Huangkui capsule attenuates renal fibrosis in diabetic nephropathy rats through regulating oxidative stress and p38MAPK/Akt pathways, compared to α-lipoic acid.

ETHNOPHARMACOLOGICAL RELEVANCE: In traditional Chinese medicine (TCM), Abelmoschus manihot (L.) medic (AM) is a natural medicinal plant used for the treatment of inflammatory diseases. Recently, Huangkui capsule (HKC), a Chinese patent medicine extracted from AM, has been widely applied to the clinical therapy of renal fibrosis in patients with early diabetic nephropathy (DN). However, the therapeutic mechanisms involved in vivo remain ambiguous. The goal of this study is to expound the mechanism in vivo of HKC in order to deepen the understanding of its clinical effects, by using the approaches of contrasting the dose-effects of HKC on oxidative stress (OS) in the kidney compared to α-lipoic acid (LA), and then demonstrating whether and how anti-oxidative properties of HKC or LA might be beneficial for the treatment of renal fibrosis in vivo. MATERIALS AND METHODS: Thirty-three rats were divided into 5 groups, a Sham group, a Vehicle group, a L-HKC group, a H-HKC group and a LA group. The different doses of HKC, LA and distilled water were daily administrated for 8 weeks after the induction of DN by the unilateral nephrectomy combined with streptozotocin (STZ) intraperitoneal injections. Rat's general status, biochemical parameters, renal histological changes and OS indicators, as well as the key protein expressions in p38 mitogen-activated protein kinase (p38MAPK)/serine-threonine kinase (Akt) signaling pathways and downstream cytokines including transforming growth factor (TGF)-ß1 and tumor necrosis factor (TNF)-α were examined, respectively. RESULTS: HKC and LA ameliorated body weight, kidney weight, urinary albumin and renal function including blood urea nitrogen and serum uric acid, attenuated renal fibrosis including the cell numbers and extracellular matrix rate in glomerulus, and controlled OS indicators including malondialdehyde, total superoxide dismutase, 8-hydroxy-2'-deoxyguanosine and nicotinamide adenine dinucleotide phosphate oxidase 4, but did not lower blood glucose in DN model rats. Among them, the anti-renal fibrosis effect of H-HKC was better than that of LA. In addition, HKC simultaneously down-regulated the protein expressions of phosphorylated p38MAPK, phosphorylated Akt (p-Akt), TGF-ß1 and TNF-α in the kidney of DN model rats, unlike HKC, LA only down-regulated p-Akt and TNF-α protein expressions. CONCLUSION: We have demonstrated that HKC, similar to LA, is renoprotective via attenuating OS and renal fibrosis in the DN rat model. The potential mechanisms by which HKC and LA exert their therapeutic effects in vivo are respectively through down-regulating the activation of p38MAPK and/or Akt pathways as well as the expressions of TGF-ß1 and/or TNF-α in the kidney. Our findings thus provide the useful information about a clinical combination of HKC and LA in early DN patients.

Ureic clearance granule, alleviates renal dysfunction and tubulointerstitial fibrosis by promoting extracellular matrix degradation in renal failure rats, compared with enalapril.

ETHNOPHARMACOLOGICAL RELEVANCE: Chinese herbal compound prescription has a unique therapeutic action on chronic kidney disease (CKD) in China. In clinics, Uremic Clearance Granules (UCG), a compounded Chinese patent medicine, has been frequently used to treat chronic renal failure (CRF) patients for nearly 30 years, however, the deep therapeutic mechanisms involved in vivo remain a challenge. This study aims to demonstrate the effects and mechanisms of UCG on renal dysfunction and tubulointerstitial fibrosis by regulating extracellular matrix (ECM) degradation and transforming growth factor (TGF)-beta1/Smad signaling activity in vivo, compared with enalapril. MATERIALS AND METHODS: Twenty-six rats were randomly divided into 4 groups, a sham-operated group (Sham group), a vehicle-intervened group (Vehicle group), a UCG-treated group (UCG group) (5g/kg/day) and an enalapril-treated group (Enalapril group) (20mg/kg/day). The rats with renal failure were induced by adenine (150 mg/kg/day) and unilateral ureteral obstruction (UUO), and killed on day 35 after the administration. Proteinuria, urinary N-acetyl-beta-D-glucosaminidase (UNAG), blood biochemical parameters, renal morphological changes, collagen type IV (CIV), matrix metalloproteinase (MMP)-2, MMP-9 and tissue inhibitors of metalloproteinase (TIMP)-1, as well as the key molecular protein expressions in TGF-beta1/Smad signaling pathway were observed, respectively. RESULTS: Adenine administration and UUO induced severe renal damages, as indicated by renal dysfunction, proteinuria and the marked histopathological injuries in the tubules and interstitium, which were associated with MMP-2/TIMP-1 imbalance and TGF-beta1/Smad signaling activity, as shown by up-regulation of the protein expressions of TGF-beta1, TGF-beta receptor type I (RI), TGF-beta receptor type II (RII), Smad2/3, phosphorylated-Smad2/3 (p-Smad2/3) and Smad4, as well as down-regulation of the protein expression of Smad7 in the kidney. UCG treatment, however, significantly not only attenuated renal dysfunction and tubulointerstitial fibrosis, but also improved the protein expressions of MMP-2, TIMP-1, TGF-beta1, TGF-beta RI, p-Smad2/3, Smad4 and Smad7 in the kidney. Besides, the effects of UCG were stronger than those of enalapril partly. CONCLUSION: UCG similar to enalapril, is renoprotective via ameliorating renal dysfunction and tubulointerstitial fibrosis in the renal failure model. The potential mechanisms by which UCG exerts its therapeutical effects in vivo are through promoting ECM degradation and regulating MMP-2/TIMP-1 balance or signaling molecular activity in TGF-beta1/Smad pathway in the kidney. These findings suggest that UCG treatment is undoubtedly useful in preventing the progression of CRF.

[Effects and mechanisms of huangkui capsule ameliorating renal fibrosis in diabetic nephropathy rats via inhibiting oxidative stress and p38MAPK signaling pathway activity in kidney].

OBJECTIVE: To demonstrate the effects and mechanisms of Huangkui capsule (HKC) on renal fibrosis in rats with diabetic nephropathy (DN). METHOD: Rats were randomly divided into 5 groups, the sham-operated group (Sham group, n = 5), the vehicle-given group (Vehicle group, n = 7), the low dose of HKC-treated group (L-HKC group, n = 7), the high dose of HKC-treated group (H-HKC group, n = 7) and the lipoic acid (LA)-treated group (LA group, n = 7). DN models were induced by intraperitoneal injection of streptozotocin (STZ,35 mg x kg(-1)) twice and unilateral nephrectomy. After models were successfully established, the rats in HKC and LA groups were daily administrated with HKC suspensions (0.75, 2 g x kg(-1)) or LA suspensions (60 mg x kg(-1)) respectively, and at the same time, the rats in Vehicle group were daily administrated with distilled water (2 mL) for 8 weeks. All rats were sacrificed at the end of week 8 to collect blood and renal tissues. UAlb, renal function, renal fibrotic morphologic characteristics, as well as oxidative stress (OS)-related markers, the protein expressions of the key signaling molecules in p38 mitogen-activated protein kinase (p38MAPK) signaling pathway, fibrogenic cytokines and inflammatory factors were examined respectively. RESULT: HKC, similar to LA, improved the general state of health, body weight, UAlb, BUN, UA and Alb in DN model rats. Of note, renal fibrosis was ameliorated in HKC groups,especially in H-HKC group which was better than that in LA group. In addition, HKC not only improved the main indexes of OS in the kidney like LA, but also down-regulated the protein expressions of phosphorylated-p38MAPK (p-p38MAPK), transforming growth factor (TGF)-ß1 and tumor necrosis factor(TNF)-α in the kidney, whereas, LA only decreased the protein expression of TNF-α in the kidney in DN model rats. CONCLUSION: HKC, similar to LA, has the actions of anti-OS in vivo. Moreover, HKC could attenuate renal fibrosis by suppressing the activation of p38MAPK signaling pathway and the protein expressions of fibrogenic cytokines and inflammatory factors in the kidney in DN model rats, which is different from LA.

[Regulative mechanisms of oxidative stress in kidney in diabetic nephropathy and interventional effects of Chinese herbal medicine].

In the development of diabetic nephropathy (DN), reactive oxygen specie (ROS) over much in vivo leads to oxidative stress(OS)-related renal injuries, which are characterized by the structural and functional changes in glomerular and renal tubular cells in morphology. The regulative approaches of OS involve the several signaling pathways, in which, both p38 mitogen-activated protein kinase (MAPK) signaling pathway and adenosine monophosphate-activated protein kinase (AMPK) signaling pathway play the important roles as the target of anti-oxidants. The interventional actions of Chinese herbal compound prescriptions and the extracts of single Chinese herbal medicine (CHM) on OS in the kidney in DN include regulating the balance between ROS and antioxidants, reducing the production of AGEs, inhibiting the expression of growth factors and intervening the activity of signaling pathways.

Low-dose of multi-glycoside of Tripterygium wilfordii Hook. f., a natural regulator of TGF-ß1/Smad signaling activity improves adriamycin-induced glomerulosclerosis in vivo.

ETHNOPHARMACOLOGICAL RELEVANCE: Transforming growth factor (TGF)-ß1/Smad signaling pathway plays a critical role in the prolonged glomerulosclerosis (GS), which is an important determinant during the progression in chronic kidney disease (CKD). For recent 30 years, multi-glycoside of Tripterygium wilfordii Hook. f. (GTW), an extract from Chinese herbal medicine has been proved clinically effective in improving GS in CKD in China. However, therapeutic mechanisms involved in vivo are still unclear. In this study, we aimed to explain the dose-effects and molecular mechanisms of GTW on GS by regulating TGF-ß1/Smad signaling activity in adriamycin (ADR)-induced nephropathy (ADRN). MATERIALS AND METHODS: Rats with ADRN, created by unilateral nephrectomy and twice adriamycin injections (ADR, 4 mg/kg and 2 mg/kg) within 4 weeks, were divided into four groups, the Sham group, the Vehicle group, the low-dose GTW-treated group, and the high-dose GTW-treated group, and that, sacrificed at the end of the 6th week after administration. Proteinuria, blood biochemical parameters, glomerulosclerotic morphological makers, podocyte shape, and nephrin expression were examined, respectively. Protein expressions of key signaling molecules in TGF-ß1/Smad pathway, such as TGF-ß1, Smad3, phosphorylated-Smad2/3 (p-Smad2/3), and Smad7, were also evaluated individually. RESULTS: The results indicated that the characterizations of ADRN involved the typical prolonged GS, a small amount of abnormal proteinuria, and the failing renal function; TGF-ß1/Smad signaling molecules, especially Smad3, p-Smad2/3, and Smad7 were activated in vivo, accompanied by the exasperation of glomerulosclerotic lesion; GTW at high-dose (100 mg/kg) and low-dose (50 mg/kg) could slightly ameliorate the prolonged GS and nephrin expression, furthermore, the anti-proliferative action of GTW at high-dose was superior to that at low-dose, but caused the significant liver injury; in ADRN model rats, protein expressions of TGF-ß1, p-Smad2/3, and Smad7 in the kidneys could be regulated with the treatment of GTW at low-dose. CONCLUSION: This study farther demonstrated that the low-dose of GTW, as a natural regulator in vivo, could effectively and safely ameliorate the prolonged GS in FSGS model, via the potential molecular mechanisms involving the reduction of ECM components and the suppression of TGF-ß1 over-expression, as well as the bidirectional regulation of TGF-ß1/Smad signaling activity.

[Regulative mechanism of renal inflammatory-related p38MAPK signaling pathway in diabetic nephropathy and interventional effects of Chinese herbal medicine].

It is reported, in the process of diabetic nephropathy (DN), inflammatory-related p38 mitogen-activated protein kinase (MAPK) signaling pathway has a close relationship with renal injury. On the one hand,many factors in the upstream including hyperglycemia, abnormal hemodynamics, oxidative stress, and pro-inflammatory cytokines could activate p38MAPK signaling pathway. On the other hand,the activated p38MAPK signaling pathway could lead to renal damage via activating inflammatory cells, inducing the expression of inflammatory mediators, and intervening cytokines production. CHM could intervene p38MAPK signaling pathway through multi-ways, including inhibiting inflammatory cytokines expression, regulating phosphorylated p38MAPK (p-p38MAPK) expression, and reducing fibrogenic factors expression.

[Molecular mechanisms of renal extracellular matrix degradation and interventional effects of Chinese herbal medicine].

The reduction of extracellular matrix (ECM) degradation in kidney is taken as the morphological features and pathological base in renal injury in chronic kidney disease (CKD). ECM degradation is controlled by the catabolic enzyme systems in glomerulus and renal interstitium, in which matrix metalloproteinases (MMPs) play a key role. The expression and activity of MMPs are regulated by the classical pathway, such as the genic transcription, the activation of zymogen, and the specific inhibitor. The previous studies showed that, Uremic Clearance granule, as a representation, and other prescriptions of Chinese herbal medicine, as well as some extracts from Chinese herbal medicine could intervene the pathway of ECM degradation through promoting the degradation of ECM components, affecting the expression of catabolic enzymes, regulating the genetic transcription of MMPs, and inhibiting the relative signaling transduction of MMPs.

Huangkui capsule, an extract from Abelmoschus manihot (L.) medic, ameliorates adriamycin-induced renal inflammation and glomerular injury via inhibiting p38MAPK signaling pathway activity in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Abelmoschus manihot (L.) medic (AM) is a natural medicinal plant used for the treatment of inflammatory diseases in China. Huangkui capsule (HKC), an extract from AM, has been proved clinically effective in improving renal inflammation and glomerular injury in chronic kidney disease (CKD). However, the dose-effects and the mechanisms involved in vivo are still unclear. AIM OF THE STUDY: This study was performed to examine the dose-effects of HKC on renal inflammation and glomerular lesion in adriamycin-induced nephropathy (ADRN), then to clarify the mechanisms in vivo of HKC by investigating its actions on modulating the activation of p38 mitogen-activated protein kinase (p38MAPK) signaling pathway. MATERIALS AND METHODS: The rats with chronic ADRN, created by the unilateral nephrectomy and twice adriamycin injections (ADR, 4 mg/kg and 2mg/kg) within 4 weeks, were divided into four groups, a Sham group, a Vehicle group, a high-dose HKC group, and a low-dose HKC group, and that, sacrificed at the end of the 4th week after the administration. The rat's general status, renal morphological appearance, proteinuria, blood biochemical parameters, glomerular morphological changes, podocyte shape, and macrophage (ED1(+) and ED3(+) cells) infiltration in glomeruli were examined, respectively. The protein expressions of inflammatory cytokines including tumor necrosis factor (TNF)-α and interleukin (IL)-2, as well as p38MAPK signaling molecules such as transforming growth factor (TGF)-ß1, p38MAPK, and phosphorylated-p38MAPK (p-p38MAPK), were also evaluated individually. RESULTS: HKC at high dose of 2g/kg/d not only significantly ameliorated the rat's general status, renal morphological appearance, proteinuria, albumin, and glomerulosclerosis, but also obviously reduced the infiltrated ED1(+) and ED3(+) macrophages in glomeruli and TNF-α protein expression in the kidney, in addition to these, evidently down-regulated TGF-ß1 and p-p38MAPK protein expressions in ADRN rats, but had no influence on podocyte shape and renal function. CONCLUSION: HKC could dose-dependently ameliorate renal inflammation and glomerular injury in ADRN rats, by way of reducing the infiltration and the activation of macrophages in glomeruli, and TNF-α protein expression in the kidney, as well as inhibiting p38MAPK signaling pathway activity via the down-regulation of p-p38MAPK and TGF-ß1 protein expressions in vivo.

[Overview research of uremic ulearance granule treating chronic renal failure].

The effective bioactivity compositions of uremic clearance granul (UCG) include isoflavonoids, emodin, astragaloside, paeoniflorin, salvianolic acid A, and so on. The effects of UCG treating chronic renal failure (CRF) in clinical pharmacodynamics mainly refer to improve renal function and the complications of CRF. The mechanisms involved in vivo basically include depressing transforming growth factor (TGF)-beta1 over-expression, lessening podocyte injury,inhibiting tubular epithelial myofibroblast transdifferentiation, ameliorating microinflammation status, retarding oxidative stress, and alleviating insulin resistance.

[Effects of huangkui capsule on renal inflammatory injury by intervening p38MAPK signaling pathway in rats with adriamycin-induced nephropathy].

OBJECTIVE: To explore the potential mechanisms of huangkui capsule (HKC), an extract from Abelmoschus manihot (AM), for ameliorating renal inflammatory injury by regulating p38 mitogen-activated protein kinase (MAPK) signaling pathway in rats with adriamycin-induced nephropathy (ADRN). METHOD: Nineteen Sprague-Dawley (SD) rats were randomly divided into three groups, the sham-operation group, the untreated model group,and the HKC-treated group. Rats in the untreated model group and the HKC-treated group were made into ADRN model by right nephrectomy and twice intravenous injections of adriamycin( ADR, 0.4 mL and 0.2 mL respectively within 4 weeks). After the model successfully established, rats in the HKC-treated group were orally given HKC (2 mg x kg(-1) per day), while rats in the untreated model group and the sham-operation group were intervened with distilled water respectively. The intervention for all rats was 4 weeks. Rats' body weight were weighted and 24 h urinary protein excretion (Upro) was detected at the end of the 1st, 2nd, 3rd, and 4th week after the intervention of HKC or distilled water. All rats were sacrificed at the end of the 8th week after nephrectomy, and then, to withdraw blood and kidney to examine the blood biochemical parameters, the glomerular morphological changes, alpha-smooth muscle actin (alpha-SMA) and collagen type I expressions,and the glomerular macrophages infiltration. Besides, the protein expression of transforming growth factor (TGF)-beta1, p38MAPK, as well as phosphorylated p38MAPK (p-p38MAPK) in renal tissues were detected by Western blotting. RESULT: As compared with rats in the untreated model group, in the HKC-treated group,the HKC treatment significantly improved Upro, serum albumin, mesangial cell proliferation, extracellular matrix (ECM) and collagen deposition,and decreased the expression of alpha-SMA and collagen type I and the infiltration of ED1+ and ED3+ cells in glomeruli. In addition, it significantly down-regulated the protein expression of TGF-beta1 and p-p38MAPK in renal tissues. CONCLUSION: HKC had the effects on ameliorating renal inflammatory injury in vivo. It could reduce the expression of TGF-beta1 and improve the infiltration and activation of inflammatory cells in glomeruli by way of intervening p38MAPK signaling pathway in kidney through down-regulating the protein expression of p-p38MAPK, as the key signal molecule.