Effect of Mucuna pruriens (Linn.) on mitochondrial dysfunction and DNA damage in epididymal sperm of streptozotocin induced diabetic rat

Ethnopharmacological relevance

Mucuna pruriens Linn. (M. pruriens) is a leguminous plant that has been recognized as an herbal medicine for improving fertility and related disorders in the Indian traditional system of medicine, however without proper scientific validations.

Aim of the study

To study the effect of ethanolic seed extract of M. pruriens on mitochondrial dysfunction and the DNA damage in hyperglycemic rat epididymal spermatozoa.

Materials and methods

Male Wistar albino rats were divided as control (Sham), diabetes induced [streptozotocin 60 mg/kg of body weight (b.w.) in 0.1 M citrate buffer] (STZ), diabetic rats administered with 200 mg/kg b.w. of extract (STZ+MP) and normal rats administered with 200 mg/kg b.w. of extract (Sham+MP). M. pruriens was administered (gavage) once daily for a period of 60 days. On 60th day animals were sacrificed by cervical dislocation sperm were collected from epididymis and subjected various analysis like antioxidants, ROS, lipid peroxidation (LPO), DNA damage, chromosomal integrity and mitochondrial membrane potential (MMP).

Results

Significant reduction in the sperm count, motility, viability and significant increase in the number of abnormal sperm in STZ compared to sham was noticed. STZ rat sperm showed significant increase in LPO and DNA damage. Both the enzymic and non-enzymic were decreased; MMP and the mitochondrial functions were severely affected in STZ group. The diabetic rats supplemented with M. pruriens showed a remarkable recovery in antioxidant levels and reduced LPO with well preserved sperm DNA. MMP and mitochondrial function test were also preserved in STZ+MP rat sperm.

Conclusion

The present study has clearly demonstrated the potency of M. pruriens to reduce the diabetic induced sperm damage induced by oxidative stress (OS). These observations are encouraging to perform similar studies in human.     

Antidiabetic effect of Symplocos cochinchinensis (Lour.) S. Moore. in type 2 diabetic rats

Aim

Symplocos cochinchinensis (Lour.) S. Moore. is used in Indian system of traditional medicine to treat diabetes mellitus. The present study aims to investigate the antidiabetic efficacy of the hexane extract of Symplocos cochinchinensis leaves in high fat diet-low streptozotocin (STZ) induced type 2 diabetic rats.

Materials and methods

The doses for the study were fixed based on Irwin test. The hypoglycemic effect of the hexane extract of Symplocos cochinchinensis leaves were studied in normal rats. Oral glucose and insulin tolerance tests were carried out. The antihyperglycemic effect of the hexane extract at 250 and 500 mg/kg was studied in high fat diet-low STZ induced type 2 diabetic rats for 28 days.

Results

The extracts showed no adverse effects up to 5 g/kg concentration. In hypoglycemic study, after treatment with hexane extract at 250 and 500 mg/kg the blood glucose was mildly reduced. In oral glucose tolerance test, the treatment with the hexane extract at 250 and 500 mg/kg showed a highly significant reduction of 12.07% and 23.58% in plasma glucose levels, respectively 30 min after glucose load. The insulin tolerance test also showed improved insulin sensitivity after 60 min of insulin treatment. In high fat diet-low STZ induced type 2 diabetic rats, after 28 days treatment with the hexane extract at 250 and 500 mg/kg reduced the plasma glucose level by 17.04% and 42.10%, respectively. A significant reduction in plasma insulin, plasma and hepatic total cholesterol (TC), triglycerides (TG) and free fatty acids (FFA) and a significant increase in liver glycogen were observed in treated diabetic rats.

Conclusion

This study demonstrated the potential antidiabetic property of hexane extract of Symplocos cochinchinensis leaves on type 2 diabetes mellitus, thus justifying its traditional usage.     

Evaluation of antidiabetic and antihyperlipidemic activity of Artemisia indica linn (aeriel parts) in Streptozotocin induced diabetic rats

Ethnopharmacological relevance

Diabetes mellitus is a major metabolic disorder affecting a huge population all over the world. Artemisia species have been extensively used for the management of diabetes in folkloric medicine. The present study is designed to investigate the antidiabetic and antihyperlipidemic effects of aeriel parts of Artemisia indica.

Materials and methods

Hydromethanolic crude extracts, chloroform, ethyl acetate and n-butanol fractions of aerial parts of Artemisia indica were tested for their antidiabetic potential in Streptozotocin (STZ) (50 mg/kg, i.p.) induced diabetic Sprague-Dawley rats. Blood glucose level, body weight, serum lipid profile and activities of liver enzymes were determined. The extracts were further subjected to preliminary phytochemical analysis.

Results

A daily oral dose of hydromethanolic crude extracts (200 and 400 mg/kg b.w.) and chloroform fraction (200 mg/kg b.w.) of Artemisia indica for 15 days showed a significant reduction in blood glucose level which was comparable to that of the standard antidiabetic drug, glibenclamide (500 μg/kg, p.o.). Artemisia indica extracts also showed reduction in total cholesterol, triglycerides and low density lipoproteins as well as serum creatinine level, serum glutamate pyruvate transaminase (SGPT), serum glutamate oxaloacetate transaminase (SGOT) and alkaline phosphatase (ALP) in diabetic rats.

Conclusion

According to the results Artemisia indica possesses hypoglycemic, antihyperlipidemic and valuable effects on liver and renal functions in diabetic rats, which seems to validate its traditional usage.     

Antidiabetic effect of Ficus religiosa extract in streptozotocin-induced diabetic rats

Aims of study

In Indian traditional system of medicine, Ficus religiosa (Family Moraceae) is prescribed for the treatment of diabetes mellitus. In the present study, the antidiabetic effect of aqueous extract of Ficus religiosa bark (FRAE) was investigated in normal, glucose-loaded hyperglycemic and streptozotocin (STZ)-induced diabetic rats.

Materials and methods

Oral administration of FRAE at the doses of 25, 50 and 100 mg/kg was studied in normal, glucose-loaded and STZ-diabetic rats.

Results

The three doses caused significant reduction in blood glucose levels in all the models. The effect was more pronounced in 50 and 100 mg/kg than 25 mg/kg. FRAE also showed significant increase in serum insulin, body weight and glycogen content in liver and skeletal muscle of STZ-induced diabetic rats while there was significant reduction in the levels of serum triglyceride and total cholesterol. FRAE also showed significant antilipidperoxidative effect in the pancreas of STZ-induced diabetic rats. The antidiabetic effect of Ficus religiosa was compared with glibenclamide, a well-known hypoglycemic drug.

Conclusion

The results indicate that aqueous extract of Ficus religiosa bark possesses significant antidiabetic activity.     

灵芝多糖联合二甲双胍对糖尿病大鼠胸主动脉晚期糖基化终末产物与结缔组织生长因子的干预作用

目的 观察灵芝多糖和二甲双胍联用对糖尿病大鼠胸主动脉晚期糖基化终末产物(AGEs)和结缔组织生长因子(CTGF)表达的影响。方法 SD大鼠采用高能量饮食4周加ip小剂量链脲佐菌素(STZ)30 mg/kg建立2型糖尿病模型。成模后随机分为模型组、灵芝多糖(600 mg/kg)组、二甲双胍(600 mg/kg)组及联合用药组(灵芝多糖300 mg/kg+二甲双胍300 mg/kg),另设对照组。给药治疗12周末测定大鼠空腹血糖、血浆胰岛素、血清AGEs;测定血清过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)活性;电镜超微结构观察胸主动脉病理改变;免疫组化和蛋白印记法检测胸主动脉AGEs及CTGF蛋白的表达。结果 联合用药组能显著降低糖尿病大鼠空腹血糖,升高血浆胰岛素水平,降低血清AGEs的量及升高血清CAT、GSH-Px活性,减少胸主动脉AGEs及CTGF的表达,减轻胸主动脉病变过程。结论 灵芝多糖联合二甲双胍可能通过抑制主动脉氧化应激、降低血清AGEs水平以及下调主动脉AGEs、CTGF的表达,从而对糖尿病大鼠主动脉起到保护作用。     

Antihyperglycemic effects of total flavonoids from Polygonatum odoratum in STZ and alloxan-induced diabetic rats

Aim of the study

Total flavonids of Polygonatum(P) odoratum (TFP) were tested for anti-diabetic activity in streptozotocin (STZ)-induced diabetic mice and alloxan-induced diabetic rats.

Materials and methods

Rhizoma Polygonati Odorati, well-known Chinese traditional medicine, is widely used for treatment of diverse diseases for example diabetes. In our study, TFP was extracted by 70% ethanol and purified by macroreticular resin. The experiments were designed to detect the anti-diabetic activity of TFP by determination of blood glucose (BG) using one touch gluco-meter and insulin levels by using a radioimmunoassay kit in streptozotocin (STZ)-induced diabetic mice and alloxan-induced diabetic rats and alpha-amylase inhibitory activity by alpha-amylase inhibition assay in vitro.

Results

TFP had beneficial effects on regulation of blood glucose. Daily administration with 50–200 mg/kg body weight of TFP for 9 days can reduce significantly hyperglycemia in STZ-induced diabetic mice. Thirtieth day administration with TFP (50–200 mg/kg body weight) also decreased significantly fasting blood glucose in alloxan-induced diabetic rats. The hypoglycemic effect of TFP at 50 and 100 mg/kg is less than that of acarbose 20 mg/kg and gliclazide 15 mg/kg. The hypoglycemic effects of TFP at 200 mg/kg is similar to that of acarbose 20 mg/kg and gliclazide 15 mg/kg. TFP also could increase significantly the insulin level in alloxan-induced type 2 diabetic rats (P < 0.05) compared with control. Alpha-amylase inhibition assay in vitro showed that TFP inhibited significantly alpha-amylase activity in a dose-dependent manner.

Conclusions

TFP possess significant dose-dependent anti-diabetic activity. TFP is one of the primary hypoglycemic active compounds of Polygonatum odoratum which would worth further study and development.     

Hypoglycaemic effects of Mammea africana (Guttiferae) in diabetic rats

Aim of the study

The stem bark of Mammea africana Sabine (Guttiferae) is used in African rain forest to treat various diseases, including diabetes mellitus. We investigated whether Mammea africana extract induced hypoglycaemic activity in rats.

Materials and methods

We tested the effects of acute (5 h) and sub-acute (21 days) oral administrations of the CH₂Cl₂–MeOH stem bark extract of Mammea africana (19–300 mg/kg body weight) on blood glucose levels of normal and streptozotocin (STZ)-induced type 1 diabetic rats. The effects were compared with those of glibenclamide.

Results

Acute administration reduced blood glucose in the diabetic rats only (33.87%, P < 0.01). Sub-acute treatment for 21 days also reduced blood glucose level in diabetic rats (73.29%, P < 0.01). A reduction or stabilization in total serum protein, triglyceride, cholesterol and alanine amino transferase levels was also observed. No effect was observed on body weight loss but food and water intakes were significantly reduced (P < 0.01) in diabetic rats. The maximal anti-diabetic effect was obtained with the dose of 75 mg/kg and was more important than that of glibenclamide.

Conclusion

It can be concluded that extracts of Mammea africana exhibited a significant anti-hyperglycaemic activity and improved the metabolic alterations in STZ-diabetic rats. These results provide a rationale for the use of Mammea africana to treat diabetes mellitus and hypercholesterolemia.     

Effect of tetramethylpyrazine on lipid peroxidation in streptozotocin-induced diabetic mice

Oxygen free radicals have been suggested to be a contributory factor in complications of diabetes mellitus. In the present study, we investigated the effect of tetramethylpyrazine (TMP) (10, 25 and 50 mg/kg), an active component of a Chinese medicinal plant Ligusticum wallich Franch (chuanxiang), on streptozotocin (STZ)-induced diabetic male ICR mice. STZ was injected as a single daily dose (4 mg/kg i.p. in buffered citrate solution, pH 4.0) for one week. A single daily dose of TMP (10, 25 or 50 mg/kg i.p.) was administered for 2 weeks to the STZ-induced diabetic mice immediately following 1 week STZ induction. Plasma glucose and serum blood urea nitrogen (BUN) concentrations were estimated at the time of sacrifice. Malonialdehyde (MDA) formation was measured from the liver and kidney tissues. TMP dose dependently inhibited glucose concentration and BUN elevation. TMP also remarkably reduced the degree of lipoperoxidation. Our results indicate that TMP may be an effective agent for treatment of diabetes mellitus complications with oxidative stress.     

Hypoglycemic effects of malonyl‐ginsenosides extracted from roots of Panax ginseng on streptozotocin‐induced diabetic mice

Hypoglycemic effects of malonyl‐ginsenosides (MGR), extracted from roots of Panax ginseng, were examined in streptozotocin‐ (STZ‐) induced diabetic mice. Animals received daily intravenous injections of MGR in doses of 30, 60, 120 mg/kg. At a dose of 120 mg/kg, MGR reduced the fasting blood glucose level of diabetic mice by 77.8% (76.7 ± 8.5 mg/dl versus 345.2 ± 35.8 mg/dl, P < 0.01). The same dose also showed a marked improvement in glucose tolerance of 80% (75.3 ± 10.8 mg/dl versus 375.6 ± 43.3 mg/dl, P < 0.01) in diabetic mice after four days. The alkali hydrolysis productions of MGR, ginseng panaxadiol (PDS), malonic acid and a mixture of malonic acid with PDS, showed no effects on fasting blood glucose levels indicated the hypoglycemic effect of MGR relied on their unique esterified chemical structures. The findings from this study suggest that MGR extracted from Panax ginseng may be prescribed as adjunct to drug treatment for controlling diabetes mellitus. Copyright © 2009 John Wiley & Sons, Ltd.     

Pharmacological characterization of different fractions of Calotropis procera (Asclepiadaceae) in streptozotocin induced experimental model of diabetic neuropathy

Ethnopharmacological relevance

Calotropis procera (Ait.) R.Br. is one of an ancient traditional shrub, which has been used for the treatment of diabetes, pain and inflammation for thousands of years in India. The root extract of Calotropis procera has been widely used by the tribal?s of district Udaipur, Rajasthan (India) for treatment of diabetes mellitus and its associated complications like diabetic neuropathy. The present study was performed to explore the protective effect of root, stem and leaf extracts of Calotropis procera in diabetes and diabetic neuropathy against tactile allodynia, mechanical hyperalgesia and thermal hyperalgesia in streptozotocin induced diabetic rats.

Materials and methods

Diabetes and peripheral neuropathy were induced in Wistar rats by injection of streptozotocin (45 mg/kg/intraperitoneally). The roots, stem and leaves of Calotropis procera were sequentially extracted with petroleum ether, chloroform, ethyl acetate and methanol. All the extracts were assessed by oral administration at 100 and 250 mg/kg in streptozotocin diabetic rats. The following compounds were used as positive controls: insulin NPH (1 IU/kg/day), metformin (500 mg/kg/day), glibenclamide (2.5 mg/kg/day) and a combination of acarbose (20 mg/kg/day) with methylcobalamine (500 µg/kg/day). In contrast, the streptozotocin induced untreated diabetic rats termed as negative control. Thermal hyperalgesia, mechanical hyperalgesia and tactile allodynia were evaluated in all groups of streptozotocin diabetic rats to assess the extent of neuropathy by Eddy?s hot plate, tail immersion, Randall–Selitto and Von Frey hair tests. The basal nociceptive thresholds were assessed in week 4 of post streptozotocin injection. All groups received their treatment on a regular basis from 28 to 42 days following a confirmation of diabetic neuropathy. The nociceptive thresholds were assessed in all groups in week 5 and 6. The histopathology of pancreas and biochemical estimations of plasma insulin and glycosylated haemoglobin (HbA₁C%) levels were also performed in week 6 of post streptozotocin injection.

Results

The negative control rats developed diabetes and diabetic neuropathy after 6 week of streptozotocin administration distinguished by significant (p<0.01) hyperalgesia and tactile allodynia with enhanced HbA₁C% level compared to normoglycemic rats. Chronic administration of root methanol, stem methanol and leaf ethyl-acetate extracts of Calotropis procera for 2 weeks at 100 and 250 mg/kg doses significantly (p<0.01) attenuated the diabetes induced mechanical hyperalgesia, thermal hyperalgesia, tactile allodynia and HbA₁C% level in streptozotocin diabetic rats as compared to negative control rats. Further, the root methanol extract of Calotropis procera in 100 mg/kg dose showed the regeneration capability of β cells in the histology of pancreas with significant (p<0.01) improvement in plasma insulin level in streptozotocin diabetic rats compared to negative control rats.

Conclusion

Root methanol extract of Calotropis procera (100 mg/kg) has shown ameliorative effect in diabetic neuropathy which may be attributed by its multiple actions including potent hypoglycemic and antioxidant.     

Effects of Artemisia pallens Wall. on blood glucose levels in normal and alloxan-induced diabetic rats

Oral administration of the methanol extract of the aerial parts of Artemisia pallens Wall. (used in Indian folk medicine for the treatment of diabetes mellitus) led to significant blood glucose lowering effect in glucose-fed hyperglycaemic and alloxan-induced diabetic rats. This effect of the extract was dose dependent and significant at 100 mg/kg level in glucose-fed rats. In fasted normal rats, the extract caused a moderate hypoglycaemic effect at a higher dose (1000 mg/kg). The water extract (1000 mg/kg) was inactive.     

黄连地黄汤对糖尿病性心肌病大鼠心肌CTGF及FN1表达的影响

[目的] 研究黄连地黄汤对糖尿病性心肌病的防治作用。[方法] 80只SPF级SD大鼠分为空白对照组、模型组、黄连地黄汤低剂量组（2.7 g/kg生药）、黄连地黄汤中剂量组（5.4 g/kg生药）、黄连地黄汤高剂量组（10.8 g/kg生药）、二甲双胍（90 mg/kg）合并苯那普利（0.9 mg/kg）对照组。除空白对照组外其余大鼠先用高脂高糖饲料喂养6周，然后各组造模大鼠腹腔注射浓度为44 mg/kg的链脲佐菌素（STZ）。3 d后检测空腹血糖，选择血糖大于11.1 mmol/L的2型糖尿病模型。血糖符合标准的大鼠继续边喂饲高脂饲料边给药12周。末次给药1 h后测空腹血糖，然后各组大鼠用5%水合氯醛（6 mL/kg）麻醉，腹主动脉取血，检测血清低密度脂蛋白胆固醇（LDL-C）、总胆固醇（TC）、超氧化物歧化酶（SOD）、丙二醛（MDA），取心脏用福尔马林溶液固定，用于苏木精-伊红（HE）染色及免疫组化检测心肌细胞结缔组织生长因子（CTGF）和纤维连接蛋白抗体（FN1）表达。[结果] 研究结果表明黄连地黄汤可降低糖尿病性心肌病模型大鼠空腹血糖值、LDL-C、TC含量及心肌细胞结缔组织生长因子的表达，增加其抗氧化能力及纤维连接蛋白的表达。[结论] 黄连地黄汤对糖尿病性心肌病模型大鼠心肌细胞具有保护作用。     

Anti-hyperglycemic effect,inhibition of inflammatory cytokines expression,and histopathology profile in streptozotocin-induced diabetic rats treated with Arracacia tolucensis aerial-parts extracts

Ethopharmacological relevance

Arracacia tolucensis is a medicinal plant used in northeast of Mexico as a remedy to treat people with Diabetes mellitus (DM); however, there are no scientific studies that support this information. Thus, we evaluated the anti-hyperglycemic effect of the hexane, ethyl acetate and ethanol extracts from aerial parts in streptozotocin-induced diabetic rats.

Materials and methods

DM was induced in Wistar male rats by single intraperitoneal injection of streptozotocin (STZ 50 mg/kg). After STZ-induction, hyperglycemic rats were treated with all three extracts orally at a single dose (250 mg/kg) each 48 h for 21 days. Glibenclamide (1 mg/kg) was used as a reference drug. The fasting blood glucose levels, the hematic biometry and biochemical profiles, and the inhibition of inflammatory cytokines expression were estimated. Histopathology analysis of pancreas, liver, spleen, and kidney tissue was carried out.

Results

Ours results showed that ethyl acetate extract decreased blood glucose levels significantly (75%, p< 0.05) when compared to diabetic rats and controlled the body weight loss; the lipids level did not change, but the enzyme levels of aspartate aminotransferase and alanine aminotransferase decreased significantly (60.83% and 66.16%, respectively, p< 0.05) and inhibited the expression of inflammatory cytokines,with respect to diabetic rats. Histopathology injury was not observed; by contrast repair of islet of Langerhans was exhibited.

Conclusion

These results validate the use of Arracacia tolucensis as a treatment against DM and suggests it is suitable to continue studies for its safe therapeutic use.     

Antidiabetic effect of flavonoids from Malus toringoides (Rehd.) Hughes leaves in diabetic mice and rats

Ethnopharmacological relevance

The leaf of Malus toringoides (Rehd.) Hughes is a traditional folk medicine in Tibet, China, which is called “E Se” in Tibetan language. This original plant grows on snow mountains at an attitude of 3000 to 3700 m. It is primarily used to treat hypertension, hyperlipidemia, hyperglycemia, indigestion and other diseases. This study aimed to evaluate the antidiabetic effect of flavonoids extracted from E Se (ESF) and to explore the potential mechanism in streptozotocin (STZ) or alloxan (ALX) induced diabetic mice and STZ-induced diabetic rats.

Materials and methods

72 h after the establishment of a diabetic model, STZ or ALX induced diabetic mice and STZ-induced diabetic rats were treated daily with ESF at doses of 45, 90, 180 mg/kg and 37.5, 75, 150 mg/kg, respectively. Both mice and rats were fasted for 5 h before administration and the blood glucose (BG) levels were tested 1 h after treatment. Body weight was determined every other day. For STZ-induced rats, glycosylated hemoglobin (Hb1Ac), serum insulin and c-peptide, hepatic glycogen, superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels in liver were assessed on the fourth day after BG level detection.

Results

Compared with the model group, the general behavior of mice treated with ESF (90, 180 mg/kg) and rats treated with ESF (75, 150 mg/kg) became better and BG levels were significantly reduced (P<0.05). Significant decrease (P<0.05) in Hb1Ac level was observed in ESF-treated rats compared with diabetic rats. Significant increase (P<0.05 ) in serum insulin and c-peptide were detected in ESF-treated rats. The treatment also significantly (P<0.05) elevated SOD activity and reduced MDA level in the liver of diabetic rats. Besides, ESF 150 mg/kg had a trend of rising hepatic glycogen content of diabetic rats.

Conclusions

The findings of this study suggest that flavonoids from the Malus toringoides (Rehd.) Hughes leaves may possess an antidiabetic activity in animals with established diabetes.     

Effects of Citrullus colocynthis L. in a rat model of diabetic neuropathy

ObjectiveThis study investigated the biochemical, histopathological and physiological effects of Citrullus colocynthis on peripheral neuropathy in rats with streptozotocin (STZ)-induced diabetes.MethodsSeventy adult male Sprague-Dawley rats were included in the present study. Diabetes was induced in 60 rats, with a single intraperitoneal injection of STZ (65 mg/kg). After 4 weeks, the diabetic rats were assessed for neuropathy. Then, the diabetic rats with neuropathy were randomly divided into 6 groups for a 4-week treatment with gabapentin, oral administration of C. colocynthis fruit pulp powder (100 and 300 mg/kg per day), topical preparations as oil-based solution and ointment, or placebo. Changes in metabolic, physiological, biochemical and histological parameters were considered as treatment outcomes.ResultsMetabolic outcomes (body weight and blood glucose level) were improved in the C. colocynthis-treated groups as compared to placebo. Tail-flick and hot-plate tests also had lower latency in the C. colocynthis-treated groups. Measurement of oxidative stress markers (malondialdehyde, superoxide dismutase and catalase) showed the antioxidant effect of C. colocynthis. Histological evaluation of the sciatic nerve showed that C. colocynthis decreased the number of demyelinated and degenerated nerve fibers. Among the C. colocynthis-treated groups, the one receiving 100 mg/kg power per day orally had the best treatment outcomes.ConclusionThe present study showed that C. colocynthis fruit, through its antioxidant and hypoglycemic activities, has a positive effect in the treatment of diabetic neuropathy.     

斜生褐孔菌菌质对链脲佐菌素诱导的2型糖尿病大鼠的影响

目的 研究人工发酵的斜生褐孔菌菌质对链脲佐菌素(STZ)致2型糖尿病大鼠的影响,并与野生斜生褐孔菌菌核进行比较.方法 高糖、高脂饲料饲养SD大鼠6周,单次ip给予STZ 35 mg/kg制备2型糖尿病模型.将模型大鼠随机分成模型组、斜生褐孔菌菌质(菌质)1 g/kg组、野生斜生褐孔菌菌核(菌核)1 g/kg组和盐酸二甲双胍(0.2 g/kg)阳性对照组.连续ig给药10周后,检测各组大鼠体质量以及空腹血糖、胰岛素、糖化血红蛋白(HbA1c)、血清游离脂肪酸(FFA)、总胆固醇(TC)、三酰甘油(TG)、高密度脂蛋白-胆固醇(HDL-C)、低密度脂蛋白-胆固醇(LDL-C)、超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽过氧化物酶(GSH-Px)等水平,并进行口服葡萄糖耐量实验(OGTT).结果 给药10周后,与模型组比较,菌质组和菌核组大鼠的体质量明显增加(P＜0.05),血糖明显降低(P＜0.05),血清FFA、TC、TG和MDA水平下降(P＜0.05),SOD、GSH-Px水平升高(P＜0.05);菌质组与菌核组的上述指标无显著差异.结论 斜生褐孔菌菌质能缓解STZ致2型糖尿病大鼠症状,具有降低血糖、调节血脂、改善氧化应激的作用,且作用强度与野生斜生褐孔菌菌核相当.     

Antihyperglycemic and hypolipidemic activity of aqueous extract of Cassia auriculata L. leaves in experimental diabetes

Ethnopharmacological relevance

Cassia auriculata L. (Caesalpiniaceae) is widely used from ancient period to treat diabetes mellitus. The leaves of Cassia auriculata are having potential in the development of drug for diabetes due to its antihyperglycemic and lipid-lowering activity.

Aim of the study

The present study was to evaluate antihyperglycemic and hypolipidemic activity of aqueous extract of Cassia auriculata leaves (CLEt) in streptozotocin (STZ)-induced mild diabetic (MD) and severe diabetic (SD) rats.

Materials and methods

Male Albino rats were rendered diabetic by STZ (45 mg/kg, intraperitoneally). CLEt was orally administered to MD and SD rats at 100, 200 and 400 mg/kg doses for 1 day to determine antihyperglycemic activity. The 400 mg/kg dose was administered daily for 3 weeks to assess glycemic control and hypolipidemic effect.

Results

CLEt showed dose dependant fall in fasting blood glucose (FBG). After 5 h of extract administration at 400 mg/kg dose, FBG was reduced by 13.9% and 17.4% in MD and SD rats respectively. After 3 weeks treatment, CLEt produced significant reduction in FBG and glycosylated haemoglobin (GHb) in both MD and SD rats. Serum lipid levels were reversed towards normal in extract fed MD and SD rats.

Conclusions

The results demonstrate that CLEt possesses potent antihyperglycemic and hypolipidemic activity in both MD and SD rats.     

齿叶白鹃梅叶对小鼠糖耐量的影响及降糖作用研究

目的:探讨齿叶白鹃梅叶对正常和糖尿病小鼠糖耐量的影响以及对STZ诱导糖尿病小鼠的降糖作用.方法:采用腹腔注射链脲佐菌素(150 mg·kg-1)诱导小鼠造成糖尿病模型,先观察齿叶白鹃梅叶水提物和80%醇提物对正常和糖尿病小鼠糖耐量的改变;再观察齿叶白鹃梅叶的水提取物和80%醇提物物以及阳性药盐酸二甲双胍(333 mg·...     

地木耳菌粉对2型糖尿病大鼠血糖的影响

目的:研究云南野生地木耳粉对2型糖尿病大鼠血糖的影响。方法:采用高脂饲料饲养SD大鼠4周,按35 mg·kg-1腹腔注射给予链脲佐菌素(STZ)诱导2型糖尿病模型。糖尿病模型大鼠随机分为6组,地木耳粉低(25 mg·kg-1)、中(50 mg·kg-1)、高(100 mg·kg-1)剂量组,阳性组(盐酸二甲双胍200 mg·kg-1),模型组(等量生理盐水)和一直用普通饲料喂养的正常组,连续给药6周,检测各组大鼠体重、摄水量、排尿便量及空腹血糖。结果:给药6周后,与模型组比较,高、中、低剂量组大鼠的体质量明显增加,血糖、饮水量及排尿便量明显降低;3个剂量组的体重、摄水量、排尿便量及血糖有显著差异。与阳性组比较,3个剂量组的体重、摄水量、排尿便量及血糖无显著差异。结论:地木耳能缓解STZ致2型糖尿病大鼠症状,具有降低血糖的作用,且效果与地木耳浓度呈正相关。     

Protective Effect and Potential Mechanism of Ginkgo biloba Extract EGb 761 on STZ‐induced Neuropathic Pain in Rats

Diabetes induced neuropathic pain is recognized as one of the most difficult types of pain to treat with conventional analgaesics. EGb 761 is a standardized extract of Ginkgo biloba that has analgaesic and antiinflammatory properties and modulatory effects on key pain‐related molecules. We examined the effect of EGb 761 on streptozotocin (STZ)‐induced neuropathic pain behaviours and assessed its mechanism of action. Streptozotocin (20 mg/kg i.p for 5 days) was administered to induce experimental diabetes. Pain hypersensitivity to radiant heat was measured using the Dynamic Plantar Aesthesiometer to test the pain threshold. Diabetic rats exhibited mechanical allodynia and thermal hyperanalgaesia after the third week of STZ injection and concomitantly increased thiobarbituric acid reactive substance and nitric oxide concentration. The antioxidant enzymes level of superoxide dismutase and catalase was markedly reduced in STZ‐diabetic rats (p < 0.05). Systemic administration of EGb 761 (25, 50 and 100 mg/kg), starting after the third week following STZ injection, dose‐dependently reversed STZ‐induced thermal hyperanalgaesia and mechanical allodynia. Moreover, it reduced oxidonitrosative stress and concomitantly restored the level of antioxidant enzymes (p < 0.05) as compared with untreated diabetic rats. These results suggest that EGb 761 attenuated STZ‐induced neuropathic pain behaviours by inhibiting oxidative and nitrosative stress and may constitute a new approach for treatment of painful diabetic neuropathy. Copyright © 2012 John Wiley & Sons, Ltd.