Fuzheng Huayu recipe and vitamin E reverse renal interstitial fibrosis through counteracting TGF-β1-induced epithelial-to-mesenchymal transition

Aim

To investigate the mechanism of action of Fuzheng Huayu recipe (FZHY) and vitamin E (Vit E) against renal interstitial fibrosis related to transforming growth factor-beta1 (TGF-β1) mediated tubular epithelial-to-mesenchymal transition.

Materials and methods

Renal interstitial fibrosis was induced by administration of HgCl₂ at a dose of 8 mg/kg body weight once a day for 9 weeks. Rats were randomly divided into four groups: normal, model, FZHY, and Vit E group. Rats in the latter two groups were treated with the FZHY recipe and Vit E respectively. HK-2 cells were treated with TGF-β1 for 24 h, followed by incubation with either SB-431542 (a potent and specific inhibitor of TβR-I kinase) or FZHY drug-containing serum for another 24 h. Hyp content in rat kidney tissue was assayed with Jamall's method and collagen deposition in kidney was visualized using Masson stain. Protein expression of TGF-β1, TβR-I, Smad2, p-Smad2, Smad3, and p-Smad3 was analyzed by Western blotting. Protein expression and the location of Smad3 in kidney was assayed by immunohistochemistry, E-cadherin, cytokeratin 18 (CK-18), α-SMA and TGF-β1 by immunofluorescent stain.

Results

FZHY and Vit E inhibited renal collagen deposition and reduced Hyp content significantly. They upregulated E-cadherin protein expression and down-regulated the protein expression of α-SMA, TGF-β1, p-Smad2, p-Smad3, and TβR-I. Lastly, they inhibited the nuclear translocation of Smad3 in fibrotic kidney tissue. FZHY drug-containing serum significantly upregulated the expression of CK-18 and down-regulated the expression of α-SMA, TβR-I, p-Smad2/3 in TGF-β1 stimulated HK-2 cells.

Conclusion

The mechanism of action of FZHY and Vit E against renal interstitial fibrosis is related to the reversal of tubular EMT induced by TGF-β1.     

Paeoniflorin,the main active constituent of Paeonia lactiflora roots,attenuates bleomycin-induced pulmonary fibrosis in mice by suppressing the synthesis of type I collagen

Ethnopharmacological relevance

In the theory of traditional Chinese medicine, pulmonary fibrosis (PF) belongs to pulmonary arthralgia, which means blood stasis in lung tissue. The roots of Paeonia lactiflora Pall are usually used to relieve the symptoms of this disease by promoting blood circulation and removing blood stasis. Paeoniflorin, the main active ingredient of P. lactiflora, may have anti-PF potential.

Aim of study

This study aimed to investigate the effects and underlying mechanisms of paeoniflorin on bleomycin (BLM)-induced PF in mice.

Materials and Methods

The PF model was established in mice by an intratracheal instillation of BLM. Paeoniflorin (25, 50, 100 mg/kg) and prednisone (6 mg/kg), as a positive control, were orally administered for consecutive 21 days. Histopathological changes were evaluated by hematoxylin and eosin stain and Masson's trichrome stain. The content of hydroxyproline was detected by using kits. The contents of type I collagen, TGF-β1 and IFN-γ were detected by ELISA. The levels of α-SMA, Smad4, Smad7 and the phosphorylations of Smad2/3 were detected by western blot. The mRNA expressions of MMP-1 and TIMP-1 were detected by RT-PCR.

Results

In mice treated with BLM, paeoniflorin (50 mg/kg) significantly prolonged the survival periods, attenuated infiltration of inflammatory cells, interstitial fibrosis, and deposition of extracellular matrix in lung tissues. It also decreased the contents of hydroxyproline (a marker of collagens), type I collagen and α-SMA (an indicator of myofibroblasts) in lung tissues of mice. Paeoniflorin down-regulated the expressions of TGF-β1, Smad4 and the phosphorylations of Smad2/3, while up-regulated the expression of Smad7 in lung tissues. Moreover, paeoniflorin increased the content of IFN-γ. But, it only slightly affected mRNA expressions of MMP-1 and TIMP-1 in lung tissues of mice.

Conclusions

Paeoniflorin attenuates PF by suppressing type I collagen synthesis via inhibiting the activation of TGF-β/Smad pathway and increasing the expression of IFN-γ.     

Low-dose of multi-glycoside of Tripterygium wilfordii Hook. f., a natural regulator of TGF-β1/Smad signaling activity improves adriamycin-induced glomerulosclerosis in vivo

Ethnopharmacological relevance

Transforming growth factor (TGF)-β1/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-β1/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-β1/Smad pathway, such as TGF-β1, 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-β1/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-β1, 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-β1 over-expression, as well as the bidirectional regulation of TGF-β1/Smad signaling activity.     

Effect of Tangnaikang on TGF-β1-induced transdifferentiation of human renal tubular epithelial HK-2 cells

Objective

To explore the function of Tangnaikang (TNK) in the prevention and treatment of renal interstitial fibrosis through transdifferentiation of the human renal tubular epithelial cell line HK-2 induced by transforming growth factor-β₁ (TGF-β₁).

Methods

HK-2 cells cultured in dulbecco's modified eagle medium/F12 (1:1) with 10% fetal calf serum were divided into six groups: blank control group, TGF-β₁ group (TGF-β₁ 10 ng/mL), serum control group (TGF-β₁ 10 ng/mL + 10% serum), treatment group 1 (TGF-β₁ 10 ng/mL + 5% TNK serum), treatment group 2 (TGF-β₁ 10 ng/mL + 10% TNK serum), and treatment group 3 (TGF-β₁ 10 ng/mL + 20% TNK serum). Cell proliferation was detected by 4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Expression of α-smooth muscle actin (α-SMA) and E-cadherin were observed by immunohistochemical assay. The contents of collagen I (Col I), collagen III (Col III), and fibronectin (FN) in the culture medium supernatant were detected by ELISA.

Results

E-cadherin was expressed and α-SMA was not expressed in normal HK-2 cells. In HK-2 cells cultured with TGF-β₁ α-SMA expression significantly increased, HK-2 cells significantly proliferated, and secretion of Col I, Col III, and FN significantly increased compared with the blank control group (all P<0.05). In the HK-2 cells cultured with TGF-β₁ and TNK serum, the expression of α-SMA significantly decreased, the expression of E-cadherin significantly increased, and the cell proliferation and the secretion of Col I, Col III and FN were significantly inhibited compared with the TGF-β₁ group (all P<0.05).

Conclusion

TNK can inhibit cell proliferation and reduce secretion of Col I, Col III, and FN. This indicates that TNK can inhibit transdifferentiation of human renal tubular epithelial cells induced by TGF-β₁, with the effect of preventing and treating renal interstitial fibrosis.     

Effect of bioactive peptide of Carapax Trionycis on TGF-β1-induced intracellular events in hepatic stellate cells

Ethnopharmacological relevance

In traditional Chinese medicines for hepatic fibrosis therapy, Carapax Trionycis is used usually as an indispensable component and has a long history of medical use in China. Previous studies have demonstrated that extracts of Carapax Trionycis were able to protect liver against fibrosis in CCl₄ animal models.

Aim of the study

The purpose of this study is to verify the inhibitory effect and the underlying mechanisms of Carapax Trionycis extract peptide (CTEP) on activated hepatic stellate cells which play a central role in liver fibrogenesis.

Materials and methods

Hepatic stellate cells induced by TGF-β₁ were applied to evaluate the anti-fibrotic effect of CTEP in vitro. MTS assay, enzyme-linked immunosorbent assay and western blotting were then used to further investigate the molecular mechanisms.

Results

The results show that the contents of collagen I, collagen III and TIMP-1 were significantly inhibited and the level of collagen I, collagen III, p-Smad 3, TIMP-1 and α-SMA proteins decreased significantly in a concentration-dependence manner after treatment with CTEP. Interestingly, the level of Smad 3 protein was not different significantly.

Conclusions

Our data indicate that CTEP efficiently inhibits cultured HSC-T₆ cell activation and proliferation via the TGF-β₁/Smad pathway as well as by the elimination of the extracellular matrix.     

Effect of Astragali-Cordyceps Mixtura on TGF-β/Smad signal pathway in the lung of asthma airway remodeling

Aim of the study

We try to find out the influence of traditional Chinese Medicine Astragali-Cordyceps Mixtura (ACM) on TGF-β/Smad signal pathway in the lung of asthma airway remodeling.

Materials and methods

Mice were sensitized and challenged by OVA to establish a model of asthma. To assess the effects of ACM on the mice, animals of the ACM groups were treated with ACM. Data were achieved by using techniques as follow: counting cell number of BALF, assaying the amount of collagen deposition by Masson's staining, performing RT-PCR and immunohistochemistry for mRNA and protein expression of TGF-β1, Smad3 and Smad7.

Results

The depositions of collagen in airway wall greatly increased at the model group compared with that of the normal group. In contrast, these decreased at the ACM groups. As compared with the control group, TGF-β1 expression also decreased at both mRNA and protein level at the ACM-M group versus increased both at the model group. Whereas, Smad7 significantly decreased only at the model group and partly restored at the ACM-M group.

Conclusions

ACM greatly improves the symptoms of asthma airway remodeling by inhibiting the expression of TGF-β1 and upregulating the amount of Smad7.     

Ojeok-san,a traditional Korean herbal medicine attenuates airway inflammation and pulmonary fibrosis induced by repeated ovalbumin challenge

Ethnopharmacological evidence

Ojeok-san, a traditional Korean herbal medicine, is widely used in China, Japan and Korea for treatment of the common cold, pain and fever.

Aim of the study

In this study, we investigated the protective effects of Ojeok-san aqueous extract (OJS) against pulmonary fibrosis using a chronic asthma murine model.

Methods

Mice were sensitized by intraperitoneal injection of ovalbumin (OVA), followed 1 weeks later by an airway challenge with OVA delivered three times a week for 4 weeks. OJS (50 mg/kg or 100 mg/kg) was also administered by oral gavage once a day for 4 weeks.

Results

OJS significantly reduced interleukin (IL)-4, IL-13, eotaxin, immunoglobulin E and the number of inflammatory cells in bronchoalveolar lavage fluid; in addition, it reduced inflammatory cell infiltration and mucus production in the respiratory tract. We found that OJS also attenuated the OVA-induced increase in vascular endothelial growth factor (VEGF), transforming growth factor (TGF)-β₁ and Smad3 protein in lung tissue, as determined by Western analysis and immunohistochemistry. These inhibitory effects of OJS were accompanied by a reduction in pulmonary fibrosis, consistent with the histopathology of lung tissue stained with Masson's trichrome.

Conclusion

Administration of OJS reduced the airway inflammation and pulmonary fibrosis, as well as the level of T helper type 2 cytokines and VEGF and TGF-β₁/Smad3 expressions in lung tissue. These results suggest that OJS might represent a useful new oral therapy for the treatment of chronic asthma.     

Effect and mechanism of methyl helicterate isolated from Helicteres angustifolia (Sterculiaceae) on hepatic fibrosis induced by carbon tetrachloride in rats

Ethnopharmacological relevance

Methyl helicterate is a triterpenoid isolated from Helicteres angustifolia (Sterculiaceae), one of the valuable traditional Chinese herbs. Antifibrotic activities of H. angustifolia have been extensively proved.

Aim of the study

The purpose of this study was to investigate the effect of methyl helicterate (MH) on liver fibrosis in rats induced by carbon tetrachloride (CCl₄) and to explore its underlying mechanism.

Materials and methods

Hepatic fibrosis was induced in male Sprague–Dawley (SD) rats by intragastric administration with 2 ml/kg CCl₄ (mixed 1:1 in peanut oil) twice a week for 12 weeks. To evaluate the effect of MH (16.72, 33.45, 66.90 mg/kg) on hepatic fibrosis, liver function, histological study and hepatic fibrosis evaluation were performed. Liver function was assessed by determining the serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin (Alb) and total protein (TP). The biomarkers such as hydroxyproline (Hyp), hyaluronic acid (HA), type III precollagen (PCIII) and laminin (LN) were examined for the evaluation of hepatic fibrosis. The underlying mechanism was investigated by measuring oxidative stress level and detecting the expression of TGF-β1 mRNA and Smad3 protein.

Results

MH (33.45, 66.90 mg/kg) treatment significantly inhibited the loss of body weight and the increase of liver index in rats induced by CCl₄. MH also improved the liver function as indicated by decreasing serum enzymatic activities of ALT, AST, TP and Alb (P<0.05). Histological results indicated that MH alleviated liver damage and reduced the formation of fibrous septa. Moreover, MH significantly decreased liver Hyp, HA, LN and PCIII (P<0.05). Research on mechanism showed that MH could markedly reduce liver malondialdehyde (MDA) concentration, increase activities of liver superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and inhibit the expression of TGF-β1 mRNA and Smad3 protein (P<0.05).

Conclusions

Our findings indicated that MH can inhibit CCl₄-induced hepatic fibrosis, which may be ascribed to its radical scavenging action, antioxidant activity, and modulation of TGF-β-Smad3 signaling pathway.     

Effects of Tulbaghia violacea Harv. (Alliaceae) rhizome methanolic extract on kidney function and morphology in Dahl salt-sensitive rats

Ethnopharmacological relevance

Tulbaghia violacea has been used traditionally for the treatment of several ailments, including hypertension. The herb has been shown to have antihypertensive properties which have been attributed to its angiotensin-converting enzymeinhibitory (ACEI) activity. It could, therefore, prove beneficial in ameliorating renal pathology associated with hypertension. To evaluate the effects of long-term administration of Tulbaghia violacea on renal function and morphology in the Dahl salt-sensitive (DSS) rat model.

Materials and methods

Male DSS rats were treated intra-peritoneally (i.p.) as follows: methanolic extract of Tulbaghia violacea: (TVL) (50 mg/kg/b.w.), captopril: (CAP) (25 mg/kg/b.w.), or distilled water, control: (CON) (3 ml/kg/b.w.). Blood pressure (BP) was measured bi-weekly, whilst 24-h urine volumes and electrolyte concentrations were assessed weekly. Animals were sacrificed on day 49 by halothane overdose. Blood was removed for determination of plasma and serum electrolytes. Left kidney tissues were harvested for the determination of nuclear factor-kappaβ (NF-kβ) and transforming growth factor-β (TGF-β) gene expressions.

Results

TVL significantly reduced mean arterial pressure (MAP) and diastolic blood pressure (DBP). TVL showed reduced blood urea nitrogen, serum creatinine, total protein in urine as well as increased serum total protein. TVL decreased thiobarbituric acid reactive substances (TBARS) and increased glutathione peroxidase (GPx) and superoxide dismutase (SOD) activity and nitric oxide significantly. NF-kβ and TGF-β) gene expressions were significantly reduced in TVL and CAP treated rats. Moreover, renal morphology improved significantly in TVL and CAP treated animals.

Conclusion

TVL and CAP demonstrated marked improvement in renal function and morphology.     

Therapeutic potential of intravenous Xuebijing on transforming growth factor β1 and procollagen type Ⅲ peptide in patients with acute paraquat poisoning

Objective

Paraquat (PQ) poisoning-induced pulmonary fibrosis causes asphyxiation and death. The therapeutic potential of intravenous Xuebijing therapy in PQ poisoning patients and its underlying immunomodulatory effects on transforming growth factor (TGF)-β₁, and procollagen type III peptide (PIIIP) were investigated.

Methods

Thirty-six acute PQ poisoning patients were randomly assigned to conventional therapy (Group A) and intravenous Xuebijing administration plus conventional therapy (Group B). Twenty volunteers served as controls (Group C). Blood samples were collected upon admission (day 0) and at post-treatment days 5, 10, and 14. TGF-β₁ and PIIIP concentrations were determined by ELISA and analyzed for intra- and inter-group differences over time. One-month follow-up was conducted for determining the mortality rate.

Results

TGF-β₁, and PIIIP levels were significantly higher in PQ poisoning patients and increased over time (Groups A and B vs C, P<0.01). However, the TGF-β₁ and PIIIP levels were consistently significantly lower in Group B compared with those of Group A (P<0.01). The 1-month mortality rate was also lower in Group B compared with that of Group A (P<0.05). PQ poisoning patients showed remarkably high levels of TGF-β₁ and PIIIP, which increased as PQ-induced pulmonary fibrosis progressed.

Conclusion

Treatment with intravenous Xuebijing plus conventional therapy significantly lowered TGF-β₁ and PIIIP levels, which indicates therapeutic efficacy in the treatment of PQ poisoning patients.     

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.     

18β-Glycyrrhetinic acid potently inhibits Kv1.3 potassium channels and T cell activation in human Jurkat T cells

Ethnopharmacological relevance

Licorice has been extensively used in traditional medicines for treatment of many diseases, including inflammations and immunological disorders. Recent studies have shown that the anti-inflammatory and immunomodulation activities of licorice have been attributed to its active component, glycyrretinic acid (GA). GA consists of two isoforms, 18α- and 18β-. However, its mechanism remains poorly understood.

Aim of the study

We compared the effects of two isoforms on Kv1.3 channels in Jurkat T cells and further characterized the inhibition of Kv1.3 channels by 18β-GA in CHO cells. In addition, we examined the effects of 18β-GA on Kv1.3 gene expression, Ca²⁺ influx, proliferation, as well as IL-2 production in Jurkat T cells.

Materials and methods

Whole-cell patch-clamp technique was applied to record Kv1.3 currents in Jurkat T or CHO cells. Real-time PCR and Western blotting were used to detect gene expression. Fluo-4, CCK-8 kit and ELISA kit were used to measure Ca²⁺ influx, proliferation, and IL-2 secretion in Jurkat T cells, respectively.

Results

Superfusion of 18β-GA (10–100 µM) blocked Kv1.3 currents in Jurkat T cells, while 18α-GA at the same concentration had no effect. The 18β-GA induced inhibition had a voltage- and concentration-dependent manner with an IC₅₀ of 23.9±1.5 µM at +40 mV in CHO cells. Furthermore, 18β-GA significantly inhibited Kv1.3 gene expression. In addition, paralleling Kv1.3 inhibition, 18β-GA also inhibited Ca²⁺ influx, proliferation as well as IL-2 production in Jurkat T cells.

Conclusion

18β-GA blocks Kv1.3 channels, which probably involves its anti-inflammatory and immunomodulation effects.     

Protection of glycyrrhizic acid against AGEs-induced endothelial dysfunction through inhibiting RAGE/NF-κB pathway activation in human umbilical vein endothelial cells

Ethnopharmacological relevance

Licorice (Glycyrrhiza uralensis roots) is used as a traditional medicine for the treatment of diabetes mellitus and its vascular complications. Glycyrrhizic acid (GA, also known as Glycyrrhizin), a triterpenoid saponin glycoside, is considered to be a bioactive component in Licorice and is beneficial to diabetic vascular complications.

Aim of study

The present study was conducted to evaluate the potential protective activities on AGEs-induced endothelial dysfunction, including anti-apoptosis, antioxidant stress and anti-proinflammatory responses, and explore the underlying mechanism.

Materials and methods

Human umbilical vein endothelial cells (HUVECs) were incubated and pre-treated with GA (10⁻⁹–10⁻⁶ M) or RAGE-Ab (5 μg/ml) in the presence or absence of 200 μg/ml AGEs. AO/EB fluorescence staining assay was performed to evaluate anti-apoptosis activity. The superoxide dismutase (SOD) activity and malondialdehyde (MDA) level in cell supernatant were detected by kits while the intracellular reactive oxygen species (ROS) generation was determined by 2,7-dichlorodihydrofluorescin diacetate (DCFH-DA) kit. Immunocytochemistry analysis was designed to determine transforming growth factor beta1(TGF-β1) protein expression while immunofluorescence analysis for RAGE and NF-kB. The protein expressions of TGF-β1, RAGE and NF-kB were analyzed by Western blot analysis.

Results

Pretreatment with GA at a concentration of 10⁻⁸–10⁻⁶ M significantly reduced the AGEs-induced apoptosis in HUVECs. GA significantly increased antioxidant enzyme SOD activity and decreased peroxide degradation product MDA level in a dose-dependent manner. Furthermore, GA also remarkably inhibited the overgeneration of AGEs-induced ROS. Both immunocytochemistry analysis and western blot analysis showed that GA significantly decreased the protein expression of poinflammatory cytokine TGF-β1 in a similar manner which RAGE-Ab did. Additionally, AGEs-induced RAGE and NF-kB protein expressions were down-regulated significantly by the pretreatment with GA or RAGE-Ab.

Conclusion

These findings provide evidences that GA possesses protective activity on AGEs-induced endothelial dysfunction, including anti-apoptosis, anti-inflammation and antioxidant stress, via inhibiting RAGE/NF-kB pathway. GA might be an alternative for the prevention and treatment of diabetic vascular complications in an appropriate dosage.     

Schisandrin B suppresses TGFβ1-induced stress fiber formation by inhibiting myosin light chain phosphorylation

Ethnopharmacological relevance

Schisandra chinensis fruit extract (SCE) has been used as a traditional oriental medicine for treating vascular diseases. However, the pharmacologic effects and mechanisms of SCE on vascular fibrosis are still largely unknown. Transforming growth factor β1 (TGFβ1)-mediated cellular changes are closely associated with the pathogenesis of vascular fibrotic diseases. Particularly, TGFβ1 induces actin stress fiber formation that is a crucial mechanism underlying vascular smooth muscle cell (VSMC) migration in response to vascular injury. In this study, we investigated the effect of SCE and its active ingredients on TGFβ1-induced stress fiber assembly in A7r5 VSMCs.

Materials and methods

To investigate pharmacological actions of SCE and its ingredients on TGFβ1-treated VSMCs, we have employed molecular and cell biological technologies, such as confocal microscopy, fluorescence resonance energy transfer, western blotting, and radiometric enzyme analyses.

Results

We found that SCE inhibited TGFβ1-induced stress fiber formation and cell migration. Schisandrin B (SchB) showed the most prominent effect among the active ingredients of SCE tested. SchB reduced TGFβ1-mediated phosphorylation of myosin light chain, and this effect was independent of RhoA/Rho-associated kinase pathway. Fluorescence resonance energy transfer and radiometric enzyme assays confirmed that SchB inhibited myosin light chain kinase activity. We also showed that SchB decreased TGFβ1-mediated induction of α-smooth muscle actin by inhibiting Smad signaling.

Conclusions

The present study demonstrates that SCE and its active ingredient SchB suppressed TGFβ1-induced stress fiber formation at the molecular level. Therefore, our findings may help future investigations to develop multi-targeted therapeutic strategies that attenuate VSMC migration and vascular fibrosis.     

The anti-inflammation effect of Moutan Cortex on advanced glycation end products-induced rat mesangial cells dysfunction and High-glucose–fat diet and streptozotocin-induced diabetic nephropathy rats

Ethnopharmacological relevance

Moutan Cortex (MC, family: Paeonia suffruticosa Andr.) is a well-known traditional herbal medicine that has been shown to hold a protective effect on inflammation in several diseases. However, its anti-inflammatory activity on diabetic nephropathy (DN) has been less reported. The present study was conducted to evaluate the potential attenuation activities of MC on inflammation in AGEs-induced rat mesangial cells dysfunction and high-glucose–fat diet and streptozotocin (STZ)-induced DN rats and explore the possible mechanism underlying its DN effect.

Materials and methods

The inflammation in mesangial cells (HBZY-1) was induced by 200 μg/ml advanced glycation end products (AGEs). DN rats model was established by an administration high-glucose–fat diet and an intraperitoneal injection of STZ (30 mg/kg). Interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1) level in cell supernatant and rats serum were detected by appropriate kits. A co-culture system of mesangial cells and macrophages was performed to evaluate the migration of macrophages. Immunohistochemical assay was applied to examine transforming growth factor beta1 (TGF-β1), IL-6, MCP-1 and intercellular adhesion molecule-1 (ICAM-1) expression in kidney tissues of rats. Furthermore, western blot analysis was carried out to examine TGF-β1, IL-6, MCP-1, ICAM-1 and RAGE protein expressions in mesangial cells.

Results

Pretreatment with MC could significantly inhibit AGEs-induced migration of macrophages in the co-culture system of mesangial cell and macrophage. MC could decrease IL-6 and MCP-1 levels in serum of DN rats in a dose-dependent manner. Furthermore, MC also improved the blood glucose, serum creatinine and urine protein levels. Both immunocytochemistry analysis and western blot analysis showed that MC decreased significantly the over-expression of IL-6, MCP-1, TGF-β1, ICAM-1 and RAGE in mesangial cells or kidney tissues. Additionally, the protein expression of proinflammatory cytokine could also be down-regulated by the pretreatment of RAGE-Ab (5 μg/ml).

Conclusion

These findings indicated that the extract of MC had an amelioration activity on the inflammation in AGEs-induced mesangial cells dysfunction and high-glucose–fat diet and STZ-induced DN rats. The protective effect might be associated with the intervention of MC via target of RAGE. These findings suggested that MC might be a benefit agent for the prevention and treatment of DN.     

Aqueous extract of Taxus Chinensis (Pilger) Rehd inhibits lung carcinoma A549 cells through the epidermal growth factor receptor/mitogen-activated protein kinase pathway in vitro and in vivo

Objective

To explore the anticancer mechanism of aqueous extract of Taxus Chinensis (Pilger) Rehd (AETC).

Methods

The serum pharmacological method was used to avoid interference from administration of the crude medicinal herbs. Eight purebred New Zealand rabbits were used for preparation of serum containing various concentrations of AETC. Forty-eight Balb/c-nu mice were used for in vivo experiments. The effects of serum containing AETC on the proliferation of A549 cells and expression levels of the epidermal growth factor receptor/mitogen-activated protein kinase (EGFR/MAPK) pathway-related proteins in vitro were investigated. Additionally, the effects on the growth of A549 xenografts in nude mice, and expression levels of the EGFR/MAPK pathway-related proteins in the xenografts, were investigated.

Results

3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay revealed that the serum containing AETC significantly decreased the viability of A549 cells in a dose-dependent manner. Western blot showed that the serum containing various concentrations of AETC strongly reduced the levels of phospho-Jun N-terminal kinase (p-JNK) and phospho-extracellular signal-regulated kinasel/2 (ERK1/2) while it increased the level of p-p38. However, no significant effects on the expression levels of JNK, ERK1/2, and p38 MAPK were found. In addition, an anticancer effect from AETC was observed in vivo in the Balb/c-nu mice bearing A549 xenografts.

Conclusion

AETC has significant effects on the growth of A549 xenografts and on the activity of the EGFR/MAPK pathway. Therefore, AETC may be beneficial in lung carcinoma treatment.     

KIOM-79 prevents S100b-induced TGF-β1 and fibronectin expression in mouse mesangial cells

Aim of the study

In this study, we investigated whether KIOM-79 inhibits transforming growth factor-beta 1 (TGF-β1) and fibronectin expression in mouse mesangial cells cultured under S100b, a specific ligand of the receptor for advanced glycation end products (RAGE).

Materials and methods

Cell counting kit (CCK-8) assay was employed to evaluate the viability of KIOM-79-treated mesangial cells. The effect of KIOM-79 on S100b-induced TGF-β1 and fibronectin expression was investigated using RT-PCR, ELISA, and Western blot on mesangial cells.

Results

KIOM-79 (up to 50 μg/ml) appeared to have no effect on cell viability. S100b induced an increase in the expression TGF-β1 and fibronectin. Expression of TGF-β1 and fibronectin was inhibited significantly by KIOM-79 treatment in mesangial cells. KIOM-79 also inhibited the expression of NF-kB and inactivated p38 mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinase (ERK) 1/2 in mesangial cells. KIOM-79 pretreatment inhibited increased malondialdehyde (a product of lipid peroxidation and a marker for oxidative stress) levels in S100b-induced mesangial cells.

Conclusions

These data demonstrate that KIOM-79 inhibits expression of TGF-β1 and fibronectin through inactivation of MAPK/ERK1/2 signaling, reduction in malondiadehyde levels, and inhibition of NF-kB in mesangial cells cultured under diabetic conditions. KIOM-79 could be beneficial for preventing of the development of diabetic complications such as nephropathy.     

In vitro screening on amyloid precursor protein modulation of plants used in Ayurvedic and traditional Chinese medicine for memory improvement

Ethnopharmacological relevance

The 15 herbs for the screening have been traditionally used in Ayurvedic medicine or in Traditional Chinese medicine (TCM) for the treatment of cognitive disorders clinically.

Aim of the study

Fifteen plant species were investigated for the inhibition of amyloid peptide (Aβ) production and modulation of amyloid precursor protein (APP) processing.

Materials and methods

The selected plants were extracted successively with 70% ethyl alcohol and absolute alcohol concentrated with rotary evaporation then lyophilized. Using a mouse neuroblastoma cells expressing Swedish APP (N2a-SweAPP), MTT assay was performed to determine the toxicity concentration of each herbal extract. In order to evaluate the activity of ethanol extracts on Aβ inhibition, the N2a-SweAPP cells were treated with a high and low dosage of different extracts for 24 h, Aβs levels in the supernatant of conditioned media were assessed by ELISA. The most active extracts were then subjected to test the effect on APP modulation in N2a-SweAPP cells by determining their effect on sAPPα and sAPPβ through western blot analysis.

Results

Among the screened herbal extracts, only Polygonum multiflorum Thunb. (root) and Convolvulus pluricaulis Choisy. (leaves) showed profound inhibition of Aβ production. MTT assay demonstrated that the anti-Aβ effect of these extracts was not a sequential consequence of their cytotoxicity. The extract of Polygonum multiflorum Thunb. (root) could reduce Aβ production only through APP modulation, which was exhibited together with the up-regulation of sAPPα and down-regulation of sAPPβ.

Conclusion

The results show that extract of Polygonum multiflorum Thunb. (root) can lower Aβ generation by modulating APP processing in the N2a-SwedAPP cell line. These results corroborate the traditional use of Polygonum multiflorum Thunb. (root) for the treatment of cognitive disorders including Alzheimer's disease (AD).