1.Mechanism of Tangbikang Dry Paste in Prevention and Treatment of Type 2 Diabetic Peripheral Neuropathy Based on GLO-1/AGE/RAGE Pathway
Lijia WU ; Chengfei ZHANG ; Xiaolei JIA ; Lingling QIN ; Haiyan WANG ; Yukun HUANG ; You WANG ; Xincui BAO ; Jing YANG ; Cuiyan LYU ; Tonghua LIU
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(11):60-69
ObjectiveTo investigate the mechanism of Tangbikang dry paste in the prevention and treatment of type 2 diabetic peripheral neuropathy (DPN) based on the glyoxalase-1 (GLO-1)/advanced glycation end products (AGE)/receptor for advanced glycation end products (RAGE) pathway. MethodsA total of 56 Sprague-Dawley rats were randomly divided, with eight assigned to the normal group. The remaining 48 rats were fed a high-fat diet combined with intraperitoneal injection of streptozotocin (STZ) to induce a type 2 diabetes mellitus (T2DM) model. Based on blood glucose levels, the rats were randomly assigned to the model group, Tanglin group (13.5 mg·kg-1), metformin group (135 mg·kg-1), and Tangbikang dry paste low-, medium-, and high-dose groups (3, 6, 12 g·kg-1). Successful modeling of DPN was confirmed by a decrease in mechanical pain threshold in the model group at week 4. Fasting blood glucose, body weight, and mechanical pain threshold were measured every 4 weeks. After 16 weeks of intervention, the pathological morphology of the sciatic nerve was observed using hematoxylin-eosin (HE) staining. The expression of RAGE, AGE, protein kinase C (PKC), and collagen (COL) in the sciatic nerve was assessed by immunohistochemistry. The mRNA expression of RAGE, PKC, Toll-like receptor (TLR), COL, and GLO-1 was detected using real-time quantitative PCR (Real-time PCR). Serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine (CREA), urea (UREA), interleukin-6 (IL-6), and tumor necrosis factor (TNF)-α were measured by enzyme-linked immunosorbent assay (ELISA). ResultsCompared with the normal group, the model group showed significantly increased fasting blood glucose (P<0.01), decreased body weight and mechanical pain threshold (P<0.01), and elevated serum AST, ALT, CREA, UREA, IL-6, and TNF-α levels (P<0.01). The expression of RAGE, AGE, and PKC in the sciatic nerve was significantly increased (P<0.01), while COL expression was decreased (P<0.01). The mRNA expression of TLR, RAGE, and PKC was upregulated (P<0.01), whereas COL and GLO-1 mRNA levels were downregulated (P<0.01). Histological examination showed irregular nerve morphology, axonal alterations, and myelin degeneration. Compared with the model group, fasting blood glucose levels in the Tangbikang dry paste high-dose group at all time points and in the medium-dose group at weeks 4 and 16 were significantly reduced (P<0.05, P<0.01). No significant changes in body weight were observed across all Tangbikang dose groups. The mechanical pain threshold was elevated at different time points after administration in all Tangbikang groups (P<0.05, P<0.01). Serum IL-6 and TNF-α levels were decreased in all dose groups (P<0.05, P<0.01). The expression of RAGE, AGE, and PKC in the sciatic nerve was reduced (P<0.01), while COL expression was increased (P<0.01). The mRNA expression of TLR, RAGE, and PKC was downregulated (P<0.01), whereas GLO-1 mRNA expression was upregulated (P<0.05, P<0.01). Additionally, COL mRNA expression was significantly increased in the low- and high-dose groups (P<0.01). Pathological changes in the sciatic nerve were milder in all Tangbikang groups compared to the model group. ConclusionTangbikang dry paste significantly improves DPN, and its mechanism may be associated with the regulation of the GLO-1/AGE/RAGE signaling pathway.
2.Mechanism of Tangbikang Dry Paste in Prevention and Treatment of Type 2 Diabetic Peripheral Neuropathy Based on GLO-1/AGE/RAGE Pathway
Lijia WU ; Chengfei ZHANG ; Xiaolei JIA ; Lingling QIN ; Haiyan WANG ; Yukun HUANG ; You WANG ; Xincui BAO ; Jing YANG ; Cuiyan LYU ; Tonghua LIU
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(11):60-69
ObjectiveTo investigate the mechanism of Tangbikang dry paste in the prevention and treatment of type 2 diabetic peripheral neuropathy (DPN) based on the glyoxalase-1 (GLO-1)/advanced glycation end products (AGE)/receptor for advanced glycation end products (RAGE) pathway. MethodsA total of 56 Sprague-Dawley rats were randomly divided, with eight assigned to the normal group. The remaining 48 rats were fed a high-fat diet combined with intraperitoneal injection of streptozotocin (STZ) to induce a type 2 diabetes mellitus (T2DM) model. Based on blood glucose levels, the rats were randomly assigned to the model group, Tanglin group (13.5 mg·kg-1), metformin group (135 mg·kg-1), and Tangbikang dry paste low-, medium-, and high-dose groups (3, 6, 12 g·kg-1). Successful modeling of DPN was confirmed by a decrease in mechanical pain threshold in the model group at week 4. Fasting blood glucose, body weight, and mechanical pain threshold were measured every 4 weeks. After 16 weeks of intervention, the pathological morphology of the sciatic nerve was observed using hematoxylin-eosin (HE) staining. The expression of RAGE, AGE, protein kinase C (PKC), and collagen (COL) in the sciatic nerve was assessed by immunohistochemistry. The mRNA expression of RAGE, PKC, Toll-like receptor (TLR), COL, and GLO-1 was detected using real-time quantitative PCR (Real-time PCR). Serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine (CREA), urea (UREA), interleukin-6 (IL-6), and tumor necrosis factor (TNF)-α were measured by enzyme-linked immunosorbent assay (ELISA). ResultsCompared with the normal group, the model group showed significantly increased fasting blood glucose (P<0.01), decreased body weight and mechanical pain threshold (P<0.01), and elevated serum AST, ALT, CREA, UREA, IL-6, and TNF-α levels (P<0.01). The expression of RAGE, AGE, and PKC in the sciatic nerve was significantly increased (P<0.01), while COL expression was decreased (P<0.01). The mRNA expression of TLR, RAGE, and PKC was upregulated (P<0.01), whereas COL and GLO-1 mRNA levels were downregulated (P<0.01). Histological examination showed irregular nerve morphology, axonal alterations, and myelin degeneration. Compared with the model group, fasting blood glucose levels in the Tangbikang dry paste high-dose group at all time points and in the medium-dose group at weeks 4 and 16 were significantly reduced (P<0.05, P<0.01). No significant changes in body weight were observed across all Tangbikang dose groups. The mechanical pain threshold was elevated at different time points after administration in all Tangbikang groups (P<0.05, P<0.01). Serum IL-6 and TNF-α levels were decreased in all dose groups (P<0.05, P<0.01). The expression of RAGE, AGE, and PKC in the sciatic nerve was reduced (P<0.01), while COL expression was increased (P<0.01). The mRNA expression of TLR, RAGE, and PKC was downregulated (P<0.01), whereas GLO-1 mRNA expression was upregulated (P<0.05, P<0.01). Additionally, COL mRNA expression was significantly increased in the low- and high-dose groups (P<0.01). Pathological changes in the sciatic nerve were milder in all Tangbikang groups compared to the model group. ConclusionTangbikang dry paste significantly improves DPN, and its mechanism may be associated with the regulation of the GLO-1/AGE/RAGE signaling pathway.
3.Research Progress on Traditional Chinese Medicine Interventions Targeting NF-κB Signaling Pathway to Improve Diabetic Nephropathy
Jiangfan GUO ; Xiaomeng WANG ; Qiu'e ZHANG ; Xiaochen LI ; Tonghua LIU ; Lili WU ; Lingling QIN ; Qingsong LI
Chinese Journal of Experimental Traditional Medical Formulae 2024;30(20):241-251
Diabetic nephropathy (DN) is a chronic microvascular complication in diabetic patients and the main cause of end-stage renal disease (ESRD). Studies have shown that nuclear factor kappa-B (NF-κB) signaling pathway is involved in the pathological process of DN by activating pathological mechanisms such as inflammation, oxidative stress, fibrosis, apoptosis, autophagy, and pyroptosis. Therefore, blocking the transduction of NF-κB signaling pathway can help prevent and treat DN. Currently, western medical treatment involves strategies such as lowering blood sugar, blood pressure, and lipids, as well as using endothelin receptor antagonists, mineralocorticoid receptor antagonists, aldosterone synthase inhibitors, and other drugs, but they still cannot block the pathological process of DN. Traditional Chinese medicine (TCM) offers a simpler and more cost-effective approach that addresses both the symptoms and underlying causes of DN. Recent research has shown promising results in managing DN with TCM, and NF-κB, as a key factor, plays an important role in the prevention and treatment of DN. This article summarized the research results of TCM based on the NF-κB signaling pathway for the treatment of DN in the past five years. It described a variety of TCM extracts, such as polysaccharides, terpenes, phenols, flavonoids, saponins, and alkaloids, as well as TCM compound prescriptions such as Huaiqihuang granules, Astragalus mongholicus Bunge and Panax notoginseng formula, and Danzhi Jiangtang capsules, which regulated the NF-κB signaling pathway and its upstream and downstream factors to block the pathological process of DN. This inhibition aims to prevent renal pathological damage caused by DN and slow down the deterioration of renal function. The article aims to provide new ideas and references for the research and development of drugs for the prevention and treatment of DN.
4.Effect of South African Herb Hoodia gordonii on Liver Glucolipid Metabolism and PI3K/Akt/FoxO1 Signalling Pathway in db/db Mice
Chengfei ZHANG ; Qiue ZHANG ; Linging QIN ; Wei LIU ; Guangyuan XU ; Xuesheng MA ; Lili WU ; Tonghua LIU
Chinese Journal of Experimental Traditional Medical Formulae 2024;30(5):57-64
ObjectiveTo observe the effects of the South African herb Hoodia gordonii (HG) on glucolipid metabolism in diabetic db/db mice and explore the possible mechanisms of HG on the liver of db/db mice based on the phosphoinositide-3 kinase (PI3K)/protein kinase B (Akt)/factor forkhead protein O1 (FoxO1) signaling pathway. MethodA total of 30 db/db mice were randomly divided into five groups according to fasting blood glucose: model group, metformin group (0.195 g·kg-1), and low dose (0.39 g·kg-1), medium dose (0.78 g·kg-1), and high dose (1.56 g·kg-1) HG groups, with six m/m mice in each group, and another six m/m mice were set as normal group. The mice in the normal and model groups were given saline of 9 mL·kg-1 by gavage. Body weight, water intake, and fasting blood glucose of the mice in each group were measured weekly. After six weeks of continuous administration, serum insulin (FINS), low-density lipoprotein cholesterol (LDL), total cholesterol (TC), triglyceride (TG), alanine aminotransferase (ALT), aspartate aminotransferase (AST), urea, and creatinine (CREA) were measured, and liver sections were embedded and stained with hematoxylin-eosin (HE), periodic acid-Schiff (PAS), and oil red O. Protein expression of PI3K p85, p-Akt, and p-FoxO1 in liver was detected by immunohistochemistry. The mRNA expression of PI3K, Akt, and FoxO1 in liver tissue was detected by real-time polymerase chain reaction (Real-time PCR). ResultAfter six weeks of administration intervention, it was found that fasting blood glucose was significantly downregulated in mice in the three HG groups (P<0.05). The level of islet resistance index was significantly reduced in both the low and medium dose HG groups (P<0.05). The expression levels of TC, TG, and LDL were reduced in all HG groups (P<0.05, P<0.01). Pathologically, HG could alleviate hepatocyte steatosis, reduce the volume and content of lipid droplets in liver, and increase the distribution of glycogen granules in liver to some extent in mice. Immunohistochemical assays revealed that PI3K p85 protein expression was significantly increased in the low, medium, and high dose HG groups compared with the model group (P<0.01). p-Akt protein expression was significantly increased in the medium and high dose HG groups (P<0.05, P<0.01). p-FoxO1 protein expression was significantly increased in the low, medium, and high dose HG groups (P<0.05, P<0.01). Compared with the model group, PI3K mRNA was increased in low dose, medium dose, and high dose HG groups (P<0.05), and Akt mRNA was increased in high dose HG group (P<0.05). FoxO1 mRNA was decreased in low dose, medium dose, and high dose HG groups (P<0.05). ConclusionHG can ameliorate the disorder of glucolipid metabolism in db/db mice, which may be related to its activation of the hepatic PI3K/Akt/FoxO1 signaling pathway.
5.Inhibition of Oxidative Stress of Sciatic Nerve in Diabetic Rats by Tangbikang Granules Regulating AMPK/PGC-1α/SIRT3 Signaling Pathway
Gang LIU ; Yaqi ZHANG ; Lingling QIN ; Chengfei ZHANG ; Qiue ZHANG ; Huizhong BAI ; Yi ZHAO ; Tonghua LIU ; Xiaohong MU
Chinese Journal of Experimental Traditional Medical Formulae 2024;30(6):75-82
ObjectiveTo investigate the effect of Tangbikang granules on oxidative stress of sciatic nerve in diabetic rats by regulating adenylate activated protein kinase/peroxisome proliferator-activated receptor γ coactivator-1α/mitochondrial Sirtuins 3 (AMPK/PGC-1α/SIRT3) signaling pathway. MethodThe spontaneous obesity type 2 diabetes model was established using ZDF rats. After modeling, they were randomly divided into high, medium, and low dose Tangbikang granule groups (2.5, 1.25, 0.625 g·kg-1·d-1) and lipoic acid group (0.026 8 g·kg-1·d-1), and the normal group was set up. The rats were administered continuously for 12 weeks after modeling. The blood glucose of rats was detected before intervention and at 4, 8, 12 weeks after intervention. At the 12th week, motor nerve conduction velocity (MNCV), sensory nerve conduction velocity (SNCV), nerve blood flow velocity, mechanical pain threshold, and thermal pain threshold were detected. The sciatic nerve was taken for hematoxylin-eosin (HE) staining to observe the tissue morphology. The ultrastructure of the sciatic nerve was observed by transmission electron microscope. The expression levels of superoxide dismutase (SOD), malondialdehyde (MDA), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) in sciatic nerve were determined by enzyme-related immunosorbent assay (ELISA). The mRNA expressions of AMPKα, AMPKβ, PGC-1α, and SIRT3 in sciatic nerve were determined by real-time polymerase chain reaction (Real-time PCR). ResultCompared with the normal group, fasting blood glucose in the model group was increased at each time point (P<0.01). The mechanical pain threshold was decreased (P<0.05), and the incubation time of the hot plate was extended (P<0.01). MNCV, SNCV, and nerve blood flow velocity decreased (P<0.05). The expression level of SOD was decreased (P<0.01). The expression levels of MDA, IL-1β, and TNF-α were increased (P<0.01). The mRNA expression levels of AMPKα, AMPKβ, PGC-1α, and SIRT3 were decreased (P<0.01). The structure of sciatic nerve fibers in the model group was loose, and the arrangement was disordered. The demyelination change was obvious. Compared with the model group, the fasting blood glucose of rats in the high dose Tangbikang granule group was decreased after the intervention of eight weeks and 12 weeks (P<0.01). The mechanical pain threshold increased (P<0.05). The incubation time of the hot plate was shortened (P<0.01). MNCV, SNCV, and Flux increased (P<0.05). The expression level of SOD was increased (P<0.01). The expression levels of MDA, IL-1β, and TNF-α were decreased (P<0.01). The mRNA expression levels of AMPKα, AMPKβ, PGC-1α, and SIRT3 were increased (P<0.01). The sciatic nerve fibers in the high-dose Tangbikang granule group were tighter and more neatly arranged, with only a few demyelinating changes. The high, medium, and low dose Tangbikang granule groups showed a significant dose-effect trend. ConclusionTangbikang granules may improve sciatic nerve function in diabetic rats by regulating AMPK/PGC-1α/SIRT3 signaling pathway partly to inhibit oxidative stress.
6.Effect of Tangbikang Granules on PI3K Pathway in Type 2 Diabetic Mellitus Rats with Non-alcoholic Fatty Liver Disease
Yaqi ZHANG ; Lingling QIN ; Chengfei ZHANG ; Qiue ZHANG ; Huizhong BAI ; Gang LIU ; Xinwei ZUO ; Yi ZHAO ; Tonghua LIU ; Xiaohong MU
Chinese Journal of Experimental Traditional Medical Formulae 2023;29(9):71-80
ObjectiveThis study aims to investigate the therapeutic effect of Tangbikang granules(TBK) on type 2 diabetes mellitus (T2DM) complicated with non-alcoholic fatty liver disease (NAFLD) and to elucidate the underlying mechanism. MethodT2DM and NAFLD were induced in ZDF rats, which were then respectively treated (ig) with low-dose (0.625 g·kg-1), medium-dose (1.25 g·kg-1), and high-dose (2.5 g·kg-1) TBK for 12 weeks. Fasting blood glucose (FBG) and body mass were recorded every 4 weeks during the treatment. One week before sampling, the feed intake of rats was detected, and after 12 h night fasting, oral glucose tolerance test (OGTT) was performed. The area under the curve (AUC) was used to evaluate glucose tolerance, and the homeostatic model assessment for insulin resistance (HOMA-IR) was calculated. Blood in abdominal aorta and liver were collected for determination of blood glucose and lipid metabolism indexes: Fasting serum insulin (FINS), serum total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), and nonesterified fatty acids (NEFA). The liver was weighed to calculate the liver index, and the liver tissue morphology was observed and analyzed based on hematoxylin-eosin (HE) staining and periodic acid-Schiff (PAS) staining. The protein levels of insulin receptor substrate (IRS), phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt) and phosphorylated IRS and Akt were detected by Western blotting. All data were analyzed by SPSS 20.0. ResultThe feed intake of the model group was higher than that in the normal group (P<0.01), and the feed intake the administration groups was lower than that in the model group (P<0.05, P<0.01). At the 8th and 12th week, the body mass in the model group was lower than that in the normal group (P<0.01). Compared with the model group, TBK reduced FBG in a concentration-dependent manner. The blood glucose level in OGTT and AUC in the model group were higher/larger than those in the normal group (P<0.01). The blood glucose value in OGTT was decreased in TBK groups and the metformin group compared with that in the model group, and AUC in the administration groups was significantly different from that in the model group (P<0.01). The serum level of FINS and HOMA-IR in the model group were higher than those in the normal group (P<0.01), and they were lower in the TBK groups than in the model group (P<0.01). Serum levels of TG, TC, HDL-C, NEFA (P<0.05, P<0.01), and LDL-C were higher in the model group than in the normal group. Serum levels of TG, TC, LDL-C, and NEFA in the TBK groups were lower than those in the model group, and the levels of TG, LDL-C, and NEFA in TBK groups were concentration-dependent (lowest levels in high-dose TBK group). Compared with the model group, high-dose TBK significantly increased the level of HDL-C (P<0.05). Liver index of the model group was higher than that in the normal group (P<0.01). The liver index of the administration groups showed a decreasing trend with no significant difference from that in the model group. As for the HE staining result of liver, the model group had unclear structure of liver lobule, enlarged cells of different sizes, and obvious steatosis of hepatocytes. TBK of all doses alleviated liver injury, particularly the high dose. For the PAS staining, compared with the normal group, the model group demonstrated significant fat vacuoles and significant reduction in purplish red glycogen granules in the cytoplasm. The staining results of high- and medium-dose groups of TBK were more similar to the normal group. Western blot was used to detect the protein expression of liver tissue. The expression of PI3K protein, p-IRS1/IRS1, and p-Akt/Akt in the model group were lower than those in the normal group (P<0.01), and they were higher in the high-dose TBK group than in the model group (P<0.01). ConclusionTBK exerts therapeutic effect on T2DM combined with NAFLD in ZDF rats by activating the typical PI3K signaling pathway.
7.Molecular Mechanism of Tangbikang Granules Against Diabetic Peripheral Neuropathy: Based on Network Pharmacology and Experimental Verification
Yaqi ZHANG ; Lingling QIN ; Huizhong BAI ; Chengfei ZHANG ; Qiue ZHANG ; Xinwei ZUO ; Shengyuan JIANG ; Yi ZHAO ; Tonghua LIU ; Xiaohong MU
Chinese Journal of Experimental Traditional Medical Formulae 2023;29(9):81-90
ObjectiveTo explore the mechanism of Tangbikang granules (TBK) against diabetic peripheral neuropathy (DPN) based on network pharmacology and in-vivo experiment. MethodThe active components in medicinals of TBK and their target genes were searched from Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP). The active components of the medicinals which are not included in TCMSP were searched from previous research. After the analysis of drug-likeness by SwissADME, the target genes of them were predicted with SwissTargetPrediction. DPN-related target genes were retrieved from GeneCards. The common targets of the disease and the prescription were the hub genes of TBK against DPN, which were uploaded to Metascape for Gene Ontology (GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. High-sugar and high-fat diet and low-dose streptozotocin (STZ, ip) were employed to induce diabetes in rats, and then the model rats were respectively treated with low-dose (0.625 g·kg-1), medium-dose (1.25 g·kg-1), and high-dose (2.5 g·kg-1) TBK for 12 weeks. Sensory nerve conduction velocity (SNCV) was evaluated. After hematoxylin and eosin (HE) staining, the sciatic nerve was observed under light microscope to examine the nerve damage. Real-time PCR was performed to detect the gene expression of adenosine monophosphate-activated protein kinase (AMPK) pathway-related targets in rat sciatic nerve, and Western blot to measure the protein expression of AMPK and phosphorylated (p)-AMPK in rat sciatic nerve. ResultThe main active components of TBK, such as quercetin, kaempferol, β-sitosterol, leech pteridine A, stigmasterol, and baicalein were screened out, mainly acting on interleukin-6 (IL-6), tumor necrosis factor (TNF), protein kinase B (Akt), JUN, and HSP90AA1 and signaling pathways such as AMPK, nuclear factor-κB (NF-κB), and Janus kinase/signal transducer and activator of transcription (JAK/STAT). Molecular docking results showed that β-sitosterol and stigmasterol had high binding affinity with IL-6, TNF, JUN, and HSP90AA1. As for the animal experiment, compared with the normal group, model group had low SNCV of sciatic nerve (P<0.01), disordered and loose myelinated nerve fibers with axonotmesis and demyelinization, low mRNA expression of AMPKα, AMPKβ, peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), Sirtuin 3 (SirT3), mitochondrial transcription factor A (TFAM), and low p-AMPK/AMPK ratio in sciatic nerve (P<0.05, P<0.01). Compared with the model group, TBK of the three doses raised the SNCV (P<0.01), restored nerve morphology and nerve compactness, and increased the mRNA expression of AMPKα, AMPKβ, PGC-1α, SirT3, and TFAM (P<0.05, P<0.01). The ratio of p-AMPK/AMPK in the high-dose and medium-dose TBK groups was higher than that in the model group (P<0.01), while the protein expression in the low-dose TBK group was insignificantly different from that in the model group. ConclusionTBK exerts therapeutic effect on DPN through multiple pathways and targets. The mechanism is that it activates and regulates AMPK/PGC-1α/SirT3 signaling, which lays a basis for further study of TBK in the treatment of DPN.
8.Tangbikang Granules Modulates AMPK/NF-κB Pathway to Alleviate Sciatic Nerve Inflammation in Diabetic Rats
Huizhong BAI ; Lingling QIN ; Yaqi ZHANG ; Chengfei ZHANG ; Qiue ZHANG ; Xinwei ZUO ; Gang LIU ; Yu ZHAO ; Yi ZHAO ; Tonghua LIU ; Xiaohong MU
Chinese Journal of Experimental Traditional Medical Formulae 2023;29(9):91-98
ObjectiveTo explore the effect of Tangbikang granules (TBK) on sciatic nerve inflammation in diabetic rats through modulation of adenosine monophosphate-activated protein kinase (AMPK)/nuclear factor (NF)-κB pathway. MethodSD rats were fed with high-fat and high-sugar diet for 8 weeks and then treated with streptozotocin (STZ, ip) at 35 mg·kg-1 for modeling. Then the rats were randomized into diabetes group, low-dose (0.625 g·kg-1), medium-dose (1.25 g·kg-1), and high-dose (2.5 g·kg-1) TBK groups, and lipoic acid group (0.026 8 g·kg-1) according to body weight and blood glucose level, and a normal group was designed. After modeling, administration began and lasted 12 weeks. The body mass, blood glucose level, and thermal withdrawal latency (TWL) of the rats were detected before treatment and at the 4th, 8th, and 12th week of administration. At the 12th week, the sciatic nerve was collected for hematoxylin-eosin (HE) and Luxol fast blue (LFB) staining, and the structural changes of sciatic nerve were observed under scanning electron microscope. The levels of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in sciatic nerve were measured by enzyme-linked immunosorbent assay (ELISA), and the levels of AMPK, phosphorylated (p)-AMPK, and NF-κB proteins in the sciatic nerve were measured by Western blot. ResultThe blood glucose concentration and TWL in the model group were higher than those in the normal group at each time point (P<0.01). The levels of IL-1β, TNF-α, and NF-κB protein in sciatic nerve in the model group were higher than those in the normal group (P<0.01), and the p-AMPK/AMPK ratio was smaller than that in the normal group (P<0.01). Compared with the model group, TBK of the three doses lowered the TWL (P<0.05, P<0.01) and the levels of IL-1β, TNF-α, and NF-κB protein in sciatic nerve of rats (P<0.05, P<0.01), and high-dose and medium-dose TBK raised p-AMPK/AMPK (P<0.05, P<0.01). The sciatic nerve fibers were orderly and compact with alleviation of demyelination in rats treated with TBK compared with those in the model group. ConclusionTBK improves the function of sciatic nerve and alleviates neuroinflammation in diabetic rats. The mechanism is the likelihood that it up-regulates the expression of AMPK in the AMPK/NF-κB pathway and inhibits the expression of downstream NF-κB, thereby alleviating the neuroinflammation caused by high levels of inflammatory factors such as IL-1β and TNF-α due to NF-κB activation.
9.Role of p38 MAPK Pathway in Diabetic Peripheral Neuropathy and Chinese Medicine Intervention: A Review
Peng YANG ; Chengfei ZHANG ; Yaqi ZHANG ; Chuan PENG ; Qiue ZHANG ; Lili WU ; Lingling QIN ; Tonghua LIU ; Xiaohong MU
Chinese Journal of Experimental Traditional Medical Formulae 2023;29(9):99-108
Diabetic peripheral neuropathy (DPN) is a symptom and/or sign of peripheral nerve dysfunction that occurs in patients with diabetes mellitus when other causes are excluded. DPN, one of the most common complications of diabetes mellitus, can lead to disability, foot ulcers, and amputation at a later stage. Its pathogenesis is closely related to high glucose-induced inflammatory damage, oxidative stress, mitochondrial disorders, and apoptosis in neural tissues. The p38 mitogen-activated protein kinase (p38 MAPK) signaling pathway is a key mechanism mediating the expression of inflammatory factors, oxidative factors, and apoptotic factors of neural tissues in DPN. The inflammatory response, oxidative stress damage, and apoptosis, induced by the activation of p38 MAPK phosphorylation by factors such as high glucose, can cause cell lipid peroxidation, protein modification, and nucleic acid damage, which results in axonal degeneration and demyelination changes. The current treatment of DPN with western medicine has obvious shortcomings such as adverse effects and addictive tendencies. In recent years, the research on traditional Chinese medicine (TCM) in the prevention and treatment of DPN has gradually increased, and the exploration of Chinese medicine intervention in the p38 MAPK pathway transduction to improve DPN has advanced. The present study reviewed the relations of the p38 MAPK pathway with insulin resistance and peripheral neuropathy and summarized the molecular biological mechanisms involved in the pathological process of DPN, such as inflammation regulation, oxidative stress, polyol pathway regulation, and Schwann cell apoptosis in the past 10 years. In addition, the literature on Chinese medicine monomers, Chinese patent medicines, and Chinese medicine compounds in inhibiting inflammatory reactions, oxidative injury, and apoptosis of DPN peripheral nerves based on the p38 MAPK pathway, resisting axonal degeneration and demyelination changes, improving sensory and motor abnormalities, relieving peripheral pain sensitization, and facilitating nerve conduction mechanism to provide references for the development of new drugs for clinical prevention and treatment of DPN.
10.Mechanisms of Saponins in Chinese Medicinals Against Diabetic Nephropathy: A Review
Peng YANG ; Tonghua LIU ; Lili WU ; Lingling QIN ; Chengfei ZHANG ; Chuan PENG ; Qiue ZHANG
Chinese Journal of Experimental Traditional Medical Formulae 2023;29(4):263-271
Diabetic nephropathy (DN), the most feared microvascular complication of diabetes and one of the most common and serious complications of diabetes, is the major cause of end-stage renal disease worldwide, leading cause of morbidity and mortality in patients with diabetes, and the main non-communicable cause of death worldwide. There are many types of saponins, which are the main bioactive components of various Chinese medicinals. They have various pharmacological activities such as lowering blood glucose and blood lipids, improving insulin resistance, anti-inflammation, anti-oxidative stress, anti-tumor, and immune modulation. In recent years, it has been frequently verified that the saponins in Chinese medicinals have definite effect in regulating DN, showing multi-target, multi-pathway, multi-system, multi-effect characteristics. Thus, they have broad prospects in the prevention and treatment of this disease. There has been an explosion of research on the treatment of DN with saponins in Chinese medicinals in vivo and in vitro, but there is a lack of systematic and comprehensive summary. Therefore, this study summed up the studies of saponins in Chinese medicinals in the intervention of DN and summarized the mechanisms such as improving glucolipid metabolism, inhibiting oxidative stress, anti-inflammation, anti-apoptosis, regulating autophagy, anti-fibrosis, and protecting podocytes, with a view to providing ideas and references for the development of drugs related to DN.

Result Analysis
Print
Save
E-mail