Inhibition of Coix seed extract on fatty acid synthase, a novel target for anticancer activity

Ethnopharmacological relevance

Coix seed has been traditionally used to treat cancers in folk medicine.

Aim of the study

Study the anticancer action mechanism of Coix seed extract.

Materials and methods

After the treatment with Coix seed extract (10 μl/ml), the residual activity of fatty acid synthase (FAS) as overall reaction, β-ketoacyl reduction, enoyl reduction, and acetyl acetyl coenzyme A (AcAcCoA) reduction was separately detected at 340 nm in the UV-190 spectrophotometer. After rats were administrated Coix seed extract (2.5, 5.0, and 10.0 ml/kg) intragastrically for 10 days consecutively, activities of FAS, malate dehydrogenase (MDH), lipid protein lipase (LPL), hepatic lipase (HL), triglyceride (TG), and glucose-6-phosphate dehydrogenase (G-6-PD) in the plasma, liver and fatty tissues were determined.

Results

Experiments in vitro showed that the inhibition of Coix seed extract on FAS activity was significant and dose dependent, and two active sites inhibited were β-ketoacyl reductases (KR) and enoyl reductase (ER). Experiments in vivo showed that Coix seed extract inhibited FAS activity in the liver, and elevated LPL and HL activity in the plasma, and effected G-6-PD activity.

Conclusions

The study supports that FAS is a novel target for anticancer activity, and provides a theoretical foundation for the wide application of Coix seed extract in traditional medicine.     

Attenuation of diabetic nephropathy by Chaihuang-Yishen granule through anti-inflammatory mechanism in streptozotocin-induced rat model of diabetics

Ethnopharmacological relevance

Traditional Chinese medical herbs have been used in China for a long time to treat different diseases. Based on traditional Chinese medicine (TCM) principle, Chaihuang-Yishen granule (CHYS) was developed and has been employed clinically to treat chronic kidney disease including diabetic nephropathy (DN). The present study was designed to investigate its mechanism of action in treatment of DN.

Materials and methods

Diabetic rats were established by having a right uninephrectomy plus a single intraperitoneal injection of STZ. Rats were divided into four groups of sham, diabetes, diabetes with CHYS and diabetes with fosinopril. CHYS and fosinopril were given to rats by gavage for 20 weeks. Samples from blood, urine and kidney were collected for biochemical, histological, immunohistochemical and molecular analyses.

Results

Rats treated with CHYS showed reduced 24 h urinary protein excretion, decreased serum TC and TG levels, but CHYS treatment did not affect blood glucose level. Glomerular mesangial expansion and tubulointerstitial fibrosis in diabetic rats were significantly alleviated by CHYS treatment. Moreover, CHYS administration markedly reduced mRNA levels of NF-κB p65 and TGF-β1, as well as decreased protein levels of NF-κB p65, MCP-1, TNF-α and TGF-β1 in the kidney of diabetic rats.

Conclusions

CHYS ameliorates renal injury in diabetic rats through reduction of inflammatory cytokines and their intracellular signaling.     

Protective effect of Icariin on the early stage of experimental diabetic nephropathy induced by streptozotocin via modulating transforming growth factor β1 and type IV collagen expression in rats

Ethnopharmacological relevance

Icariin is a major constituent of flavonoid isolated from the plant Herba epimedii, which is used as a traditional Chinese medicine to nourish the kidney and reinforce yang. Therefore, the pharmacological studied of its diabetic nephropathy effect was undertaken to validate its traditional use.

Materials and methods

Diabetes was induced in male Sprague-Dawley rats by an injection of streptozotocin (40 mg/kg i.v.). Sustained blood glucose levels (>16.7 mmol/l) were considered as diabetic and selected for experimentation. Thirty rats were randomly divided into three groups: control, diabetic, diabetic + Icariin (80 mg/kg, i.g.) administered 8 weeks from 5th to 12th week. Experiment was carried out at the beginning of 13th week. All rats were anaesthetized and then were killed to remove kidneys. Blood glucose, serum creatinine (Cr), blood urea nitrogen (BUN), the activity of superoxide dismutase (SOD), malondialdehyde (MDA) and hydroxyproline (Hyp) in the kidney tissue were measured. Glomerular morphology was observed by light microscopy. Immunohistochemistry and Western blot were employed to determine the proteins levels of TGF-β₁ and type IV collagen.

Results

The enhancement of Cr and BUN was found in model group, which was significantly attenuated by treatment with Icariin. Meanwhile, elevated MDA and Hyp levels in renal tissue as well as decreased SOD activities in renal tissue were significantly remitted by Icariin. The renal pathological changes in Icariin treatment group were ameliorated. Furthermore, the Icariin decreased the expression of TGF-β₁ and collagen IV protein.

Conclusions

Icariin can evidently relieve renal damage in rats with diabetic nephropathy induced by STZ, which might be related to modulating the expression of collagen IV and TGF-β₁ protein.     

Lipid-lowering effects of Danhong injection on hyperlipidemia rats

Ethnopharmacological relevance

Danhong injection (DHI), a Chinese medical product extracted from Radix et Rhizoma Salviae Miltiorrhizae (Salvia miltiorrhiza Bge., Labiatae, Danshen in Chinese) and Flos Carthami (Carthamus tinctorius L., Compositae, Honghua in Chinese), has been reported to have anti-inflammatory, anti-oxidative and anti-fibrinolytic properties and is used extensively for the clinical treatment of cardiovascular disease in clinic. This study aimed to investigate the preventive and therapeutic effects of DHI on hyperlipidemia.

Materials and methods

Forty-eight adult male Sprague-Dawley rats were randomly divided into four groups: normal control (NC), model control (MC) and DHI-treated at doses of 1.0 mL/kg and 2.0 mL/kg. The effects of DHI on serum triglyceride (TG), total cholesterol (TC), glucose, high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) were evaluated and insulin was determined by enzyme-linked immunosorbent assay (ELISA). Moreover, the expression of acetyl-CoA carboxylase 1 (ACC1), fatty acid synthase (FAS), carnitine palmitoyl transferase 1 (CPT1), hydroxymethylglutaryl-CoA reductase (HMGR) and peroxisome proliferator-activated receptor alpha (PPAR-α) in liver were determined by real-time PCR.

Results

Compared with the MC group, rats treated with DHI had significantly reduced TG, TC, LDL-C and arteriosclerosis index (AI). Expression of FAS and HMGR mRNA was significantly reduced, whereas the CPT1 and PPAR-α were significantly increased.

Conclusion

DHI treatment was accompanied by significantly increased lipolysis in the liver and decreased fatty acid synthesis. The insights gained from this study will improve both understanding of the mechanisms involved in the effect of DHI on hyperlipidemia and the pharmacological rationale for the use of DHI in diseases caused by lipid metabolic disorders.     

Antidiabetic activity of Ficus amplissima Smith. bark extract in streptozotocin induced diabetic rats

Ethnopharmacological relevance

Ficus amplissima commonly known as kal-itchchi have a long history of use in Ayurveda, Siddha and Unani herbal preparations in Indian traditional system of medicine. It has been used in folklore medicine for the treatment of diabetes.

Aim

The aim of the present study was to evaluate the effect of methanolic extract of the bark of Ficus amplissima (FAB) in streptozotocin-induced diabetic rats.

Materials and methods

Oral administration of FAB bark at the doses of 50 mg/kg, 100 mg/kg and 150 mg/kg was studied in normal, glucose-loaded and STZ—induced diabetic rats.

Results

The three doses caused significant reduction in blood glucose levels in all the models. The effect was more pronounced in 50 mg/kg and 100 mg/kg than 150 mg/kg. FAB also showed significant increase in serum insulin and body weight. The glycogen content in liver, skeletal muscle, total protein contents were markedly increased and marker enzymes of hepatic function of STZ-induced diabetic rats while there was significant reduction in the levels of serum triglyceride and total cholesterol. FAB also showed significant anti-lipid peroxidative effect in the pancreas of STZ-induced diabetic rats. The anti-diabetic effect of FAB was compared with glibenclamide, a well known hypoglycemic drug. Histological analysis showed the regenerative effect of FAB on the β-cells of diabetic rats.

Conclusion

Results of this experimental study indicated that FAB possessed anti-diabetic and antioxidant activities. Hence it could be used as a natural source of antidiabetic (Type-I) and antioxidant drug.     

Vitexin and isovitexin from the Leaves of Ficus deltoidea with in-vivo α-glucosidase inhibition

Ethnopharmacological relevance

The leaves of Ficus deltoidea are used as a traditional medicine by diabetes patients in Malaysia.

Aim of the study

The objective of the study is to identify and evaluate bioactive constituents with in vivo α-glucosidase inhibition.

Materials and Methods

The partitioned extracts, subfractions and pure bioactive constituents were subjected to α-glucosidase inhibition assay. The identified bioactive constituents were administered orally to sucrose loaded normoglycemic mice and induced diabetic rats. The postprandial blood glucose levels were monitored at 30 min interval. Acute toxicity was evaluated in both normoglycemic mice and induced diabetic rats.

Results

Bioactivity guided fractionation led to the isolation of both vitexin (1) and isovitexin (2). Oral administration of 1 mg/kg of either vitexin (1) or isovitexin (2) significantly (p<0.05) reduced the postprandial blood glucose level in sucrose loaded normoglycemic mice at 30 min. The percentage of postprandial blood glucose reduction was highest in sucrose loaded induced diabetic rats administered orally with 200 mg/kg of vitexin (1) or 100 mg/kg of isovitexin (2). Both vitexin (1) and isovitexin (2) did not exert any signs of toxicity at the highest dose of 2 g/kg administered orally to normoglycemic mice and induced diabetic rats.

Conclusion

Both the C-glycosyl bioflavonoids, namely, vitexin (1) and isovitexin (2) exhibited in vivo α-glucosidase inhibition.     

Efficacy of ginseng adventitious root extract on hyperglycemia in streptozotocin-induced diabetic rats

Ethnopharmacological relevance

Ginseng has various bioactive effects on human health including its potential activity of improving the glucose homeostasis and insulin sensitivity.

Materials and methods

Tissue culture raised mountain ginseng adventitious root (TCMGARs) extract enriched with ginsenosides was used as experimental material. Streptozotocin-induced diabetic ‘Sprague Dawley’ male rats were used as experimental systems and were fed with Tissue culture raised mountain ginseng adventitious root extract. Field cultivated Korean ginseng root extract fed rats were used as positive control and several indices such as body weight, blood glucose level and other serological indicators were tested.

Results

Chemical profile showed TCMGARs were rich in varied ginsenosides especially Rb1, Rb2, Rc, Rd, Rg3, and Rh2 when compared to field cultivated Korean ginseng. TCMGARs extract at dosage levels of 250 and 500 mg/kg body weight significantly lowered the blood glucose, total cholesterol and triglyceride content in streptozotocin-induced diabetic rats.

Conclusion

The data of in vivo experiments on anti-glycemic effects of TCMGARs proves their efficacy and also their use as dietary supplement.     

Antidiabetic effects of Artemisia sphaerocephala Krasch. gum,a novel food additive in China,on streptozotocin-induced type 2 diabetic rats

Aim of the study

Since ancient times, practicians of traditional Chinese medicine have discovered that Artemisia sphaerocephala Krasch. (Asteraceae) seed powder was useful for the treatment of diabetes. Artemisia sphaerocephala Krasch. gum (ASK gum), which is extracted from seed powder of the plant, is a novel food additive favored by the food industry in China. The objective of this study was to determine the antidiabetic function of ASK gum on type 2 diabetes.

Materials and methods

Type 2 diabetic rat model was induced with high fat diet and low dose of streptozotocin (STZ). The effects of ASK gum on hyperglycemia, hyperlipemia, insulin resistance, and liver fat accumulation in type 2 diabetic rats were evaluated. The results were compared to those of normal rats and diabetic rats treated with metformin.

Results

The addition of ASK gum to the rats’ food supply significantly lowered fasting blood glucose, glycated serum protein, serum cholesterol, and serum triglyceride in type 2 diabetic rats, and significantly elevated liver glucokinase, liver glycogen, and serum high density protein cholesterol in the diabetic rats. ASK gum significantly reduced insulin resistance and liver fat accumulation of type 2 diabetes.

Conclusion

: Artemisia sphaerocephala Krasch. gum can alleviate hyperglycemia, hyperlipemia and insulin resistance of type 2 diabetes.     

Synergistic interaction between Astragali Radix and Rehmanniae Radix in a Chinese herbal formula to promote diabetic wound healing

Ethnopharmacological relevance

Astragali Radix (AR) and Rehmanniae Radix (RR) are two traditional Chinese medicines widely used in China for treating diabetes mellitus and its complications, such as diabetic foot ulcer.

Aim of study

In our previous study, a herbal formula NF3 comprising AR and RR in the ratio of 2:1 was found effective in enhancing diabetic wound healing in rats through the actions of tissue regeneration, angiogenesis promotion and inflammation inhibition. The aims of the present study were to investigate the herb–herb interaction (or the possible synergistic effect) between AR and RR in NF3 to promote diabetic wound healing and to identify the principal herb in the formula by evaluating the potencies of individual AR and RR in different mechanistic studies.

Materials and methods

A chemically induced diabetic foot ulcer rat model was used to examine the wound healing effect of NF3 and its individual herbs AR and RR. For mechanistic studies, murine macrophage cell (RAW 264.7) inflammation, human fibroblast (Hs27) proliferation and human endothelial cell (HMEC-1) migration assays were adopted to investigate the anti-inflammatory, granulation formation and angiogenesis-promoting activities of the herbal extracts, respectively.

Results

In the foot ulcer animal model, neither AR nor RR at clinical relevant dose (0.98 g/kg) promoted diabetic wound healing. However, when they were used in combination as NF3, synergistic interaction was demonstrated, of which NF3 could significantly reduce the wound area of rats when compared to water group (p < 0.01). For anti-inflammation and granulation formation, AR was more effective than RR in inhibiting lipopolysaccharide (LPS)-induced nitric oxide production from RAW 264.7 cells and promoting Hs27 fibroblast proliferation. In the aspect of angiogenesis promotion, only NF3 promoted cell migration of HMEC-1 cells.

Conclusions

AR plays a preeminent role in the anti-inflammatory and fibroblast-proliferating activities of NF3. The inclusion of RR, however, is crucial for NF3 to exert its overall wound-healing as well as the underlying angiogenesis-promoting effects. The results of present study justified the combined usage of AR and RR in the ratio of 2:1 as NF3 to treat diabetic foot ulcer and illustrated that AR is the principal herb in this herbal formula.     

Anti-diabetic activity of extract from Persea americana Mill. leaf via the activation of protein kinase B (PKB/Akt) in streptozotocin-induced diabetic rats

Ethnopharmacological relevance

The leaves of Persea americana Mill. (Lauraceae) have been popularly used in the treatment of diabetes in countries in Latin America and Africa.

Aim of the study

To investigate the hypoglycaemic properties and to determine the molecular mechanism by which the hydroalcoholic extract of the leaves of Persea americana reduce blood glucose levels in streptozotocin (STZ)-induced diabetes in rats via the enzymatic pathway of protein kinase B (PKB/Akt).

Methods

The hydroalcoholic extract of the leaves of Persea americana (0.15 and 0.3 g/kg/day), vehicle and metformin (0.5 g/kg/day) were administered orally to STZ-diabetic rats (n = 7/group) for 4 weeks. Changes in body weight, food and water intake, fasting glucose levels and oral glucose tolerance were evaluated. Phosphorylation and the expression of PKB in the liver and soleus muscle were determined by Western blot.

Results

The hydroalcoholic extract of the leaves of Persea americana reduced blood glucose levels and improved the metabolic state of the animals. Additionally, PKB activation was observed in the liver and skeletal muscle of treated rats when compared with untreated rats.

Conclusion

The results indicate that the hydroalcoholic extract of the leaves of Persea americana has anti-diabetic properties and possibly acts to regulate glucose uptake in liver and muscles by way of PKB/Akt activation, restoring the intracellular energy balance.     

Arnebin-1 promotes the angiogenesis of human umbilical vein endothelial cells and accelerates the wound healing process in diabetic rats

Ethnopharmacological relevance

Zicao is a traditional wound healing herbal medicine that has been used for several hundred years in China. A survey of the published literatures revealed that arnebin-1, one of the naphthoquinone derivatives, played the most important role in wound healing property of this plant. However, whether arnebin-1 affects angiogenesis in vitro and has an effect on wound healing process in diabetic rats remains enigmatic. To investigate the effect of arnebin-1 with or without VEGF on proliferation, migration and tube formation of HUVECs in vitro and the effect of its topical application in the form of ointment on wound healing in a cutaneous punch wound model of alloxan-induced diabetic rats in vivo.

Materials and methods

The pro-angiogenic functions of arnebin-1 on HUVECs including proliferation, migration and angiogenesis were evaluated through MTT assay, wound healing assay, transwell assay and tube formation assay in vitro. Male Sprague-Dawley rats were injected intraperitoneally with alloxan to induce type ? diabetic rats. Three wounds were created in each rat on the dorsal surface, and then divided to be basement treated, arnebin-1 ointment treated and untreated group correspondingly. The indicators including wound closure rate and histological evaluation were investigated on day 4 and 7 post-wounding.

Results

Without VEGF, arnebin-1 did not affect the proliferation of HUVECs significantly, but had a positive effect on cell migration and tube formation. However, in the presence of minimal VEGF, Arnebin-1 could increase the proliferation, enhance the migration and promote the tube formation of HUVECs significantly. The wound closure rate was increased significantly in arnebin-1 treated group compared to that of untreated and basement treated groups in diabetic rats, and the histological evaluation also showed well organized dermal layer, reduced number of macrophages, increased number of fibroblasts, remarkable degree of neovascularization and epithelization in arnebin-1 treated group.

Conclusion

These findings suggest that arnebin-1 has a pro-angiogenic effect, and a synergetic effect with VEGF promotes the wound healing process in diabetic rats.     

Antidiabetic and antioxidant activities of Toddalia asiatica (L.) Lam. leaves in Streptozotocin induced diabetic rats

Ethnopharmacological relevance

The leaves of Toddalia asiatica (L.) Lam. have been utilized traditionally for the cure of diabetes.

Aim of the study

The present study was aimed to assess the antidiabetic and antioxidant effects of T. asiatica leaves in Streptozotocin (STZ) induced diabetic rats.

Materials and methods

The phytochemical screening, total phenolic content, HPLC analysis, acute toxicity study and oral glucose tolerance test were carried out. Glucose lowering effect of the hexane, ethyl acetate and methanol extracts of T. asiatica leaves was studied in STZ-induced diabetic rats. The antidiabetic and antioxidant activities were studied for the ethyl acetate extract. The effects of extracts on blood glucose, body weight, plasma insulin, total protein, liver glycogen, plasma enzymes (SGOT, SGPT and ALP) and activities of SOD, CAT and GPx were analyzed.

Results

T. asiatica leaves ethyl acetate extract (TALEe) showed highly significant blood glucose lowering effect. Phytochemical evaluation of TALEe showed the presence of alkaloids, terpenoids, cumarins, flavonoids and phenolic compounds. The total phenolic content of TALEe was 126 mg of gallic acid equivalents/g extract. HPLC analysis revealed the presence of flindersine and ulopterol. Acute toxicity study of TALEe revealed no death or toxicity. The oral glucose tolerance test showed lowered area under curve (AUC_glucose) values in TALEe treated rats. After treatment with TALEe (250 and 500 mg/kg) for 28 days there was a significant decrease in blood glucose, plasma enzymes (SGOT, SGPT and ALP) and significant increase in body weight, total protein, serum insulin and liver glycogen levels in treated diabetic rats. The activities of antioxidant enzymes SOD, CAT and GPx were reversed to near normal in treated diabetic rats. Histopathology of pancreas in TALEe treated groups showed regeneration of β-cells.

Conclusion

The results of the experiments showed that TALEe exerted significant antidiabetic and antioxidant effects in STZ-induced diabetic rats justifying its traditional use.     

Anti-urolithiatic effects of Punica granatum in male rats

Ethnopharmacological relevance

The traditional use of Punica granatum has been reported to regulate urine discharge and controls the burning sensation of urine.

Materials and methods

Animals model of calcium oxalate urolithiasis was developed in male rats by adding ethylene glycol 0.75% in drinking water. The Punica granatum chloroform extract (PGCE) and Punica grantum methanol extract (PGME) orally at 100, 200 and 400 mg/kg, respectively, were administered along with ethylene glycol for 28 days. On 28 day, 24 h urine was collected from individual rats and used for estimation of urine calcium, phosphate and oxalate. The serum creatinine, urea and uric acid levels were estimated in each animal. The kidney homogenate was used for the estimation of renal oxalate contents. The paraffin kidney sections were prepared to observe the CaOx deposits.

Results

The ethylene glycol control (Gr.-II) had significant (P < 0.001 vs. normal) increase in levels of urine oxalate, calcium and phosphate, serum creatinine, urea and uric acid and renal tissues oxalates, as compared to normal (Gr.-I). The paraffin kidney sections show significant histopathological changes. The treatment of PGCE and PGME at 100, 200 and 400 mg/kg doses, significantly (P < 0.001 vs. control) decreased the urine oxalate, calcium and phosphate, renal tissue oxalates and serum creatinine, urea and uric acid, in EG induced urolithiasis after 28 days.

Conclusions

The PGCE and PGME at the doses of 400 mg/kg, found to be more effective in decreasing the urolithiasis and regeneration of renal tissues in male rats.     

Antidiabetic effects of malonyl ginsenosides from Panax ginseng on type 2 diabetic rats induced by high-fat diet and streptozotocin

Ethnopharmacology relevance

Ginseng (Panax ginseng C. A. Meyer) has been recorded to treat ‘Xiao-ke’ (emaciation and thirst) symptom in many ancient Chinese medical literatures (such as ‘Shen Nong Ben Cao Jing’) for thousands of years. ‘Xiao-ke’ symptom, in general, indicates diabetes mellitus.

Aim of the study

Malonyl ginsenosides (MGR) are natural ginsenosides which exist in both fresh and air-dried ginseng. The objective of this study is to determine the antidiabetic function of MGR on type 2 diabetes.

Materials and methods

High fat diet-fed and streptozotocin-induced diabetic rats were treated with 50 and 100 mg/kg/d of MGR or vehicle for 3 weeks. The effects of MGR on fasting blood glucose (FBG), intraperitoneal glucose tolerance test (IPGTT), serum insulin (SI), insulin tolerance test (ITT), body weight, total cholesterol (TC), and triglyceride (TG) levels in type 2 diabetic rats were measured.

Results

After 3 weeks of treatment, MGR administration showed significantly lower FBG levels compared to the diabetic control group. In glucose tolerance test, IPGTT data showed that both MGR 50 and 100 mg/kg groups significantly increased the glucose disposal after glucose load. The ITT also showed improvement of insulin sensitivity during 120 min of insulin treatment. In addition, MGR reduced TG and TC contents while showed no effect on body weight in diabetic rats.

Conclusion

The findings from this study suggest that MGR can alleviate hyperglycemia, hyperlipemia and insulin resistance of type 2 diabetes.     

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.     

Inhibition mechanism of compound ethanol extracts from Wuweizi (Fructus Schisandrae Chinensis) on renal interstitial fibrosis in diabetic nephropathy model mice

Objective

To evaluate inhibition effect and mechanism of compound ethanol extracts from Wuweizi (Fructus Schisandrae Chinensis), Chuanxiong (Rhizoma Chuanxiong) and Muli (Cocha Ostreae) (FRC) on glomerular and tubular interstitial fibrosis in streptozocin (STZ)-induced diabetic nephropathy (ND) model mice.

Methods

Twenty-seven male C57BL/6 mice were divided randomly into 3 groups: nondibetic (ND), STZ-induced diabetic (D), and STZ-induced diabetic that were treated with 5 g · kg⁻¹ · day⁻¹of FRC by oral gavage (D_FRC), with 9 in each group. The protein expressions of E-cadherin, α-smooth muscle actin (α-SMA), Plasminogen Activator Inhibitor-1 (PAI-1) in renal tissues were investigated by Western blotting. The expressions of fibronectin (FN) and α-SMA were detected by immunohistochemical method. The morphological changes of renal tissues were observed under a microscope.

Results

Renal tissues in the D_FRC group showed a lessened degree of fibrosis. Meanwhile, the expressions of FN, α-SMA and PAI-1 were significantly lower in the D_FRC group than those in the D group (all P<0.05).

Conclusion

FRC can ameliorate the DN in the C57BL/6 mice, and its mechanism may relate to inhibition on the epithelial to mesenchymal transdifferentiation, endothelial-myofibroblast transition and PAI-1 expression.     

Renoprotection of Danshen Injection on streptozotocin-induced diabetic rats,associated with tubular function and structure

Ethnopharmacological relevance

Danshen Injection, the aqueous extracts of Radix Salvia miltiorrhiza (S. miltiorrhiza), is one of the most commonly used traditional Chinese herbs in chronic renal failure treatment. In present study, the mechanism of the renoprotective effect of Danshen Injection was analyzed on streptozocin (STZ)-induced diabetic rats.

Materials and methods

Diabetic experimental model was established in male Sprague-Dawley (SD) rats by intraperitoneal injection of STZ. Rats with blood glucose concentration of higher than 300 mg/dl were intraperitoneally administered with Danshen Injection at a dose of 0.78 ml/kg day. The blood glucose, 24 h urinary protein excretion, serum creatinine (sCr), blood urea nitrogen (BUN), advanced glycation end products (AGEs), lipid peroxide (LPO), antioxidant enzyme of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), transforming growth factor-β1 (TGF-β1), and histomorphological changes in kidney of diabetic rats were analyzed during the course of Danshen Injection administration, as well as the tubular function index of albumin reabsorption of fluorescein isothiocyanate labeled bovine serum albumin (FITC-BSA).

Results

The intraperitoneal administration of Danshen Injection could ameliorate the physiological dysfunctions of increased 24 h urinary protein excretion((48.21±8.04)%), sCr((39.4±3.7)%), and BUN((43.37±6.74)%), alleviate the ultrastructural abnormalities of hypertrophy, matrix expansion, and fibrosis in glomerulus, decrease the TGF-β1 expression, AGEs and LPO accumulation, and increase the activity of SOD and GSH-Px in kidney of diabetic rats, but did not significantly influence the blood glucose. Besides these, the Danshen Injection administration also partly restored the decrease of megalin expression in tubules and reabsorptive function of FITC-BSA, in diabetic rats.

Conclusion

The renoprotection of Danshen Injection on diabetic rats was associated with the preservation of tubular function and structure from the hyperglycemia induced toxicities of inappropriate cytokines secretion, oxidative stress, advanced glycation stress, and megalin expression deletion.