Effect of Shenxinning decoction on ventricular remodeling in AT1 receptor-knockout mice with chronic renal insufficiency,Xuejun Yang1, Hua Zhou1, Huiyan Qu1, Weifang Liu2, Xiaojin Huang2, Yating Shun2, Liqun He1, : Indian Journal of Pharmacology

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RESEARCH ARTICLE	[Download PDF]

Year : 2014 \| Volume : 46 \| Issue : 4 \| Page : 391--397

Effect of Shenxinning decoction on ventricular remodeling in AT1 receptor-knockout mice with chronic renal insufficiency

Xuejun Yang¹, Hua Zhou¹, Huiyan Qu¹, Weifang Liu², Xiaojin Huang², Yating Shun², Liqun He¹,
¹ Institute of Kidney Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, China
² Shanghai University of Traditional Chinese Medicine, Shanghai, China

Correspondence Address:
Hua Zhou
Institute of Kidney Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai
China

Abstract

Objective: To observe the efficacy of Shenxinning Decoction (SXND) in ventricular remodeling in AT1 receptor-knockout (AT1-KO) mice with chronic renal insufficiency (CRI). Materials and Methods: AT1-KO mice modeled with subtotal (5/6) nephrectomy were intervened with SXND for 12 weeks. Subsequently, blood urea nitrogen (BUN), serum creatinine (SCr), brain natriuretic peptide (BNP), echocardiography (left ventricular end-diastolic diameter, LVDD; left ventricular end-systolic diameter, LVDS; fractional shortening, FS; and ejection fraction, EF), collagen types I and III in the heart and kidney, myocardial mitochondria, and cardiac transforming growth factor-β1 (TGF-β1) of the AT1-KO mice were compared with the same model with nephrectomy only and untreated with SXND. Results: AT1-KO mice did not affect the process of CRI but it could significantly affect cardiac remodeling process. SXND decreased to some extent the AT1-KO mice«SQ»s BUN, SCr, BNP, and cardiac LVDD, LVDS, and BNP, improved FS and EF, lowered the expression of collagen type I and III in heart and kidney, increased the quantity of mitochondria and ameliorated their structure, and down-regulated the expression of TGF-β1. Conclusion: SXND may antagonize the renin-angiotensin system (RAS) and decrease uremia toxins, thereby ameliorating ventricular remodeling in CRI. Furthermore, SXND has a mechanism correlated with the improvement of myocardial energy metabolism and the down-regulation of TGF-β1.

How to cite this article:
Yang X, Zhou H, Qu H, Liu W, Huang X, Shun Y, He L. Effect of Shenxinning decoction on ventricular remodeling in AT1 receptor-knockout mice with chronic renal insufficiency.Indian J Pharmacol 2014;46:391-397

How to cite this URL:
Yang X, Zhou H, Qu H, Liu W, Huang X, Shun Y, He L. Effect of Shenxinning decoction on ventricular remodeling in AT1 receptor-knockout mice with chronic renal insufficiency. Indian J Pharmacol [serial online] 2014 [cited 2023 Jun 1 ];46:391-397
Available from: https://www.ijp-online.com/text.asp?2014/46/4/391/135950

Full Text

Introduction

Patients with chronic kidney diseases (CKDs) are at high risk of cardiovascular diseases (CVDs), with the incidence rate being approximately five to eight times of that observed in the general population of the same age. The onset age of CVD for these patients has shifted to as early as 30 to 40 years. Various CVDs induced by CKDs in uremia condition share a common pathological characteristic of cardiac remodeling. [1]

Cardiac remodeling in patients with chronic renal insufficiency (CRI) is a pathological change caused by various factors. Its pathogenesis is not exactly the same as that of hypertension or chronic congestive heart failure. Aside from the traditional risk factors, non-traditional factors also play a role in inducing CVDs in CKD patients. CKD in patients is generally accompanied by renin-angiotensin system (RAS) activation, [2] hyperhomocystinemia, [3] disorder in calcium-phosphorus metabolism, secondary hyperthyroidism, [4] anemia, [5] oxidative stress, and inflammatory state, [6] along with the progression of renal hypofunction. Previous studies [7] imply the efficacy of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II type 1 receptor blockers (ARBs) in significantly ameliorating cardiac/renal function and in inhibiting both LVH and myocardial fibrosis because of their interference with RAS. However, ACEIs and ARBs cannot effectively inhibit the onset and development of CVD or lower the mortality rate for patients with CRI, given the uniqueness and boundedness of their targets. Therefore, a substitute therapy is needed for patients in the terminal stage.

Shenxinning Decoction (SXND), a traditional Chinese medicine developed for the treatment of cardiac remodeling in CRI, is made from rhubarb, Salvia miltiorrhiza, semen persicae, radix astragali, hartshorn, radix curcumae, and Rhizoma smilacis glabrae. It is assumed to be capable of preventing myocardial hypertrophy, inhibiting collagen hyperplasia, and improving cardiac remodeling to some extent based on our long-term clinical experience and laboratory studies. These studies show that SXND may lower to a certain degree the weight of the myocardium with hypertrophy in rats with CRI and inhibit myocardial remodeling. Myocardial remodeling is characterized as the decrease in cardiac index, left ventricular index, and expression of myocardial collagen. Further studies have concluded that the intervention on ventricular remodeling by SXND results in the lowering of toxins and the amelioration of both anemia and RAS. [8],[9]

Although the efficacy of traditional Chinese medicine is clear, the active mechanism of the medicine is complex. The purpose of this study was to clarify whether SXND played a role by improving the RAS. By using gene technology, angiotensin receptor-knockout mouse model (AT1-KO) was used to completely block the angiotensin receptor 1 in the RAS pathway, which was more effective in blocking RAS activation compared with the use of ARB class of drugs. Thus, the effect of RAS on the disease could be excluded. This method can be used to clarify the action of RAS in cardiac remodeling resulted from chronic renal failure and to elucidate the chief mechanism of SXND in improving cardiac remodeling of CRI, which may be associated with improvement of RAS and lower of CRI toxins.

Materials and Methods

Animals

BL/6 male mice weighing 18-20 g were provided by Shanghai Silaike Experiment Animal Co., Ltd. [License No. SCXK (Hu) 2011-0010]. They were raised in clean feeding rooms in the Breeding Center of Shanghai University of Traditional Chinese Medicine. Intake of water and forage was allowed ad libitum during the experiment.

Vector Construction

The strategy was to knock out an exon to yield a frame-shift mutation. The frame-shift mutation and the premature termination of protein transcription were induced by knocking out the exons positioned in the front for a gene with only one transcript, as far as possible and by knocking out the common exons for a gene with multiple transcripts. The gene region to be knocked out in this research contained one transcript, with its encoding region at the third exon. The mutation was induced, and protein translation was cancelled after the third exon was knocked out. The element of Neo was then inserted into the region between intron 2-3 and the non-encoding region of the third exon [Figure 1]a.{Figure 1}

The primers of A, B, C, and D should be appropriately selected (as the size of the two homologous arms, Southern restriction analysis, and sequencing structural characteristics should be considered, etc.) The primers of A, B, and two small homologous arms (mini-arm), were to be cloned into the plasmid of pBR322-2S retrieve. The design length was 300-500 bp. The primer Bup together with the primer Alow formed a 20-bp overlap; the primers of C and D were cloned into the PL452. The length of the primers was designed to be 200-300 bp (preferably not more than 300 bp). The most commonly used restriction endonuclease that was suitable for southern hybridization included EcoRI, EcoRV, BamHI, HindIII, and BglII.

A and B were first amplified, followed by a second round of polymerase chain reaction (PCR) with a mixture of PCR products from A and B as the substrate to obtain A + B (overlap PCR). A + B was then cloned to HindIII and BamHI of pBR322-2S plasmid, and pBR322-2S-AB was linearized with XhoI. Meanwhile, C and D amplified from BAC were cloned to KpnI/EcoRI of PL452 and BamHI/Not I of PL452, respectively. Subsequently, PL452-CD was enzymatically digested with KpnI/Not I; C-neo-D, the chipped fragments, was recycled for backup.

The monoclone of BAC (bMQ-289f19) was selected and kept overnight at 37°C. On the following day, it was inoculated in 3 ml of fresh LB culture solution at a ratio of 1:50. The cells were incubated at 37°C for 2 h until OD 600 reached approximately 0.4 and then prepared for competence assay. The cells were transformed with pSC101-BAD-γβα-A-tet (ZET1), smeared onto a double-antibody plate (with chloromycetin BAC plus tetracycline ZET10), and then incubated overnight at 30°C.

Retrieved BAC clones (also called gap repair) that had been transformed to ZET1 were selected and kept overnight at 30°C. The clones were inoculated the following day in 3 ml of fresh LB culture solution at a ratio of 1:50, incubated at 30°C for about 2 h with OD 600 controlled within 0.2, added with 10% arabinose to yield a final concentration of 0.1-0.2%, and then incubated at 37°C until OD 600 reached 0.4 upon preparation for competence assay. Linearized pBR322-2S-ab (50-100 ng) was transformed and spiked onto an ampicillin plate and incubated overnight at 37°C. The retrieved plasmid of neo knock-in was transformed into EL-250, spiked onto an ampicillin plate, and incubated overnight at 32°C. One monoclone was chosen, spiked on LB (Amp + ), and kept overnight. On the following day, it was inoculated in 3 ml of fresh LB (Amp + ) at a ratio of 1:50, incubated at 32°C for 2 h until OD 600 reached approximately 0.35 (<0.5 was preferred), and immediately moved to a shaking table for heat shock for 15 min at 42°C. An immediate ice cooling was performed, followed by the preparation for competence assay. The fragments of transformed C-neo-D (200-300 ng) were spiked onto a double-antibody plate of ampicillin plus kanamycin and kept overnight at 32°C.

The plasmids obtained in this study were often a mixture of two plasmids, namely, retrieved and neo knock-in. The right neo knock-in plasmid validated by enzyme digestion was re-transformed into a DH5α competence cell, which was spiked onto an ampicillin or kanamycin plate. During this course, the retrieved plasmids were eliminated, leaving only neo knock-in plasmids. The remaining neo knock-in plasmids underwent further validation through enzyme digestion and sequencing.

Breeding of AT1 Receptor-knockout Mice

A knockout-targeting plasmid was designed according to the structure of a specific gene in the mice genome and the structure of its protein based on previous studies. [10],[11] The knockout-targeting plasmid was constructed and then linearized. Targeting was performed in ES cells originating from 129 mice with gray hair. ES cells underwent G418 positive screening, and ES cells with positive results underwent PCR screening for positive ES cells with both recombinant arms. The positive ES cells were resuscitated and re-checked. After re-checking, the positive ES cells were adopted for blastocyst injection and transplanted into pseudopregnant mice (C57 mice with black hair). The offspring of the C57 mice with black hair was observed, and the chimeric male mice with more than 50% gray hair were those with high-proportion integrated ES cells. The mice with gray hair borne by a C57 female mouse that mated with a chimeric male mouse were those developing from the cell derived from 129 ES cells. Heterozygote mice were obtained by determining the genotype of the gray mice.

CRI Model

Subtotal (5/6) nephrectomy was performed. The mice that were fasted for 12 h prior to surgery were anesthetized with peritoneal injection of 2% pentobarbital sodium and fixed on a surgical table after the corneal reflex disappeared. Hair in the surgical region was shaved. After the abdomen was opened, the left kidney was exposed, and the adipose capsule was peeled. Renal pole was clamped with a serrefine, and two-thirds of the renal cortex was carefully removed to avoid injuring the adrenal gland. Finally, the abdomen was closed following the procedures above. The second laparotomy was performed after one week. The adipose capsule was peeled, and the pole of the right kidney was ligated. Thereafter, the right kidney was removed, and the abdomen was closed. Blood was sampled from the angular vein of the mice to determine serum creatinine (SCr). Modeling was considered a success if P < 0.05 based on a comparison between the model group and normal mice. In the pseudosurgery group, nephrectomy was not carried out but suture was performed layer after layer, after the kidney was exposed.

Animal Grouping

A total of seven mice comprised the pseudosurgery group (group A), 10 mice comprised the single 5/6 nephrectomy group (group B), and 10 mice comprised the AT1-KO plus single 5/6 nephrectomy group (group C). All three groups were allowed ordinary forage and water ad libitum. Ten mice were included in the single 5/6 nephrectomy plus SXND treatment group (group D). The decoction granule was prepared by the Department of Pharmaceutics in Shuguang Hospital with the following herbs: rhubarb, 15 g; Salvia miltiorrhiza, 15 g; semen persicae, 15 g; radix astragali, 30 g; hartshorn, 20 g; radix curcumae, 15 g; and Rhizoma smilacis glabrae, 15 g. The drug was used for gavage once a day, with dosage converted to a proportion of 1:20 between mouse and human.

Ten mice composed the AT1-KO plus 5/6 nephrectomy plus SXND treatment group (Group E); the drug components, preparation, and dosage were the same as those mentioned previously. After 12 weeks of treatment, parameters were determined as above.

Detection Indices and Methods

Blood urea nitrogen (BUN) and SCr were determined by the Laboratory Center of Shuguang Hospital. Left ventricular end-diastolic diameter (LVDD), left ventricular end-systolic diameter (LVDS), fractional shortening (FS), and ejection fraction (EF) shown by echocardiography with high-resolution small animal ultrasound system (Vevo770 High-Resolution Imaging System) were determined with assistance from the Fudan University Biomedical Research Institute. Cardiac ultrastructure was examined under a transmission electron microscope (Tecnai-12 BioTmin) in the electron microscope room of the Shanghai University of Traditional Chinese Medicine. Blood brain natriuretic peptide (BNP) kits for the enzyme-linked immunosorbent assay were purchased from Wuhan Boster Company, and procedures were carried out according to the manufacturer's instructions. The agents for immunohistochemistry (IHC) for collagen types I and III in the kidney and heart were purchased from ABCAM Company. For IHC, five sections were taken for every cardiac or renal sample, and five batches of experiments were made at different times. Positive signals in the whole section were selected with Image-pro plus to undergo image analysis, and the positive staining area was calculated. Western blot analysis was performed according to the following procedures: homogenization of heart tissue, extraction of plasmocin, electrophoresis, transference, sealing with BSA or nonfat dried milk, incubation with primary antibody, incubation with secondary antibody, chemiluminescence, and image analysis.

Statistical Analysis

Statistical data were expressed in [INSIDE:1] Student's t-test was used to compare the mean between two groups. One-way ANOVA was employed to compare the mean between two or more groups. Non-parametric test was carried out for data with heterogeneity of variance.

Results

Vector Construction

An expression vector was successively constructed according to the vector construction strategy and validated with enzyme digestion [Figure 1]b and 1c.

Identification on Heterozygote Mice

F1 generation mice positive in both arms were obtained through identification by PCR on their DNA extracted from the tail genome of mice with gray hair. These mice were the offspring of the C57BL/6J female mice mated with the adult male mice with a chimeric rate of over 50% [Figure 1]d.

Survival of the Animals

During the whole experiment, one mouse from Group D and two mice from Group E died because of gavage. One mouse from Group B died because of a fight, and one mouse each from Groups B and C died for unknown reasons. All mice in Group A survived.

Blood BUN and SCr

Amelioration of BUN was observed in Groups D and E after SXND therapy. The blood BUN of both groups had statistical significance (P < 0.05) compared with the baseline parameters. Statistical significance was observed in Group E compared with either of the two modeling groups, namely, Groups B and C (P < 0.05). Amelioration of SCr was significant in Group E compared with either Groups B or C (P < 0.05) [Table 1].{Table 1}

Blood BNP

Group comparisons after treatment revealed, BNP was significantly elevated to various extents in the modeling groups compared with Group A. Specifically, statistical significance was observed in Groups B and D compared with Group A (P < 0.05-0.01) as well as in Group B compared with Groups E and B (P < 0.05) [Table 1].

LVDD and LVDS in Echocardiography

Statistical significance was observed for LVDD in either Groups B or C compared with the baseline parameters (P < 0.05-0.01). Statistical significance was also observed in Group B compared with Groups A, D, or E (all P < 0.05). A significant difference was observed for LVDS in Group B compared with Groups C, D, or E (all P < 0.05; [Table 2]).{Table 2}

FS and EF in Echocardiography

Statistical significance was observed for FS in Group B post-treatment compared with the baseline parameter (P < 0.05) and with Groups C, D, and E post-treatment (all P < 0.05). Significant difference was observed for EF in Group B compared with Groups C, D, or E (all P < 0.05; [Table 2]).

Variation in Collagen Types I and III in the Heart and Kidney

The essence of cardiac fibrosis is the re-modeling of the extracellular matrix (ECM) in the heart because of the imbalance between the synthesis and degradation of ECM. Cardiac fibrosis is characterized by increased collagen deposition in the matrix, disproportionality among various collagens with raised ratio of collagen types I and III, and disorderly arrangement. The results of this study show increased positive expression of collagen types I and III in the two modeling groups (Groups B and C) compared with the normal group (Group A) (P < 0.05-0.01) and a mild decrease in expression of the same collagens in the AT1-KO group post-remodeling. Amelioration in the positive expression of collagen types I and III post-treatment with SXND was observed in either Group D or E compared with each of the modeling groups (P < 0.05-0.01). Consistency was observed in the aforementioned manifestations in both the heart and the kidney [Table 3].{Table 3}

Transforming Growth Factor ί1 (TGF-ί1) Western Blot

Previous studies have proved that the increase of angiotensin (Ang II) and activated RAS are the main factors that cause myocardial fibrosis. [12] Meanwhile, TGF-β1, one of the cytokines, is the most important growth factor capable of promoting fibrosis. The activated TGF-β1 may inhibit ECM degradation, promote expression and ECM mRNA, and improve DNA synthesis. [13] Many studies have proved that myocardial fibrosis induced by RAS activation and promoted Ang II is caused by increased TGF-β1. TGF-β1 forms common pathways that lead to myocardial fibrosis induced by multiple factors. The result of this study revealed increased TGF-β1 in the heart in Groups B, C, D, and E after modeling of renal failure (P < 0.05-0.01). A significant drop in TGF-β1 content was observed in Group C than in Group B. TGF-β1 decreased to some extent after SXND treatment. These findings suggest the presence of a potential correlation between the influence of cardiac remodeling on TGF-β1 and amelioration [Table 4], [Figure 1], 1-5].{Table 4}{Figure 1}

Myocardial Ultrastructure

Observations with transmission electron microscopy were as follows. In Group A, the morphology of the myocardial cells remained normal with clear myofilaments. The plasma was rich in the circle or oval mitochondria with densely and orderly arranged crests that fill up the whole lumen. Swelling or vacuolar degeneration of mitochondria was absent, whereas merisis and growth, which are rarely observed in mitochondria, were observed. In Group B, certain disorderly arrangement, rupture, and dissection were observed in the myofibrils of the myocardial cells. Other observations included the following: blurred structure of sarcomere bands, loosely arranged and focally dissolved myofilaments, decreased quantity of mitochondria arranged irregularly with swelling, incomplete outer membrane, shrinkage and sparseness of crests, and presence of lipid droplets and vacuoles. In Group C, the following observations were also made: a significant decrease in the number of mitochondria arranged irregularly with swelling, incomplete outer membrane, shrinkage and sparseness of crests, and presence of lipid droplets and vacuoles. In Group D, a clear myocardial structure was observed with mild swelling of mitochondria with a few vacuoles. Sparsity in the arrangement of local myofilaments was also noticed but without rupture. In Group E, a clear myocardium structure was observed, along with greater amelioration of mitochondria swelling compared with the modeling group. An obvious increase in the number of mitochondria was also observed with droplet and vacuoles formation but without myofilament rupture [Figure 2].{Figure 2}

Discussion

Activation of RAS is one of the main causes of cardiac remodeling due to CRI. In recent years, considerable attention has been given to the interaction between the heart and the kidney, and a new five-type classification for cardio-renal syndrome (CRS) has been proposed. [14] The subjects of this research belonged to type 4 CRS, i.e. the VCDs caused by CKD in uremia condition. They have similar pathological profiles in the myocardium (e.g. hypertrophy, elongation, apoptosis, and death), mesenchyme (e.g. fibrosis), and remodeling of blood vessels (cardiac remodeling). We believe that the characteristics of the above-mentioned disease are related with the activation of RAS during CRI.

RAS is important in sustaining the normality in blood pressure, water-electrolyte balance, and stability in internal environment. Activated RAS may increase the working load of the heart, thereby inducing changes in cardiac structure, hypertrophy of myocardial cells, thickening of the strata medium of myocardium and its fibrosis, cardiac remodeling, and even heart failure. [2] Cardiac fibrosis, which may occur in various CVDs, is mainly characterized by an increased number of myocardial fibroblasts and excessive deposit of collagen in ECM of myocardium. Increasing evidence indicates that RAS-mediated myocardial fibrosis is one of the key pathological profiles of all kinds of cardiac remodeling.

AT1-KO mouse model can effectively delay cardiac remodeling due to CRI

Ang II, the formation of which is catalyzed by angiotensin-converting enzyme (ACE), is the main molecular of RAS. Ang II plays its roles in heart cells through endocrine, autocrine and paracrine hormone, and nitracrine pathways. [15],[16] There are four kinds of angiotensin II receptor subtypes, namely AT1, AT2, AT3, and AT4. AT1 and AT2 receptors play an important role in regulating blood pressure. So far, all ARB drugs are targeted at AT1 receptor to play their roles. The physiological role of AT2 receptors is not entirely clear. The reason is the low expression of AT2 receptors in healthy adults, only in the brain, ovaries, and kidneys. [17]

Mercure et al. showed that long-term injection of Ang II induced hypertension in wild-type mice and caused myocardial hypertrophy and fibrosis, expression of TGF-β1, and activation of AT1 receptor. [18] As proven by another research, [15] combining Ang II with AT1 receptor may mediate multiple cardiovascular responses, such as vascular contraction, mitosis, myocardial hypertrophy and fibrosis, inflammation, and apoptosis of myocardial cells. [15]

This study used AT1-KO mice whose AT1 receptor in the RAS signaling pathway was knocked out to block the RAS system. Modeling was then performed with 5/6 nephrectomy; the model was compared with a single nephrectomy model. The results are as follows. 1. Antagonization against RAS did not affect the renal function in CRI, as no statistical difference was observed in BUN or SCr between Groups C and B. 2. Antagonization against RAS could obviously affect the ventricular remodeling in CRI, given the statistical difference (P < 0.05) observed in LVDS, FS, EF, or BNP between Groups C and B, 12 weeks after modeling. 3. Myocardial ultrastructure could not be influenced by RAS antagonization, given the following observations: obvious decrease of myocardial mitochondria with irregular arrangement, swelling, incomplete outer membrane, decreased number of crest, and presence of lipid droplets or vacuoles in Group D, which showed no amelioration compared with Group B.

SXND can further improve cardiac remodeling in AT1-KO mice with CRI.

SXND from the Chinese Herbal Compound is an empirical formula that we have established based on our long-term clinical practice. It consists of the following herbs: rhubarb, 15 g; Salvia miltiorrhiza, 15 g; semen persicae, 15 g; radix astragali, 30 g; hartshorn, 20 g; radix curcumae, 15 g; and Rhizoma smilacis glabrae, 15 g. Previous studies have concluded the main mechanism of SXND in ameliorating ventricular remodeling in CRI into two aspects, namely, lowering of uremia toxins and amelioration of RAS functions.

In this research, a comparison between ventricular remodeling with CRI in AT1-KO mice treated with SXND and ventricular remodeling with simple CRI revealed that: (1) SXND could ameliorate to some extent renal function of mice with CRI, which was reflected by the statistical significance in BUN comparison between its levels prior to and post-treatment in Group D or E (P < 0.05), and lowered mean of SCr despite the lack of significance. (2) A synergistic effect was observed between SXND and antagonism against RAS to ameliorate the renal function of CRI mice, which was reflected by the statistical significance in BUN and SCr post to treatment in Group E compared with Groups B and C (all P < 0.05) in contrast to the absence of significance in Group D, and the amelioration of IHC results for collagens of kidney. (3) SXND was capable of efficiently relieving ventricular remodeling in CRI, which was reflected by the significance of LVDD, LVDS, FS, EF, and BNP post-treatment in Group B but not in Group E compared with Group C or D, suggesting the amelioration of ventricular remodeling in CRI by SXND did not rely upon completely RAS antagonism; improvement in myocardial IHC results were observed in each of the treatment groups;

(4) Abnormality in ultra microstructure of myocardium involved in ventricular remodeling in CRI could be ameliorated by SXND, which was reflected by the improvement on both structure and quantity of mitochondria in Groups D and E. This amelioration was characterized in its independence upon RAS, which was reflected by the effective amelioration of ultra microstructure in Groups E and D. (5) SXND relieved renal fibrosis and cardiac remodeling by ameliorating various cytokines involved in cardiac remodeling and/or found in kidney tissues, especially the expression of TGF-β1 followed by the amelioration of ECM deposits of fibronectin, laminin, and collagen type I and III, and there seemed to be a correlation between the heart and kidneys.

Conclusion

RAS plays an important role in the development of ventricular remodeling in CRI. Antagonism against RAS may effectively ameliorate ventricular remodeling; however, it will not bring any benefit for cardiac ultra microstructure or for the amelioration of renal function. SXND may efficiently improve CRI in chronic renal failure and combine with antagonism against RAS. SXND may efficiently relieve ventricular remodeling in CRI, and its functions can be characterized by their capability to not only ameliorate RAS and decrease uremic toxins but also correlate with the amelioration of myocardial ultra microstructure such as mitochondrial functions. [5] The therapeutic efficacy of SXND described above may be correlated with the amelioration of TGF-β1 excreted by the heart or kidney.

References

1	Saran AM, Dubose TD Jr. Cardiovascular disease in chronic kidney disease. Ther Adv Cardiovasc Dis 2008;2:425-34.
2	Grobe JL, Mecca AP, Lingis M, Shenoy V, Bolton TA, Machado JM, et al. Prevention of angiotensinII- induced cardiac remodeling by angiotensin-(1-7). Am J Physiol Heart Circ Physiol 2007;292:H736-42.
3	Wu Y, Yang L, Zhong L. Decreased serum levels of thioredoxin in patients with coronary artery disease plus hyperhomocystememia is strongly associated with the disease severity. Atherosclerosis 2010;212:351-5.
4	Andress DL, Coyne DW, Kalantar-Zadeh K, Molitch ME, Zangeneh F, Sprague SM. Management of secondary hyperparathyroidism in stages 3 and 4 chronic kidney disease. Endocr Pract 2008;14:18-27.
5	Walker AM, Schneider G, Yeaw J, Nordstrom B, Robbins S, Pettitt D. Anemia as a predictor of cardiovascular events in patients with elevated serum creatinine. J Am Soc Nephrol 2006;17:2293-8.
6	Wierzbicki AS. Hot and bothered: C-reactive protein, inflammation and atherosclerosis. Int J Clin Pract 2009;63:1550-3.
7	Shibasaki Y, Nishiue T, Masaki H, Matsubara H, Iwasaka T. Angiotensin II type 1 antagonist suppress left ventricular hypertrophy and myocardial fibrosis in patient with end stage renal disease (ESRD). Nihon Rinsho 2002;60:1992-8.
8	Yang XJ, He LQ. Effects of shenxinning decoction (SXND) and its decomposed formulas on cardiac remodeling in chronic renal failure rats. Shanghai J Tradit Chinese Medi 2007;41:63-7.
9	Yang XJ, Liu WF, He LQ. Clinical study on combined shenxinning decoction (SXND) and routine therapy for heart disease following chronic renal insufficiency. Shanghai J Traditional Chinese Med 2010;44:39-42.
10	Sugaya T, Nishimatsu S, Tanimoto K, Takimoto E, Yamagishi T, Imamura K, et al. Angiotensin II type 1a receptor-deficient mice with hypotension and hyperrreninemia. J Biol Chem 1995;270:18719-22.
11	Ronco C, House AA, Haapio M. Cardiorenal syndrome: Refining the definition of a complex symbiosis gone wrong. Intensive Care Med 2008;34:957-62.
12	Brilla CG. Renin-angiotensin-aldosterone system and myocardial fibrosis. Cardiovasc Res 2000;47:1-3.
13	Laviades C, Varo N, Diez J. Transforming growth factor beta in hypertensives with cardiorenal damage. Hypertension 2000;36:517-22.
14	Ronco C. Cardiorenal syndromes: Definition and classification. Contrib Nephrol 2010;164:33-8.
15	Stewart JA Jr, Lazartigues E, Lucchesi PA. The angiotensin converting enzyme 2/Ang-(1-7) axis in the heart: A role for mas communication? Circ Res 2008;103:1197-9.
16	Jin D, Takai S, Sugiyama T, Hayashi T, Fukumoto M, Oku H, et al. Long-term angiotensin II blockade may improve not only hyperglycemia but also age-associated cardiac fibrosis. J Pharmacol Sci 2009;109:275-84.
17	Reis RI, Santos EL, Pesquero JB, Oliveira L, Schanstra JP, Bascands JL, et al. Participation of transmembrane proline 82 in angiotensin II AT1 receptor signal transduction. Regul Pept 2007;140:32-6.
18	Mercure C, Yogi A, Callera GE, Aranha AB, Bader M, Ferreira AJ, et al. Angiotensin (1-7) blunts hypertensive cardiac remodeling by a direct effect on the heart. Circ Res 2008;103:1319-26.