Diabetes is an inflammatory disease: evidence from traditional Chinese medicines

Ginseng for the treatment of diabetes and diabetes-related cardiovascular complications: a discussion of the evidence 1

Diabetes mellitus (DM) is a chronic metabolic disorder associated with elevated blood glucose levels due either to insufficient insulin production (type 1 DM) or to insulin resistance (type 2 DM). The incidence of DM around the world continues to rise dramatically with more than 400 million cases reported today. Among the most serious consequences of chronic DM are cardiovascular complications that can have deleterious effects. Although numerous treatment options are available, including both pharmacological and nonpharmacological, there is substantial emerging interest in the use of traditional medicines for the treatment of this condition and its complications. Among these is ginseng, a medicinal herb that belongs to the genus Panax and has been used for thousands of years as a medicinal agent especially in Asian cultures. There is emerging evidence from both animal and clinical studies that ginseng, ginseng constituents including ginsenosides, and ginseng-containing formulations can produce beneficial effects in terms of normalization of blood glucose levels and attenuation of cardiovascular complications through a multiplicity of mechanisms. Although more research is required, ginseng may offer a useful therapy for the treatment of diabetes as well as its complications.

Syringaresinol‑di‑O‑β‑D‑glucoside, a phenolic compound from Polygonatum sibiricum, exhibits an antidiabetic and antioxidative effect on a streptozotocin‑induced mouse model of diabetes

Syringaresinol-di-O-β-D-glucoside (SOG) is a phenolic compound extracted from Polygonatum sibiricum. The present study aimed to investigate the antidiabetic effect of SOG on streptozocin (STZ)-induced diabetic mice and determine the potential underlying mechanisms. In the present study, fasting blood glucose and organ indexes of mice were analyzed. Body weight, water intake and food intake were also recorded. Furthermore, serum fasting insulin, pancreatic insulin and pancreatic interleukin-6 levels of mice were determined using ELISA kits to investigate the effect of SOG on the levels of insulin. Levels of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol, low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C) and free fatty acid (FFA) in the serum of mice, and levels of TC, TG and total protein in the kidney, were also determined to investigate the effects of SOG on lipid and protein metabolism in mice. Furthermore, malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), aspartate transaminase (AST), alanine transaminase (ALT) and alkaline phosphatase (ALP) levels, as well as total antioxidant capacity (T-AOC), in the kidneys of mice were determined to investigate the effect of SOG on oxidative stress. Western blotting was also performed to determine the expression of proteins associated with oxidative stress. The results demonstrated that SOG (25, 50 and 75 mg/kg) induced a significant antidiabetic effect in mice. Treatment with SOG promoted insulin secretion and decreased TC, TG, LDL-C, VLDL-C, FFA, MDA, SOD, CAT, AST, ALT and ALP levels in the kidneys of mice, as well as kidney TC and TG levels, but increased the levels of kidney total protein and the T-AOC in kidneys. Furthermore, SOG treatment could significantly downregulate the expressions of nitrotyrosine and transforming growth factor-β1 in diabetic mice. Therefore, the present study indicated that SOG may exert an antidiabetic effect on STZ-induced diabetic mice and that the mechanism of SOG may be associated with its antioxidative activity.

A Network Pharmacology Approach to Uncover the Molecular Mechanisms of Herbal Formula Ban-Xia-Xie-Xin-Tang

Ban-Xia-Xie-Xin-Tang (BXXXT) is a classical formula from Shang-Han-Lun which is one of the earliest books of TCM clinical practice. In this work, we investigated the therapeutic mechanisms of BXXXT for the treatment of multiple diseases using a network pharmacology approach. Here three BXXXT representative diseases (colitis, diabetes mellitus, and gastric cancer) were discussed, and we focus on in silico methods that integrate drug-likeness screening, target prioritizing, and multilayer network extending. A total of 140 core targets and 72 representative compounds were finally identified to elucidate the pharmacology of BXXXT formula. After constructing multilayer networks, a good overlap between BXXXT nodes and disease nodes was observed at each level, and the network-based proximity analysis shows that the relevance between the formula targets and disease genes was significant according to the shortest path distance (SPD) and a random walk with restart (RWR) based scores for each disease. We found that there were 22 key pathways significantly associated with BXXXT, and the therapeutic effects of BXXXT were likely addressed by regulating a combination of targets in a modular pattern. Furthermore, the synergistic effects among BXXXT herbs were highlighted by elucidating the molecular mechanisms of individual herbs, and the traditional theory of "Jun-Chen-Zuo-Shi" of TCM formula was effectively interpreted from a network perspective. The proposed approach provides an effective strategy to uncover the mechanisms of action and combinatorial rules of BXXXT formula in a holistic manner.

Licorice ethanol extract improves symptoms of polycytic ovary syndrome in Letrozole-induced female rats

BACKGROUND

Licorice (Glycyrrhizae radix et rhizome, GRR) has long been used as an ingredient in Korean traditional medicinal herbal formulas for various metabolic and reproductive diseases. Polycystic ovary syndrome (PCOS) is a common endocrine disorder in premenopausal women. In the present study, we examined the effects of GRR extract on PCOS-like symptoms in female rats.

METHODS

Symptoms of PCOS were induced by Letrozole treatment for 4 weeks in 6-week-old female SD rats, after which the effects of GRR extract on recovery of normal hormonal levels and polycystic ovaries were assessed. Serum levels of luteinizing hormone (LH), follicular-stimulating hormone (FSH), LH/FSH ratio, and follicular cysts were evaluated, followed by the expression levels of known follicular phase markers such as Kitl, Cyp11a1, and Ptgs2.

RESULTS

The serum level of FSH was reduced only in the Lestrozole treatment group (PCOS), whereas significant recovery of FSH level was observed in the Letrozole and GRR co-treatment group (PCOS + GRR). Serum LH levels were not altered in any of the groups. Furthermore, the LH/FSH ratio (known biomarker for PCOS) was elevated only in the Letrozole treatment group (PCOS), whereas it was significantly reduced in the Letrozole and GRR co-treatment group (PCOS + GRR). For histological changes, follicular cysts, antral follicles, and increased thickness of the theca- and granulosa layers were observed in the PCOS group, whereas these alterations were remarkably reversed by GRR treatment.

CONCLUSION

These results suggest that GRR extract inhibits the symptoms of PCOS by regulating imbalanced hormonal levels and irregular ovarian follicles.

The impact of probiotics' administration on glycemic control, body composition, gut microbiome, mitochondria, and other hormonal signals in adolescents with prediabetes - A randomized, controlled trial study protocol

BACKGROUND

Recent studies have demonstrated that a significant proportion of adolescents exhibit abdominal obesity in early-middle adolescence, and impaired glucose metabolism. Dysregulation of glucose metabolism is aggravated by the existing osteosarcopenia not only in obese but also in overweight youth. Biochemical inflammation, derived from glucose metabolism dysregulation, in combination with increased stress levels lead to the accumulation of reactive oxygen species, also known as ROS, which seem to afflict the integrity of the gastrointestinal wall, gut mucosa, and commensal, intestinal gut microflora. The current scientific protocol aims to assess the administration of probiotics in prediabetic adolescents in relation with their glycemic control, body composition, and intestinal microbiome.

METHODS/DESIGN

This is a study protocol of a two-armed RCT, that recruits adolescents with prediabetes, who will receive either a 4-month, life-style intervention, or a life-style intervention along with a probiotic supplement. The primary outcome is the differences in gut microbiome synthesis, body composition analysis parameters, and concentrations of hormones, before and after the intervention.

DISCUSSION

This study aims to halt the progression of obesity and diabetes and aspires to contribute new evidence for upgraded treatment of obesity and diabetes.

TRIAL REGISTRATION

Australian New Zealand Clinical Trial Registry (ACTRN12615000470594).

Chemical Fingerprinting and Quantification of Chinese Cinnamomi Cortex by Ultra High Performance Liquid Chromatography Coupled with Chemometrics Methods

To rapidly clarify and quantify the chemical profiling of Cinnamomi cortex a reliable and feasible strategy of chromatographic fingerprinting with a suite of chemometrics methods was developed and validated by ultra-high performance liquid chromatography coupled with diode array detection. Furthermore, to identify more meaningful chemical markers, the chemometrics methods including hierarchical cluster analysis (HCA), principal component analysis (PCA) and similarity, which all generate quality evaluations and correlation classifications of Cinnamomi cortex, were used to improve the Cinnamomi cortex quality control standards. A total of 12 characteristic peaks were confirmed, seven of which were identified by comparing their retention times, UV and MS spectra with authentic compounds. Moreover, 11 analytes were accurately determined, as a complementary quantification method of chromatographic fingerprinting. For quantitative analyses, selective detection was performed at 254, 280 and 340 nm. The tested samples were separated and determined using UPLC and a series of methodologies including linearity, precision, accuracy, limit of detection and quantification and extraction recoveries were validated. Meanwhile the method bias for all the analytes did not exceed 5%. A total of 42 samples were acquired in China and analyzed. The results demonstrated that chromatographic fingerprinting in combination with chemometrics methods provides a promising and practical method to more effectively and comprehensively control the quality of Cinnamomi cortex from various sources, which would be a useful reference for the development and further study of Cinnamomi cortex and related formulations.

The Pathogenesis of Diabetes Mellitus by Oxidative Stress and Inflammation: Its Inhibition by Berberine

A substantial knowledge on the pathogenesis of diabetes mellitus (DM) by oxidative stress and inflammation is available. Berberine is a biologically active botanical that can combat oxidative stress and inflammation and thus ameliorate DM, especially type 2 DM. This article describes the potential of berberine against oxidative stress and inflammation with special emphasis on its mechanistic aspects. In diabetic animal studies, the modified levels of proinflammatory cytokines and oxidative stress markers were observed after administering berberine. In renal, fat, hepatic, pancreatic and several others tissues, berberine-mediated suppression of oxidative stress and inflammation was noted. Berberine acted against oxidative stress and inflammation through a very complex mechanism consisting of several kinases and signaling pathways involving various factors, including NF-κB (nuclear factor-κB) and AMPK (AMP-activated protein kinases). Moreover, MAPKs (mitogen-activated protein kinases) and Nrf2 (nuclear factor erythroid-2 related factor 2) also have mechanistic involvement in oxidative stress and inflammation. In spite of above advancements, the mechanistic aspects of the inhibitory role of berberine against oxidative stress and inflammation in diabetes mellitus still necessitate additional molecular studies. These studies will be useful to examine the new prospects of natural moieties against DM.

Tetrandrine alleviates symptoms of rheumatoid arthritis in rats by regulating the expression of cyclooxygenase-2 and inflammatory factors

The present study aimed to construct a rat model of rheumatoid arthritis (RA) to evaluate changes in pathology, the expression of inflammatory factors and regulation of signaling pathways. The protective effect of tetrandrine (Tet) on tissue lesions induced by RA was also investigated. A total of 60 Wistar rats (100-200 g) were randomly divided into six groups (n=10 per group), namely a blank (NC) group, model group, methotrexate (MTX) group (3 mg/kg body weight), high-dose Tet group (31.25 mg/kg body weight), medium-dose Tet group (18.75 mg/kg body weight) and low-dose Tet group (6.25 mg/kg body weight). A rat model of RA was induced via injection of 0.1 ml complete Freund's adjuvant into the right rear toe. Toe swelling rate, arthritis index and immune organ index were calculated. In addition, cyclooxygenase (COX)-2 expression at the mRNA and protein level in the peripheral blood mononuclear cells (PBMCs) of rats were determined by reverse transcription-quantitative polymerase chain reaction and western blot analysis, respectively. Serum concentrations of inflammatory factors were measured using enzyme-linked immunosorbent assays. It was observed that treatment with Tet alleviated the severity of rear toe swelling associated with RA in rats. Furthermore, Tet exerted anti-inflammatory and immunosuppressive effects in the rat model of RA. Tet also reduced the expression of COX-2 in PBMCs and lowered the concentrations of inflammatory factors in the serum of RA rats. The present data indicate that Tet may exert pharmacological effects in the treatment of RA. The mechanism of action of Tet may be associated with the regulation of inflammatory factors and the inhibition of immune organs.

A 42-Markers Pharmacokinetic Study Reveals Interactions of Berberine and Glycyrrhizic Acid in the Anti-diabetic Chinese Medicine Formula Gegen-Qinlian Decoction

Herbal medicines are commonly used as compound formulas in clinical practice to achieve optimal therapeutic effects. However, the combination mechanisms usually lack solid evidence. In this study, we report synergistic interactions through altering pharmacokinetics in Gegen-Qinlian Decoction (GQD), an anti-diabetic Chinese medicine formula. A multi-component pharmacokinetic study of GQD and the single herbs was conducted by simultaneously monitoring 42 major bioactive compounds (markers) in rats plasma using LC/MS/MS within 30 min. GQD could remarkably improve the plasma concentrations of berberine (BER) and other alkaloids in Huang-Lian by at least 30%, and glycyrrhizic acid (GLY) from Gan-Cao played a major role. A Caco-2 cell monolayer test indicated that GLY improved the permeability of BER by inhibiting P-glycoprotein. Although GLY alone did not show observable effects, the co-administration of GLY (ig, 50 or 80 mg/kg) could improve the anti-diabetic effects of berberine (ig, 50 mg/kg) in db/db mice in a dose-dependent manner. The blood glucose decreased by 46.9%, whereas the insulin level increased by 40.8% compared to the control group. This is one of the most systematic studies on the pharmacokinetics of Chinese medicine formulas, and the results demonstrate the significance of pharmacokinetic study in elucidating the combination mechanisms of compound formulas.

Yellow Tongue Coating is Associated With Diabetes Mellitus Among Japanese Non-smoking Men and Women: The Toon Health Study

BACKGROUND

Yellow tongue coating is one of the clinical signs for diabetes mellitus according to traditional East Asian medicine. Few reports have been available on the association between yellow tongue coating and the prevalence of type 2 diabetes in the general population. We examined that association among population samples of non-smoking men and women.

METHODS

The study subjects were Japanese non-smoking men (n = 315) and women (n = 654) aged 30-79 years who resided in Toon city and participated in the Toon Health Study from July 2011 through November 2014. Tongue coating was assessed by a nationally licensed acupuncturist and classified into three categories of white (normal), light yellow, and yellow. We performed an oral glucose tolerance test to confirm the presence of diabetes mellitus and prediabetes. The associations between yellow tongue coating and the prevalence of diabetes mellitus and prediabetes were examined using multivariable logistic regression analyses, adjusting for age, sex, body mass index, drinking status, and physical activity.

RESULTS

The multivariable odds ratios of diabetes mellitus were 1.39 (95% confidence interval [CI], 0.72-2.67) for light yellow tongue coating and 2.23 (95% CI, 1.16-4.30) for yellow tongue coating compared with white tongue coating. The respective multivariable odds ratios of prediabetes were 1.13 (95% CI, 0.80-1.61) and 1.43 (95% CI, 0.96-2.12).

CONCLUSIONS

Yellow tongue coating was associated with higher prevalence of diabetes mellitus and tended to be associated with that of prediabetes among Japanese non-smoking men and women.

Characteristics and Antioxidant Activity of Lignans in Schisandra chinensis and Schisandra sphenanthera from Different Locations

Twenty Schisandra samples were collected from different locations. Contents of 7 lignans in the samples were determined and analyzed by HPLC method coupled with hierarchical clustering analysis (HCA) and principal component analysis (PCA), and the antioxidant capacity of Schisandra from the different locations was evaluated by reducing power, ferric thiocyanate (FTC) and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) assay. The results showed that there was a significant difference in the content of lignans between Schisandra chinensis and Schisandra sphenanthera. The Schisandra sphenanthera samples in the southwest of China were significantly different from those from the other locations. The antioxidant capacity of Schisandra chinensis was significantly superior to that of Schisandra sphenanthera, and the main antioxidant components were schisandrol A, schisandrol B and schisandrin B based on the result of discrimination analyses. The differences in the chemical composition and antioxidant activity of lignans in Schisandra chinensis and Schisandra sphenanthera from the different locations were investigated in this study, which may provide an experimental basis for the quality control of Schisandra.

Estimated daily quercetin intake and association with the prevalence of type 2 diabetes mellitus in Chinese adults

PURPOSE

Quercetin is one of potential antidiabetic substances because of its powerful antioxidant and anti-inflammatory actions. The purpose of this study is to estimate daily quercetin intake and assess the relationship between dietary quercetin intake and the prevalence of type 2 diabetes mellitus (T2DM) in a Chinese population.

METHODS

Dietary intake was investigated by a validated 100-item food frequency questionnaire. Daily intakes of quercetin and nutrients were calculated accordingly. T2DM was diagnosed based on the criteria of the American Diabetes Association. Adjusted logistic regression models were used to analyze the relationship between the quartiles of quercetin intake and the prevalence of T2DM.

RESULTS

The prevalences of T2DM were 8.35% in men and 4.68% in women. The main food sources of quercetin were apple, orange, and green tea. Daily intake of quercetin was 20.9 ± 2.32 mg/day (mean ± SD). After adjusting for potentially confounding factors, the odds ratios (95% CI) for T2DM across the ascending quartiles of quercetin intake were: 1.00 (reference), 0.75 (0.60-0.95), 0.76 (0.59-0.99), and 0.63 (0.51-0.94).

CONCLUSIONS

The results of the present study showed that quercetin intake was inversely related to the prevalence of T2DM in the Chinese population, suggesting a protective effect of quercetin in the development of T2DM.

Antidiabetic Activity and Chemical Composition of Sanbai Melon Seed Oil

Objectives

Many fruits and herbs had been used in Traditional Chinese Medicines for treating diabetes mellitus (DM); however, scientific and accurate evidences regarding their efficacy and possible mechanisms were largely unknown. Sanbai melon seed oil (SMSO) was used in folk medicine in treating DM, but there is no literature about these effects. The present study was aimed at confirming the treatment effects of SMSO in type 1 DM.

Methods

Diabetes was induced by single intraperitoneal injection of streptozotocin (STZ) at a dose of 65 mg/kg body weight. After diabetes induction, mice were treated with SMSO at dose of 1 g/kg, 2 g/kg, and 4 g/kg. Drugs were given by gavage administration once a day continuously for 28 days. At the end of treatment, several biochemical parameters and molecular mechanisms were determined by biochemical assays, ELISA, and Western blotting. The chemical compositions of SMSO were also tested.

Results

SMSO treatment significantly improved the symptoms of weight loss, polydipsia, reduced FBG level, increased plasma insulin levels, reduced plasma lipids levels, and protected islet injury. The results also showed that SMSO mitigated oxidative stress and alleviated the liver and renal injury in diabetes mice. SMSO also protected islet cells from apoptotic damage by suppressing ER mediated and mitochondrial dependent apoptotic pathways. Further constituent analysis results showed that SMSO had rich natural resources which had beneficial effects on DM.

Conclusions

This study showed that SMSO had excellent antidiabetes effect and provided scientific basis for the use of SMSO as the functional ingredients production and dietary supplements production in the food and pharmaceutical industries.

Natural products for the treatment of type 2 diabetes mellitus: Pharmacology and mechanisms

Epidemiological studies have implied that diabetes mellitus (DM) will become an epidemic accompany with metabolic and endocrine disorders worldwide. Most of DM patients are affected by type 2 diabetes mellitus (T2DM) with insulin resistance and insulin secretion defect. Generally, the strategies to treat T2DM are diet control, moderate exercise, hypoglycemic and lipid-lowing agents. Despite the therapeutic benefits for the treatment of T2DM, most of the drugs can produce some undesirable side effects. Considering the pathogenesis of T2DM, natural products (NPs) have become the important resources of bioactive agents for anti-T2DM drug discovery. Recently, more and more natural components have been elucidated to possess anti-T2DM properties, and many efforts have been carried out to elucidate the possible mechanisms. The aim of this paper was to overview the activities and underlying mechanisms of NPs against T2DM. Developments of anti-T2DM agents will be greatly promoted with the increasing comprehensions of NPs for their multiple regulating effects on various targets and signal pathways.

Canagliflozin exerts anti-inflammatory effects by inhibiting intracellular glucose metabolism and promoting autophagy in immune cells

Canagliflozin (CAN) regulates intracellular glucose metabolism by targeting sodium-glucose co-transporter 2 (SGLT2) and intracellular glucose metabolism affects inflammation. In this study, we hypothesized that CAN might exert anti-inflammatory effects. The anti-inflammatory effects and action mechanisms of CAN were assayed in lipopolysaccharide (LPS)-induced RAW264.7 and THP-1 cells and NIH mice. Results showed that CAN significantly inhibited the production and release of interleukin (IL)-1, IL-6, or tumor necrosis factor-α (TNF-α) in the LPS-induced RAW264.7 and THP-1 cells, and mice. CAN also significantly inhibited intracellular glucose metabolism and 6-phosphofructo-2-kinase (PFK2) expression. CAN increased the levels of sequestosome-1 (SQSTM1/p62), upregulated the ratios of microtubule-associated protein 1A/1B-light chain 3 (LC3) II to I, promoted the formation of LC3 puncta, and enhanced the activities of lysosome. The inhibition of autophagy by 3-methyladenine (3-MA) reversed the effects of CAN on IL-1α levels. Increased autophagy might be associated with increased AMP-activated protein kinase (AMPK) phosphorylation. Interestingly, p62 demonstrated good co-localization with IL-1α and possibly mediated IL-1α degradation. CAN-induced increase in p62 was dependent on the nuclear factor kappa B (NFκB) signaling pathway. These results indicated that CAN might exert anti-inflammatory effects by inhibiting intracellular glucose metabolism and promoting autophagy. Attenuated glucose metabolism by PFK2, increased autophagy flow by AMPK, and increased p62 levels by NFκB might be responsible for the molecular mechanisms of CAN. This drug might serve as a new promising anti-inflammatory drug for acute or chronic inflammatory diseases via independent hypoglycemic mechanisms. This drug might also be used as an important reference for similar drug research and development by targeting intracellular glucose metabolism and autophagy in immune cells.

Different intervention strategies for preventing type 2 diabetes mellitus in China: A systematic review and network meta-analysis of randomized controlled trials

Different strategies are increasingly used for early intervention in prediabetes in China, but the effects of these strategies on incident diabetes have not yet been confirmed. The aim of the present study was to assess systematically the effects of different strategies for preventing diabetes, aimed at Chinese people with prediabetes. Seven electronic databases were searched to identify eligible trials published from inception to September 20, 2016. Randomized controlled trials with a minimum follow-up duration of 6 months were included. Standard pairwise meta-analysis with a random-effects model and network meta-analysis with a frequentist framework were performed. A total of 63 studies, including 11 intervention strategies, were included. Compared with placebo, all strategies, except for lipid-affecting drugs and sitagliptin, reduced the rate of incident diabetes with different levels of effectiveness, ranging from 0.18 (95% confidence interval [CI] 0.12, 0.27) to 0.39 (95% CI 0.20, 0.75). Ranking probability analysis indicated that metformin and β-cell-stimulating drugs reduced the risk of diabetes most, with probabilities of 87.4% and 81%, respectively. Ethnicity and cultural factors should be considered for diabetes prevention. Most of the included trials were of poor methodological quality, however, and the results should be interpreted with caution.

Recent advances and effective strategies in the discovery and applications of natural products

Natural products are the most representative form of conventional therapy as compared to any other traditional or alternative medicine systems.

Improved cell membrane bioaffinity sample pretreatment technique with enhanced stability for screening of potential allergenic components from traditional Chinese medicine injections

Aiming at improving reliability in conventional cell membrane chromatography, an improved bioaffinity sample pretreatment technique with enhanced stability was developed to fast screen and extract potential allergenic components from traditional Chinese medicine injections.

Metformin and cancer: An existing drug for cancer prevention and therapy

Metformin is a standard clinical drug used to treat type 2 diabetes mellitus (T2DM) and polycystic ovary syndrome. Recently, epidemiological studies and meta-analyses have revealed that patients with T2DM have a lower incidence of tumor development than healthy controls and that patients diagnosed with cancer have a lower risk of mortality when treated with metformin, demonstrating an association between metformin and tumorigenesis. In vivo and in vitro studies have revealed that metformin has a direct antitumor effect, which may depress tumor proliferation and induce the apoptosis, autophagy and cell cycle arrest of tumor cells. The mechanism underpinning the antitumor effect of metformin has not been well established. Studies have demonstrated that reducing insulin and insulin-like growth factor levels in the peripheral blood circulation may lead to the inhibition of phosphoinositide 3-kinase/Akt/mechanistic target of rapamycin (mTOR) signaling or activation of AMP-activated protein kinase, which inhibits mTOR signaling, a process that may be associated with the antitumor effect of metformin. The present review primarily focuses on the recent progress in understanding the function of metformin in tumor development.

Tangshen formula improves inflammation in renal tissue of diabetic nephropathy through SIRT1/NF-κB pathway

The present study investigated the mechanism underlying the anti-inflammatory effects of Tangshen formula (TS) in Sprague Dawley (SD) rats with diabetic nephropathy (DN). A rat model of DN was established by intraperitoneal injection of 1% (40 mg/kg) streptozotocin and administration of a high fat and glucose diet. Subsequently, SD rats were randomly divided into six groups (n=8): A DN group, a valsartan group, a high-dose TS group, a middle-dose TS group, a low-dose TS group and a control group with normal SD rats. Once rats received their allocated treatment for 12 weeks, body weight and kidney weight were recorded, and fasting blood glucose, ratio of urinary protein, β₂-MG and creatinine clearance rate were determined. Furthermore, hemodynamic indices, including plasma viscosity and whole blood reduction viscosity were detected. Immunohistochemistry was used to detect the infiltration of macrophages in the kidneys of rats. Reverse transcription-quantitative polymerase chain reaction and western blotting were performed to investigate the activation; mRNA and protein expression levels of monocyte chemoattractant protein-1 (MCP-1), macrophage migration inhibitory factor (MIF), nuclear factor-κB (NF-κB) and sirtuin-1 (SIRT1) in each group. In comparison with the DN group, each biochemical indicator of rats in the high-dose TS group was significantly decreased (P<0.05). Blood viscosity in each treatment group was significantly decreased when compared with the DN group (P<0.01). Hematoxylin and eosin staining indicated that the infiltration of macrophages was significantly decreased in the high-dose TS group when compared with the DN group (P<0.01). mRNA and protein expression levels of MCP-1 and MIF in the high-dose TS group were significantly decreased when compared with the DN group (P<0.05). In the treatment groups, SITR1 mRNA expression levels were significantly increased, whereas the mRNA expression levels of NF-κB were significantly decreased (P<0.01). Western blotting results indicated a significant decrease in the protein expression levels of acetylated NF-κB in the treatment groups when compared with the DN group (P<0.01) and the propensity of protein expression of the other inflammatory factors were consistent with the mRNA findings. The results of the high-dose TS group were similar to those of the valsartan group. The present study indicates that TS was able to activate SITR1, which lead to NF-κB deacetylation, thus reducing the release of inflammatory factors and decreasing the severity of diabetic nephropathy.

Comparison of Goto-Kakizaki rats and high fat diet-induced obese rats: Are they reliable models to study Type 2 Diabetes mellitus?

Type 2 Diabetes mellitus (T2DM) is an evident growing disease that affects different cultures throughout the world. T2DM occurs under the influence of three main factors: the genetic background, environmental and behavioral components. Obesity is strongly associated to the development of T2DM in the occident, while in the orient most of the diabetic patients are considered lean. Genetics may be a key factor in the development of T2DM in societies where obesity is not a recurrent public health problem. Herein, two different models of rats were used to understand their differences and reliability as experimental models to study the pathophysiology of T2DM, in two different approaches: the genetic (GK rats) and the environmental (HFD-induced obese rats) influences. GK rats were resistant to weight gain even though food/energy consumption (relative to body weight) was higher in this group. HFD, on the other hand, induced obesity in Wistar rats. White adipose tissue (WAT) expansion in this group was accompanied by immune cells infiltration, inflammation and insulin resistance. GK rats also presented WAT inflammation and insulin resistance; however, no immune cells infiltration was observed in the WAT of this group. Liver of HFD group presented fat accumulation without differences in inflammatory cytokines content, while liver of GK rats didn't present fat accumulation, but showed an increase of IL-6 and IL-10 content and glycogen. Also, GK rats showed increased plasma GOT and GPT. Soleus muscle of HFD presented normal insulin signaling, contrary to GK rats, which presented higher content of basal phosphorylation of GSK-3β. Our results demonstrated that HFD developed a mild insulin resistance in Wistar rats, but was not sufficient to develop T2DM. In contrast, GK rats presented all the typical hallmarks of T2DM, such as insulin resistance, defective insulin production, fasting hyperglycemia/hyperinsulinemia and lipid plasma alteration. Thus, on the given time point of this study, we may conclude that only GK rats shown to be a reliable model to study T2DM.

Strigolactones: a plant phytohormone as novel anti-inflammatory agents

Strigolactones (SLs) are a novel class of plant hormones with enormous potential for the prevention and treatment of inflammation. To further investigate the anti-inflammatory activities of SLs, a representative SL, GR24, and the reductive products of its D-ring were synthesized and their anti-inflammatory activities were fully evaluated on both in vitro and in vivo models. Among these compounds, the two most active optical isomers (2a and 6a) demonstrated strong inhibitory activity on the release of inflammatory cytokines, including nitric oxide (NO), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) by blocking the nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways; they also greatly inhibited the migration of neutrophils and macrophages in fluorescent protein labeled zebrafish larvae. These results identified the promising anti-inflammatory effects of SLs, and suggested that both the absolute configuration of SL and the α,β-unsaturated D-ring structure are essential for the observed anti-inflammatory activity.

Quercetin nanoparticle complex attenuated diabetic nephropathy via regulating the expression level of ICAM-1 on endothelium

The purpose of the study was to reveal the therapeutic effect of quercetin (QUE) nanoparticle complex on diabetic nephropathy (DN) by regulating the expression of intercellular adhesion molecular-1 (ICAM-1) on endothelium as compared to free QUE. QUE 10 mg/kg as a single abdominal subcutaneous injection daily for 8 weeks continuously in diabetic rats and 10 mg/kg QUE nanoparticle complex as a single abdominal subcutaneous injection every 5 days, continuously administered for 8 weeks to diabetic rats. Blood and left kidneys were collected; pathological change of kidney, renal function, oxidative stress level, blood glucose level, serum lipid, urine protein, and albumin/creatinine ratio were measured; and neutrophil adhesion, ICAM-1 expression, and CD11b⁺ cells infiltration were observed. Both QUE and QUE nanoparticle complex preconditioning ameliorated the pathological damage of kidney and improved renal function, alleviated renal oxidative stress injury, restricted inflammatory cells infiltration, and downregulated the ICAM-1 expression as compared to DN group, while QUE nanoparticle complex significantly alleviated this effect.

Metabolomics study of the therapeutic mechanism of Schisandra Chinensis lignans in diet-induced hyperlipidemia mice

Background

Schisandra, a globally distributed plant, has been widely applied for the treatment of diseases such as hyperlipidemia, fatty liver and obesity in China. In the present work, a rapid resolution liquid chromatography coupled with quadruple-time-of-flight mass spectrometry (RRLC-Q-TOF-MS)-based metabolomics was conducted to investigate the intervention effect of Schisandra chinensis lignans (SCL) on hyperlipidemia mice induced by high-fat diet (HFD).

Methods

Hyperlipidemia mice were orally administered with SCL (100 mg/kg) once a day for 4 weeks. Serum biochemistry assay of triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c) and high-density lipoprotein cholesterol (HDL-c) was conducted to confirm the treatment of SCL on lipid regulation. Metabolomics analysis on serum samples was carried out, and principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) were carried out for the pattern recognition and characteristic metabolites identification. The relative levels of critical regulatory factors of liver lipid metabolism, sterol regulatory element-binding proteins (SREBPs) and its related gene expressions were measured by quantitative real-time polymerase chain reaction (RT-PCR) for investigating the underlying mechanism.

Results

Oral administration of SCL significantly decreased the serum levels of TC, TG and LDL-c and increased the serum level of HDL-c in the hyperlipidemia mice, and no effect of SCL on blood lipid levels was observed in control mice. Serum samples were scattered in the PCA scores plots in response to the control, HFD and SCL group. Totally, thirteen biomarkers were identified and nine of them were recovered to the normal levels after SCL treatment. Based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analysis, the anti-hyperlipidemia mechanisms of SCL may be involved in the following metabolic pathways: tricarboxylic acid (TCA) cycle, synthesis of ketone body and cholesterol, choline metabolism and fatty acid metabolism. Meanwhile, SCL significantly inhibited the mRNA expression level of hepatic lipogenesis genes such as SREBP-1c, fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC), and decreased the mRNA expression of liver X receptor α (LXRα). Moreover, SCL also significantly decreased the expression level of SREBP-2 and 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR) in the liver of hyperlipidemia mice.

Conclusion

Anti-hyperlipidemia effect of SCL was confirmed by both serum biochemistry and metabolomics analysis. The mechanism may be related to the down-regulation of LXRα/SREBP-1c/FAS/ACC and SREBP2/HMGCR signaling pathways.

Trigonelline Inhibits Inflammation and Protects β Cells to Prevent Fetal Growth Restriction during Pregnancy in a Mouse Model of Diabetes

Background: As an active component from traditional Chinese medicine, trigonelline has a protective effect on diabetes. This study evaluated the protective effects of trigonelline on diabetic mice during pregnancy. Methods: Diabetes was induced in female mice by intraperitoneal injection for continuous 5-day of 40 mg/kg/day streptozotocin. Female mice were divided into 4 groups after they were allowed to mate with normal male mice: nondiabetic, nondiabetic treated with trigonelline (70 mg/kg) for 18 days, diabetic, and diabetic treated with trigonelline (70 mg/kg). Results: Diabetic pregnant mice had significantly higher levels of blood glucose, serum total cholesterol, triglyceride, insulin, and leptin but lower serum omentin-1 level and insulin sensitivity index than the nondiabetic ones. Trigonelline improved the hyperglycemia, dyslipidemia, insulin resistance, and adipocytokine of diabetic pregnant mice. Diabetic pregnant mice had significantly reduced fetus numbers, fetal weight, and fetal/placental ratio, which were reversed by trigonelline. Trigonelline prevented the increase in proinflammatory cytokines and reduced interleukin-10 level in placenta of diabetic pregnant mice. Trigonelline increased β-cell replication and the decreased β-cell mass, and decreased the β-cell apoptosis of diabetic pregnant mice. Conclusion: These findings suggest that trigonelline protects diabetic pregnancy partly by suppressing inflammation, regulating the secretion of adipocytokines, increasing β-cell mass, replication, and decreasing β-cell apoptosis.

MiR-30a targets IL-1α and regulates islet functions as an inflammation buffer and response factor

Diabetes is an inflammatory disease. Inflammation plays an important role in islet functions. However, the exact mechanisms by which inflammation affects islet functions remain unclear. In this study, we investigated the regulatory effects of miR-30a on inflammation and islet functions. The results indicate that miR-30a serves as an inflammation-resolving buffer factor by targeting interleukin 1a (IL-1α) in immune cells and in islet cells, which might play an important role in inflammation homeostasis. miR-30a ameliorates islet functions in an inflammatory micro-environment by targeting the IL-1α/nuclear factor kappa B (NFKB) p65 subunit (p65)/p62 (SQSTM1)/insulin axis, which can be developed into a novel antidiabetic approach. miR-30a serves as a promising inflammation-response biomarker in inflammatory diseases and is possibly activated by the toll-like receptor 4 (TLR4)/IL-1α/NFKB pathways. However, the exact molecular mechanisms by which miR-30a regulates inflammation and islet functions as well as the potential applications in transitional medicine require further elucidation.

The Effect of Dried Glycyrrhiza Glabra L. Extract on Obesity Management with Regard to PPAR-γ2 (Pro12Ala) Gene Polymorphism in Obese Subjects Following an Energy Restricted Diet

Purpose: Obesity is a multi-factorial health problem which results from the interaction of environmental and genetic factors. The aim of the present study was to determine the effects of dried licorice extract with a calorie restricted diet on anthropometric indices and insulin resistance with nutrigenetic approach. Methods: For this pilot, double-blind, placebo-controlled randomized clinical trial, 72 eligible subjects were randomly allocated to Licorice or placebo group. They received a low-calorie diet either with a 1.5 g/day of Licorice extract or placebo for 8 weeks. Results: There were no significant differences in anthropometric indices and dietary intake in genotype subgroups at the baseline. Findings indicated that supplementation with Licorice extract did not change anthropometric indices and biochemical parameters significantly compared to a hypocaloric diet alone. However, from the nutrigenetic point of view, significant changes in anthropometric indices and QUICKI were observed in the Pro12Pro genotypes compared to the Pro12Ala at the end of the study (p<0.05 in all variables). Moreover, no interactive effect of the Licorice supplement and Pro12Ala genotype was found. Conclusion: In obese subjects, the Pro/Pro polymorphism of the PPAR-γ2 gene seems to induce favourable effects on obesity management. Further studies are needed to clarify whether PPAR-γ2 gene polymorphisms or other obesity genes can affect responses to obesity treatment.

Copaiba oil-resin (Copaifera reticulata Ducke) modulates the inflammation in a model of injury to rats' tongues

Background

The regeneration of integrity and tissue homeostasis after injury is a fundamental property and involves complex biological processes fully dynamic and interconnected. Although there are medications prescribed to accelerate the process of wound healing by reducing the exaggerated inflammatory response, comes the need to search for different compounds of Amazonian biodiversity that can contribute to the acceleration of the healing process. Among these products, the copaiba oil-resin is one of the most prominent feature in this scenario, as they have been reported its medicinal properties.

Methods

Aiming to evaluate the anti-inflammatory and healing effect of copaiba oil-resin (Copaifera reticulata Ducke) in transfixing injury of rats’ tongues first proceeded up the copaiba oil-resin oral toxicity test in 5 male mice to stipulate the therapeutic dose which was established at 200 mg/kg/day. Then it was induced transfixing injury in a total of 15 Wistar rats. The animals were randomly divided into three groups based on the treatment: control group, dexamethasone group and copaiba oil-resin group. After 7 days of treatment, histological slides stained with hematoxylin and eosin was prepared. Immunohistochemistry for CD68 (macrophage marker) was performed and analyzed by the cell counter Image J.

Results

The acute toxicity test showed that the oil-resin copal has low toxicity. Furthermore, copaiba oil-resin therapy modulates the inflammatory response by decreasing the chronic inflammatory infiltrate, edema and specifically the number of macrophages.

Conclusions

The results indicate the potential of the Amazon region and showed up relevant because therapy with this extract modulates the inflammatory process.

EFFECT OF ASTRAGALOSIDE ON VITAMIN D-RECEPTOR EXPRESSION AFTER ENDOTHELIN-1-INDUCED CARDIOMYOCYTE INJURY

BACKGROUND

Astragaloside, which is one of the main components of Astragalus membranaceus, has been widely used in the treatment of congestive heart failure in China, and it can protect cardiomyocytes. Its mechanism of action remains unclear. Therefore, the present study was carried out to investigate the influence of astragaloside on rat cardiomyocytes stimulated with endothelin-1 (ET-1), and explored the underlying mechanism.

MATERIALS AND METHODS

ET-1 was used to stimulate primary rat cardiomyocytes and establish a cardiomyocyte hypertrophy model. Different astragaloside doses were administered in combination with ET-1. Cardiomyocyte hypertrophy and apoptosis were examined using transmission electron microscopy (TEM) and flow cytometry, respectively. The molecular mechanism was explored by analyzing the mRNA of the vitamin D receptor (VDR), cytochrome P450 family 27 subfamily B member 1(CYP27B), cytochrome P450 family 24 subfamily A member 1(CYP24A) and renin mRNA levels by quantificational real-time polymerase chain reaction(qRT-PCR).

RESULTS

Rat cardiomyocyte hypertrophy model was established successfully. Astragaloside administration significantly affected cell apoptosis and significantly inhibited ET-1-induced cardiomyocyte hypertrophy in a dose-dependent manner. Astragaloside treatment affected the expression of signaling molecules in the vitamin D axis.

CONCLUSION

Astragaloside inhibits ET-1-induced cardiomyocyte hypertrophy. This effect can be reversed by regulating the levels of the relevant factors in the vitamin D axis.

Effects of puerarin on intracellular Ca2+ and cell viability of MDCK renal tubular cells

Puerarin is a natural compound and has been used as herb medication in a number of countries, especially in Asia. The effect of puerarin on Ca²⁺ signaling is unknown in renal cells. This study examined whether puerarin affected Ca²⁺ physiology in MDCK renal tubular cells. Cytosolic free Ca²⁺ levels ([Ca²⁺]_i) were measured using the fluorescent dye fura-2. Cell viability was examined by using WST-1 assay. Puerarin induced [Ca²⁺]_i rises and the response was reduced by removing extracellular Ca²⁺. Puerarin-induced Ca²⁺ entry was not altered by protein kinase C (PKC) activity, but was inhibited by nifedipine. In Ca²⁺-free medium, treatment with the endoplasmic reticulum Ca²⁺ pump inhibitor 2,5-di-tert-butylhydroquinone (BHQ) or thapsigargin partly inhibited puerarin-evoked [Ca²⁺]_i rises. Inhibition of phospholipase C (PLC) with U73122 did not change puerarin-induced [Ca²⁺]_i rises. Puerarin at 25-50μM caused cytotoxicity, which was not reversed by pretreatment with the Ca²⁺ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester (BAPTA/AM). Collectively, in MDCK cells, puerarin induced [Ca²⁺]_i rises by evoking PLC-independent Ca²⁺ release from the endoplasmic reticulum and other unknown stores, and Ca²⁺ entry via nifedipine-sensitive, PKC-insensitive Ca²⁺ entry pathways. Puerarin also caused Ca²⁺-independent cell death.

Puerarin suppresses LPS-induced breast cancer cell migration, invasion and adhesion by blockage NF-κB and Erk pathway

BACKGROUND

Chronic inflammation is a major risk factor for the development and metastatic progression of breast cancer. Puerarin has long been used as traditional Chinese medicine, which possesses manifold physiological activities, including anti-inflammation and anti-cancer activities. However, its anti-cancer metastasis activity in breast cancer cell inflammation-mediated have not been studied.

METHODS

Cell viability was detected with Cell Counting Kit (CCK)-8. Transwell migration and invasion assay were performed to evaluate cell migration and invasion, respectively. Enzyme-linked immunosorbent assay (ELISA) was conducted to analysis the expression of inflammatory factor. In addition, mRNA and protein levels of related cytokines were determined by qRT- PCR assay and western blot analysis, respectively.

RESULTS

In this study, puerarin significantly inhibited lipopolysaccharide (LPS)-induced MCF-7 and MDA-MB-231 cell migration, invasion and adhesion. The mRNA and protein levels revealed that puerarin treatment effectively negated the expression of CCR7, CXCR4, MMP-2, MMP-9, ICAM and VCAM in LPS- activated MCF-7 and MDA-MB-231 cells. Further, the expression of inflammatory factor TNF-α and IL-6 in cell culture supernatant remarkably reduced. Finally, the result indicated that puerarin abrogated the NF-κB activation in breast cancer cells stimulated by LPS, which is mediated through inhibition of phosphorylation of p65 and IκBα. Also, puerarin inhibited phosphorylation of Erk in breast cancer cells LPS-induced.

CONCLUSIONS

This present study revealed that puerarin might be a novel therapeutic drug for breast cancer treatment.

Jiangtang decoction ameliorate diabetic nephropathy through the regulation of PI3K/Akt-mediated NF-κB pathways in KK-Ay mice

Background

Jiangtang decoction (JTD) is a China patented drug which contains Euphorbia humifusa Willd, Salvia miltiorrhiza Bunge, Astragalus mongholicus Bunge, Anemarrhena asphodeloides Bunge, and Coptis chinensis Franch. For decades, it has also been used clinically to treat diabetic nephropathy (DN) effectively; however, the associated mechanisms remain unknown. Thus, the present study aimed to examine the protective efficacy of JTD in DN and elucidate the underlying molecular mechanisms.

Methods

A diabetic model using KK-Ay mice received a daily administration of JTD for 12 weeks. Body weight, blood glucose, triglycerides (TGs), total cholesterol (TC), urea nitrogen (UN), creatinine (Cr), and microalbumin/urine creatinine (MA/UCREA) was measured every 4 weeks. Furthermore, on the day of the sacrifice, blood, urine, and kidneys were collected to assess renal function according to general parameters. Pathological staining was performed to evaluate the protective renal effect of JTD. In addition, the levels of inflammatory cytokines (tumor necrosis factor-α [TNF-α], interleukin [IL]-6 and intercellular adhesion molecule [ICAM]-1), insulin receptor substrate [IRS]-1, advanced glycation end products [AGEs], and receptor of glycation end products [RAGE] were assessed. Finally, the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway and involvement of nuclear factor-κB (NF-κB) was further analyzed.

Results

After 12 weeks of metformin and JTD administration, the mice exhibited a significant amelioration in glucose and lipid metabolism dysfunction, reduced morphological changes in the renal tissue, decreased urinary albumin excretion, and normalized creatinine clearance. JTD treatment also reduced the accumulation of AGEs and RAGE, up-regulated IRS-1, and increased the phosphorylation of both PI3K (p85) and Akt, indicating that the activation of the PI3K/Akt signaling pathway was involved. Additionally, JTD administration reduced the elevated levels of renal inflammatory mediators and decreased the phosphorylation of NF-κB p65.

Conclusions

These results demonstrate that JTD might reduce inflammation in DN through the PI3K/Akt and NF-κB signaling pathways.

Electronic supplementary material

The online version of this article (doi:10.1186/s13020-017-0134-0) contains supplementary material, which is available to authorized users.

Screening of a natural compound library identifies emodin, a natural compound from Rheum palmatum Linn that inhibits DPP4

Historically, Chinese herbal medicines have been widely used in the treatment of hyperglycemia, but the mechanisms underlying their effectiveness remain largely unknown. Here, we screened a compound library primarily comprised of natural compounds extracted from herbs and marine organisms. The results showed that emodin, a natural compound from Rheum palmatum Linn, inhibited DPP4 activity with an in vitro IC₅₀ of 5.76 µM without inhibiting either DPP8 or DPP9. A docking model revealed that emodin binds to DPP4 protein through Glu205 and Glu206, although with low affinity. Moreover, emodin treatment (3, 10 and 30 mg/kg, P.O.) in mice decreased plasma DPP4 activity in a dose-dependent manner. Our study suggests that emodin inhibits DPP4 activity and may represent a novel therapeutic for the treatment of type 2 diabetes.

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.

Development of a Novel Electrochemical Sensor for Determination of Matrine in Sophora flavescens

A simple and sensitive electrochemical sensor fabricated with graphene nanosheets (GNs) and a hydroxyapatite (HA) nanocomposite-modified glassy carbon electrode (GCE) was developed for the determination of matrine (MT). The as-prepared electrode (GNs/HA/GCE) was verified to outperform bare a GCE and GNs-modified electrode with increased oxidation peak currents and the decreased over-potential in the redox process of MT, indicating the great enhancement of electrocatalytic activity toward the oxidation of MT by the composite of GNs and HA. Under the optimized conditions, the oxidation peak currents were related linearly with the concentration of MT, ranging from 2 μM to 3 mM, and the detection limit (S/N = 3) was 1.2 μM. In addition, the proposed electrochemical sensor can be successfully applied in the quantitative determination of MT in Sophora flavescens extract.

Nelumbo nucifera leaves extracts inhibit mouse airway smooth muscle contraction

Background

Alkaloids extracted from lotus leaves (AELL) can relax vascular smooth muscle. However, whether AELL has a similar relaxant role on airway smooth muscle (ASM) remains unknown. This study aimed to explore the relaxant property of AELL on ASM and the underlying mechanism.

Methods

Alkaloids were extracted from dried lotus leaves using the high temperature rotary evaporation extraction method. The effects of AELL on mouse ASM tension were studied using force measuring and patch-clamp techniques.

Results

It was found that AELL inhibited the high K⁺ or acetylcholine chloride (ACh)-induced precontraction of mouse tracheal rings by 64.8 ± 2.9%, or 48.8 ± 4.7%, respectively. The inhibition was statistically significant and performed in a dose-dependent manner. Furthermore, AELL-induced smooth muscle relaxation was partially mediated by blocking voltage-dependent Ca²⁺ channels (VDCC) and non-selective cation channels (NSCC).

Conclusion

AELL, which plays a relaxant role in ASM, might be a new complementary treatment to treat abnormal contractions of the trachea and asthma.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-017-1674-7) contains supplementary material, which is available to authorized users.

Phytobioactive compound-based nanodelivery systems for the treatment of type 2 diabetes mellitus - current status

Type 2 diabetes mellitus (T2DM) is a major chronic disease that is prevalent worldwide, and it is characterized by an increase in blood glucose, disturbances in the metabolism, and alteration in insulin secretion. Nowadays, food-based therapy has become an important treatment mode for type 2 diabetes, and phytobioactive compounds have gained an increasing amount of attention to this end because they have an effect on multiple biological functions, including the sustained secretion of insulin and regeneration of pancreatic islets cells. However, the poor solubility and lower permeability of these phyto products results in a loss of bioactivity during processing and oral delivery, leading to a significant reduction in the bioavailability of phytobioactive compounds to treat T2DM. Recently, nanotechnological systems have been developed for use as various types of carrier systems to improve the delivery of bioactive compounds and thus obtain a greater bioavailability. Furthermore, carrier systems in most nanodelivery systems are highly biocompatible, with nonimmunologic behavior, a high degree of biodegradability, and greater mucoadhesive strength. Therefore, this review focuses on the various types of nanodelivery systems that can be used for phytobioactive compounds in treating T2DM with greater antidiabetic effects. There is also additional focus on improving the effects of various phytobioactive compounds through nanotechnological delivery to ensure a highly efficient treatment of type 2 diabetes.

The Role of Liuwei Dihuang Pills and Ginkgo Leaf Tablets in Treating Diabetic Complications

Objective. To observe the clinical prophylactic and therapeutic efficacy of Liuwei Dihuang Pills and Ginkgo Leaf Tablets for type 2 diabetic vascular complications. Methods. It was a randomized, double-blind and placebo-controlled clinical trial. 140 outpatients with type 2 diabetes were recruited and randomly divided into the treatment group and control group. The two groups were given basic therapy (management of blood sugar, blood pressure, etc.). Additionally, the treatment group was given Liuwei Dihuang Pills and Ginkgo Leaf Tablets, while the control group was given Liuwei Dihuang Pills and Ginkgo Leaf Tablets placebos. All subjects were followed up for consecutive 36 months and observed monthly. The clinical data as urinary microalbumin to urinary creatinine ratio (Umalb/cr), carotid intima-media thickness (IMT), diabetic nephropathy (DN) and diabetic retinopathy (DR) prevalence, cardiovascular and cerebrovascular events, blood glucose, and blood pressure were collected and analyzed statistically. Results. After 36-month treatment, the Umalb/cr level and DN and DR prevalence in treatment group were all significantly lower than control group (P < 0.05). However, the IMT level and the incidence of cardiovascular and cerebrovascular events were not significantly different between the two groups (P > 0.05). Conclusions. Liuwei Dihuang Pills and Ginkgo Leaf Tablets are beneficial to diabetic microvascular complications, while the efficacy to diabetic macrovascular complications needs more observations.

Using PG-Liposome-Based System to Enhance Puerarin Liver-Targeted Therapy for Alcohol-Induced Liver Disease

A critical issue for alcohol-induced liver disease (ALD) therapeutics is the lack of a highly efficient delivery system. In this study, a Puerarin-propylene glycol-liposome system was prepared for the purpose of targeting puerarin, an isoflavon, to the liver. Transmission electron microscope (TEM) results showed the liposomes to be spherical in shape with an average diameter of 182 nm with a polydispersity index of 0.239. The zeta potential of the particles was about -30 mV. The entrapment efficiency of puerarin was above 90%. MTT-based assay in HpeG2 cells showed no significant cytotoxicity in the presence of up to 25% concentration of the system containing 3% puerarin. In vivo performance of this system was studied in mice. Pharmacokinetics and distribution of puerarin-PG-liposome system was studied relative to puerarin solution at the same dose levels. The results show that puerarin-PG-liposome prolonged drug retention time and decreased elimination of puerarin in mice (AUC of liposome system and solution was 9.5 and 4.0 mg h L^-1, respectively). Furthermore, propylene glycol (PG)-liposome system enhanced puerarin distribution into liver and spleen, while decreasing puerarin distribution in other tissues. Overall, the puerarin-PG-liposome system showed enhanced therapeutic effect in mice with ALD.

Timosaponin B-II ameliorates scopolamine-induced cognition deficits by attenuating acetylcholinesterase activity and brain oxidative damage in mice

Timosaponin B-II (TB-II) is a main active saponin isolated from the rhizome of Anemarrhena asphodeloides Bge., which is widely used in traditional Chinese medicine. In this study, the effect of TB-II on learning and memory was investigated in a scopolamine-induced mouse model of Alzheimer's disease. The results of behavioral tests indicated that TB-II significantly increased the spontaneous alternation in the Y-maze test, and reversed the shortening of step-through latency induced by scopolamine in the passive avoidance test, showing protective effects on short-term and working memory. In the Morris water maze test, TB-II reduced the escape latency time in the training trial, and increased the swimming time in the target quadrant in the probe trial. Biochemical data demonstrated that TB-II significantly inhibited acetylcholinesterase (AChE) activity in the cerebral cortex and hippocampus of mice. Moreover, TB-II markably attenuated the reduction in glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities, and decreased malondialdehyde (MDA) levels, which are key biomarkers of brain oxidative stress. These results indicated that TB-II offers protection against scopolamine-induced deficits in learning and memory, possibly by inhibiting AChE and preventing oxidative stress damage. The findings suggested that TB-II has a potential therapeutic effect on cognitive and behavioral impairment.

Administration of Traditional Chinese Blood Circulation Activating Drugs for Microvascular Complications in Patients with Type 2 Diabetes Mellitus

Traditional Chinese medicine (TCM) is an important complementary strategy for treating diabetes mellitus (DM) in China. Traditional Chinese blood circulation activating drugs are intended to guide an overall approach to the prevention and treatment of microvascular complications of DM. The core mechanism is related to the protection of the vascular endothelium and the basement membrane. Here, we reviewed the scientific evidence underpinning the use of blood circulation activating drugs to prevent and treat DM-induced microvascular complications, including diabetic nephropathy (DN), diabetic peripheral neuropathy (DPN), and diabetic retinopathy (DR). Furthermore, we summarized the effects and mechanism of TCM on improving blood rheology, inhibiting aggregation of platelet, forming advanced glycation end products (AGEs), regulating oxidative stress, reducing blood fat, and improving lipid metabolism. The paper provides a new theoretical basis for the clinical practice of TCM in the prevention and treatment of DM and its microvascular complications.