PuRenDan alleviates type 2 diabetes mellitus symptoms by modulating the gut microbiota and its metabolites.

ETHNOPHARMACOLOGICAL RELEVANCE: PuRenDan (PRD) is a traditional Chinese medicine formula comprising five herbs that have been traditionally used to treat type 2 diabetes mellitus (T2DM). While PRD has been shown to be effective in treating T2DM in clinical and animal studies, the mechanisms by which it works on the gut microbiome and metabolites related to T2DM are not well understood. AIM OF THE STUDY: The objective of this study was to partially elucidate the mechanism of PRD in treating T2DM through analyses of the gut microbiota metagenome and metabolome. MATERIALS AND METHODS: Sprague-Dawley rats were fed high-fat diets (HFDs) and injected with low-dose streptozotocin (STZ) to replicate T2DM models. Then the therapeutic effects of PRD were evaluated by measuring clinical markers such as blood glucose, insulin resistance (IR), lipid metabolism biomarkers (total cholesterol, low-density lipoprotein, non-esterified fatty acids, and triglycerides), and inflammatory factors (tumor necrosis factor alpha, interleukin-6 [IL-6], interferon gamma, and IL-1ß). Colon contents were collected, and metagenomics, combined with ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry metabolic profiling, was performed to evaluate the effects of T2DM and PRD on gut microbiota and its metabolites in rats. Spearman analysis was used to calculate the correlation coefficient among different microbiota, clinical indices, and metabolites. RESULTS: PRD exhibited significant improvement in blood glucose and IR, and reduced serum levels of lipid metabolism biomarkers and inflammatory factors. Moreover, the diversity and abundance of gut microbiota undergo significant changes in rats with T2DM that PRD was able to reverse. The gut microbiota associated with T2DM including Rickettsiaceae bacterium 4572_127, Psychrobacter pasteurii, Parabacteroides sp. CAG409, and Paludibacter propionicigenes were identified. The gut microbiota most closely related to PRD were Prevotella sp. 10(H), Parabacteroides sp. SN4, Flavobacteriales bacterium, Bacteroides massiliensis, Alistipes indistinctus, and Ruminococcus flavefaciens. Additionally, PRD regulated the levels of gut microbiota metabolites including pantothenic acid, 1-Methylhistamine, and 1-Methylhistidine; these affected metabolites were involved in pantothenate and coenzyme A biosynthesis, histidine metabolism, and secondary bile acid biosynthesis. Correlation analysis illustrated a close relationship among gut microbiota, its metabolites, and T2DM-related indexes. CONCLUSION: Our study provides insights into the gut microbiota and its metabolites of PRD therapy for T2DM. It clarifies the role of gut microbiota and the metabolites in the pathogenesis of T2DM, highlighting the potential of PRD for the treatment of this disease.

The role of Huidouba in regulating skeletal muscle metabolic disorders in prediabetic mice through AMPK/PGC-1α/PPARα pathway.

Prediabetes is a transitional state between normal blood glucose levels and diabetes, but it is also a reversible process. At the same time, as one of the most important tissues in the human body, the metabolic disorder of skeletal muscle is closely related to prediabetes. Huidouba (HDB) is a clinically proven traditional Chinese medicine with significant effects in regulating disorders of glucose and lipid metabolism. Our study aimed to investigate the efficacy and mechanism of HDB in prediabetic model mice from the perspective of skeletal muscle. C57BL/6J mice (6 weeks old) were fed a high-fat diet (HFD) for 12 weeks to replicate the prediabetic model. Three concentrations of HDB were treated with metformin as a positive control. After administration, fasting blood glucose was measured as an indicator of glucose metabolism, as well as lipid metabolism indicators such as total triglyceride (TG), low-density lipoprotein (LDL-C), high-density lipoprotein (HDL-C), free fatty acid (FFA), and lactate dehydrogenase (LDH). Muscle fat accumulation and glycogen accumulation were observed. The protein expression levels of p-AMPK, AMPK, PGC-1α, PPAR-α, and GLUT-4 were detected. After HDB treatment, fasting blood glucose was significantly improved, and TG, LDL-C, FFA, and LDH in serum and lipid accumulation in muscle tissue were significantly reduced. In addition, HDB significantly upregulated the expression levels of p-AMPK/AMPK, PGC-1α, PPAR-α, and GLUT-4 in muscle tissue. In conclusion, HDB can alleviate the symptoms of prediabetic model mice by promoting the AMPK/PGC-1α/PPARα pathway and upregulating the expression of GLUT-4 protein.

Functional and binding studies of gallic acid showing platelet aggregation inhibitory effect as a thrombin inhibitor.

Objective: This study was devoted to identifying natural thrombin inhibitors from traditional Chinese medicine (TCM) and evaluating its biological activity in vitro and binding characteristics. Methods: A combination strategy containing molecular docking, thrombin inhibition assay, surface plasmon resonance (SPR) and molecular dynamics simulation were applied to verify the study result. Results: Gallic acid was confirmed as a direct thrombin inhibitor with IC50 of 9.07 µmol/L and showed a significant inhibitory effect on thrombin induced platelet aggregation. SPR-based binding studies demonstrated that gallic acid interacted with thrombin with a KD value of 8.29 µmol/L. Molecular dynamics and binding free energy analysis revealed that thrombin-gallic acid system attained equilibrium rapidly with very low fluctuations, the calculated binding free energies was -14.61 kcal/mol. Ala230, Glu232, Ser235, Gly258 and Gly260 were the main amino acid residues responsible for thrombin inhibition by gallic acid, providing a mechanistic basis for further optimization. Conclusion: This study proved that gallic acid is a direct thrombin inhibitor with platelet aggregation inhibitory effect, which could provide a basis for the follow-up research and development for novel thrombin inhibitors.

The therapeutic mechanism of PuRenDan for the treatment of diabetic nephropathy: Network pharmacology and experimental verification.

ETHNOPHARMACOLOGICAL RELEVANCE: Purendan (PRD), as a Chinese medicinal formula, behaves remarkable therapeutic effects on diabetes and complications in clinical and experimental research. However, the underlying pharmacological mechanism in the treatment of diabetic nephropathy (DN) is still unclear. AIMS: To investigate the therapeutical effects of PRD on DN and to explore its pharmacological mechanisms using network pharmacology and experimental verification. MATERIALS AND METHODS: The active compounds and putative targets in PRD, and disease-related targets of DN were extracted from public databases. The key targets were identified through the protein-protein interaction (PPI) network and module analysis. The GO and KEGG enrichment analysis were performed to discover potential pharmacological mechanisms. The expression of the key targets was detected in kidney tissue in Gene Expression Omnibus (GEO) dataset. The affinity between key proteins and corresponding compounds was evaluated by molecular docking and validated by the surface plasmon resonance (SPR) assay. The indicators on major pathways and hub genes were verified by in vivo experiments. RESULTS: In network pharmacology, 137 common targets in PRD for DN treatment were screened. The key targets and main signaling pathways including AGE-RAGE and lipid pathways were identified. The statistical difference in the expression of the key targets was verified in GSE96804 database, confirming the association with DN. The docking scores obtained from molecular docking illustrated good binding force between hub proteins and active compounds. And the good component-protein affinities were validated by SPR assay. Furthermore, the results of animal experiment indicated that PRD could ameliorate the level of serum glucose and renal function in rat model. It could regulate the expression of hub targets (AKT1, MAPK3, and STAT3) and improve indicators related with oxidative stress and lipid metabolism. CONCLUSION: The key targets and major signaling pathways in the treatment of PRD on DN were identified. The mechanism might relate to regulation of oxidative stress and lipid metabolism.

Purendan alleviates non-alcoholic fatty liver disease in aged type 2 diabetic rats via regulating mTOR/S6K1/SREBP-1c signaling pathway.

Older people are more likely to develop insulin resistance and lipid metabolism disorders. Purendan (PRD) is a clinically verified traditional Chinese medicine compound, which plays an obvious role in regulating lipid metabolism disorder and improving insulin sensitivity. Our study aimed to investigate the efficacy and mechanism of PRD on aged type 2 diabetes mellitus (T2DM) complicated with non-alcoholic fatty liver disease (NAFLD) rats. Sprague-Dawley rats (13 months) were fed with high-fat diet (HFD) and injected with low-dose STZ to replicate T2DM model. PRD was treated at three concentrations with metformin as a positive control. After administration, blood and liver tissue samples were collected to measure glucose metabolism indexes such as serum glucose and insulin, as well as lipid metabolism indexes such as TC, TG, LDL, HDL and FFA. Liver fat accumulation was observed by HE staining and oil red O staining. And protein expression levels of mTOR, p-mTOR, S6K1, p-S6K1 and SREBP-1c were detected by western blot. After PRD treatment, not only the insulin sensitivity and insulin resistance were significantly improved, but also the TC, TG, LDL, FFA, AST and ALT in serum and the lipid accumulation in liver tissue were significantly decreased. Moreover, PRD significantly down-regulated the expression of p-mTOR, p-S6K1 and SREBP-1c in liver tissues. In conclusion, PRD can alleviate NAFLD in aged T2DM rats by inhibiting the mTOR /S6K1/ SREBP-1c pathway.

Hypoglycemic effects of Tibetan medicine Huidouba in STZ-induced diabetic mice and db/db mice.

Objective: Huidouba (HDB) is a Chinese folk medicine used to treat diabetes in Sichuan Province, China. Therefore, we investigated the anti-diabetic effects of HDB and its underlying mechanisms. We hypothesized that HDB treatment could enhance glucose tolerance and insulin sensitivity, and thus prevent a hyperglycemia state. Methods: To test the hypothesis, streptozotocin (STZ)-induced diabetic mice and db/db mice, widely used models of hyperglycemia and insulin-resistant diabetes, were either treated with HDB, metformin, or acarbose. Blood glucose, oral glucose tolerance test, insulin tolerance test, pancreatic histopathology and serum biochemistry were detected to assess the hypoglycemic effect of HDB. Results: HDB treatments were found to show the effect in reducing glucose levels. HDB also resulted in a significant reduction in body weight and food intake in the STZ-induced diabetic mouse model. Furthermore, it significantly improved glucose and insulin tolerance in the two diabetic mouse models. Importantly, insulin, glucagon, pancreatic polypeptide, and somatostatin immunohistochemistry revealed that HDB treatment improved the function and the location of the cells in the islets compared with the other two treatments. HDB treatment resulted in significant restoration of islet function. Our results illustrated the underlying mechanism of HDB in the progression of diabetes, and HDB can be an effective agent for the treatment of diabetes. Conclusion: The results of this study suggested that HDB can reduce blood glucose levels in STZ-induced hyperglycemic mice and db/db mice.

Huidouba Improved Podocyte Injury by Down-Regulating Nox4 Expression in Rats With Diabetic Nephropathy.

Diabetic nephropathy (DN), as the most common microvascular complication of diabetes mellitus (DM), has become one of the leading causes of end-stage renal disease (ESRD). Numerous studies have indicated that podocyte loss plays an important role in the development of DN and can even cause proteinuria in the early stage of DN. In the study, we found that Huidouba (HDB) significantly decreased the level of fasting blood glucose (FBG), the ratio of microalbumin to urine creatine (mAlb/Ucr), serum creatine (Scr), serum urea nitrogen (BUN), and malondialdehyde (MDA) in the kidney and downregulated the expression of Nox4 predominantly located in glomerular tissue while upregulating nephrin and WT1 expression in DN rats. In addition, HDB could also reduce podocyte damage and glomerular basement membrane (GBM) pathologic changes, as shown by transmission electron microscopy (TEM). In vitro study showed that HDB could inhibit high glucose (HG)-induced Reactive Oxygen Species (ROS) production and protect against podocyte apoptosis by downregulated Nox4 expression in podocytes. These results may provide a scientific basis for developing HDB as a potential folk medicine for the treatment of DN.

A Network Pharmacology Approach to Explore Mechanism of Action of Longzuan Tongbi Formula on Rheumatoid Arthritis.

Longzuan Tongbi Formula (LZTB) is an effective proved prescription in Zhuang medicine for treating active rheumatoid arthritis (RA). However, its active ingredients, underlying targets, and pharmacological mechanism are still not clear in treating RA. We have applied network pharmacology to study LZTB and found that 8 herbs in LZTB and 67 compounds in the 8 herbs are involved in the regulation of RA-related genes; we have conducted pathway analysis of overlapping genes and found that 7 herbs participate in the regulations of 24 pathways associated with RA and that 5 herbs in the 7 herbs and 25 compounds in the 5 herbs participate in the regulation of hsa05323 (rheumatoid arthritis). The results indicated that all herbs in LZTB and some compounds in those herbs participate in the treatment of RA; 25 compounds are main active ingredients and hsa05323 (rheumatoid arthritis) is the major pathway in the treatment of RA. We have also found that three pathways (inflammatory mediator regulation of TRP channels, PPAR signaling pathway, and mTOR signaling pathway) might have some effect on the treatment of RA.

[Study on extraction process of coumarin in a Mongolian drug Chagan-sorlo (Radix Glehniae)].

The present paper discusses ultrasonic extraction method aided extraction of coumarin from a Mongolian drug, Chagan-sorlo (Radix Glehniae), aiming to study out how much coumarin contained in Chagan-sorlo, and to provide the scientific basis and production guidance for extracting coumarin from Chagan-sorlo. Under different conditions the coumarin in Chagan-sorlo was extracted by ultrasonic, measured and analyzed, and then HPLC was used to carry out the measurement. Result showed that with solvent volume fraction of 70%, extraction time of 20 min, ultrasonic power of 175 W, temperature of 25 degrees C, solid-liquid ratio of 1 : 20, and 80-100 mesh extraction, the coumarin extraction reaches the highest yield.

The effect of Chinese medicine Pu-Ren-Dan on pancreatic angiogenesis in high fat diet/streptozotocin-induced diabetic rats.

OBJECTIVES: The islet vascular system is critical for ß-cell function. This study investigated the antidiabetic effect of the Chinese Pu-Ren-Dan (PRD) recipe by regulating the pancreatic angiogenic factors in T2DM rats. MATERIALS METHODS: High fat diet/streptozotocin-induced obese type-2 diabetes mellitus rats were developed and treated with PRD for 4 weeks. Then glucolipid metabolism, insulin secretion, pancreatic blood flow, ultrastructure of islet ß-cell, histological changes of islet and protein expressions of pancreatic angiogenic factors were investigated. RESULTS: PRD-reduced T2DM rats' body weight and blood glucose level resisted the lipid metabolism disturbance, and ameliorated the insulin resistance and ß-cell function. In addition, the histological and morphological studies proved that PRD could maintain the normal distribution of endocrine cell in islet and normal ultrastructure of ß cell. An increased pancreatic blood flow was observed after the PRD treatment. In the investigation of pancreatic angiogenic factors, PRD inhibited the decreased expression of VEGF and Ang-1, and reversed the reduction of VEGFR2 and Tie2 phosphorylation in T2DM rats; the Ang-2 and TGFß expression were up-regulated by PRD while PKC was activated; endostatin and angiostatin were down-regulated by PRD. CONCLUSIONS: The results suggest that increasing VEGF expression, regulating VEGF/VEGFR2 signaling, stimulating Ang-1/Tie-2 signaling pathway, and inhibiting PKC-TGFß signaling and antiangiogenic factors might be the underlying mechanism of PRD's antidiabetic effect.

[Impacts of climate warming on nine element contents in Mongolian drug Agi using ICP-AES].

Global warming has become a fact of life, and the night temperature increase higher than during the day. In the present research, to explore the effects of climate warming on element contents of plants, ICP-AES was used for the direct determination of nine kinds of element contents of reproductive branches and vegetative branches of the Mongolian drug Agi, which grew in the day, night and diurnal warming field. The results of the study show that the responses of reproductive branches and vegetative branches to day, night and diurnal warming were not significant different, but the negative response was greater than the positive response. The effects of day warming on the element contents were not significant, but night warming lower the contents of Al, Fe and Mn significantly. There was interaction between day warming and night warming.

[Study on the hemostatic effects in raw and charred Mongolian drug Agi and its mechanism].

OBJECTIVE: To observe the effects of raw and charred Agi on hemostasis and its mechanism. METHODS: The rabbit bleeding time was measured by traumatic hemorrhage test, and the clotting time was measured by tube test. The rabbit prothrombin time (PT), activated partial thormboplastia time (APTT), thrombin time (TT), fibrinogen (FIB), plasma recalcification time (PRT), euglobulin lysis time (ELT), max platelet aggregation rate (MPAR) were measured by solidification method, turbidimetry and tube test to analyze the effects of raw and charred Agi on rabbit coagulation-fibrinolysis system and platelet function. RESULTS: The medium doses and high doses of raw Agi groups, all of the groups of charred Agi decreased rabbit BT obviously (P<0.01 or P<0.05); all of the groups of raw and charred Agi declined rabbits CT (P<0.01 or P<0.05). All of the doses groups of raw and charred Agi had no apparent influences on PT (P>0.05); the high dose of raw Agi group and all of the groups of charred Agi decreased APTT apparently (P<0.01 or P<0.05) and prolonged ELT (P<0.01 or P<0.05); the high doses groups of raw and charred Agi decreased TT apparently (P<0.01 or P<0.05); the medium and high doses groups of charred Agi increased FIB obviously (P<0.01 or P<0.05); the high doses group of charred Agi showed the decreased PRT significantly (P<0.05) and increased MPAR obviously (P<0.01). CONCLUSIONS: Raw Agi can play its role in hemostasis and coagulation by affecting the intrinsic pathway of coagulation and fibrinolytic system. These effects are inhanced after processing drugs; moreover, the charred Agi could increase FIB and MPAR with promoting more in blood coagulation.

Effective compounds group of Mongolian prescriptions BAIMAI-SAN protect against peripheral neuropathy in lower limbs of rats through neuro protective effect.

ETHNOPHARMACOLOGICAL RELEVANCE: BAIMAI-SAN prescription is a famous Chinese minority complex prescription used for curing neuropathy. MATERIALS AND METHODS: The Effective Compounds Groups of BAIMAI-SAN (ECGBM) is determined by high through-put screening, and it includes picroside II, verbascose, taurine and ellagic acid and borneol. To research the potential protective effect of ECGBM on the function of peripheral neuropathy, diabetic rats with peripheral neuropathy were induced by streptozotocin and treated with ECGBM (0.1, 0.3, 0.9 mg/kg/day i.g.) for 75 days. Primary cortical neuronal cultures were subjected to high d-glucitol, and treated with ECGBM prophylactically. RESULTS: The administration resulted in reductions in speed of sciatic motor nerve conduction velocity (MNCV), sensory nerve conduction velocity (SNCV) and response speed to pain in the sciatic nerve fiber. Data from primary cortical neuronal cultures experiments indicated that neuronal survival rates were increased, and LDH release was decreased and the loss of neurite length was alleviated in ECGBM group. CONCLUSIONS: It is first report that ECGBM could protect the peripheral neuron in diabetic rat in vivo and in vitro. This activity may be associated with the neuron protective effect.

[Determination of eight metal elements in Cichorium glandulosum Boiss et Huet by microwave digestion-FAAS].

The Cichorium glandulosum Boiss et Huet is a traditional Uighur natural herbal medicine, but has not been analyzed and studied in terms of its metal elements. In the experiment, the Cichorium glandulosum Boiss et Huet powder was digested with HNO3 by microwave digestion before determination. The eight metal elements, potassium, nickel, calcium, magnesium, iron, manganese, copper and zinc, in Cichorium glandulosum Boiss et Huet were determined by FAAS. The working conditions, accuracy and precision of the method were studied. The linear correlations of standard curves are good (r = 0.999 1-0.999 9). The recovery (n = 6) is 92.25%-110.5%, and the RSD (n = 6) is 0.7%-3.88%. The results showed that there were comparatively rich metal elements, among which are comparatively high calcium (65.84 mg x g(-1)), iron (24.38 mg x g(-1)), magnesium (278.17 mg x g(-1)) and potassium (18.50 mg x g(-1)), in Cichorium glandulosum Boiss et Huet, and the contents of other elements are nickel of 0.004 38 mg x g(-1), manganese of 0.52 mg x g(-1), copper of 0.016 5 mg x g(-1) and zinc of 0.18 mg x g(-1). This provided useful data for discussing the relationship between the content of the metal elements in Cichorium glandulosum Boiss et Huet and its clinical application in cardiovascular and osteoporosis disease.

[Application and projects approved for fundamental research on integrated traditional Chinese and Western medicine in National Natural Science Foundation of China from 2000 to 2004].

From 2000 to 2004, the National Natural Science Foundation of China (NSFC) accepted 1 171 applications and funded 160 projects for fundamental research on integrated traditional Chinese and Western medicine. The success rate is 13.64%. Being supported by NSFC, a number of achievements well known in China and abroad have been made, such as acupuncture complementary anaesthesia, treatment of leukemia, viral hepatitis, cardio-cerebrovascular diseases, acute abdomen, burns and fracture with integrated traditional Chinese and Western medicine and their therapeutic mechanisms, and some new concepts and theories have been put forward, such as the theories of activating blood to resolve stagnation, simultaneous treatment of bacteria and toxin, etc. But there still exit some problems in the research of the funded projects. The research ways are mainly combination of different methods instead of integration of both traditional Chinese and Western medicine. The research results are mainly confirmation of traditional Chinese medical theories instead of exploration of their innate regularities. The relationship among disease, syndrome and symptom is not clearly explored. The principal-subordinate relationship between macro- and micro-differentiation of syndromes is not clear. Academic research is short of new ideas. Improper or biased explanation of the theories of traditional Chinese medicine still exists. On analysis of above problems, some preferable aspects of projects for fundamental research on integrated traditional Chinese and Western medicine funded by NSFC in future are suggested in this article.