Expression analysis of microRNAs and their target genes during experimental diabetic renal lesions in rats administered with ginsenoside Rb1 and trigonelline.

Purpose: To appraise the curative effect of ginsenoside Rb1 and trigonelline in diabetic nephropathy and to analyze the expression analysis of microRNAs and their target genes during experimental diabetic renal lesions in rats. Methods: Wistar rats were made diabetic by intraperitoneal injection of 55 mg/kg streptozotocin. According to their fasting blood glucose values and initial body weight, diabetic rats were assigned to specific groups and treated as follows: DN group (tap water, n = 10), A group (ginsenoside Rb1, 40 mg/kg, n = 10), B group (trigonelline, 20 mg/kg, n = 10) and the C group (ginsenoside Rb1 and trigonelline, 60 mg/kg, m(ginsenoside Rb1) : m (trigonelline) = 2:1, n = 10). The control group was treated with tap water (n = 10). All rats were gavaged with drugs or tap water once daily for 12 weeks. Results: Renal dysfunction, oxidative stress, and pathological alteration were significantly alleviated by a combination of ginsenoside Rb1 and trigonellin (C group). Some miRNAs were expressed differentially in Con, DN, A and C groups. Results of immunohistochemistry and western blotting showed that Wnt and ß-catenin were expressed differentially in Con, DN, and C groups. Conclusion: Ginsenoside Rb1 and trigonelline could prevent the development of diabetic renal lesions by regulating the expression of miR-3550 and further associating with the Wnt/ß-catenin signaling.

Urinary kidney injury molecule­1 as an early diagnostic biomarker of obstructive acute kidney injury and development of a rapid detection method.

The aim of the present study was to investigate whether urinary kidney injury molecule­1 (KIM­1) presents a suitable early diagnostic biomarker of obstructive nephropathy­induced acute kidney injury (AKI), and to develop a rapid detection method for urinary KIM­1. Obstructive AKI was induced in an experimental rat model by a unilateral ureteral obstruction (UUO) operation. Macro­ and micromorphological kidney alterations were determined by visual observation and hematoxylin and eosin (HE) staining, respectively. Kidney functions were evaluated by detecting urea nitrogen and creatinine levels in rat urine and blood. Urinary KIM­1 levels were measured using an enzyme­linked immunosorbent assay, and the protein expression levels of KIM­1, α­smooth muscle actin (α­SMA) and vimentin in kidney tissues were detected using immunohistochemical assays. In order to measure KIM­1 levels, colloidal gold immunochromatographic strips were developed based on the colloidal gold immunochromatographic assay. The results indicated that KIM­1 levels were significantly higher in the UUO group when compared with the Sham group. KIM­1 levels in the urine and kidney tissues exhibited a time­dependent increase, together with increasing obstructive AKI in the UUO group. In addition, KIM­1 levels were demonstrated to be a more sensitive biomarker of early obstructive AKI, when compared with α­SMA and vimentin. A colloidal gold­based immunochromatographic strip was developed, whereby the detection of urinary KIM­1 could be completed within 5­10 min. In conclusion, results of the present study demonstrated that urinary KIM­1 may be a valuable biomarker for the early diagnosis of obstructive AKI, and the use of a colloidal gold immunochromatographic strip may be a promising method for the rapid detection of urinary KIM­1.

Inhibitory effect of puerarin on vascular smooth muscle cells proliferation induced by oxidised low-density lipoprotein via suppressing ERK 1/2 phosphorylation and PCNA expression.

Puerarin, an isoflavonoid isolated from the traditional Chinese herbal medicine Pueraria lobata (Wild.) Ohwi, has been shown to process antioxidant, anti-inflammatory, anti-cancer, anti-hypercholesterolemic, and anti-hyperglycemic activities in vivo and in vitro. The aim of the present study was to investigate the antiproliferative effects and the possible mechanisms of puerarin in vascular smooth muscle cells (VSMCs) stimulated with oxidised low-density lipoprotein (ox-LDL). VSMCs were cultured and pretreated with different concentrations of puerarin (0, 1, 10, 50 µM) before stimulated by ox-LDL (50 µg/mL). Cell proliferation was evaluated by MTT assay. Flow cytometry was used to study the influence of puerarin on cell cycle. Proliferating cell nuclear antigen (PCNA) expression and phosphorylation levels of extracellular signal-regulated kinase (ERK) 1/2 were detected by western blotting analysis. The results indicated that puerarin significantly inhibited VSMCs proliferation induced by ox-LDL and phosphorylation of ERK 1/2. Furthermore, puerarin also blocked the ox-LDL-induced cell-cycle progression at G1/S-interphase and down-regulated the expression of PCNA of VSMCs. The results suggest puerarin inhibits ox-LDL-induced proliferation of VSMCs by suppressing ERK 1/2 phosphorylation and PCNA expression.

Icariin Attenuates High-cholesterol Diet Induced Atherosclerosis in Rats by Inhibition of Inflammatory Response and p38 MAPK Signaling Pathway.

Icariin is a flavonoid isolated from the traditional Chinese herbal medicine Epimedium brevicornum Maxim and has been reported to be effective for the treatment of a variety of cardiovascular diseases. The aim of the present study was to investigate the effect and mechanism of icariin on atherosclerosis (AS) using a high-cholesterol diet (HCD)-induced rat model. Seventy male Wistar rats were divided into five groups: 20 in the control group, 20 in the AS group, 10 in the simvastatin group, 10 in the low-dose icariin group, and 10 in the high-dose icariin group. A HCD and vitamin D3 were administered to establish AS rat model. The five groups of rats received daily intragastric administration of normal saline, simvastatin, or icariin (30 mg/kg/d, 60 mg/kg/d) for 4 weeks. The levels of blood lipids, superoxide dismutase (SOD), and malonaldehyde (MDA) were measured. The mRNA levels of interleukin (IL)-6 and tumor necrosis factor (TNF)-α were analyzed by real-time RT-PCR, and the serum levels of IL-6 and TNF-α were measured using ELISA kit. In addition, the expression of phosphorylated p38 (p-p38) MAPK was detected by Western blot analysis. The results indicated that AS rat models were successfully constructed. In the AS group, the levels of blood lipids including total cholesterol (TC), triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C), and MDA were significantly increased, while high-density lipoprotein-cholesterol (HDL-C) and SOD were significantly decreased, compared with those in the control group. However, icariin succeeded in improving these biochemical parameters towards the normal values in the control group. In the simvastatin group and the icariin groups, the serum levels of IL-6 and TNF-α and the related tissue mRNA levels, as well as the expression of p-p38 MAPK, were markedly reduced compared with the AS group. In conclusion, the present study indicated that icariin inhibited the HCD-induced dyslipidemia in rats, the mechanisms may be associated with the anti-inflammation, anti-oxidative stress, and downregulation of p-p38 MAPK by icariin.

Role of tissue transglutaminase in the pathogenesis of diabetic cardiomyopathy and the intervention effect of rutin.

The aim of this study was to investigate the role of tissue transglutaminase (tTG) in the pathogenesis of diabetic cardiomyopathy (DCM) and the intervention effect of rutin. DCM was induced in rats by the injection of streptozotocin (STZ; 25 mg/kg). After a preliminary examination, the rats were randomly divided into four groups: Control (n=8), STZ-induced DCM (n=8), STZ + positive drug (captopril; n=6) and STZ + rutin (n=8) groups. The DCM model was evaluated using blood sugar values, serum enzyme levels, hematoxylin and eosin staining and Masson's staining, ex vivo. The protein and mRNA expression of tTG was assessed with immunohistochemistry, western blotting and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The rat model of DCM was successfully established by STZ administration, and the expression levels of tTG were significantly increased in the DCM model. Following the injection of captopril or rutin, the blood sugar values, collagen content and expression levels of tTG were gradually reduced and serum enzyme levels were increased, as compared with those in the STZ-induced DCM group. In conclusion, tTG plays an important role in STZ-induced DCM. In addition, rutin may inhibit the expression of tTG and regulate myocardial injury in STZ-induced DCM.

Fenugreek Prevents the Development of STZ-Induced Diabetic Nephropathy in a Rat Model of Diabetes.

The present study aims to examine the protective effect of fenugreek and the underlying mechanism against the development of diabetic nephropathy (DN) in streptozotocin- (STZ-) induced diabetic rats. A rat model of diabetes was successfully established by direct injection of STZ and then the rats were administered an interventional treatment of fenugreek. Parameters of renal function, including blood glucose, albuminuria, hemoglobin A1c (HbA1c), dimethyl formamide (DMF), blood urine nitrogen (BUN), serum creatinine (Scr), and kidney index (KI), were detected in the three groups (Con, DN, and DF). Oxidative stress was determined by the activity of antioxidase. Extracellular matrix (ECM) accumulation and other morphological alterations were evaluated by means of immunohistochemistry and electron microscope. Quantitive (q)PCR was employed to detect the mRNA expression of transforming growth factor-ß1 (TGF-ß1) and connective tissue growth factor (CTGF) and protein expression was determined with western blot analysis. DN rats in the present study demonstrated a significant renal dysfunction, ECM accumulation, pathological alteration, and oxidative stress, while the symptoms were evidently reduced by fenugreek treatment. Furthermore, the upregulation of TGF-ß1 and CTGF at a transcriptional and translational level in DN rats was distinctly inhibited by fenugreek. Consequently, fenugreek prevents DN development in a STZ-induced diabetic rat model.

Quercetin provides greater cardioprotective effect than its glycoside derivative rutin on isoproterenol-induced cardiac fibrosis in the rat.

Quercetin exhibits numerous pharmacological effects, including the capacity for cardioprotection. This study aimed to investigate whether quercetin or its glycoside derivative rutin has any protective action against isoproterenol (ISO) induced cardiac fibrosis, and investigate the structure-activity relationship. Male Wistar rats were injected subcutaneously with ISO (15 mg·(kg body mass)(-1)) to induce experimental cardiac fibrosis. The cardioprotective effect of co-treatment with quercetin (25 or 50 mg·kg(-1)) or rutin (25 or 50 mg·kg(-1)) was investigated in ISO-induced cardiac fibrosis in rats. The administration of quercetin and rutin signifcantly decreased the cardiac weight index and myocardial enzyme activity, increased the activity of superoxide dismutase in the serum, and inhibited the ISO-induced increase in angiotensin II and aldosterone in the plasma. Furthermore, overexpression of transforming growth factor ß1 (TGF-ß1), connective tissue growth factor (CTGF), and excessive deposition of extracellular matrix (ECM) in isoproterenol-treated myocardial tissues were normalized by quercetin and rutin. Our results suggest that both quercetin and rutin exhibited cardioprotective effects in cardiac fibrosis induced by ISO in the rat heart. Moreover, the effects of rutin are weaker than quercetin at the same dose. The mechanism of these effects may be related to antioxidative stress, inhibition of the renin-angiotensin-aldosterone system, decrease in the expression of TGF-ß1 and CTGF, and the subsequent reduction in the deposition of the ECM.

The effect of DHEA treatment on the oxidative stress and myocardial fibrosis induced by Keshan disease pathogenic factors.

Oxidative stress induced by the combined deficiencies of selenium (Se) and vitamin E (VE) is considered the basic factor of Keshan disease (KD). Dehydroepiandrosterone (DHEA) is a naturally occurring adrenal androgen that has antioxidant properties. We found that a Se- and VE-deficient diet induced KD lesions in rats, while 0.05, 0.125, and 0.25 g/kg DHEA caused a concentration-dependent inhibition in the development of oxidative stress and extracellular matrix (ECM) deposition in the left ventricles of the Se- and VE-deficient rats. In addition, DHEA counteracted activation of NFκB as well as the subsequent increase in TGFß-1 and CTGF induced by the Se- and VE-deficient diet. These studies suggested that DHEA prevents oxidative stress and might be useful in treating Se and VE deficiency-related KD. These effects were based on its antioxidant effects and ECM deposition inhibition in left ventricles.

[Expression and implication of angiotensin II type 1 receptor in myocardial fibrosis of rats].

OBJECTIVE: To investigate the expression and pathobiological implications of angiotensin II type 1 receptor (AT1R) in development of myocardial fibrosis of rats. METHODS: Rat myocardial necrosis model was established using isoproterenol injection (15 mg/kg). Rat serum aspartate transaminase (AST), lactate dehydrogenase (LDH), creatine kinase (CK) and creatine kinase isoenzymes (CK-MB) were detected by MD-100 automatic biochemical analyzer. Masson staining was used to evaluate the morphological changes. The expression of AT1R protein was determined by immunohistochemistry and its mRNA expression was analyzed by RT-PCR. The expression of collage type I and III was determined by immunohistochemistry. RESULTS: Serum LDH, CK and CK-MB reached their peaks at 4 h (chi2 = 16.90, P < 0.05), and AST achieved its peak in 6 h (chi2 = 16.90, P < 0.05). AT1R mRNA expression was increased 2 - 12 h after isoproterenol injection, but no statistical significance (P > 0.05) was observed comparing with the control. However, a significant AT1R mRNA increase was present at 24 h and decreased gradually after 48 h, and back to the control level after 3 weeks. Protein expression of AT1R increased proportionally with the severity of the fibrosis. CONCLUSIONS: AT1R mRNA and protein expressions increase significantly during myocardial ischemia, and is closely correlated with the fibrosis. These findings indicate that AT1R may play an important role in the pathogenesis of myocardial fibrosis.

[Ameliorative effect of ginseng glycopeptide on cross-linking of rat tail tendon collagen].

OBJECTIVE: To investigate the ameliorative effect of ginseng glycopeptide on cross-linking of rat tail tendon collagen. METHOD: ELISA was used to determine the inhibitory effect of ginseng glycopeptide on cross-linking of rat tail tendon collagen in vitro. After ginseng glycopeptide was intraperitoneally administrated to streptozotocin-induced diabetic rats for 12 weeks, the acid solubility, limited pepsin degradation properties and solubility in SDS-2-mercaptoethanol of the rat tail tendon collagen were determined, and the effect of ginseng glycopeptide on the tail tendon collagen cross-linking was evaluated. RESULT: Ginseng glycopeptide inhibited significantly the cross-linking of rat tail tendon collagen in vitro. The solubility of the tail tendon collagen (in acid, pepsin and SDS-2-mercaptoethanol) was markedly decreased in diabetic rats and ginseng glycopeptide-treated diabetic rats had significantly an increase in the collagen solubility in the above-mentioned solutions, suggesting that ginseng glycopeptide decreased severity of the collagen cross-linking. CONCLUSION: Ginsengglycopeptide exhibits an significantly ameliorative effect on cross-linking of rat tail tendon collagen.