Anti-hyperglycemic and anti-hyperlipidemia effects of the alkaloid-rich extract from barks of Litsea glutinosa in ob/ob mice

Detoxification and underlying mechanisms towards toxic alkaloids by Traditional Chinese Medicine processing: A comprehensive review

BACKGROUND

Alkaloids have attracted enduring interest worldwide due to their remarkable therapeutic effects, including analgesic, anti-inflammatory, and anti-tumor properties, thus offering a rich source for lead compound design and new drug discovery. However, some of these alkaloids possess intrinsic toxicity. Processing (Paozhi) is a pre-treatment step before the application of herbal medicines in traditional Chinese medicine (TCM) clinics, which has been employed for centuries to mitigate the toxicity of alkaloid-rich TCMs.

PURPOSE

To explore the toxicity phenotypes, chemical basis, mode of action, detoxification processing methods, and underlying mechanisms, we can gain crucial insights into the safe and rational use of these toxic alkaloid-rich herbs. Such insights have the great potential to offer new strategies for drug discovery and development, ultimately improving the quality of life for millions of people.

METHODS

Literatures published or early accessed until December 31, 2023, were retrieved from databases including PubMed, Web of Science, and CNKI. The following keywords, such as "toxicity", "alkaloid", "detoxification", "processing", "traditional Chinese medicine", "medicinal plant", and "plant", were used in combination or separately for screening.

RESULTS

Toxicity of alkaloids in TCM includes hepatotoxicity, nephrotoxicity, neurotoxicity, cardiotoxicity, and other forms of toxicity, primarily induced by pyrrolizidines, quinolizidines, isoquinolines, indoles, pyridines, terpenoids, and amines. Factors such as whether the toxic-alkaloid enriched part is limited or heat-sensitive, and whether toxic alkaloids are also therapeutic components, are critical for choosing appropriate detoxification processing methods. Mechanisms of alkaloid detoxification includes physical removal, chemical decomposition or transformation, as well as biological modifications.

CONCLUSION

Through this exploration, we review toxic alkaloids and the mechanisms underlying their toxicity, discuss methods to reduce toxicity, and unravel the intricate mechanisms behind detoxification. These offers insights into the quality control of herbs containing toxic alkaloids, safe and rational use of alkaloid-rich TCMs in clinics, new strategies for drug discovery and development, and ultimately helping improve the quality of life for millions of people.

Total Synthesis of the Racemate of Laurolitsine

The total synthesis of laurolitsine was achieved for the first time. This reaction was accomplished in 14 steps with a 2.3% yield (this was calculated using 3-hydroxy-4-methoxybenzaldehyde as the starting material) starting from two simple materials, 3-hydroxy-4-methoxybenzaldehyde and 2-(3-hydroxy-4-methoxyphenyl)acetic acid, and the longest linear sequence consisted of 11 steps. The key steps included an electrophilic addition reaction in which a nitro group was reduced to an amino group using lithium tetrahydroaluminum and a Pd-catalyzed direct biaryl coupling reaction. In this paper, many of the experimental steps were optimized, and an innovative postprocessing method in which 2-(3-(benzyloxy)-4-methoxyphenyl)ethanamine is salted with oxalic acid was proposed.

Two rare flavonoid glycosides from Litsea glutinosa (Lour.) C. B. Rob.: experimental and computational approaches endorse antidiabetic potentiality

BACKGROUND

Litsea glutinosa (Lour.) C. B. Rob. belongs to the Litsea genus and is categorized under the family of Lauraceae. The study aimed to investigate the phytoconstituents and pharmacological properties of methanol extract of leaves of Litsea glutinosa, focusing on antidiabetic activity via in vivo and in silico techniques.

METHODS

Extensive chromatographic and spectroscopic techniques were applied to isolate and characterize the constituents from the L. glutinosa plant species. The antidiabetic activity was studied in streptozotocin-induced diabetes mice, and the computational study of the isolated compounds was carried out by utilizing AutoDock Vina programs. In addition, the pharmacokinetic properties in terms of absorption, distribution, metabolism and excretion (ADME) and toxicological profiles of the isolated compounds were examined via in silico techniques.

RESULTS

In the present study, two flavonoid glycosides 4΄-O-methyl (2 ̋,4 ̋-di-E-p-coumaroyl) afzelin (1) and quercetin 3-O-(2 ̋,4 ̋-di-E-p-coumaroyl)-α-L-rhamnopyranoside (2) were isolated from the leaves of L. glutinosa and characterized by 1H and 13C NMR, COSY, HSQC, HMBC, and mass spectral data. Although compounds 1 and 2 have been reported twice from Machilis litseifolia and Lindera akoensis, and Machilis litseifolia and Mammea longifolia, respectively, this is the first report of this isolation from a Litsea species. Administering the methanolic extract of L. glutinosa at doses of 300 and 500 mg/kg/day to mice with diabetes induced by streptozotocin led to a significant decrease in fasting blood glucose levels (p < 0.05) starting from the 7th day of treatment. Besides, the computational study and PASS analysis endorsed the current in vivo findings that the both isolated compounds exerted higher binding affinities to human pancreatic α-amylase and aldose reductase than the conventional drugs. The in silico ADMET analysis revealed that the both isolated compounds have a favorable pharmacokinetic and safety profile suitable for human consumption.

CONCLUSION

According to the current outcomes obtained from in vivo and in silico techniques, the leaf extract of L. glutinosa could be a natural remedy for treating diabetes, and the isolated phytoconstituents could be applied against various illnesses, mainly hyperglycemia. However, more investigations are required for extensive phytochemical isolation and pharmacological activities of these phytoconstituents against broader targets with exact mechanisms of action.

Growth performance, bile acid profile, fecal microbiome and serum metabolomics of growing-finishing pigs fed diets with bile acids supplementation

The present experiment was conducted to determine the effect of bile acids (BAs) supplementation on growth performance, BAs profile, fecal microbiome, and serum metabolomics in growing-finishing pigs. A total of 60 pigs [Duroc × (Landrace × Yorkshire)] with an average body weight of 27.0 ± 1.5 kg were selected and allotted into one of 2 groups (castrated male to female ratio = 1:1), with 10 replicates per treatment and 3 pigs per replicate. The 2 treatments were the control group (control) and a porcine bile extract-supplemented group dosed at 0.5 g/kg feed (BA). After a 16-wk treatment, growth performance, BAs profiles in serum and feces, and fecal microbial composition were determined. An untargeted metabolomics approach using gas chromatography with a time-of-flight mass spectrometer was conducted to identify the metabolic pathways and associated metabolites in the serum of pigs. We found that BAs supplementation had no effect on the growth performance of the growing-finishing pig. However, it tended to increase the gain-to-feed ratio for the whole period (P = 0.07). BAs supplementation resulted in elevated serum concentrations of secondary bile acids, including hyodeoxycholic acid (HDCA), glycoursodeoxycholic acid, and tauro-hyodeoxycholic acid, as well as fecal concentration of HDCA (P < 0.05). Fecal microbiota analysis revealed no differences in alpha and beta diversity indices or the relative abundance of operational taxonomic units (OTUs) at both phylum and genus levels between groups. Metabolic pathway analysis revealed that the differential metabolites between control and BA groups are mainly involved in purine metabolism, ether lipid metabolism, glycerophospholipid metabolism, and amino sugar and nucleotide sugar metabolism, as well as primary bile acid biosynthesis. Our findings indicate that BAs supplementation tended to improve the feed efficiency, and significantly altered the BA profile in the serum and feces of growing-finished pigs, regardless of any changes in the gut microbial composition. The altered metabolic pathways could potentially play a vital role in improving the feed efficiency of growing-finished pigs with BAs supplementation.

Ethnomedicinal Uses, Phytochemistry, and Therapeutic Potentials of Litsea glutinosa (Lour.) C. B. Robinson: A Literature-Based Review

Litsea glutinosa (Lour.) C. B. Robinson, belonging to the family Lauraceae, is a multipurpose and fast-growing evergreen or deciduous tree that has been traditionally used for numerous purposes such as treatment for diarrhea, dysentery, abdominal pain, indigestion, gastroenteritis, edema, traumatic injuries, colds, arthritis, asthma, diabetes, pain relief, and poignant sexual power. This study aimed to summarize the chemical reports, folk values, and phytopharmacological activities of L. glutinosa, based on available information screened from diverse databases. An up-to-date electronic-based search was accomplished to obtain detailed information, with the help of several databases such as Google Scholar, Scopus, SpringerLink, Web of Science, ScienceDirect, ResearchGate, PubMed, ChemSpider, Elsevier, BioMed Central, and the USPTO, CIPO, INPI, Google Patents, and Espacenet, using relevant keywords. Outcomes advocate that, up to the present time, alkaloids, glycosides, and terpenoids are abundant in, and the most bioactive constituents of, this natural plant. Results demonstrated that L. glutinosa has various remarkable biological activities, including antioxidant, anti-inflammatory, anti-microbial, anticancer, antipyretic, anti-diabetic, analgesic, hepatoprotective, and wound-healing activity. One study revealed that L. glutinosa exhibited significant aphrodisiac and anti-infertility activity. Nevertheless, no clinical studies have been cited. Taken together, L. glutinosa may be one of the significant sources of bioactive constituents that could potentially lead to different effective pharmacological activities. On the other hand, future research should focus on clinical studies and several toxicity evaluations, such as sub-chronic toxicity, teratogenicity, and genotoxicity.

A high-throughput lipidomics and transcriptomic approach reveals novel compounds from sugarcane linked with promising therapeutic potential against COVID-19

Sugarcane (Saccharum ssp., Poaceae) provides enormous metabolites such as sugars, lipid, and other dietary metabolites to humans. Among them, lipids are important metabolites that perform various functions and have promising pharmacological value. However, in sugarcane, few studies are focusing on lipidomics and few lipid compounds were reported, and their pharmacological values are not explored yet. The transcriptomic and widely targeted lipidomics approach quantified 134 lipid compounds from the rind of six sugarcane genotypes. These lipid compounds include 57 fatty acids, 30 lysophosphatidylcholines, 23 glycerol esters, 21 lysophosphatidylethanolamines, 2 phosphatidylcholines, and 1 sphingolipid. Among them, 119 compounds were first time reported in sugarcane rind. Seventeen lipids compounds including 12 fatty acids, 2 glycerol lipids, LysoPC 16:0, LysoPE 16:0, and choline alfoscerate were abundantly found in the rind of sugarcane genotypes. From metabolic and transcriptomic results, we have developed a comprehensive lipid metabolic pathway and highlighted key genes that are differentially expressed in sugarcane. Several genes associated with α-linolenic acid and linoleic acid biosynthesis pathways were highly expressed in the rind of the ROC22 genotype. ROC22 has a high level of α-linolenic acid (an essential fatty acid) followed by ROC16. Moreover, we have explored pharmacological values of lipid compounds and found that the 2-linoleoylglycerol and gingerglycolipid C have strong binding interactions with 3CL^pro of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) and these compounds can be utilized against SARS-CoV-2 as therapeutic agents. The transcriptome, metabolome, and bioinformatics analysis suggests that the sugarcane cultivars have a diversity of lipid compounds having promising therapeutic potential, and exploring the lipid metabolism will help to know more compounds that have promising cosmetic and pharmacological value.

Formulating anti-diabetic nutraceutical tablets based on edible plants from Tripura, India

Nutraceuticals are food-based drugs that are used as dietary supplements to minimize chronic diseases. Diabetes is one of the most common chronic diseases all over the world. Recently, herbal nutraceuticals have taken a promising role in treating diabetes. We aimed to develop herbal nutraceutical tablets and evaluate its anti-diabetic activity using ob/ob mice. Five plant species were collected by field survey methods based on oral interviews with traditional healers of Tripura. The wet granulation method was applied to formulate the herbal nutraceutical tablet. Water- and fat-soluble vitamins were determined by reversed-phase high-performance liquid chromatography. Trace elements were analyzed by atomic absorption spectrophotometry. To evaluate the anti-diabetic activity of the herbal tablets, we determined serum hemoglobin, glycosylated serum protein, and oral glucose tolerance. The newly formulated herbal nutraceutical tablets provided the optimal energy level. It contained sufficient amounts of essential minerals, such as iron (74.6 ± 2.7 mg/g), sodium (4.4 ± 0.4 mg/g), potassium (5.3 ± 0.7 mg/g), calcium (163.1 ± 2.2 mg/g), magnesium (39.2 ± 1.7 mg/g), and phosphorus (14.6 ± 2.1 mg/g). We also found optimal quantities of water-soluble vitamins, such as vitamin C (27.2 ± 4.3 mg/g), vitamin B1 (0.6 ± 0 mg/g), vitamin B3 (0.6 ± 0.2 mg/g), vitamin B6 (1.1 ± 0.2 mg/g), vitamin B12 (0.6 ± 0.2 mcg/g), and folic acid (82.6 ± 7.6 mcg/g), as well as fat-soluble vitamins, such as vitamin A (287.4 ± 6.3 mcg/g), vitamin D3 (2.6 ± 0.6 mcg/g), and vitamin E (0.7 ± 0 ng/g). Finally, the herbal nutraceutical tablet (200 mg/kg) significantly improved the anti-hyperglycemic effect on ob/ob mice (type 2 diabetes), compared to the standard drug, metformin (200 mg/kg). The results suggest that the newly formulated herbal tablet may be recommended as an anti-diabetic nutraceutical drug.

Attenuation of obesity-induced hyperlipidemia reduces tumor growth

Accumulating evidence suggests that hyperlipidemia is associated with obesity and cancer mortality in humans. We tested the hypotheses that inhibition of microsomal triglyceride transfer protein (MTP) would attenuate obesity-induced hyperlipidemia and reduce tumor growth by treating BCR-ABL B cell tumor-bearing hyperlipidemic obese ob/ob obese mice with a MTP inhibitor. MTP inhibition in tumor-bearing mice reduced concentrations of plasma apoB100 5-fold together with a corresponding decrease in VLDL triacylglycerol (TG) and cholesterol. Inhibition of MTP decreased tumor volume by 50%. MTP inhibitor did not alter tumor cell viability in vitro, suggesting that the in vivo tumor shrinkage effect was related to altered circulating lipids. Tumor volume reduction occurred without change in the protein expression of LDLR, FASN and HMGCR in the tumor, suggesting a lack of compensatory mechanisms in response to decreased hyperlipidemia. Expression of genes encoding GLUT4 and PEPCK was increased 6- and 10-fold, respectively, but no change in the expression of genes encoding regulatory enzymes of glycolysis was observed, suggesting that the tumors were not dependent on or switching to carbohydrates for energy requirement to support their growth. No change of proliferative signaling PI3K/AKT and ERK pathways after MTP inhibition was observed in the tumors. In conclusion, MTP inhibition decreased dyslipidemia and tumor growth in obese, insulin resistant mice. Therefore, decreasing VLDL secretion could be further explored as an adjuvant therapeutic intervention together with standard care to reduce tumor growth in obese patients.

Short-term exposure to acrylamide exacerbated metabolic disorders and increased metabolic toxicity susceptibility on adult male mice with diabetes

Diabetes mellitus is a common endocrine metabolic disorder, and previous studies have shown that diabetics are more sensitive to the toxic environmental contaminants. Acrylamide (ACR) is both an industrially multipurpose compound and a common endogenous food contaminant to which people are frequently exposed and at high risk. However, the toxicity of ACR on diabetes hasn't attracted much attention. In this study, both healthy mice and diabetic mice received ACR administration orally to investigate the ACR-induced metabolic toxicity, mechanism and susceptibility to ACR toxicity in adult diabetic male mice. The results showed that ACR significantly increased FBG level and decreased bodyweight, serum lipid and liver lipid biomarkers (TC, TG, LDL-C, HDL-C) levels as well as expression of lipid and glucose metabolism-related genes in diabetic mice, indicating that ACR can exacerbate metabolic disorders of glucose and lipid in diabetic male mice. Moreover, ACR exposure significantly increased levels of MDA and COX-2), decreased GSH level and antioxidant enzyme activity (SOD, GSH-PX and CAT) by downregulating expression of Nrf2 and Keap1 in diabetic mice. Factorial analysis showed ACR had a more significant disturbance in diabetic mice compared with healthy mice. Our results indicated that ACR exposure can cause oxidative stress and inflammatory damage, which can exacerbate abnormal glucose and lipid metabolism. This work helps to elucidate the effects and underlying mechanisms of ACR-induced metabolic toxicity in adults with diabetes.

Study on the pharmacokinetics, tissue distribution and excretion of laurolitsine from Litsea glutinosa in Sprague-Dawley rats

CONTEXT

Laurolitsine is an aporphine alkaloid and exhibits potent antihyperglycemic and antihyperlipidemic effects in ob/ob mice.

OBJECTIVE

To investigate the pharmacokinetics, tissue distribution and excretion of laurolitsine.

MATERIALS AND METHODS

A LC-MS/MS method was established and validated to determine laurolitsine concentrations in the biological matrix of rats (plasma, tissue homogenate, urine and faeces). 10 Sprague-Dawley (SD) rats were used for plasma exposure study: 5 rats were injected with 2.0 mg/kg of laurolitsine via the tail vein, and the other 5 rats were administered laurolitsine (10.0 mg/kg) by gavage. 25 SD rats used for tissue distribution study and 5 SD rats for urine and faeces excretion study: rats administered laurolitsine (10.0 mg/kg) by gavage. After administered, serial blood, tissue, urine and faeces were collected. Analytical quantification was performed by a previous LC-MS/MS method. The pharmacokinetics, bioavailability, tissue distribution and excretion of laurolitsine were described.

RESULTS

The pharmacokinetic parameters of oral and intravenous administration with T_max were 0.47 and 0.083 h, t_1/2 were 3.73 and 1.67 h, respectively. Oral bioavailability was as low as 18.17%. Laurolitsine was found at a high concentration in the gastrointestinal tract, liver, lungs and kidneys (26 015.33, 905.12, 442.32 and 214.99 ng/g at 0.5 h, respectively) and low excretion to parent laurolitsine in urine and faeces (0.03 and 1.20% in 36 h, respectively).

CONCLUSIONS

This study established a simple, rapid and accurate LC-MS/MS method to determine laurolitsine in different rat samples and successful application in a pharmacokinetic study.

Antioxidant compounds from Annona crassiflora fruit peel reduce lipid levels and oxidative damage and maintain the glutathione defense in hepatic tissue of Triton WR-1339-induced hyperlipidemic mice

Dyslipidemia is a risk factor for the pathogenesis of several diseases, such as obesity, hypertension, atherosclerosis and cardiovascular diseases. In addition to interfering with serum concentrations of cholesterol and triglycerides, hyperlipidemia is involved in oxidative stress increase and reduction of the endogenous antioxidant defenses. The fruit peel of Annona crassiflora crude extract (CEAc) and its polyphenols-rich fraction (PFAc) were investigated against hypertriglyceridemia, hypercholesterolemia and hepatic oxidative stress in Triton WR-1339-induced hyperlipidemic mice. Lipid parameters in serum, feces and liver, as well as hepatic oxidative status, and enzymatic and non-enzymatic antioxidant defense systems were analyzed. Pre-treatment with CEAc for 12 days decreased hepatic triglycerides and total cholesterol, and similar to PFAc, increased the high-density lipoprotein level. There were reductions in lipid peroxidation and protein carbonylation, as well as restoration of the glutathione defense system and total thiol content in the liver of the hyperlipidemic mice treated with PFAc. The fruit peel of A. crassiflora, a promising natural source of bioactive molecules, showed a potential lipid-lowering action and hepatoprotective activities triggered by reduction of oxidative damage and maintenance of the enzymatic and non-enzymatic antioxidant systems impaired by the hyperlipidemic state.

Natural Alkaloids and Diabetes Mellitus: A Review

BACKGROUND

The use of herbal therapies for treatment and management of diabetes mellitus and complications associated with this chronic condition is increasing. Plants contain a bounty of phytochemicals that have been proven to be protective by reducing the risk of various ailments and diseases, including alkaloids. Moreover, alkaloids are known to be among the oldest natural products used by humans for highlighting drugs that play crucial roles as therapeutic agents. The reason for this expanding interest and uses of alkaloids as a part of plant natural compounds-based treatments is that a significant proportion of diabetic patients do not respond very well to conventional therapeutic medication. Furthermore, other explanations to this fact are the cost of medication, side-effects, accessibility, and availability of health facilities and drugs and the inefficiency of these medicines in certain cases.

OBJECTIVE

In this study we aimed to review the literature on the valuable effects of herbs and plants and their isolated alkaloids compounds as medication for management of diabetes, a prevalent risk factor for several other disorders and illnesses.

METHODS

In the current review, PubMed, ScienceDirect, Springer and google scholar databases were used and the criterion for inclusion was based on the following keywords and phrases: diabetes, hyperglycemia, complications of diabetes, alkaloids, antidiabetic alkaloids, hypoglycemic alkaloids, alkaloids and complications of diabetes mellitus, mechanisms of action and alkaloids.

RESULTS

In the current review, we demonstrate that alkaloids in the form of extracts and isolated molecules obtained from a large variety of species demonstrated their efficiency for improving raises in blood glucose either in animal models via experimental studies or in human subjects via clinical trials. Medicinal species as chillies (Capsicum annuum), turmeric (Curcuma longa), barberry (Berberis vulgaris) and cress (Lepidium sativum) are among the most common and therapeutic plants used for controlling diabetes that were the subject of several experimental and clinical investigations. Whereas, isolated alkaloids such as berberine, capsaicin and trigonelline have received more interest in this field. Interestingly, the therapeutic impact of alkaloids against blood glucose pathogenesis is mediated through a variety of signaling cascades and pathways, via inhibiting or stimulating diversity of systems such as inhibition of α-glucosidase enzyme, blockade of PTP- 1B, deactivation of DPP-IV, increasing insulin sensitivity and modulating the oxidative stress.

CONCLUSION

Based on the findings of the present review, alkaloids could be used as preventive and curative agents in the case of endocrine disorders, particularly diabetes and could play a promoting function for the discovery of new antidiabetic agents.

Anti-diabetic potential of plant alkaloids: Revisiting current findings and future perspectives

Diabetes mellitus (DM) is a chronic metabolic disease which causes millions of death all over the world each year, and its incidence is on increase. The most prevalent form, type 2 DM, is characterized by insulin resistance and β-cell dysfunction, whereas type 1 DM is due to insulin deficiency as a result of β-cell destruction. Various classes of synthetic drugs have been developed to regulate glucose homeostasis and combat the development of late-diabetic complications. However, several of these chemical agents are either sub-optimal in their effect and/or may have side effects. Biologically, alkaloids unveiled a wide range of therapeutic effects including anti-diabetic properties. The chemical backbones of these compounds have the potential to interact with a wide range of proteins involved in glucose homeostasis, and thus they have received increasing attention as reliable candidates for drug development. This review sets out to investigate the anti-diabetic potential of plant alkaloids (PAs), and therefore, scientific databases were comprehensively screened to highlight the biological activity of 78 PAs with a considerable anti-diabetic profile. There are not enough clinical data available for these phytochemicals to follow their fingerprint in human, but current studies generally recommending PAs as potent α-glucosidase inhibitors. Except for some classes of monoterpene alkaloids, other compounds showed similar features as well as the presently available anti-diabetic drugs such as amino sugars and other relevant drugs. Moreover, the evidence suggests that PAs have the potential to be used as alternative additives for the treatment of DM, however, further in vitro and in vivo studies are needed to validate these findings.

Scutellariae Radix and Coptidis Rhizoma Improve Glucose and Lipid Metabolism in T2DM Rats via Regulation of the Metabolic Profiling and MAPK/PI3K/Akt Signaling Pathway

Aim Scutellariae Radix (SR) and Coptidis Rhizoma (CR) have often been combined to cure type 2 diabetes mellitus (T2DM) in the clinical practice for over thousands of years, but their compatibility mechanism is not clear. Mitogen-activated protein kinase (MAPK) signaling pathway has been suggested to play a critical role during the process of inflammation, insulin resistance, and T2DM. This study was designed to investigate their compatibility effects on T2DM rats and explore the underlying mechanisms by analyzing the metabolic profiling and MAPK/PI3K/Akt signaling pathway. Methods The compatibility effects of SR and CR were evaluated with T2DM rats induced by a high-fat diet (HFD) along with a low dose of streptozocin (STZ). Ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) was performed to discover potential biomarkers. The levels of pro-inflammatory cytokines; biochemical indexes in serum, and the activities of key enzymes related to glycometabolism in liver were assessed by ELISA kits. qPCR was applied to examine mRNA levels of key targets in MAPK and insulin signaling pathways. Protein expressions of p65; p-p65; phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K); phosphorylated-PI3K (p-PI3K); protein kinase B (Akt); phosphorylated Akt (p-Akt) and glucose transporter 2 (Glut2) in liver were investigated by Western blot analysis. Results Remarkably, hyperglycaemia, dyslipidemia, inflammation, and insulin resistance in T2DM were ameliorated after oral administration of SR and CR, particularly their combined extracts. The effects of SR, CR, low dose of combined extracts (LSC) and high dose of combined extracts (HSC) on pro-inflammatory cytokine transcription in T2DM rats showed that the MAPK pathway might account for the phenomenon with down-regulation of MAPK (P38 mitogen-activated protein kinases (P38), extracellular regulated protein kinases (ERK), and c-Jun N-terminal kinase (JNK)) mRNA, and protein reduction in p-P65. While mRNA levels of key targets such as insulin receptor substrate 1 (IRS1), PI3K, Akt2, and Glut2 in the insulin signaling pathway were notably up-modulated, phosphorylations of PI3K, Akt, and expression of Glut2 were markedly enhanced. Moreover, the increased activities of phosphoenolpyruvate carboxykinase (PEPCK), fructose-1,6-bisphosphatase (FBPase), glucose 6-phosphatase (G6Pase), and glycogen phosphorylase (GP) were highly reduced and the decreased activities of glucokinase (GK), phosphofructokinase (PFK), pyruvate kinase (PK), and glycogen synthase (GS) in liver were notably increased after treatment. Further investigation indicated that the metabolic profiles of plasma and urine were clearly improved in T2DM rats. Fourteen potential biomarkers (nine in plasma and five in urine) were identified. After intervention, these biomarkers returned to normal level to some extent. Conclusion The results showed that SR, CR, and combined extract groups were normalized. The effects of combined extracts were more remarkable than single herb treatment. Additionally, this study also showed that the metabonomics method is a promising tool to unravel how traditional Chinese medicines work.