Traditional Chinese medicine was guided by the idea of holistic view and dialectical treatment which was prescribed according to "Kun, Chen, Zuo, Shi". Therefore, the traditional Chinese medicine compound had the characteristics of "multiple-target, multiple-direction, multiple-layer" and had unique advantages in terms of difficult disease to treat. However, the specific mechanism of JJT in treatment of T2DM has not been clarified so far. Therefore, this study was based on network pharmacology method, with the help of corresponding bioinformatic databases and software to construct networks and analyze the targets of pathway enrichment. The result was to scientifically explore the molecular mechanism of JJT in treatment for T2DM.
JJT (Z10920027) (Tianjin Zhongxin Pharmaceutical Group Co., Ltd. Long shun Rong Pharmaceutical Factory, batch number FD87103) has been used clinically for many years and a large number of clinical studies have shown that JJT could improve the insulin resistance of T2DM patients significantly. The group of prescriptions was a traditional Chinese medicine compound preparation consisting of Coptidis Rhizoma,Hedysarum Multijugum Maxim and Lonicerae Japonicae Flos. It had the effect of clearing heat and nourishing qi and had good blood sugar and blood lipid lowering effects. It was clinically used to treat mild and moderate non-insulin dependent diabetes mellitus . The Coptidis Rhizoma of prescription had coldness, bitterness, and homeostasis, liver, gallbladder, spleen, stomach, large intestine meridian. It had the effects of clearing away heat and dampness, purging fire and detoxifying. Modern pharmacological studies have found  that the main chemical component was berberine, which could significantly improve the β-cell apoptosis. Ni Yanxia observed that the hypoglycemic mechanism of Coptidis Rhizoma was not only anti-glycemic hormone, but also related to the promotion of β-cell regeneration and functional recovery through animal experiments. Hedysarum Multijugum Maxim was slightly warm and sweet in the nature, which belonged to the lung, spleen, kidney, and liver meridians. It was one of the representative medicines for qi-enhancing medicine and had the effects of qi-enhancing yang and strengthened the body . In modern pharmacological research, Hedysarum Multijugum Maxim contained many effective chemical compounds itself and its pharmacological effects were widely used in the field of diabetes. In terms of material metabolism, it could significantly reduce the blood glucose, blood lipids and low-density lipoprotein of T2DM, and effectively improve high-density lipoprotein. Especially in terms of glucose metabolism, it also had a two-way regulation effect, which had a reducing effect on the increase of blood glucose caused by various reasons and could also counteract the decrease of blood glucose mainly caused by phenformin. Lonicerae Japonicae Flos had a long history of medicinal use and remarkable efficacy. It had been known as a good medicine for clearing heat and detoxifying since ancient times. It was mainly used to treat carbuncle, scabies, erysipelas, fever toxins fever, colds fever. In modern pharmacological research shown that it also had effect of antibacterial, antiviral, anti-inflammatory, choleretic, liver-protective, hypoglycemic and other effects.Clinical observations indicated it played a significant role in Qi and Yin deficiency and fire and prosperous for patients with mild to moderate T2DM patients .
Some literature  reported that JJT had obvious hypoglycemic, lipid-lowering, and anti-oxidant effects on T2DM Qi-yin deficiency and fire deficiency and could significantly reduce acetylcholinesterase, serum islet levels and excessive hemoglobin. Therefore, it was an ideal Chinese patent medicine for the treatment of T2DM. This study systematically analyzed the active compounds of JJT and their corresponding hypoglycemic targets. According to the compound-target network (Fig. 3)and active compounds-disease targets_(Fig. 5), it was found that there were twenty-five active compounds in JJT. There were 114 targets involved, each compound could correspond to multiple targets, and one target also corresponded to multiple components, which also reflected the characteristics of traditional Chinese medicine with multiple components and multiple targets. The study have shown that the key compounds in JJT to treat T2DM may be berberine, baicalein, berberrubine,β-carotene, stigmasterol, etc. It has been reported that berberine had obvious antioxidant, anti-inflammatory, hypoglycemic and lipid-lowering effects . It could inhibit the activity of acetylcholinesterase (AChE) and activate α7 nicotinic type in human liver cancer (HepG2) cells. Acetylcholine receptor (α7nAChR) could improve insulin resistance and reverse inflammation . It could also block mitochondrial dysfunction and AMP accumulation caused by histone deacetylase 3 (SIRT3)and block glucagon signaling and degradation PEPCK1, inhibit gluconeogenesis, promote glycolysis, thereby achieving the effect of reducing blood sugar , It also could reduce the inflammatory response, improve insulin resistance by inhibiting the binding of Toll-like receptors to lipopolysaccharides and inhibit oxidation Stress and inflammatory responses inhibit the occurrence and development of T2DM . Baicalein could reduce blood glucose by eliminating free radicals and antioxidants , lower blood lipids, inhibit α-glucosidase activity , regulate inflammatory cytokines and protect β-cell function . With the discovery of the hypoglycemic effect of berberrubine and the deepening of its mechanism research, researchers have used chemical synthesis to insert aminomethyl at the twelve position of berberrubine base to form a derivative. It’s effect may exceed berberine and insulin .β-carotene had strong anti-oxidant and immune-regulating effects , which could effectively scavenge oxygen free radicals, reduce lipid peroxide damage and effectively inhibit unsaturated fatty acid free radical chain reactions on cell membranes ,reduce insulin resistance, lower blood sugar . Stigmasterol was anti-diabetic, WARD et al  found that stigmasterol could improve the increase of free cholesterol caused by glucolipid toxicity in insulinoma cells (INS-1), which led to defects in insulin secretion, increased total insulin, and promoted stimulus protein recombination and also had been shown that played a beneficial role in the treatment of T2DM. Wang et al.  found that in vitro experiments, treating of L6 cells with different concentrations of stigmasterol had a significant effect on promoting glucose uptake. In the in vivo test, after oral administration of stigmasterol, fasting blood glucose levels and blood lipid indexes (such as triacylglycerol and cholesterol) in KK-AY mice were significantly reduced, which significantly reduced insulin resistance and oral glucose tolerance in KK-AY mice. The mechanism may be related to increase translocation and expression of glucose transporter 4 (GLUT4), suggesting that stigmasterol has potential benefits for the treatment of type 2 diabetes. The results of this study are consistent with the above report, which shows that JJT have the characteristics of multiple components acting together in the treatment of T2DM.
The PPI network shown that there were twenty-one nodes in the PPI network (Fig. 6), which represented genes related to T2DM and forty-five edges represented interaction pairs between genes, indicating that T2DM was a complex genetic diseases. Combining the component-target network (Fig. 3)_and active compounds-disease targets_(Fig. 5) and PPI network (Fig. 6) showed that RXRA,PPARG, RXRB,CYP1A2,CYP3A4,DPP4, etc. were the core targets for the treatment of T2DM. They were involved in the pathological process of T2DM and it was also the key targets of JJT in the treatment of T2DM. Among them, RXRA gene was mainly expressed in liver, kidney, skin and other tissues and was the most abundant retinoic acid X receptor in the skin [44–45]. It was not only involved in a variety of physiological processes (cell development, apoptosis, and homeostasis) and also played an important role in cholesterol balance, intestinal cholesterol absorption, bile acid synthesis. The RXRA gene agonists had hypoglycemic, insulin-sensitizing and anti-obesity effects_[46–47].Peroxisome proliferator-activated receptor gamma (PPARG) bind to form heterodimers and helped regulate homeostasis in glucose and lipid metabolism . Ying et al.  suggested that the potential functional polymorphisms of PPARG and RXRA genes may change the risk of T2DM by increasing the activity of the human ADIPO promoter. Some studies found that PPARG gene was located at 3p25, which belonged to the nuclear hormone receptor superfamily of transcription factors and played an important role in the differentiation of adipocytes and the expression of adipocyte-specific genes and the regulation of insulin sensitivity .In the state of DM, the function and expression level of certain CYP450 (CYP3A4) enzyme subtypes changed, resulting in corresponding changes in the pharmacokinetics of the substrate drug, which affected the efficacy of the drug or led to the occurrence of adverse reactions [51–52]. CYP1A2 was one of the important members of the CYP450 family. It was mainly expressed in the liver, involved in the metabolism of a variety of endogenous substrates and drugs, activated and inactivated a variety of pre-carcinogens, which had important pharmacological and toxicological significance. Hu Nan et al.  conducted a preliminary exploration on the mechanism of liver CYP1A2 changed in diabetic state at the in vitro cell level and found that abnormal changes in fatty acid concentrations may be part of the reasons that affected the function and expression change of liver CYP1A2. The study of liver CYP1A2 change provided a basis to further explore the state of diabetes. DPP4 is an enzyme in the body, that is, enzymes. Its main function is to break down proteins in the body. One of the proteins broken down by DPP4 is called GLP-1. It is a hormone secreted by intestinal cells. GLP-1 can pass through DPP4 inhibitors that stimulate insulin, inhibit glucagon, inhibit gastric emptying, and regenerate islet cells to lower blood sugar; DPP4 inhibitors that cause DPP4 inactivation and do not break down GLP-1 have become one of the main directions for the treatment of diabetes .
KEGG pathway analysis shown that a total of twelve signal pathways with P < 0.05 were screened out. Among them, the most significant pathways included Neuroactive ligand-receptor interaction, Calcium signaling pathway, cGMP-PKG signaling pathway, Serotonergic synapse, Adrenergic signaling in cardiomyocytes and PPAR signal pathway. The neuroactive ligand-receptor interaction signaling pathway is a collection of all receptor ligands on the plasma membrane that are related to intracellular and extracellular signaling pathways and is most closely related to neural function_.DM is a long-term progressive developmental disease that is mainly manifested by abnormal glucose and lipid metabolism. DM can cause coronary heart disease and diabetic cardiomyopathy. Diabetes can cause obvious myocardial cell apoptosis, which may cause heart damage caused by diabetes It plays a very important role, and the accumulation of reactive oxygen species (ROS) and oxidative stress are important factors in the occurrence of cardiomyocyte apoptosis. Since the abnormal "calcium signal" of atrial muscle cells is a key link in the regulation of atrial fibrillation, and diabetes is related to oxidative stress, the cardiac calcium channels RYR and IP3 contained in the heart are more sensitive to oxidative stress, because RYR and IP3 regulatory proteins contain A large amount of free thiol, which is the target of ROS and nitro substances, so diabetic hyperglycemia can produce oxidative stress and may affect intracellular calcium channels.The PPAR signaling pathway may play an important role in improving the fat level of T2DM patients by JJT. PPAR was a peroxisome proliferator-activated receptor, which mainly included three isoforms of α, β / δ, and γ. PPARα was mainly expressed in brown adipocytes with fast fatty acid catabolism, followed by liver, kidney, heart, and skeletal muscle cells. PPARα could regulate cholesterol and free fatty acids through multiple pathways . PPARβ was widely expressed and it played a role in fatty acid catabolism, energy metabolism and reverse cholesterol transport. PPAR-γ regulated glucose metabolism mainly by increasing the sensitivity of peripheral tissues to insulin, thereby improving insulin resistance .