OBJECTIVE: To investigate the effect of moxibustion on central insulin resistance related proteins of the rats suffering from diabetic cognitive decline, and analyze the underlying mechanism of moxibustion for cognition improvement. METHODS: Using the intraperitoneal injection of STZ combined with a high-fat diet, the rat model of diabetic cognitive decline were prepared. Twenty successfully-modeled rats were assigned randomly into a model group and a moxibustion group, 10 rats in each one. Besides, a blank group was set up with 10 rats collected. In the moxibustion group, suspending moxibustion was applied to "Baihui" (GV20), "Shenting" (GV24) and "Dazhui" (GV14) at the same time, 20 min in each intervention, once a day, and 6 interventions were delivered weekly and the duration of treatment was consecutive 4 weeks. The random blood glucose was measured using glucometer, and the learning-memory ability was detected by water maze test. HE staining was used to observe the morphology of neurons in the hippocampal tissue, real-time PCR assay was to detect mRNA expression of insulin receptor substrate 1 (IRS1), phosphatidylinositol 3-kinase (PI3K) and protein kinase B (AKT) in the hippocampal tissue. The Western blot method was employed to detect the protein expression of IRS1, PI3K, AKT, phosphorylated IRS1 (p-IRS1), phosphorylated PI3K (p-PI3K) and phosphorylated AKT (p-AKT) in the hippocampal tissue, and the ratio of p-IRS1/IRS1, p-PI3K/PI3K and p-AKT/AKT was calculated separately. The immunofluorescence intensity of p-IRS1, p-PI3K, and p-AKT was measured using immunofluorescence. RESULTS: Compared with the blank group, the rats of the model group exhibited higher random blood glucose (P<0.001), longer escape latency (P<0.001), severe pathological damage in the hippocampus, lower mRNA expression of IRS1, PI3K, and AKT (P<0.001), reduced ratio of p-IRS1/IRS1, p-PI3K/PI3K and p-AKT/AKT (P<0.001), and declined immunofluorescence intensity of p-IRS1, p-PI3K, and p-AKT in the hippocampal tissue (P<0.001). In comparison with the model group, for the rats of the moxibustion group, the random blood glucose decreased (P<0.05), the escape latency was shortened (P<0.01), the hippocampal pathological damage was attenuated, the mRNA expression of IRS1, PI3K and AKT increased (P<0.01), the ratio of p-IRS1/IRS1, p-PI3K/PI3K and p-AKT/AKT was elevated (P<0.01, P<0.05), and the immunofluorescence intensity of p-IRS1, p-PI3K, and p-AKT in the hippocampal tissue was strengthened (P<0.01, P<0.05). CONCLUSION In diabetic rats experiencing cognitive decline, moxibustion can enhance the learning-memory ability, which may be attributed to modulating the protein expression of IRS1, PI3K, and AKT, and their phosphorylation, activating insulin signal transduction, and reducing central insulin resistance.
Animals ; Moxibustion ; Insulin Resistance ; Rats ; Male ; Insulin Receptor Substrate Proteins/genetics* ; Rats, Sprague-Dawley ; Humans ; Proto-Oncogene Proteins c-akt/genetics* ; Cognitive Dysfunction/genetics* ; Diabetes Mellitus, Experimental/therapy* ; Hippocampus/metabolism* ; Acupuncture Points ; Phosphatidylinositol 3-Kinases/genetics*

OBJECTIVE: To investigate the effect of Tongmai Hypoglycemic Capsule (THC) on myocardium injury in diabetic cardiomyopathy (DCM) rats. METHODS: A total of 24 Sprague Dawley rats were fed for 4 weeks with high-fat and high-sugar food and then injected with streptozotocin intraperitoneally for the establishment of the DCM model. In addition, 6 rats with normal diets were used as the control group. After modeling, 24 DCM rats were randomly divided into the model, L-THC, M-THC, and H-THC groups by computer generated random numbers, and 0, 0.16, 0.32, 0.64 g/kg of THC were adopted respectively by gavage, with 6 rats in each group. After 12 weeks of THC administration, echocardiography, histopathological staining, biochemical analysis, and Western blot were used to detect the changes in myocardial structure, oxidative stress (OS), biochemical indexes, protein expressions of myocardial fibrosis, and nuclear factor erythroid 2-related faactor 2 (Nrf2) element, respectively. RESULTS: Treatment with THC significantly decreased cardiac markers such as creatine kinase, lactate dehydrogenase, and creatine kinase-MB, etc., (P<0.01); enhanced cardiac function indicators including heart rate, ejection fraction, cardiac output, interventricular septal thickness at diastole, and others (P<0.05 or P<0.01); decreased levels of biochemical indicators such as fasting blood glucose, total cholesterol, triglycerides, low-density lipoprotein cholesterol, aspartate transaminase, (P<0.05 or P<0.01); and decreased the levels of myocardial fibrosis markers α-smooth muscle actin (α-SMA), and collagen I (Col-1) protein (P<0.01), improved myocardial morphology and the status of myocardial interstitial fibrosis. THC significantly reduced malondialdehyde levels in model rats (P<0.01), increased levels of catalase, superoxide dismutase, and glutathione (P<0.01), and significantly increased the expression of Nrf2, NAD(P)H:quinone oxidoreductase 1, heme oxygenase-1, and superoxide dismutase 2 proteins in the left ventricle of rats (P<0.01). CONCLUSION THC activates the Nrf2 signaling pathway and plays a protective role in reducing OS injury and cardiac fibrosis in DCM rats.
Animals ; Diabetic Cardiomyopathies/physiopathology* ; Oxidative Stress/drug effects* ; Drugs, Chinese Herbal/therapeutic use* ; Rats, Sprague-Dawley ; Myocardium/metabolism* ; Fibrosis ; Male ; Capsules ; Hypoglycemic Agents/therapeutic use* ; NF-E2-Related Factor 2/metabolism* ; Rats ; Diabetes Mellitus, Experimental/drug therapy*

OBJECTIVES: To investigate the therapeutic mechanism of Danzhi Jiangtang Capsule (DZJTC) for repairing renal vascular endothelial injury in rats with diabetic nephropathy (DN). METHODS: Fifty male SD rat models of DN, established by left nephrectomy, high-sugar and high-fat diet and streptozotocin injection, were randomized into DN model group, low-, medium-, and high-dose DZJTC treatment groups, and DAPT (a γ-secretase inhibitor) treatment group, with 10 rats with normal feeding as the control group. DZJTC was administered by daily gavage at 0.315, 0.63, or 1.26 g/kg, and DAPT (20 mg/kg, dissolved in 50% CMC-Na solution) was given by gavage every other day for 4 weeks; normal saline was given in the control and model groups. After treatment, the levels of creatinine (CRE), blood urea nitrogen (BUN), and microalbuminuria (mALB) were detected with ELISA, and renal pathologies were observed by transmission electron microscopy. Renal expressions of vascular endothelial growth factor (VEGF) and endothelin-1 (ET-1) were measured by immunohistochemistry, and the protein expressions of CD31 and Notch signaling pathway components were detected using Western blotting. RESULTS: The rat models of DN showed significantly increased CRE, BUN, and mALB levels, obvious renal pathologies under electron microscopy, increased renal VEGF, ET-1 and CD31 expressions, and upregulated Notch1, NICD, and MAML1 protein levels. Treatment with DZJTC at the 3 doses and DAPT significantly reduced CRE, BUN, and mALB levels, improved renal pathology, decreased VEGF, ET-1 and CD31 expressions, and lowered Notch1, NICD and MAML1 levels, and the effects were the most pronounced with high-dose DZJTC. CONCLUSIONS DZJTC ameliorates hyperproliferation and dysfunction of renal vascular endothelium in DN rats possibly by regulating renal VEGF and ET-1 levels via inhibiting NICD- and MAML1-mediated Notch signaling pathway.
Animals ; Male ; Drugs, Chinese Herbal/therapeutic use* ; Rats ; Rats, Sprague-Dawley ; Signal Transduction/drug effects* ; Diabetic Nephropathies/drug therapy* ; Receptor, Notch1/metabolism* ; Kidney/blood supply* ; Diabetes Mellitus, Experimental ; Down-Regulation ; Endothelium, Vascular/metabolism* ; Nuclear Proteins/metabolism*

OBJECTIVE: Diabetes-induced gastrointestinal (GI) motility disorders are increasingly prevalent. Damage to the enteric nervous system (ENS), composed primarily of enteric neurons and glial cells, is an essential mechanism involved in these disorders. Although electroacupuncture (EA) has shown the potential to mitigate enteric neuronal loss, its mechanism is not fully understood. Additionally, the effects of EA on enteric glial cells have not been investigated. Enteric neural precursor cells (ENPCs) contribute to the structural and functional integrity of the ENS, yet whether EA enhances their differentiation into enteric neurons and glial cells remains unexplored. This study investigates whether EA promotes ENS repair through enhancing ENPC-derived neurogenesis and gliogenesis and elucidates the potential molecular mechanisms involved. METHODS: Transgenic mice were used to trace Nestin⁺/nerve growth factor receptor (Ngfr)⁺ ENPCs labeled with green fluorescent protein (GFP) in vivo. Mice were randomly divided into four groups: control, diabetes mellitus (DM), DM + sham EA, and DM + EA. The effects of EA on diabetic mice were evaluated by GI motility, ENS structure, and ENPC differentiation. Glial cell line-derived neurotrophic factor (GDNF)/Ret signaling was detected to clarify the underlying molecular mechanisms. RESULTS: EA alleviated diabetes-induced GI motility disorders, as indicated by reduced whole gut transit time, shortened colonic bead expulsion time, and enhanced smooth muscle contractility. Furthermore, EA attenuated diabetes-induced losses of enteric neurons and glial cells, thereby restoring ENS integrity. Notably, EA reversed the diabetes-induced decrease in ENPCs and significantly increased the absolute number and the proportion of ENPC-derived enteric neurons. However, immunofluorescence analyses revealed no colocalization between EA-induced glial fibrillary acidic protein⁺ glial cells and GFP-labeled ENPCs. Mechanistically, GDNF/Ret signaling was elevated in intestinal tissues and upregulated in ENPCs in EA-treated diabetic mice. CONCLUSION EA facilitates ENS repair by promoting Nestin⁺/Ngfr⁺ ENPC differentiation into enteric neurons via upregulation of GDNF/Ret signaling, and driving enteric gliogenesis from non-Nestin⁺/Ngfr⁺ ENPCs. These findings highlight EA's role in ameliorating diabetes-induced GI dysmotility through ENPC-derived ENS restoration. Please cite this article as: Guo JL, Liu S, Ding SJ, Yang X, Du F. Electroacupuncture at ST36 improves gastrointestinal motility disorders by promoting enteric nervous system regeneration through GDNF/Ret signaling in diabetic mice. J Integr Med. 2025; 23(5):548-559.
Animals ; Electroacupuncture ; Enteric Nervous System/physiology* ; Gastrointestinal Motility/physiology* ; Glial Cell Line-Derived Neurotrophic Factor/metabolism* ; Diabetes Mellitus, Experimental/therapy* ; Signal Transduction ; Mice ; Gastrointestinal Diseases/physiopathology* ; Proto-Oncogene Proteins c-ret/metabolism* ; Mice, Transgenic ; Male ; Nerve Regeneration ; Neural Stem Cells ; Mice, Inbred C57BL ; Acupuncture Points

Blood glucose fluctuation leads to poor bone defect repair in patients with type 2 diabetes (T2DM). Strategies to safely and efficiently improve the bone regeneration disorder caused by blood glucose fluctuation are still a challenge. Neutral sphingophospholipase 2 (Smpd3) is downregulated in jawbone-derived bone marrow mesenchymal stem cells (BMSCs) from T2DM patients. Here, we investigated the effect of Smpd3 on the osteogenic differentiation of BMSCs and utilized exosomes from stem cells overexpressing Smpd3 as the main treatment based on the glucose responsiveness of phenylboronic acid-based polyvinyl alcohol crosslinkers and the protease degradability of gelatin nanoparticles. The combined loading of Smpd3-overexpressing stem cell-derived exosomes (Exos-Smpd3) and nanosilver ions (Ns) to construct a hydrogel delivery system (Exos-Smpd3@Ns) promoted osteogenesis and differentiation of BMSCs in a glucose-fluctuating environment, ectopic osteogenesis of BMSCs in a glucose-fluctuating environment and jawbone regeneration of diabetic dogs in vitro. Mechanistically, Smpd3 promoted the osteogenesis and differentiation of jawbone-derived BMSCs by activating autophagy in the jawbone and inhibiting macrophage polarization and oxidative stress caused by blood glucose fluctuations. These results reveal the role and mechanism of Smpd3 and the Smpd3 overexpression exosome delivery system in promoting BMSC function and bone regeneration under blood glucose fluctuations, providing a theoretical basis and candidate methods for the treatment of bone defects in T2DM patients.
Exosomes ; Animals ; Bone Regeneration/drug effects* ; Dogs ; Mesenchymal Stem Cells ; Humans ; Blood Glucose ; Cell Differentiation ; Osteogenesis/drug effects* ; Diabetes Mellitus, Type 2/therapy* ; Diabetes Mellitus, Experimental ; Cells, Cultured ; Hydrogels ; Male

This study investigated the effect of Lianmei Qiwu Decoction(LMQWD) on the improvement of cardiac autonomic nerve remodeling in the diabetic rat model induced by the high-fat diet and explored the underlying mechanism of LMQWD through the AMP-activated protein kinase(AMPK)/tropomyosin receptor kinase A(TrkA)/transient receptor potential melastatin 7(TRPM7) signaling pathway. The diabetic rats were randomly divided into a model group, an LMQWD group, an AMPK agonist group, an unloaded TRPM7 adenovirus group(TRPM7-N), an overexpressed TRPM7 adenovirus group(TRPM7), an LMQWD + unloaded TRPM7 adenovirus group(LMQWD+TRPM7-N), an LMQWD + overexpressed TRPM7 adenovirus group(LMQWD+TRPM7), and a TRPM7 channel inhibitor group(TRPM7 inhibitor). After four weeks of treatment, programmed electrical stimulation(PES) was employed to detect the arrhythmia susceptibility of rats. The myocardial cell structure and myocardial tissue fibrosis of myocardial and ganglion samples in diabetic rats were observed by hematoxylin-eosin(HE) staining and Masson staining. The immunohistochemistry, immunofluorescence, real-time quantitative polymerase chain reaction(RT-PCR), and Western blot were adopted to detect the distribution and expression of TRPM7, tyrosine hydroxylase(TH), choline acetyltransferase(ChAT), growth associated protein-43(GAP-43), nerve growth factor(NGF), p-AMPK/AMPK, and other genes and related neural markers. The results showed that LMQWD could significantly reduce the arrhythmia susceptibility and the degree of fibrosis in myocardial tissues, decrease the levels of TH, ChAT, and GAP-43 in the myocardium and ganglion, increase NGF, inhibit the expression of TRPM7, and up-regulate p-AMPK/AMPK and p-TrkA/TrkA levels. This study indicated that LMQWD could attenuate cardiac autonomic nerve remodeling in the diabetic state, and its mechanism was associated with the activation of AMPK, further phosphorylation of TrkA, and inhibition of TRPM7 expression.
Rats ; Animals ; AMP-Activated Protein Kinases/metabolism* ; Nerve Growth Factor/metabolism* ; Diabetes Mellitus, Experimental/drug therapy* ; TRPM Cation Channels/metabolism* ; GAP-43 Protein/metabolism* ; Signal Transduction ; Diabetic Neuropathies/genetics* ; Fibrosis

Objective To investigate the neuroprotective effect of methylene blue on diabetic retinopathy in rats. Methods Thirty SD rats were randomly divided into blank, control and experimental groups. The control and experimental groups were induced with diabetes by streptozotocin (STZ) intraperitoneal injection. After 6 weeks of successful modeling, the experimental group received intravitreal injection of methylene blue at a dose of [0.2 mg/(kg.d)], while the control group received an equal amount of dimethyl sulfoxide (DMSO) intravitreal injection, both continuously injected for 7 days. ELISA was used to detect the levels of retinal superoxide dismutase (SOD), 8-iso-prostaglandin F2alpha (iPF2α) and interleukin-1β (IL-1β) in rats. Western blot analysis was used to detect the expression of retinal extracellular signal-regulated kinase 1/2 phosphorylation (p-ERK1/2) and phosphorylated protein kinase B (p-AKT), and PAS staining was used to detect retinal morphological changes. Results Compared with the blank group rats, the retinal SOD activity in the control and experimental group rats was significantly reduced. iPF2α, IL-1β and p-ERK1/2 level increased, while p-AKT level decreased. Compared with the control group, the SOD activity of the experimental group rats increased. iPF2α and IL-1β level went down, while p-ERK1/2 and p-AKT level went up significantly. The overall thickness of the retinal layer and the number of retinal ganglion cells were significantly reduced. Conclusion Methylene blue improves diabetic retinopathy in rats by reducing retinal oxidative stress and enhancing ERK1/2 and AKT phosphorylation.
Rats ; Animals ; Diabetic Retinopathy/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; Mitogen-Activated Protein Kinase 3/metabolism* ; Interleukin-1beta/metabolism* ; Methylene Blue/pharmacology* ; Phosphorylation ; Rats, Sprague-Dawley ; MAP Kinase Signaling System ; Diabetes Mellitus, Experimental/drug therapy* ; Superoxide Dismutase/metabolism*

OBJECTIVES: To investigate the effects and molecular mechanisms of asiatic acid on β-cell function in type 2 diabetes mellitus (T2DM). METHODS: The T2DM model was established by high fat diet and streptozotocin injection in ICR mice, and the effects of asiatic acid on glucose regulation were investigated in model mice. The islets were isolated from palmitic acid-treated diabetic mice. ELISA was used to detect the glucose-stimulated insulin secretion, tumor necrosis factor (TNF)-α and interleukin (IL)-6. ATP assay was applied to measure ATP production, and Western blotting was used to detect protein expression of mature β cell marker urocortin (Ucn) 3 and mitofusin (Mfn) 2. The regulatory effects of asiatic acid on glucose-stimulated insulin secretion (GSIS) and Ucn3 expression were also investigated after siRNA interference with Mfn2 or treatment with TNF-α. RESULTS: Asiatic acid with the dose of 25 mg·kg^－1·d^－1 had the best glycemic control in T2DM mice and improved the homeostasis model assessment β index. Asiatic acid increased the expression of Mfn2 and Ucn3 protein and improved the GSIS function of diabetic β cells in vitro and in vivo (both P<0.05). Moreover, it improved the ATP production of islets of T2DM mice in vitro (P<0.05). Interfering Mfn2 with siRNA blocked the up-regulation of Ucn3 and GSIS induced by asiatic acid. Asiatic acid inhibited islet TNF-α content and increased Mfn2 and Ucn3 protein expression inhibited by TNF-α. CONCLUSIONS Asiatic acid improves β cell insulin secretion function in T2DM mice by maintaining the β cell maturity, which may be related to the TNF-α/Mfn2 pathway.
Mice ; Animals ; Insulin Secretion ; Diabetes Mellitus, Type 2/drug therapy* ; Islets of Langerhans/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Insulin/therapeutic use* ; Diabetes Mellitus, Experimental ; Mice, Inbred ICR ; Glucose/therapeutic use* ; Interleukin-6/metabolism* ; RNA, Small Interfering/pharmacology* ; Adenosine Triphosphate ; GTP Phosphohydrolases/therapeutic use*

Tu-Xian decoction (TXD), a traditional Chinese medicine (TCM) formula, has been frequently administered to manage diabetic cognitive impairment (DCI). Despite its widespread use, the mechanisms underlying TXD's protective effects on DCI have yet to be fully elucidated. As a significant regulator in neurodegenerative conditions, death-associated protein kinase-1 (DAPK-1) serves as a focus for understanding the action of TXD. This study was designed to whether TXD mediates its beneficial outcomes by inhibiting DAPK-1. To this end, a diabetic model was established using Sprague-Dawley (SD) rats through a high-fat, high-sugar (HFHS) diet regimen, followed by streptozotocin (STZ) injection. The experimental cohort was stratified into six groups: Control, Diabetic, TC-DAPK6, high-dose TXD, medium-dose TXD, and low-dose TXD groups. Following a 12-week treatment period, various assessments-including blood glucose levels, body weight measurements, Morris water maze (MWM) testing for cognitive function, brain magnetic resonance imaging (MRI), and histological analyses using hematoxylin-eosin (H&E), and Nissl staining-were conducted. Protein expression in the hippocampus was quantified through Western blotting analysis. The results revealed that TXD significantly improved spatial learning and memory abilities, and preserved hippocampal structure in diabetic rats. Importantly, TXD administration led to a down-regulation of proteins indicative of neurological damage and suppressed DAPK-1 activity within the hippocampal region. These results underscore TXD's potential in mitigating DCIvia DAPK-1 inhibition, positioning it as a viable therapeutic candidate for addressing this condition. Further investigation into TXD's molecular mechanisms may elucidate new pathways for the treatment of DCI.
Animals ; Rats ; Brain/metabolism* ; Cognitive Dysfunction/drug therapy* ; Diabetes Mellitus, Experimental/metabolism* ; Hippocampus ; Rats, Sprague-Dawley

The dry root and rhizome of Panax ginseng C. A. Mey has garnered much interest owing to its medicinal properties against diabetes and cardiovascular diseases. In this study, an ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS)-based metabolomics approach was used to illustrate the therapeutic mechanisms of ginseng extract on the serum and urinary metabolic profiles in streptozotocin-induced type 1 diabetes mellitus (T1DM) rats. Pharmacological and renal parameters in response to the administration of ginseng were also evaluated. In total, 16 serum endogenous metabolites and 14 urine endogenous metabolites, including pyruvic acid, indoleacetic acid, and phenylacetylglycine, were identified as potential biomarkers for diabetes. Pathway enrichment and network analysis revealed that the biomarkers modulated by ginseng were primarily involved in phenylalanine and pyruvate metabolism, as well as in arginine biosynthesis. Moreover, the levels of several renal injury-related biomarkers in T1DM rats were significantly restored following treatment with ginseng. The administration of the extract helped maintain tissue structure integrity and ameliorated renal injury. The findings suggest that the regulatory effect of ginseng extract on T1DM involves metabolic management of diabetic rats, which subsequently attenuates T1DM-induced early renal dysfunction.
Animals ; Biomarkers ; Chromatography, High Pressure Liquid/methods* ; Diabetes Mellitus, Experimental/metabolism* ; Diabetes Mellitus, Type 1/drug therapy* ; Kidney ; Metabolomics/methods* ; Panax/chemistry* ; Plant Extracts/pharmacology* ; Rats