of diabetes mellitus.     

Antihyperglycemic effects of stevioside in type 2 diabetic subjects

Stevioside is present in the plant Stevia rebaudiana Bertoni (SrB). Extracts of SrB have been used for the treatment of diabetes in, for example, Brazil, although a positive effect on glucose metabolism has not been unequivocally demonstrated. We studied the acute effects of stevioside in type 2 diabetic patients. We hypothesize that supplementation with stevioside to a test meal causes a reduction in postprandial blood glucose. Twelve type 2 diabetic patients were included in an acute, paired cross-over study. A standard test meal was supplemented with either 1 g of stevioside or 1 g of maize starch (control). Blood samples were drawn at 30 minutes before and for 240 minutes after ingestion of the test meal. Compared to control, stevioside reduced the incremental area under the glucose response curve by 18% (P =.013). The insulinogenic index (AUC(i,insulin)/AUC(i,glucose)) was increased by approximately 40% by stevioside compared to control (P <.001). Stevioside tended to decrease glucagon levels, while it did not significantly alter the area under the insulin, glucagon-like peptide 1, and glucose-dependent insulinotropic polypeptide curves. In conclusion, stevioside reduces postprandial blood glucose levels in type 2 diabetic patients, indicating beneficial effects on the glucose metabolism. Stevioside may be advantageous in the treatment of type 2 diabetes.     

槟榔杀灭钉螺的效果观察

目的观察槟榔提取物杀灭钉螺的效果。方法采用室内浸杀法,对槟榔乙醇提取物的杀螺效果及抑制钉螺上爬情况进行观察。结果槟榔乙醇提取物浸泡钉螺24、48h和72h的LC50分别为60.9、26.9mg/L和16.3mg/L。浸泡24h时,12.5mg/L浓度明显抑制钉螺上爬,而25.0mg/L的上爬率为0。结论槟榔乙醇提取物具有较好的杀灭钉螺效果和抑制钉螺上爬作用,是一种有研究价值的植物杀螺剂。     

Cancer biology in diabetes

Diabetes is a serious metabolic disease that causes multiple organ dysfunctions. Recent evidence suggests that diabetes could contribute to the initiation and progression of certain cancers in addition to the classic diabetic complications. Furthermore, some of the drugs used clinically to treat patients with diabetes might affect cancer initiation, progression and mortality. The recent discovery of the possible anticancer effects of metformin, a classic antidiabetic drug, has led physicians and scientists to reconsider the interaction between diabetes and cancer. In the present review, we analyze recent reports in this field, and explore possible mechanistic links between diabetes and cancer biology.     

Antidiabetic activity of aqueous leaf extract of Atriplex halimus L. (Chenopodiaceae) in streptozotocin-induced diabetic rats

Objective

To investigate the antidiabetic effect of A. halimus leaf in streptozotocin-induced diabetic rats.

Methods

The aqueous extract of the plant leaf was tested for its efficacy in streptozotocin-induced diabetic rats. The extract was evaluated for its acute and short term general toxicity in male mice and for its antihyperglycemic activity using glucose tolerance test in rats. The aqueous extract was subjected to phytochemical screening and determination of total phenolic contents.

Results

The statistical data indicated the significant increase in the body weight and decrease in the blood glucose and hepatic levels. The total protein level was significantly increased when treated with the extract.

Conclusions

These results suggest that the aqueous leaf extract of A. halimus has beneficial effects in reducing the elevated blood glucose level and hepatic levels in streptozotocin-induced diabetic rats.     

Sodium-Glucose Co-Transporter 2 Inhibitors and the Risk of Venous Thromboembolism in Patients with Type 2 Diabetes: A Cohort Study

PurposeWe assessed whether sodium-glucose co-transporter type 2 (SGLT2) inhibitors are associated with a higher incidence rate of venous thromboembolism in patients with type 2 diabetes.MethodsWe conducted a population-based cohort study using the InGef database including patients with type 2 diabetes newly treated with noninsulin antidiabetic drugs between 2012 and 2018. Cases of venous thromboembolism identified during follow-up were matched to 40 controls on age, sex, cohort entry date, and duration of follow-up. Using a nested case-control approach, conditional logistic regression estimated incidence rate ratios (RRs) with 95% confidence intervals (CIs) of venous thromboembolism adjusted for sociodemographic and clinical variables, comparing current use of SGLT2 inhibitors with current use of dipeptidyl peptidase-4 (DPP-4) inhibitors.ResultsIn a cohort of 219,538 patients, we identified 2152 cases of venous thromboembolism and matched them to 85,104 controls. Compared with DPP-4 inhibitors, current use of SGLT2 inhibitors was associated with a lower rate of venous thromboembolism (RR, 0.75; 95% CI, 0.59-0.94). Effect estimates were similar for dapagliflozin (RR, 0.77; 95% CI, 0.57-1.03) and empagliflozin (RR, 0.71; 95% CI, 0.52-0.98).ConclusionsCompared with DPP-4 inhibitors, SGLT2 inhibitors were not associated with a higher rate of venous thromboembolism, providing reassurance regarding their thromboembolic safety.     

Foraging ability of rufous hummingbirds on hummingbird flowers and hawkmoth flowers

We examine the suitability of ornithophilous flowers and sphingophilous flowers in Ipompsis and Aquilegia for nectar foraging by the hummingbird Selasphorus rufus. In S. rufus, bill length averages 18.9 mm in females and 17.3 mm in males. Maximal tongue extension approximates bill length, suggesting that birds can feed from floral tubes up to 33.5 mm in length. However, their ability to do so is limited by two factors. First, the maximal depth at which S. rufus can extract nectar decreases with the width of the floral tube. Second, feeding time is shortest in short floral tubes and progressively increases as the tubes lengthen because of increased time required for tongue extension and retraction. Hence, nectar foraging occurs with optimal efficiency in moderately broad floral tubes with lengths that do not exceed or only slightly exceed the bill length plus 相似文献   

普罗布考对糖尿病肾病大鼠氧化应激的影响

目的 观察普罗布考(PB)对糖尿病肾病(DN)大鼠氧化应激的影响.方法 60只Sprague-Dawley (SD)雄性大鼠随机分成4组:正常对照组(NC组)8只,右肾血管结扎组(RL组)8只,DN组22只,DN+ PB组22只.RL组、DN组和DN+ PB组首先进行右肾血管结扎,1周后DN组和DN+ PB组应用50 ...     

Blood levels of alloxan in children with insulin-dependent diabetes mellitus

Alloxan is a well-known and universally used agent for evoking experimental diabetes through its toxic effect on the B cells of the Langerhans islets. In our study, blood levels of alloxan in children with insulin-dependent diabetes mellitus were investigated. The observations were made in 68 children aged 6–15 years and in a control group of 44 healthy children in the same age range. Alloxan levels were estimated spectrophotometrically. The mean level of alloxan in blood from children with insulin-dependent diabetes mellitus was 8.76±9.64 g/ml and in blood from healthy children was 1.53±1.10 g/ml. The difference was statistically significant (P<0.05). The metabolism of alloxan leads to the production of free superoxide radicals which, as is well known, injure cells and cause conditions conducive to the occurrence of diseases from autoimmunity. The results obtained suggest therefore that higher levels of alloxan in diabetic children are of significance in the onset of insulin-dependent diabetes mellitus.     

Repurposing metformin for the treatment of gastrointestinal cancer

Diabetes mellitus type 2 and cancer share many risk factors. The pleiotropic insulin-dependent and insulin-independent effects of metformin might inhibit pathways that are frequently amplified in neoplastic tissue. Particularly, modulation of inflammation, metabolism, and cell cycle arrest are potential therapeutic cancer targets utilized by metformin to boost the anti-cancer effects of chemotherapy. Studies in vitro and in vivo models have demonstrated the potential of metformin as a chemo- and radiosensitizer, besides its chemopreventive and direct therapeutic activity in digestive system (DS) tumors. Hence, these aspects have been considered in many cancer clinical trials. Case-control and cohort studies and associated meta-analyses have evaluated DS cancer risk and metformin usage, especially in colorectal cancer, pancreatic cancer, and hepatocellular carcinoma. Most clinical studies have demonstrated the protective role of metformin in the risk for DS cancers and survival rates. On the other hand, the ability of metformin to enhance the actions of chemotherapy for gastric and biliary cancers is yet to be investigated. This article reviews the current findings on the anti-cancer mechanisms of metformin and its apparatus from pre-clinical and ongoing studies in DS malignancies.     

Evaluation of traditional plant treatments for diabetes: Studies in streptozotocin diabetic mice

Summary Seven plants and a herbal mixture used for traditional treatment of diabetes were studied in streptozotocin diabetic mice. The treatments were supplied as 6.25% by weight of the diet for 9 days. Consumption of diets containing bearberry (Arctostaphylos uva-ursi), golden seal (Hydrastis canadensis), mistletoe (Viscum album) and tarragon (Artemisia dracunculus) significantly reduced the hyperphagia and polydipsia associated with streptozotocin diabetes, but bayberry (Cinnamomum tamala), meadowsweeet (Filipendula ulmaria), senna (Cassia occidentalis) and the herbal mixture did not alter these parameters. Bearberry, mistletoe and tarragon retarded the body weight loss but none of the eight treatments significantly altered plasma glucose or insulin concentrations. These studies suggest that bearberry, golden seal, mistletoe and tarragon may counter some of the symptoms of streptozotocin diabetes without, however, affecting glycemic control.