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

Ethnopharmacological relevance

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

Materials and methods

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

Results

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

Conclusions

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

Protective effects of Zhibai Dihuang Wan on renal tubular cells affected with gentamicin-induced apoptosis

Ethnopharmacological relevance

Zhibai Dihuang Wan (ZDW) is an ancient traditional Chinese medicine composed of eight herbal ingredients and has been used to treat chronic kidney inflammation and diabetes for thousands of years. Nonetheless, the influence of ZDW on acute kidney injury is still unknown. We intended to identify the influence of ZDW on cell growth and gentamicin-induced apoptotic injury in renal tubular cells.

Materials and methods

We extracted ZDW with artificial intestinal fluid and treated rat renal tubular cells (NRK-52E) with various concentrations of the ZDW extraction. Cell proliferation and gentamicin-induced apoptosis of NRK-52E cells were evaluated using real-time proliferation monitoring and annexin V staining, respectively. Western blotting was used to evaluate the levels of Bcl-2 and caspase-3 expression. The effect of ZDW on gentamicin-induced kidney injury was also monitored in mice using the terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling (TUNEL) assay, and the measurement of serum creatinine and blood urea nitrogen.

Results

We found that 30 μg/ml of ZDW promoted cell proliferation of the rat renal tubular cells. ZDW also expressed a dose-dependent protective effect against gentamicin-induced apoptosis in the cells. Pretreatment with 3 μg/ml or 30 μg/ml of ZDW maximally increased Bcl-2 and decreased cleaved caspase-3 in the gentamicin-treated NRK-52E cells. Among the herbal ingredients of ZDW, only Phellodendron amurense Rupr., bark (Cortex Phellodendri), and Anemarrhena asphodeloides Bunge, rhizome inhibited both the gentamicin-induced Bcl-2 decrease and cleaved caspase-3 increase. Phellodendron amurense Rupr., bark and Anemarrhena asphodeloides Bunge, rhizome also inhibited gentamicin-induced apoptosis at particular concentrations; however, these two ingredients were less effective than ZDW. In the mouse model of gentamicin-induced nephropathy, the ZDW treatment significantly reduced apoptotic cells in the renal cortex and improved renal function.

Conclusions

Our results suggest that ZDW at adequate doses attenuates gentamicin-induced apoptotic injury in renal tubular cells and also protects kidneys from gentamicin-induced injury in mice.     

Clinical trials of traditional Chinese medicine in the treatment of diabetic nephropathy—A systematic review based on a subgroup analysis

Ethnopharmacological relevance

The purpose of this study is to systematically evaluate the efficacy of traditional Chinese medicine (TCM) decoctions with different ingredients in the treatment of diabetic nephropathy (DN).

Materials and methods

Papers obtained after the retrieval of randomized controlled clinical trials (RCTs) of TCM treatments of diabetic nephropathy through online database (e.g. Medline, CBM, CNKI, VIP, the online database of Chinese medicine, CDFD, CMFD, and CENTRAL FROM Cochrane Library, etc.) as well as research data in our library. They were published between January 2001 and December 2012. According to the categories of the main TCM ingredients, all the cases in the literature were divided into a liver–kidney YIN deficiency group, a QI-BLOOD YIN-and-YANG deficiency group, and a spleen–kidney YANG deficiency group. Stata 11.0 was applied for subgroup analysis.

Results

A total of 21 Chinese RCTs were included in this review. The Q values of the three groups were 13.18, 0.25 and 3.27, respectively, P>0.05, and thus, there was no clinical heterogeneity. The combined relative risk (RR) value and its 95% confidence interval were 1.48 (1.37, 1.60), 1.19 (1.06, 1.34), and 1.33 (1.19, 1.50), respectively, P<0.05.

Conclusions

Compared with the qi-blood yin-and-yang deficiency group and the spleen–kidney yang deficiency group, the liver–kidney yin deficiency group has better prospects in clinical application to ensure renal function during the treatment of DN, and this possibility is worthy of further study.     

Traditional Chinese herb Dihuang Yinzi (DY) plays neuroprotective and anti-dementia role in rats of ischemic brain injury

Aim of the study

Traditional Chinese herb Dihuang Yinzi (DY) is well known to treat neurological diseases by traditional Chinese medical practitioners. This study is to elucidate its neuroprotective and anti-dementia role in ischemic brain injury.

Materials and methods

The effects of DY on the pathohistological changes, lactate dehydrogenase (LDH) release, Morris water maze task, expression of synaptophysin (SYP) and extracellular signal-regulated protein kinase (ERK) of hippocampi of rats with ischemic brain injury were investigated.

Results

This study showed that DY not only significantly decreased the number of TUNEL-positive cells but also reduced the LDH release of hippocampus of model rat. Morris water maze test showed that the ability of learning and memory of rats dramatically impaired after ischemic brain injury. However, DY ameliorated the impairment of learning and memory of ischemic rats. Furthermore, western blotting and immunohistochemical data showed that the expression of extracellular regulated protein and synaptophysin, which correlates with synaptic formation and function, decreased after ischemic insult. However, DY inhibited the reduction of ERK an SYP expression in a dose-dependent way.

Conclusion

These results suggest that DY possesses neuroprotective and anti-dementia properties, at least in part, by preventing the loss of neural cells and synapses in ischemic brain injury.     

Pharmacokinetic comparisons of berberine and palmatine in normal and metabolic syndrome rats

Ethnopharmacological relevance

San-Huang formula is a popular traditional Chinese medicine (TCM) preparation to replenish Qi, resolve phlegm, dissipate blood stasis, and therapy metabolic syndrome in China. Metabolic syndrome, which is accompanied by Qi and blood stasis, mainly arises from spleen deficiency in essence. There is limited information available for differences of pharmacokinetic properties of San-Huang formula between normal and metabolic syndrome rats. The present study was conducted to compare the pharmacokinetics of berberine as well as palmatine in normal and metabolic syndrome rats following oral administration of San-Huang formula extract.

Materials and methods

The animals were orally administered with San-Huang formula extract with the equivalent dose of 60.4 and 12.5 mg/kg for berberine and palmatine, respectively. The blood samples were collected according to the time schedule. The concentrations of berberine and palmatine in rat plasma were determined by LC–ESI/MS. Various pharmacokinetic parameters were estimated from the plasma concentration versus time data using non-compartmental methods.

Results

It was found that AUC_0−t, C_max, Vd and CL of berberine and palmatine in metabolic syndrome rats were significantly different (P<0.05) from normal rats.

Conclusions

The results indicated that berberine and palmatine have higher uptake and slower elimination in the rats with metabolic syndrome, which suggests that the rate and extent of drug metabolism were altered in metabolic syndrome rats.     

Metabonomics study of the effects of pretreatment with glycyrrhetinic acid on mesaconitine-induced toxicity in rats

Ethnopharmacological relevance

Aconitum carmichaelii Debx. (Fuzi), a commonly use traditional Chinese medicine (TCM), has often been used in combination with Rhizoma Glycyrrhizae (Gancao) to reduce its toxicity due to diester diterpenoid alkaloids aconitine, mesaconitine, and hypaconitine. However, the mechanism of detoxication is still unclear. Glycyrrhetinic acid (GA) is the metabolite of glycyrrhizinic acid (GL), the major component of Gancao. In present study, the effect of GA on the changes of metabolic profiles induced by mesaconitine was investigated using NMR-based metabolomic approaches.

Materials and methods

Fifteen male Wistar rats were divided into a control group, a group administered mesaconitine alone, and a group administered mesaconitine with one pretreatment with GA. Their urine samples were used for NMR spectroscopic metabolic profiling. Statistical analyses such as orthogonal projections to latent structures-discriminant analysis (OPLS-DA), t-test, hierarchical cluster, and pathway analysis were used to detect the effects of pretreatment with GA on mesaconitine-induced toxicity.

Results

The OPLS-DA score plots showed the metabolic profiles of GA-pretreated rats apparently approach to those of normal rats compared to mesaconitine-induced rats. From the t-test and boxplot results, the concentrations of leucine/isoleucine, lactate, acetate, succinate, trimethylamine (TMA), dimethylglycine (DMG), 2-oxo-glutarate, creatinine/creatine, glycine, hippurate, tyrosine and benzoate were significantly changed in metabolic profiles of mesaconitine-induced rats. The disturbed metabolic pathways include amino acid biosynthesis and metabolism.

Conclusions

GA-pretreatment can mitigate the metabolic changes caused by mesaconitine-treatment on rats, indicating that prophylaxis with GA could reduce the toxicity of mesaconitine at the metabolic level.     

Rhodiola crenulata root ameliorates derangements of glucose and lipid metabolism in a rat model of the metabolic syndrome and type 2 diabetes

Ethnopharmacological relevance

Rhodiola species are traditionally used as tonics and stimulants to treat asthenia, suggesting their possible regulatory effect on energy metabolism. Clinical trials have demonstrated their glucose-lowering effect in type 2 diabetes.

Aim of the study

To examine the effects of Rhodiola on glucose and lipid metabolism in the metabolic syndrome and type 2 diabetes.

Materials and methods

Zucker diabetic fatty (ZDF) rats were treated with Rhodiola crenulata root (RCR) powder (100 and 500 mg/kg, by gavage, once daily for 4 weeks). In addition, the effects of RCR on sucrose-induced acute hyperglycemia in mice and olive oil-induced hypertriglyceridemia in rats were also examined. Biochemical variables were determined enzymatically or by ELISA.

Results

In ZDF rats, RCR treatment decreased the increased plasma insulin and triglyceride concentrations at baseline, the index of the homeostasis model assessment of insulin resistance (HOMA-IR) and excessive hepatic triglyceride accumulation. This treatment also inhibited abnormal increases in plasma glucose and insulin concentrations during oral glucose tolerance test. Furthermore, RCR reversed the increased adipose insulin resistance index, and accelerated the decline of plasma concentrations of non-esterified fatty acids after exogenous glucose stimulation. However, RCR minimally affected sucrose-induced acute hyperglycemia in mice and olive oil-induced acute hypertriglyceridemia in rats.

Conclusions

The present results demonstrate that RCR treatment improves metabolic derangements in animal model of the metabolic syndrome and type 2 diabetes. Our findings may provide new pharmacological basis of therapeutics for the adaptogenic plants to treat metabolic derangements-associated disorders, such as asthenia.     

Triptolide promotes generation of FoxP3+ T regulatory cells in rats

Ethnopharmacological relevance

Triptolide (TPT), a component of the Chinese herb Triptergium wilfordii, has potent immunosuppressive and anti-inflammatory activity and is used clinically in recipients of kidney transplantation.

Aim of the study

This work aimed to investigate the effect of TPT on the differentiation of regulatory T lymphocytes (Tregs) from CD4+ cells in rats.

Materials and methods

MACS-purified rat CD4+ cells were costimulated with anti-CD3 and anti-CD28 in the presence of TGF-β to induce the expression of FoxP3, which was detected by flow cytometry. TPT and cyclosporine A (CsA) were separately added into the cultures to observe the effect on the expression of FoxP3. Kidney transplantation was performed in rats that either received no treatment or were treated with TPT after transplantation.

Results

TPT treatment enhanced the expression of FoxP3 in CD4+ cells, whereas CsA inhibited the FoxP3 expression. In the rat kidney transplantation model, the recipient rats treated with TPT survived longer than the control rats (18–19.83 vs 6.83 days, P < 0.05). Meanwhile, the FoxP3+ T cells in the spleens of treated rats were higher than those from the untreated rats (12.4% vs 4.7%, P < 0.05).

Conclusions

These data suggest that TPT may promote the differentiation of CD4+ cells to FoxP3+ Tregs. This would be at least one of the pathways responsible for the immunosuppressive activity of TPT.     

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.     

Toxicity studies of Tithonia diversifolia A. Gray (Asteraceae) in rats

Objective

To investigate the toxicity of an ethanolic extract of the aerial parts of Tithonia diversifolia, used in Nigeria to treat malaria, in rats.

Materials and methods

A 70% ethanol extract was administered orally to adult Wistar rats at various dosages (400–1600 mg/kg) and the animals sacrificed and various organs examined at a range of times from 30 min up to 24 h after administration.

Results

The studies showed a dose- and time-dependent toxic effect, which was reversible on the kidney and liver while there was no noticeable adverse effect on the morphology of the heart, spleen and brain.

Conclusion

A 70% ethanol extract of the aerial parts of Tithonia diversifolia, which had previously been shown to reduce parasitemia in mice infected with Plasmodium, displayed kidney and liver toxicity at the lowest dose tested. The use of this plant extract against malaria therefore raises concerns over its safety.     

Hachimijiogan (Ba-Wei-Di-Huang-Wan), a herbal medicine,improves unbalance of calcium metabolism in aged rats

Aim of the study

Aged animals as well as elderly humans commonly exhibit calcium (Ca) shortage because of increased Ca excretion into urine and decreased intestinal Ca absorption, which induce elevation of serum PTH levels to maintain serum Ca levels between a normal physiological range. The most important organ that regulates this Ca homeostasis is the kidney. Hachimijiogan (HJG), a traditional herbal medicine in Japan and China, has been used for treating clinical diseases associated with kidney dysfunctions in elderly humans. However, the mechanisms of its pharmacological actions remain to be understood poorly. The present study was designed to examine whether HJG improves age-related unbalance of Ca metabolism at the systemic level using aged rats.

Materials and methods

HJG was administered to 21-month-old aged rats for 3 months, and several parameters associated with Ca metabolism in serum and urine were measured.

Results

Although HJG as well as aging itself did not affect serum Ca levels compared to young (11-week-old) rats, HJG improved increase in urinary Ca excretion and elevation of serum parathyroid hormone (PTH) levels in aged rats. However, HJG did not improve marked reduction of intestinal Ca absorption in aged rats.

Conclusion

HJG showed regulating action for age-related unbalance of Ca metabolism at the systemic level. This finding would provide useful information for treating age-related several disorders associated with Ca unbalance.     

Pharmacokinetics and tissue distribution of resveratrol,emodin and their metabolites after intake of Polygonum cuspidatum in rats

Ethnopharmacological relevance

The rhizome of Polygonum cuspidatum SIEB. et ZUCC. (Polygonaceae, PC), a widely used Chinese medicine, is commonly prescribed for the treatments of amenorrhea, arthralgia, jaundice, abscess, scald and bruises.

Aim of the study

PC contains various polyphenols including stilbenes, anthraquinones and flavonoids. This study investigated the pharmacokinetics and tissue distribution of emodin and resveratrol in PC.

Material and methods

Male Sprague-Dawley rats were orally administered PC (2 and 4 g/kg) and blood samples were withdrawn at the designed time points via cardiopuncture. Moreover, after 7-dose administrations of PC (4 g/kg), brain, liver, lung, kidney and heart were collected. The concentrations of resveratrol and emodin in the plasma and tissues were assayed by HPLC before and after hydrolysis with β-glucuronidase and sulfatase.

Results

The glucuronides/sulfates of emodin and resveratrol were exclusively present in the plasma. In liver, kidney, lung and heart, the glucuronides/sulfates of resveratrol were the major forms. For emodin, its glucuronides/sulfates were the major forms in kidney and lung, whereas considerable concentration of emodin free form was found in liver. Neither free forms nor conjugated metabolites of resveratrol and emodin were detected in brain.

Conclusion

The sulfates/glucuronides of resveratrol and emodin were the major forms in circulation and most assayed organs after oral intake of PC. However, the free form of emodin was predominant in liver.     

Beneficial metabolic effects of the Malaysian herb Labisia pumila var. alata in a rat model of polycystic ovary syndrome

Aim of the study

New options are needed to prevent and treat metabolic disorders associated with polycystic ovary syndrome (PCOS). Labisia pumila var. alata (LPva)—a Malaysian herb thought to have phytoestrogenic effects—has shown promise in reducing body weight gain in ovariectomized rats. In this study, we investigated the effect of LPva on body composition and metabolic features in female rats treated continuously with dihydrotestosterone, starting before puberty, to induce PCOS.

Material and methods

At 9 weeks of age, the PCOS rats were randomly subdivided into two groups; PCOS LPva and PCOS control. PCOS LPva rats received a daily oral dose of LPva (50 mg/kg body weight), dissolved in 1 ml of deionised water, for 4–5 weeks. PCOS controls received 1 ml of deionised water on the same schedule.

Results

LPva increased uterine weight (27%) and insulin sensitivity (36%) measured by euglycemic hyperinsulinemic clamp. Plasma resistin levels were increased and lipid profile was improved in LPva rats. In adipose tissue, LPva decreased leptin mRNA expression but did not affect expression of resistin and adiponectin. No effects on body composition, adipocyte size, or plasma leptin levels were observed.

Conclusion

LPva increases uterine weight, indicating estrogenic effects, and improves insulin sensitivity and lipid profile in PCOS rats without affecting body composition.     

知柏地黄丸对抑那通诱导特发性性早熟小鼠模型的干预作用

目的观察知柏地黄丸对抑那通诱导的特发性中枢性性早熟（ICPP）模型小鼠的影响。方法选用18日龄BALB／c雌性小鼠,随机分为5组：正常对照组,ICPP模型组,知柏地黄丸高、低剂量组（剂量分别为101．4g·kg^-1·d^-1、50．7g·kg^-1·d^-1）。甲地孕酮对照组（剂量为3．9mg·kg^-1·d^-1）;除正常对照组外,其他各组均给予促性腺激素释放激素拟似物抑那通,首次剂量为1573．5雌／kg,第2次、第3次剂量均为1180μg／kg,隔日1次,复制模型;检测各组小鼠阴道开口数,体重,血清雌二醇（E2）和黄体生成素（LH）水平,子宫、卵巢重量,计算子宫指数和卵巢指数,子宫和阴道脱落细胞涂片,卵巢组织病理学变化等。结果知柏地黄丸高剂量组于造模第3_4天对抑那通所致阴道开口提前有抑制作用（P〈0．05,P〈0．01）,知柏地黄丸低剂量组于造模第2-5天对抑那通所致阴道开口提前有抑制作用（均P〈0．05,P〈0．01）,甲地孕酮对照组于造模第3天对抑那通所致阴道开口提前有抑制作用（P〈0．05）;知柏地黄丸高剂量组可降低抑那通所致子宫重量增加（P〈0．05）,知柏地黄丸低剂量组及甲地孕酮对照组均可降低抑那通所致子宫、卵巢重量增加及子宫指数和卵巢指数的升高（P〈0．01）;高、低剂量的知柏地黄丸及甲地孕酮均有抑制抑那通降低E2水平的作用（P〈0．05,P〈0．01）,各给药组对抑那通升高LH水平、诱导阴道角化细胞的出现及排卵后出现的子宫内膜分泌期改变无明显影响。结论知柏地黄丸对抑那通刺激诱导的ICPP模型具有一定的对抗作用,其机制可能是通过抑制HPGA的靶腺（性腺）而起作用。