Euonymus alatus in the treatment of diabetic nephropathy in rats

The water extracts of Euonymus alatus (Thunb.) Siebold attenuate diabetic retinopathy by mediating angiogenesis

ETHNOPHARMACOLOGICAL RELEVANCE

Euonymus alatus (Thunb.) Siebold (family Celastraceae) is a deciduous woody shrub that is recorded in ShenNong BenCaoJing. It has been widely used for diabetes in traditional Chinese medicine.

AIM OF THE STUDY

This study aimed to identify the most effective extract of Euonymus alatus (EA) against high glucose-induced endothelial cells in vitro, evaluate its pharmacological effect on retinopathy in diabetic mice and explore its underlying mechanism by RNA sequencing.

METHODS

Retinal vascular endothelial cells (RF/6A) were treated with normal glucose (5.5 mmol/L glucose), high glucose (25 mmol/L glucose) or high glucose plus methanol extracts of EA (MEA), ethyl acetate extracts of EA (EEA) or water extracts of EA (WEA). The cytotoxicity and cell viability were determined by Cell Counting Kit-8 (CCK-8) assay. Cell migration was examined using the Transwell assay, and tube formation ability was measured using the Matrigel assay. Then, the KK-Ay mice were administered WEA or water for 12 weeks. The velocities of ocular blood flow were determined by Doppler ultrasound. RNA sequencing and reverse transcription quantitative PCR (RT-qPCR) were performed on WEA-stimulated RF/6A cells to reveal the underlying mechanism.

RESULTS

The cytotoxicity assay found that 30 μg/mL MEA, 20 μg/mL EEA and 30 μg/mL WEA had no toxic effect on RF/6A cells. The cell viability results showed that MEA, EEA and WEA all decreased cell viability. Compared with the high-glucose group, both MEA and WEA decreased the number of migrated cells, while the inhibition rate of WEA was higher. The Matrigel results showed that 30 μg/mL WEA effectively reduced the total tube length. Moreover, WEA improved the haemodynamics of the central retinal artery. RNA sequencing coupled with RT-qPCR verified that WEA regulated angiogenesis-related factors in high glucose-stimulated RF/6A cells.

CONCLUSIONS

WEA inhibits the migration and tube formation of RF/6A cells and improves diabetic retinopathy (DR) by mediating angiogenesis.

HuoXue JieDu formula improves diabetic retinopathy in rats by regulating microRNAs

ETHNOPHARMACOLOGICAL RELEVANCE

HuoXue JieDu Formula (HXJDF) originates from classical formulas and was formed based on clinical experience. It is composed of Euonymus alatus (Thunb.) Siebold, Panax notoginseng (Burkill) F.H. Chen, the roots of Anguina kirilowii (Maxim.) Kuntze, and Coptis omeiensis (C. Chen) C.Y.Cheng. HXJDF prevents the deterioration of diabetic retinopathy.

AIM OF THE STUDY

To evaluate the effects of HXJDF on diabetic retinopathy in rats and investigate the roles of miRNAs in the effects of HXJDF.

MATERIALS AND METHODS

A single intraperitoneal injection of streptozotocin (STZ) (65 mg/kg) was used to induce diabetes in rats. Rats were divided into three groups: normal, diabetic, and diabetic + HXJDF. Rats were treated with HXJDF (15.4 g/kg) or water by oral gavage for twelve weeks. At the end of the treatment, rats were anaesthetized, and retinal haemodynamic changes were measured. Then, the retinas were removed and examined by haematoxylin and eosin (HE) staining and TUNEL assays. In addition, miRNA expression profiling was performed using miRNA microarrays and further validated by quantitative real-time PCR (qRT-PCR).

RESULTS

Diabetes reduced peak systolic velocity (PSV), end-diastolic velocity (EDV), mean velocity (MV) and central retinal vein velocity (CRV) but increased the resistance index (RI) and pulsatility index (PI). In addition, in the diabetic group, retinal cell arrangement was disordered and loosely arranged, the retinal thickness and retinal ganglion cell (RGC) number decreased, and retinal cell apoptosis increased. In addition, 11 miRNAs were upregulated and 4 miRNAs were downregulated. After treatment, HXJDF improved retinal haemodynamics and morphologic changes, restored retinal thickness and RGC number and decreased retinal cell apoptosis. Furthermore, the changes in miRNA expression were significantly abolished by HXJDF.

CONCLUSION

HXJDF may prevent DR by regulating the expression of miRNAs.

Traditional uses, botany, phytochemistry, pharmacology, separation and analysis technologies of Euonymus alatus (Thunb.) Siebold: A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

Euonymus alatus (Thunb.) Siebold (E. alatus), a well-known medicinal plant, has been widely used thousands of years in China for the treatment of various diseases such as urticaria, dysmenorrhea, wound, dysentery, blood stasis, rheumatism and arthritis. Due to the extensive application of E. alatus in the fields of ethnopharmacological usage, the pharmaceutical researches of E. alatus keeps deepening.

AIM OF THE STUDY

This paper reviewed and summarized the integrated research progress of this medicinal plant. A comprehensive summary and comparison of traditional usages, botany, phytochemistry, pharmacology, toxicology, separation and analysis technologies of the E. alatus highlight recent scientific advances, which provides new insights into the research and development of this medicinal plant and would be helpful to promote the research situation of underlying pharmacological mechanisms and further utilizations of E. alatus.

MATERIAL AND METHODS

Literature survey was carried out via classic books of herbal medicine, PhD. and MSc. Dissertations. Online scientific databases including Pubmed, SciFinder, Science Direct, Scopus, the Web of Science, Google Scholar, China National Knowledge Infrastructure (CNKI) and others were searched up to February 2020 to identify eligible studies. All literatures of the research subject are analyzed and summarized in this review.

RESULTS

The E. alatus has been widely used in traditional practice in China, Korea and other Asian Countries. In the study of phytochemistry, more than 230 chemical constituents have been isolated and identified from E. alatus, including sesquiterpenoids, diterpenoids, triterpenoids, flavonoids, phenylpropanoids, lignans, steroids, alkaloids and other compounds. Among them, literature reports show that flavonoids and steroids are the most important bioactive substances found in this plant. A number of researches also have shown that extracts and compounds from E. alatus exert a wide spectrum of pharmacological effects, including antidiabetic effect, anti-tumor effects, anti-inflammatory effects, hepatoprotective effects, antioxidant effects, antibacterial effects, as well as other effects. However, most of the studies without clinical research. Research into plant's toxicological effects has also been limited. In addition, this review also summarizes and compares the separation and analysis technologies of E. alatus.

CONCLUSIONS

E. alatus has potential for the treatment of many diseases, especially tumors and diabetes. But many traditional uses of E. alatus have not been validated by current investigations. Additionally, modern studies haven't gone far enough into its pharmacological effects and the corresponding chemical constituents, more efforts should be made to illuminate the underlying mechanisms of E. alatus for treatment of tumors and diabetes. Moreover, the toxicological effects of this plant can be further studied. Currently, there are limited studies on its side effects and toxicological effects, which should provide further guidance for the safety of clinical use.

Compounds isolated from Euonymus spraguei Hayata induce ossification through multiple pathways

The process of bone metabolism includes catabolism of old or mature bone and anabolism of new bone, carried out by osteoclasts and osteoblasts respectively. Any imbalance in this process results in loss of bone mass or osteoporosis. Drugs available to combat osteoporosis have certain adverse effects and are unable to improve bone formation, hence identifying new agents to fulfil these therapeutic gaps is required. To expand the scope of potential agents that enhance bone formation, we identified Euonymus spraguei Hayata as a plant material that possesses robust osteogenic potential using human osteoblast cells. We isolated three compounds, syringaresinol (1), syringin (2), and (−)-epicatechin (3), from E. spraguei. Results demonstrated that syringin (2), and (−)-epicatechin (3), increased alkaline phosphatase activity significantly up to 131.01% and 130.67%, respectively; they also elevated mineral deposition with respective values of up to 139.39% and 138.33%. In addition, 2 and 3 modulated autophagy and the bone morphogenetic protein (BMP)-2 signaling pathway. Our findings demonstrated that 2 and 3 induced osteogenesis by targeting multiple pathways and therefore can be considered as potent multi-targeted drugs for bone formation against osteoporosis.

Dulcitol suppresses proliferation and migration of hepatocellular carcinoma via regulating SIRT1/p53 pathway

BACKGROUND

Hepatocellular carcinoma (HCC) spreads further with continuance and increasing incidence due to its high-grade malignancy and metastasis. More effectual strategies on blocking proliferation and metastasis of cancer cells should be studied in HCC. Dulcitol, a natural product extracted from euonymus alatus, was reported that it could induce apoptosis of C6 glioma cells. However, the underlying mechanism of Dulcitol on HCC remains unclea.

PURPOSE

In this study, we aimed to reveal the effect and potential mechanisms of Dulcitol on hepatocellular carcinoma in vitro and in vivo. Study design and methods The cell proliferation and apoptosis were evaluated by MTT, Ki-67 and Hoechst 33258/PI double staining. The migratory and invasive abilities of HepG2 cells were measured by wound-healing and transwell assays. Pathological changes of tumor tissue were observed by HE staining and IHC methods. The expression levels of protein were detected using Western Blot analysis.

RESULTS

The results showed that Dulcitol inhibited HepG2 cells proliferation by down-regulating the protein expression of SIRT1, Bcl-2, along with up-regulating p53, acetylated-p53 (K382), cleaved-caspase9, cleaved-caspase3, Bax, and cytochrome c in a dose-dependent manner. Furthermore, Dulcitol surpressed the migration and invasion of HepG2 cells through decreasing the levels of MMP-2, uPA and MMP-9 and increasing E-cadherin associated with tumor invasion. In vivo, Dulcitol distinctly inhibited the growth of HepG2 cancer xenograft tumors via inhibiting SIRT1/p53 pathway.

CONCLUSIONS

Our findings suggested that Dulcitol acted as a SIRT1 inhibitor, inducing apoptosis and inhibiting proliferation, migration and invasion of HepG2 cells and its modulatory mechanism seemed to be associated with regulation of MMPs, SIRT1/p53 pathways.

The protective effect of the active components of ERPC on diabetic peripheral neuropathy in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Euonymus alatus, Radix trichosanthis, Panax notoginseng and Coptis chinensis are popular plants used in traditional Chinese medicine to treat diabetes.

AIM OF THE STUDY

The aim of the study is to investigate the therapeutic effect of the active components of Euonymus alatus, Radix trichosanthis, Panax notoginseng and Coptis chinensis (cERPC) on diabetic peripheral neuropathy in the rats and explore the underlying mechanism involved.

METHODS

After diabetes was induced in rats for 20 weeks, cERPC or water was administered for 12 weeks. After a hot plate test, motor nerve conduction velocity and sciatic nerve blood flow were determined; the sciatic nerves were isolated for toluidine blue staining; and the fibre area, fibre diameter, axon area, axon diameter and myelin thickness were evaluated. The levels of the myelin basic protein, myelin protein zero, Oct6 and Krox20 were measured by western blot or immunofluorescence.

RESULTS

cERPC was efficient in reducing the response latency, increasing motor nerve conduction velocity, enhancing sciatic nerve blood flow and ameliorating the pathological changes in diabetic rats. cERPC also had a role in increasing the levels of myelin basic protein and myelin protein zero and improving the expression of Oct6 and Krox20 in sciatic nerves of diabetic rats.

CONCLUSIONS

cERPC ameliorates diabetic peripheral neuropathy by attenuating electrophysiological, circulatory and morphological alterations, which is mediated by the Oct6-Krox20 pathway.

Euonymus alatus: A Review on Its Phytochemistry and Antidiabetic Activity

Euonymus alatus (E. alatus) is a medicinal plant used in some Asian countries for treating various conditions including cancer, hyperglycemia, and diabetic complications. This review outlines the phytochemistry and bioactivities of E. alatus related to antidiabetic actions. More than 100 chemical constituents have been isolated and identified from E. alatus, including flavonoids, terpenoids, steroids, lignans, cardenolides, phenolic acids, and alkaloids. Studies in vitro and in vivo have demonstrated the hypoglycemic activity of E. alatus extracts and its certain constituents. The hypoglycemic activity of E. alatus may be related to regulation of insulin signaling and insulin sensitivity, involving PPARγ and aldose reductase pathways. Further studies on E. alatus and its bioactive compounds may help to develop new agents for treating diabetes and diabetic complications.

Effects of Tangshen Formula on urinary and plasma liver-type fatty acid binding protein levels in patients with type 2 diabetic kidney disease: post-hoc findings from a multi-center, randomized, double-blind, placebo-controlled trial investigating the efficacy and safety of Tangshen Formula in patients with type 2 diabetic kidney disease

Background

Tangshen Formula (TSF) is a traditional Chinese medicine for the treatment of diabetic kidney disease (DKD). Liver-type fatty acid binding protein (L-FABP) is expressed in various tissues, including the kidney, where it is known as urinary L-FABP. Other studies demonstrated that urinary L-FABP may be a useful biomarker for monitoring DKD. This post-hoc analysis and cross-sectional study evaluated the changes in urinary L-FABP in DKD patients treated with TSF and conventional medicine.

Methods

Post-hoc analysis was conducted on a multicenter, randomized, double-blind, placebo-controlled trial. A total of 180 participants with DKD including 98 with microalbuminuria and 82 with macroalbuminuria were enrolled in the original study. In addition to conventional treatment, 122 participants were randomly assigned to receive TSF and 58 to receive placebo. After 24-weeks of treatment, the intention-to-treat population in microalbuminuria stage was 56 in the TSF group and 25 in the placebo group, and in the macroalbuminuria stage 42 and 19, respectively. The primary outcome in the original trial was urinary protein level. In the current study, urinary and plasma L-FABP levels were measured in 30 microalbuminuria patients (15 in the TSF group and 15 in the placebo group) and 30 macroalbuminuria patients (15 in the TSF group and 15 in the placebo group). In addition, another 30 patients with normoalbuminuria (urinary albumin excretion rate (UAER) < 20 μg/min) were recruited for the cross-sectional study.

Results

(1) In microalbuminuria patients, UAER in the TSF group displayed a significant decrease after 24 weeks of treatment (P = 0.045). Levels of urinary L-FABP in the TSF group were markedly lower than in the placebo group after 12 and 24 weeks (P = 0.004 and P = 0.047, respectively). (2) In macroalbuminuria patients, 24-h urinary protein levels decreased significantly compared with baseline in the TSF group at week 12 (P = 0.042) and week 24 (P = 0.041). The TSF group showed a significant decrease in urinary L-FABP after 12 and 24 weeks (P = 0.036 and P = 0.046, respectively). (3) Levels of urinary L-FABP increased markedly, correlating with severity of DKD. L-FABP in patients with normoalbuminuria, microalbuminuria, and macroalbuminuria were 5.9 (5.2, 7.8) μg/ml, 11.4 (6.8, 13.4) μg/ml and 18.5 (10.9, 23.4) μg/ml, respectively (P = 0.000).

Conclusions

TSF combined with conventional therapy appeared to be effective in reducing urinary protein and urinary L-FABP. Urinary L-FABP levels appear to be associated with the severity of DKD.

Trial registration

Chinese Clinical Trial Registry ChiCTR-TRC-10000843. Registered 15 April 2010.

Chinese medicines in the treatment of experimental diabetic nephropathy

Diabetic nephropathy (DN) is a severe micro vascular complication accompanying diabetes mellitus that affects millions of people worldwide. End-stage renal disease occurs in nearly half of all DN patients, resulting in large medical costs and lost productivity. The course of DN progression is complicated, and effective and safe therapeutic strategies are desired. While the complex nature of DN renders medicines with a single therapeutic target less efficacious, Chinese medicine, with its holistic view targeting the whole system of the patient, has exhibited efficacy for DN management. This review aims to describe the experimental evidence for Chinese medicines in DN management, with an emphasis on the underlying mechanisms, and to discuss the combined use of herbs and drugs in DN treatment.

Efficacy and safety of tangshen formula on patients with type 2 diabetic kidney disease: a multicenter double-blinded randomized placebo-controlled trial

Background

Persons with diabetes are at high risk of developing diabetic kidney disease (DKD), which is associated with high morbidity and mortality. Current drug therapies for DKD, such as angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), are not entirely satisfactory. This study aimed to evaluate the additional benefit and safety of the Chinese herbal granule Tangshen Formula (TSF) in treating DKD.

Methods

The study was designed as a six-center randomized, double-blind, placebo-controlled trial. From April 2007 through December 2009, 180 patients with DKD were enrolled. In addition to conventional treatment with ACEIs or ARBs, 122 participants were randomly assigned to receive TSF and 58 participants to receive placebo for 24 weeks. Primary outcome was urinary protein level, measured by urinary albumin excretion rate (UAER) for participants with microalbuminuria, 24-hour urinary protein (24h UP) for participants with macroalbuminuria. Secondary outcomes included renal function, serum lipids, quality of life, symptoms, and adverse events.

Findings

After 24 weeks of treatment, no statistically significant difference in UAER (TSF −19.53 μg/min compared with placebo −7.01 μg/min, with a mean difference of −12.52 μg/min; 95%CI, −68.67 to 43.63, P = 0.696) was found between TSF and placebo groups. However, TSF displayed a statistically significant decrease in 24h UP (TSF−0.21 g compared with placebo 0.36 g, with a mean difference of −0.57g; 95%CI, −1.05 to −0.09, P = 0.024). Estimated glomerular filtration rate (eGFR) was improved in both patients with microalbuminuria and macroalbuminuria, with a mean difference of 15.51 ml/min/1.73 m² (95%CI, 3.71 to 27.31), 9.01 ml/min/1.73 m² (95%CI, −0.10 to 18.13), respectively. Other secondary outcomes showed no statistically significant difference between groups or in the incidence of adverse events.

Conclusions

Based on conventional treatments, TSF appears to provide additional benefits compared with placebo in decreasing proteinuria and improving eGFR in DKD patients with macroalbuminuria. Nevertheless, further study is needed to evaluate TSF treating patients with microalbuminuria.

Trial Registration

Chinese Clinical Trial Registry ChiCTR-TRC-10000843

Qiwei granules alleviates podocyte lesion in kidney of diabetic KK-Ay mice

BACKGROUND

Chinese medicine comprised of all natural herbs is widespread used in the treatment of diabetic nephropathy (DN). Podocyte contributes to the integrity of glomerular filtration barrier whose injury plays an important role in the initiation and progression of DN. Our study aimed to investigate the effect of Qiwei granules on podocyte lesion in diabetic KK-A(y) mice kidney and its underlying mechanism.

METHODS

Twelve-week-old male KK-A(y) mice were randomly divided in vehicle group and Qiwei granules group, while C57BL/6J mice were used as normal control. The mice were gavage with 1.37 g/kg/day Qiwei granules or water for 10 weeks. We measured water, food intake and body weight (BW) and fasting blood glucose (FBG) every 2 weeks, and urine protein every 4 weeks. At the end of the experiment, all surviving mice were sacrificed. The kidney weight and serum renal parameters were measured, and the renal morphology was observed. To search the underlying mechanism, we examined the podocyte positive marker, slit diaphragm protein expression and some involved cell signal pathway.

RESULTS

Qiwei granules treatment significantly improved the metabolic parameters, alleviated the urinary protein, and protected renal function in KK-A(y) mice. In addition, the glomerular injuries and podocyte lesions were mitigated with Qiwei granules treatment. Furthermore, Qiwei granules increased expression of nephrin, CD2AP, and integrin alpha3beta1 in the podocytes of KK-A(y) mice. Qiwei granules improved the phosphoration of Akt and inhibited cleaved caspase-3 protein expression.

CONCLUSION

These finding suggest that Qiwei granules protects the podocyte from the development of DN via improving slit diaphragm (SD) molecules expression and likely activating Akt signaling pathway in KK-A(y) mice.

Clinical efficacy of aconitum-containing traditional Chinese medicine for diabetic peripheral neuropathic pain

Diabetic peripheral neuropathy is a common chronic complication of diabetes. Routine clinical management uses analgesics to relieve pain in combination with drugs for nerve repair. The drugs are often not effective for the severe pain cases, and these western medications also have side effects. We report a more effective treatment of diabetic peripheral neuropathic pain using a high dose of a traditional Chinese medicine, aconitum (including both Radix aconite preparata and Radix aconite kusnezoffii), in combination with Huangqi Guizhi Wuwu Tang (i.e., astragalus, cassia twig, white peony root, and spatholobi). In order to achieve stronger analgesic effects, we increased the clinical dosage of aconitum from 15 to 120 g. The aconitum was boiled for 6-8 hours, and licorice was also used to reduce potential toxicities of aconitum. In the four reported cases, the patients' neuropathic pain was remarkably reduced and the EMG profile was also improved with this treatment regimen. Adverse reactions were not observed during the therapy. Thus, aconitum represents a promising and safe treatment for the well-being of patients and their diabetic peripheral neuropathic pain. Future controlled clinical trials using traditional Chinese medicines containing aconitum in treating the neuropathic pain are warranted.