Injection Of Streptozocin Research Articles

Antidiabetic effects of aqueous leaf extract of Vernonia amygdalina on serum liver markers in streptozotocin-induced diabetic albino Rats: a new data to support its Anti-diabetic effect

BackgroundNumerous plants have been explored for their potential antidiabetic properties, and Vernonia amygdalina (VA) stands among them. This study aims to investigate the antidiabetic activities of VA and validate its efficacy.MethodsAn aqueous extract of Vernonia amygdalina leaves was obtained through maceration. The antidiabetic effects of this plant extract were evaluated in vivo using diabetic model rats. Albino Wistar rats were induced into a diabetic state through intraperitoneal injection of streptozocin and subsequently treated with an optimal dose of 250 mg/kg aqueous extract of VA over a 21-day period. Parameters such as body weight, blood glucose levels, and serum marker enzymes were measured.ResultsThe results demonstrated a significant reduction (p < 0.05) in the glucose levels of streptozocin-induced diabetic rats following treatment with VA extract, highlighting its potential as an antidiabetic agent that performed comparably to the reference drug, glimepiride. Additionally, a significant increase (p < 0.05) in the body weight of the treated diabetic rats was observed. Aqueous extracts also significantly (p < 0.05) altered the serum concentrations of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in a manner similar to the glimepiride-treated group.ConclusionThis study affirms the anti-diabetic effects of the aqueous extract of Vernonia amygdalina in streptozotocin-induced diabetic rats and suggests that the extract holds promise as an important phytomedicine for the development of more effective treatments for diabetes.

Irisin alleviates the pyroptosis of β cells in T2DM by inhibiting NLRP3 inflammasome through regulating miR-19b-3p/SOCS3/STAT3 axis mediated autophagy.

The purpose of this study was to analyze the mechanism by which irisin affects β-cell pyroptosis in type 2 diabetes mellitus (T2DM). The in vivo T2DM model was established by raised with high-fat diet and intraperitoneally injection of streptozocin. Min6 cells were divided into four groups: negative control (NC), high glucose (HG), HG + irisin, and HG + irisin+3-MA. The cell viability was determined by CCK-8 assay. Dual-luciferase gene reporter assay was conducted to confirm the binding between miR-19b-3p and SOCS3. The expression level of FNDC5 and GSDMD was visualized using the immunofluorescence assay. The protein level of FNDC5, Beclin1, LC3II/I, NLRP3, cleaved-caspase-1, GSDMD-N, STAT3, p-STAT3, and SOCS3 was determined by Western blotting. The secretion of irisin, lactate dehydrogenase (LDH), and insulin was checked by ELISA. In vivo results showed that pathological changes in islet tissues with declined number of β cells, elevated FBG value, decreased FIN and HOMA-β value, elevated autophagy-associated proteins expressions, and activated NLRP3 signaling in T2DM mice, which were dramatically reversed by FNDC5 overexpression. Furthermore, the declined level of miR-19b-3p and p-STAT3, as well as the upregulation of SOCS3, was greatly rescued by FNDC5 overexpression. The in vitro data confirmed the binding site between SOCS3 and miR-19b-3p. SOCS3 was downregulated and p-STAT3 was upregulated in miR-19b-3p mimic-treated Min6 cells. In HG-stimulated Min6 cells, the elevated cell viability, increased production of insulin, decreased release of LDH, and inactivated NLRP3 signaling induced by irisin were abolished by miR-19b-3p inhibitor and STAT3 inhibitor. The increased level of autophagy-related proteins and activated SOCS3/STAT3 axis induced by irisin in HG-stimulated Min6 cells were abolished by miR-19b-3p inhibitor. The inhibitory effect of irisin against NLRP3 signaling in HG-stimulated Min6 cells was abrogated by 3-MA. In conclusion, irisin alleviated the pyroptosis of β cells in T2DM by inhibiting NLRP3 signaling through miR-19b-3p/SOCS3/STAT3 axis mediated autophagy.

Chinese medicine Linggui Zhugan formula protects against diabetic kidney disease in close association with inhibition of proteinase 3-mediated podocyte apoptosis in mice

Ethnopharmacological relevanceLinggui-Zhugan (LGZG) comprises four herbs and is a classic formula in traditional Chinese medicine. There is strong clinical evidence of its pleiotropic effects in the prevention of diabetes and its related complications. Although several classes of drugs are currently available for clinical management of diabetic kidney disease (DKD), tight glycemic and/or hypertension control may not prevent disease progression. This study evaluated the therapeutic effect of the ethnopharmacological agent LGZG on DKD. Aim of the studyThis study aimed to investigate the effects of LGZG formula with standard quality control on experimental DKD and its related metabolic disorders in animal model. Meanwhile, the present study aimed to investigate regulatory effects of LGZG on renal proteinase 3 (PR3) to reveal mechanisms underlying renoprotective benefits of LGZG. Materials and methodsLGZG decoction was fingerprinted by high-performance liquid chromatography for quality control. An experimental model of DKD was induced in C57 BL/6J mice by a combination of high-fat diet feeding, uninephrectomy, and intraperitoneal injection of streptozocin. The LGZG decoction was administrated by daily oral gavage. ResultsTreatment with LGZG formula significantly attenuated DKD-like traits (including severe albuminuria, mesangial matrix expansion, and podocyte loss) and metabolic dysfunction (disordered body composition and dyslipidemia) in mice. RNA sequencing data revealed a close association of LGZG treatment with marked modulation of signaling pathways related to podocyte injury and cell apoptosis. Mechanistically, LGZG suppressed the DKD-triggered increase in renal PR3 and podocyte apoptosis. In-vitro incubation of mouse immortalized podocytes with LGZG-medicated serum attenuated PR3-mediated apoptosis. ConclusionOur data demonstrated that the LGZG formula protected against DKD in mice and was closely associated with its inhibitory effects on PR3-mediated podocyte apoptosis.

Mitofusin 2 inhibits high glucose-induced apoptosis of human lens epithelial cells via modulating mitochondrial function and autophagy.

Diabetic cataract (DC) is a common ocular complication of diabetes. Mitofusin 2 (MFN2), a mitochondrial fusion protein, is involved in the pathogenesis of cataract and diabetic complications. However, its role and molecular mechanisms in DC remain unclear. DC models in rats were induced by intraperitoneal injection of streptozocin (STZ) for 12 weeks. We measured the body weight of rats, blood glucose concentrations, sorbitol dehydrogenase (SDH) activity and advanced glycation end products (AGE) content in the lenses of rats. MFN2 mRNA and protein expression levels in the lenses were detected by RT-qPCR and western blot assays. In vitro, human lens epithelial (HLE) B3 cells were treated for 48 h with 25 mM glucose (high glucose, HG) to induce cell damage. To determine the role of MFN2 in HG-induced cell damage, HLE-B3 cells were transfected with lentivirus loaded with MFN2 overexpression plasmid or short hairpin RNA (shRNA) to overexpress or knock down MFN2 expression, followed by HG exposure. Cell viability was assessed by CCK-8 assay. Flow cytometry was used to detect cell apoptosis and reactive oxygen species (ROS) level. JC-1 staining showed the changes in mitochondrial membrane potential (Δψm). The mediators related to apoptosis, mitochondrial damage, and autophagy were determined. STZ-administrated rats showed reduced body weight, increased blood glucose levels, elevated SDH activity and AGE content, suggesting successful establishment of the DC rat model. Interestingly, MFN2 expression was significantly downregulated in DC rat lens and HG-induced HLE-B3 cells. Further analysis showed that under HG conditions, MFN2 overexpression enhanced cell viability and inhibited apoptosis accompanied by decreased Bax, cleaved caspase-9 and increased Bcl-2 expression in HLE-B3 cells. MFN2 overexpression also suppressed the mitochondrial damage elicited by HG as manifested by reduced ROS production, recovered Δψm and increased mitochondrial cytochrome c (Cyto c) level. Moreover, MFN2 overexpression increased LC3BⅡ/LC3BⅠ ratio and Beclin-1 expression, but decreased p62 level, and blocked the phosphorylation of mTOR in HG-treated HLE-B3 cells. In contrast, MFN2 silencing exerted opposite effects. Presented findings indicate that MFN2 expression may be essential for preventing lens epithelial cell apoptosis during development of diabetic cataract.

ENAMPT is a novel therapeutic target for mitigation of coronary microvascular disease in type 2 diabetes

Aims/hypothesisIndividuals with diabetes are at high risk of cardiovascular complications, which significantly increase morbidity/mortality. Coronary microvascular disease (CMD) is recognised as a critical contributor to the increased cardiac mortality observed in people with diabetes. Therefore, there is an urgent need for treatments that are specific to CMD. eNAMPT (extracellular nicotinamide phosphoribosyltransferase) is a damage-associated molecular pattern and TLR4 ligand, whose plasma levels are elevated in people with diabetes. This study was thus designed to investigate the pathogenic role of intracellular nicotinamide phosphoribosyltransferase (iNAMPT) and eNAMPT in promoting the development of CMD in a preclinical murine model of type 2 diabetes.MethodsAn inducible type 2 diabetic mouse model was generated by a single injection of low-dose streptozocin (75 mg/kg, i.p.) combined with a high-fat diet for 16 weeks. The in vivo effects of i/eNAMPT inhibition on cardiac endothelial cell (CEC) function were evaluated by using Nampt+/− heterozygous mice, chronic administration of eNAMPT-neutralising monoclonal antibody (mAb) or use of an NAMPT enzymatic inhibitor (FK866).ResultsAs expected, diabetic wild-type mice exhibited significantly lower coronary flow velocity reserve (CFVR), a determinant of coronary microvascular function, compared with control wild-type mice. eNAMPT plasma levels or expression in CECs were significantly greater in diabetic mice than in control mice. Furthermore, in comparison with diabetic wild-type mice, diabetic Nampt+/− heterozygous mice showed markedly improved CFVR, accompanied by increased left ventricular capillary density and augmented endothelium-dependent relaxation (EDR) in the coronary artery. NAMPT inhibition by FK866 or an eNAMPT-neutralising mAb significantly increased CFVR in diabetic mice. Furthermore, administration of the eNAMPT mAb upregulated expression of angiogenesis- and EDR-related genes in CECs from diabetic mice. Treatment with either eNAMPT or NAD+ significantly decreased CEC migration and reduced EDR in coronary arteries, partly linked to increased production of mitochondrial reactive oxygen species.Conclusions/interpretationThese data indicate that increased i/eNAMPT expression contributes to the development of diabetic coronary microvascular dysfunction, and provide compelling support for eNAMPT inhibition as a novel and effective therapeutic strategy for CMD in diabetes.Graphical

The role of PCSK9 in glomerular lipid accumulation and renal injury in diabetic kidney disease.

Glomerular lipid accumulation is a defining feature of diabetic kidney disease (DKD); however, the precise underlying mechanism requires further elucidation. Recent evidence suggests a role for proprotein convertase subtilisin/kexin type 9 (PCSK9) in intracellular lipid homeostasis. Although PCSK9 is present in kidneys, its role within kidney cells and relevance to renal diseases remain largely unexplored. Therefore, we investigated the role of intracellular PCSK9 in regulating lipid accumulation and homeostasis in the glomeruli and podocytes under diabetic conditions. Furthermore, we aimed to identify the pathophysiological mechanisms responsible for the podocyte injury that is associated with intracellular PCSK9-induced lipid accumulation in DKD. In this study, glomeruli were isolated from human kidney biopsy tissues, and glomerular gene-expression analysis was performed. Also, db/db and db/m mice were used to perform glomerular gene-expression profiling. We generated DKD models using a high-fat diet and low-dose intraperitoneal streptozocin injection in C57BL/6 and Pcsk9 knockout (KO) mice. We analysed cholesterol and triacylglycerol levels within the kidney cortex. Lipid droplets were evaluated using BODIPY staining. We induced upregulation and downregulation of PCSK9 expression in conditionally immortalised mouse podocytes using lentivirus and siRNA transfection techniques, respectively, under diabetic conditions. A significant reduction in transcription level of PCSK9 was observed in glomeruli of individuals with DKD. PCSK9 expression was also reduced in podocytes of animals under diabetic conditions. We observed significantly higher lipid accumulation in kidney tissues of Pcsk9 KO DKD mice compared with wild-type (WT) DKD mice. Additionally, Pcsk9 KO mouse models of DKD exhibited a significant reduction in mitochondria number vs WT models, coupled with a significant increase in mitochondrial size. Moreover, albuminuria and podocyte foot process effacement were observed in WT and Pcsk9 KO DKD mice, with KO DKD mice displaying more pronounced manifestations. Immortalised mouse podocytes exposed to diabetic stimuli exhibited heightened intracellular lipid accumulation, mitochondrial injury and apoptosis, which were ameliorated by Pcsk9 overexpression and aggravated by Pcsk9 knockdown in mouse podocytes. The downregulation of PCSK9 in podocytes is associated with lipid accumulation, which leads to mitochondrial dysfunction, cell apoptosis and renal injury. This study sheds new light on the potential involvement of PCSK9 in the pathophysiology of glomerular lipid accumulation and podocyte injury in DKD.

Deletion of Nrf2 induced severe oxidative stress and apoptosis in mice model of diabetic bladder dysfunction

The nuclear factor erythroid 2-related factor 2 (Nrf2) pathway has been confirmed as a therapeutic target for type 2 diabetes mellitus (T2DM), however few studies revealed its effect in diabetic bladder dysfunction (DBD). Herein, we reported a Nrf2 deletion diabetic mouse model induced by 8-week high-fat diet feeding combined with streptozocin (STZ) injection in Nrf2 knockout mice. Besides, wild-type mice (WT) were used as control group, wild-type mice with high-fat diet feeding and STZ injection as diabetic group (WT-T2DM), and Nrf2 knockout mice as Nrf2 deletion group (KO). The pathophysiological indexes and bladder morphology showed typical pathological features of diabetic bladder dysfunction in Nrf2 knockout diabetic mouse mice (KO-T2DM). ELISA results showed that advanced glycation end products (AGEs), ROS and malondialdehyde (MDA) levels in bladder was were up-regulated in both WT-T2DM and KO-T2DM group, while superoxide dismutase (SOD) and glutathione (GSH) levels decreased in these two groups. Compared with WT-T2DM group, western blot analysis of the bladder showed down-regulated expression of NQO1 and HO-1 in KO-T2DM group. However, apoptosis, marked by Caspase3 and bax/bcl-2 ratio, was increased in KO-T2DM group. Neurotrophic factor (NGF) was significantly decreased in DBD model, and even much lower in KO-T2DM group. Collectively, our findings demonstrated that deletion of Nrf2 lead to severe oxidative stress, apoptosis, and lower level of neurotrophic factor, and provided the first set of experimental evidence, in a mouse model, to support Nrf2 as a promising target for DBD.

Electroacupuncture improves peripheral neuropathy by up-regulating Sirt1/PGC-1α/TFAM pathway in type 2 diabetes rats with peripheral neuropathy.

To observe the effect of electroacupuncture (EA) on activation of silent information regulator 1 (Sirt1)/peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α)/mitochondrial transcription factor A (TFAM) pathway in type 2 diabetes (T2DM) rats with peripheral neuropathy (DPN) , so as to explore its possible mechanisms underlying improvement of DPN. Thirty male SD rats were randomly divided into blank control group (n=8) and DPN model group (n=22) which were further divided into model group (n=8) and EA group (n=8) after successful modeling. The model of T2DM was established by high-fat diet and low-dose intraperitoneal injection of streptozocin (35 mg/kg). For rats of the EA group (anesthetized with isoflurane), EA stimulation (2 Hz/15 Hz, 2 mA) was applied to "Tianshu"(ST25) for 20 min, once daily, 6 times a week for 6 weeks. The blood glucose level, body weight, area under curve (AUC) of glucose tolerance test, and hind-paw mechanical pain threshold and thermal pain threshold were observed. The intra-epidermal nerve fiber density (IENFD) of the hind-foot pad was observed by immunofluorescence staining. The motor nerve conduction velocity (MNCV) of the sciatic nerve was measured by using electrophysiological method. H.E. staining was used to observe the histopathological changes of the sciatic nerve after modeling. Transmission electron microscopy (TEM) was used to observe the ultrastructural changes of the sciatic nerve. The protein expressions of energy-related Sirt1, PGC-1α and TFAM in the sciatic nerve was detected by Western blot. Compared with the blank control group, the model group had a higher blood glucose contents and AUC (P<0.001), a slower MNCV (P<0.01), and a decrease in the body weight and in the mechanical and thermal pain thresholds (P<0.001) and IENFD (P<0.001), and in the expression levels of Sirt1, PGC-1α and TFAM (P<0.05, P<0.01). In contrast to the model group, the EA group had a decrease in the blood glucose contents and AUC (P<0.05, P<0.01), and an increase in mechanical and thermal pain thresholds, MNCV, IENFD, and expression levels of Sirt1, PGC-1α and TFAM proteins (P<0.01, P<0.05). In addition, results of histopathological and ultrastructural changes of the sciatic nerve showed more fragmented and disordered distribution of axons on the transverse section, and extensive separation of myelin and axons, uneven myelin thickness, axonal degeneration and irregular shape in the model group, whereas in the EA group, the axons on the transverse section were relatively more dense and more complete, the myelin sheath of the sciatic nerve was relatively uniform, and the axonal shape was relatively regular with relatively milder lesions. EA up-regulates the expressions of Sirt1, PGC-1α, TFAM in T2DM rats with DPN, which may be associated with its functions in improving and repairing the injured peripheral nerves in rats with DPN.

Cinnamaldehyde attenuates streptozocin-induced diabetic osteoporosis in a rat model by modulating netrin-1/DCC-UNC5B signal transduction.

Background: Cinnamaldehyde (CMD) is a major functional component of Cinnamomum verum and has shown treatment effects against diverse bone diseases. This study aimed to assess the anti-diabetic osteoporosis (DOP) potential of diabetes mellitus (DM) and to explore the underlying mechanism driving the activity of CMD. Methods: A DOP model was induced via an intraperitoneal injection of streptozocin (STZ) into Sprague-Dawley rats, and then two different doses of CMD were administered to the rats. The effects of CMD on the strength, remodeling activity, and histological structure of the bones were assessed. Changes in the netrin-1 related pathways also were detected to elucidate the mechanism of the anti-DOP activity by CMD. Results: CMD had no significant effect on the body weight or blood glucose level of the model rats. However, the data showed that CMD improved the bone strength and bone remodeling activity as well as attenuating the bone structure destruction in the DOP rats in a dose-dependent manner. The expression of netrin-1, DCC, UNC5B, RANKL, and OPG was suppressed, while the expression of TGF-β1, cathepsin K, TRAP, and RANK was induced by the STZ injection. CMD administration restored the expression of all of these indicators at both the mRNA and protein levels, indicating that the osteoclast activity was inhibited by CMD. Conclusion: The current study demonstrated that CMD effectively attenuated bone impairments associated with DM in a STZ-induced DOP rat model, and the anti-DOP effects of CMD were associated with the modulation of netrin-1/DCC/UNC5B signal transduction.

Protective effect of salidroside on renal damage in diabetic nephropathy mice by regulating RAGE/JAK1/STAT signaling pathway

This study aims to investigate the protective effect of salidroside(SAL) on renal damage in diabetic nephropathy(DN) mice based on the receptor for advanced glycation end products/janus activated kinase 1/signal transduction and activator of transcription 3(RAGE/JAK1/STAT3) signaling pathway. The mouse DN model was established by high-fat/high-sucrose diets combined with intraperitoneal injection of streptozocin(STZ). Mice were randomly divided into normal group, model group, low-dose SAL group(20 mg·kg~(-1)), high-dose SAL group(100 mg·kg~(-1)), and metformin group(140 mg·kg~(-1)), with 12 mice in each group. After establishing the DN model, mice were given drugs or solvent intragastrically, once a day for consecutive 10 weeks. Body weight, daily water intake, and fasting blood glucose(FBG) were measured every two weeks. After the last dose, the glucose tolerance test was performed, and the samples of 24-hour urine, serum, and kidney tissue were collected. The levels of 24 hours urinary total protein(24 h-UTP), serum creatinine(Scr), blood urea nitrogen(BUN), triglyceride(TG), total cholesterol(TC), low density lipoprotein cholesterol(LDL-C), and high density lipoprotein cholesterol(HDL-C) were detected by biochemical tests. Periodic acid-schiff(PAS) staining was used to observe the pathological changes in the kidney tissue. The protein expressions of α-smooth muscle actin(α-SMA), vimentin, and advanced glycation end products(AGEs) in kidneys were detected by immunohistochemical staining. The activities of superoxide dismutase(SOD), catalase(CAT), glutathione peroxidase(GSH-PX), and the level of malondialdehyde(MDA) in kidneys were detected by using a corresponding detection kit. Enzyme-linked immunosorbent assay(ELISA) was used to detect the levels of AGEs, carboxymethyllysine(CML), and carboxyethyllysine(CEL) in serum. The protein expressions of RAGE and the phosphorylation level of JAK1 and STAT3 in kidneys were detected by Western blot. Compared with the normal group, the levels of FBG, the area under the curve of glucose(AUCG), water intake, kidney index, 24 h-UTP, tubular injury score, extracellular matrix deposition ratio of the renal glomerulus, the serum levels of Scr, BUN, TG, LDL-C, AGEs, CEL, and CML, the level of MDA, the protein expressions of α-SMA, vimentin, AGEs, and RAGE, and the phosphorylation level of JAK1 and STAT3 in kidney tissue were increased significantly(P&lt;0.01), while the level of HDL-C in serum and the activity of SOD, CAT, and GSH-PX in kidney tissue were decreased significantly(P&lt;0.01). Compared with the model group, the above indexes of the high-dose SAL group were reversed significantly(P&lt;0.05 or P&lt;0.01). In conclusion, this study suggests that SAL can alleviate oxidative stress and renal fibrosis by inhibiting the activation of AGEs-mediated RAGE/JAK1/STAT3 signaling axis, thus playing a potential role in the treatment of DN.

Antidiabetic effect of the mixture of Cissus polyantha and Rytigynia senegalensis in high-fat diet and streptozocin-induced diabetic rats

BackgroundIn traditional Chinese medicine (TCM) practices, many plants of the Cissus and Rytigynia genera are used to treat many diseases including diabetes mellitus.The aim of this study was to evaluate the modulating effects of the mixture of the aqueous extracts of Cissus polyantha and Rytiginia senegalensis (CPRS) on some enzymes of carbohydrate metabolism, oxidative profile, and cardiovascular parameters in diabetic rats. MethodsDiabetes was induced by a diet enriched in high-fat for 30 days associated with a single intraperitoneal injection of streptozocin (35 mg/kg). Rats with a blood glucose level greater than or equal to 200 mg/dL were selected and divided into groups. Groups 1 and 2 received distilled water. Group 3 received metformin (40 mg/kg). Groups 4 and 5 received CPRS at doses of 50 and 111 mg/kg, respectively. Glycaemia, body mass, food and water intake, insulinemia, insulin resistance and insulin secretion indices, lipid profile and cardiovascular risk indices, oxidant profile, glycogen and liver enzymes were evaluated. Histology of the pancreas and heart was performed. ResultsCPRS (50 and/or 111 mg/kg) significantly (p < 0.05 to p < 0.001) reduced water and food consumption, blood glucose, HOMA-IR, coronary risk index, cholesterol, triglyceride, LDL-c, VLDL-c, and malondialdehyde levels, as well as glucose-6-phosphatase and fructose-1,6-biphosphatase activities in diabetic animals. In contrast, CPRS (50 and/or 111 mg/kg) caused an increase (p < 0.05 to p < 0.001) in body mass, insulinemia and HDL-c levels, reduced glutathione and hepatic glycogen. HOMA-β, insulin distribution, atherogenic and cardioprotective indices as well as superoxide dismutase, catalase, glucokinase, and glucose-6-phosphate dehydrogenase activities were also increased after CPRS administration. CPRS regenerated pancreatic islet β cells and decreased leukocyte infiltration in cardiomyocytes of diseased animals. ConclusionCPRS has hypoglycemic, antidyslipidemic, and antioxidant effects, thus validating its use in traditional medicine in the treatment of diabetes mellitus and its complications.

Bezafibrate alleviates diabetes-induced spermatogenesis dysfunction by inhibiting inflammation and oxidative stress

The metabolic disorders caused by diabetes can lead to various complications, including male spermatogenesis dysfunction. Exploring effective therapeutics that attenuate diabetes mellitus (DM)-induced male subfertility is of great importance. Pharmaceuticals targeting PPARα activation such as bezafibrate have been regarded as an important strategy for patients with diabetes. In this study, we use streptozocin (STZ) injection to establish a type 1 DM mice model and use bezafibrate to treat DM mice and evaluate the effects of bezafibrate on the spermatogenic function of the DM male mice. Bezafibrate treatment exhibited protective effects on DM-induced spermatogenesis deficiency, as reflected by increased testis weight, improved histological morphology of testis, elevated sperm parameters, increased serum testosterone concentration as well as increased mRNA levels of steroidogenesis enzymes. Meanwhile, testicular cell apoptosis, inflammation accumulation and oxidative stress status were also shown to be alleviated by bezafibrate compared with the DM group. In vivo and in vitro studies, PPARα specific inhibitor and PPARα knockout mice were further used to investigate the role of PPARα in the protective effects of bezafibrate on DM-induced spermatogenesis dysfunction. Our results indicated that the protection of bezafibrate on DM-induced spermatogenesis deficiency was abrogated by PPARα inhibition or deletion. Our study suggested that bezafibrate administration could ameliorate DM-induced spermatogenesis dysfunction and may represent a novel practical strategy for male infertility.

Mechanism of ultrafiltration extract of Angelicae Sinensis Radix and Hedysari Radix regulates HIF-1α signaling pathway mediated by renal hypoxia to ameliorate renal fibrosis in DKD rats

This study explored the mechanism of the ultrafiltration extract of Angelicae Sinensis Radix and Hedysari Radix in ameliorating renal fibrosis in the rat model of diabetic kidney disease(DKD) based on the expression of hypoxia-inducible factor-1α(HIF-1α)/vascular endothelial growth factor(VEGF) and HIF-1α/platelet-derived growth factor(PDGF)/platelet-derived growth factor receptor(PDGFR) signaling pathways in the DKD rats. After 1 week of adaptive feeding, 50 male SPF-grade Wistar rats were randomized into a blank group(n=7) and a modeling group. After 24 h of fasting, the rats in the modeling group were subjected to intraperitoneal injection of streptozocin and fed with a high-sugar and high-fat diet to establish a DKD model. After modeling, the rats were randomly assigned into model(n=7), low-dose ultrafiltration extract(n=7), medium-dose ultrafiltration extract(n=7), irbesartan(n=8), and high-dose ultrafiltration extract(n=8) groups. After intervention by corresponding drugs for 12 weeks, the general conditions of the rats were observed. The body weights and blood glucose levels of the rats were measured weekly, and the 24 h urinary protein(24hUP) was measured at the 6th and 12th weeks of drug administration. After the last drug administration, the renal function indicators were determined. Masson staining was employed to observe the pathological changes of the renal tissue. The expression of prolyl hydroxylase domain 2(PHD2) and HIF-1α in the renal tissue was detected by immunohistochemistry(IHC). Real-time qPCR was employed to determine the mRNA levels of PHD2, VEGF, PDGF, and PDGFR in the renal tissue. Western blot was employed to determine the protein levels of HIF-1α, VEGF, PDGF, and PDGFR in the renal tissue. The results showed that compared with the model group, drug administration lowered the levels of glycosylated serum protein(GSP), aerum creatinine(Scr), and blood urea nitrogen(BUN) in a dose-dependent manner(P&lt;0.05 or P&lt;0.01) and mitigated the pathological changes in the renal tissue. Furthermore, drug administration up-regulated mRNA level of PHD2(P&lt;0.05 or P&lt;0.01), down-regulated the mRNA levels of VEGF, PDGF, and PDGFR(P&lt;0.05 or P&lt;0.01) and the protein levels of HIF-1α, VEGF, PDGF, and PDGFR(P&lt;0.01) in the renal tissue, and increased the rate of PHD2-positive cells(P&lt;0.01). In conclusion, the ultrafiltration extract of Angelicae Sinensis Radix and Hedysari Radix effectively alleviated the renal fibrosis in DKD rats by inhibiting the expression of key proteins in the HIF-1α signaling pathway mediated by renal hypoxia and reducing extracellular matrix(ECM) deposition.

Comparison of in vivo pharmacokinetics of twelve constituents in Qihe Fenqing Yin in normal rats and diabetic rats

This paper aims to study the pharmacokinetic differences of twelve effective constituents(succinic acid, neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, protocatechuic aldehyde, caffeic acid, 5-O-ferulogeninic acid, p-coumaric acid, nuciferine, quercetin, oleanolic acid, and ursolic acid) in Qihe Fenqing Yin in normal and diabetic rats. The diabetic rat model was established by a high-fat diet combined with intraperitoneal injection of streptozocin. A UHPLC-QTRAP-MS/MS method was established for the simultaneous determination of 12 constituents in the plasma of normal rats and model rats after a single intragastric administration of Qihe Fenqing Yin. The results show that the established analytical method has a good linear relationship with the 12 components, and the specificity, accuracy, precision, and stability meet the requirements. The computational pharmacokinetic parameters are fitted by DAS 3.2.8 software, and the results show that the half-life time(t_(1/2)) of the other nine components in the model group was longer than that in the normal group except for caffeic acid, 5-O-ferulogeninic acid, and oleanolic acid. The area under curve(AUC_(0-t)) of cryptochlorogenic acid, p-coumaric acid, ursolic acid, and oleanolic acid increases compared with the normal group. Meanwhile, mean residence time(MRT) delays. The &quot;double peaks&quot; of quercetin and nuciferine in the normal group are not observed in the model group, suggesting that the pharmacokinetic parameters of the drugs in the disease state are significantly different.

Mechanism underlying the anti-diabetic potential of bee venom as compared to bone marrow mesenchymal stem cells in the diabetic rat tongue.

Diabetes mellitus (DM) is a critical chronic metabolic disease. Several treatment modalities are currently under investigation. Both bee venom (BV) and bone marrow mesenchymal stem cells (BMSCs) can possibly offer an approach for treating type I diabetes. The aim of the present study was to investigate the mechanism underlying the anti-diabetic effect of BV as compared to BMSCs on the tongue mucosa of diabetic rats. A total of 52 male albino rats were used in the current study. The rats were randomly assigned into 4 groups: group 1 (control); group 2 (streptozocin (STZ)); group 3 (BV-treated); and group 4 (BMSC-treated). Diabetes mellitus was induced via an intraperitoneal (IP) injection of STZ in the rats from groups 2, 3 and 4. Following the diagnosis of DM, the rats in group 3 were injected with a daily dose of 0.5 mg/kg of BV, while the rats in group 4 were treated with a single injection of BMSCs. All rats were euthanized after 4 weeks, and their tongues were dissected and divided into halves. The right halves of the tongues were utilized for the histological examination, followed by morphometric analysis. In contrast, the left halves were used to detect the local gene expression of transforming growth factor beta 1 (TGF-β1) and vascular endothelial growth factor (VEGF). Group 2 revealed marked disruption in the morphology of the fungiform and filiform papillae, and atrophic epithelial changes in both dorsal and ventral surface epithelium as compared to other groups. Group 4 showed a significantly larger number of taste buds, and a higher gene expression of TGF-β1 and VEGF as compared to groups 2 and 3. Additionally, BV and BMSCs effectively increased the thickness of dorsal and ventral surface epithelium as compared to group 2. Treatment with BMSCs was associated with significant improvement in the morphology and number of lingual epithelial cells and taste buds in the tongues of diabetic rats as compared to BV-treated rats, which was due to the local upregulation of TGF-β1 and VEGF gene expression.

Effect of aminoguanidine on plasminogen activator inhibitor-1 and receptor of advanced glycation endproduct in the liver of streptozotocin-induced diabetic rats

Objectives: Advanced glycation end products (AGEs) play an important role in the development and progression of diabetic complications. The receptor for AGE (RAGE) is the ligand-binding site of AGE that initiates and accelerates the atherosclerotic process. Plasminogen activator inhibitor-1 (PAI-1) is a prothrombotic factor that has been proposed as a biological marker for prognostic assessment, monitoring of microvascular and macrovascular complications in diabetes. The purpose of this study is to investigate the effects of aminoguanidine on RAGE and PAI-1 expression levels in the liver of streptozotocin-induced diabetic rats.&#x0D; Methods: Diabetes was induced in rats by intraperitoneal injection of streptozocin (STZ, 50 mg/kg). On day 3, diabetic rats were administered 50, 100, and 200 mg/kg/day of aminoguanidine. The expression of PAI-1 and RAGE in the liver tissue was evaluated using real-time PCR.&#x0D; Results: PAI-1 and RAGE gene expression levels were higher in the liver of the diabetic rats compared to the control group. Aminoguanidine at 50, 100, and 200 mg/kg decreased PAI-1 and RAGE gene expression in the liver (p&lt;0.001 at all doses). However, these genes were downregulated only at a dose of 200 mg/kg in healthy rats (p&lt;0.0001). In addition, hepatic AGE protein levels were significantly decreased following treatment of the diabetic rats with aminoguanidine (p&lt;0.001). There was also a significant correlation between AGE protein concentration and the expression of PAI-1 and RAGE.&#x0D; Conclusion: In summary, the data of the present study suggest that aminoguanidine reduced the expression of PAI-1 and RAGE in the liver of the diabetic rats.

Carvacrol improves blood lipid and glucose in rats with type 2 diabetes mellitus by regulating short-chain fatty acids and the GPR41/43 pathway.

Type 2 diabetes mellitus (T2DM) is characterized by hyperglycemia and dyslipidemia. Carvacrol (CAR) has demonstrated the potential to mitigate dyslipidemia. This study aims to investigate whether CAR can modulate blood glucose and lipid levels in a T2DM rat model by regulating short-chain fatty acids (SCFAs) and the GPR41/43 pathway. The T2DM rat model was induced by a high-fat diet combined with low-dose streptozocin injection and treated with oral CAR and/or mixed antibiotics. Fasting blood glucose, oral glucose tolerance, and insulin tolerance tests were assessed. Serum lipid parameters, hepatic and renal function indicators, tissue morphology, and SCFAs were measured. In vitro, high glucose (HG)-induced IEC-6 cells were treated with CAR, and optimal CAR concentration was determined. HG-induced IEC-6 cells were treated with SCFAs or/and GPR41/43 agonists. CAR significantly reduced blood lipid and glucose levels, improved tissue damage, and increased SCFA levels in feces and GPR41/43 expression in colonic tissues of T2DM rats. CAR also attenuated HG-induced apoptosis of IEC-6 cells and enhanced GPR41/43 expression. Overall, these findings suggest that CAR alleviates blood lipid and glucose abnormalities in T2DM rats by modulating SCFAs and the GPR41/43 pathway.

DEVELOPMENT OF PATHOLOGICAL CHANGES IN THE ORAL CAVITY ORGANS OF ANIMALS UNDER CONDITIONS OF POLYNEUROPATHIES OF DIFFERENT GENESIS

The aim of our research is to study the effect of polyneuropathy of different genesis on the development of pathological changes in the large salivary glands and periodontal tissues of animals. Methods. The study was conducted on 62 laboratory rats of both sexes. Toxic polyneuropathy was induced by paclitaxel injection, experimental type 1 diabetes mellitus was modeled by streptozocin injection, and alcoholic polyneuropathy was induced by chronic administration of increasing concentrations of ethanol. The development of polyneuropathy was confirmed by a change in the the pain sensitivity threshold (PST) using the Randall-Selitto tensoalgometric method. In the homogenate of oral cavity organs, total proteolytic and total antitryptic activity, catalase activity, content of TBARS, average mass molecules, oxidatively modified proteins, fucose and glycosaminoglycans (GAG), and amylase activity were determined. The level of total, protein-bound and non-protein sulfhydryl groups, activity of superoxide dismutase, glutathione peroxidase, glutathione transferase, glutathione reductase; content of reduced and oxidized glutathione, diene conjugates and Schiff bases were determined in blood serum. Results. We established the increasing of PST in animals that were simulated neuropathies of different genesis. All three types of polyneuropathies are accompanied by the development of carbonyl-oxidative stress in the soft tissues of the periodontium and large salivary glands of rats, which is evidenced by a probable increase in the content of oxidatively modified proteins and the content of TBARS, as well as average mass molecules compared to these indicators in intact animals . Under the conditions of modeling all three polyneuropathies, the protein-synthetic activity in the large salivary glands is suppressed, as evidenced by a decrease in the activity of α-amylase. Under conditions of experimental diabetic and toxic neuropathy in the salivary glands of animals, changes in the proteinase-inhibitor balance of the compensatory type are observed. We found that polyneuropathies of different genesis cause increased catabolism of biopolymers of the extracellular matrix of the periodontal connective tissue of rats, which confirms the increase in the content of GAG and fucose compared to these indicators in control animals. Conclusions. Under conditions of diabetic, toxic and alcoholic neuropathy, the amylolytic activity of the large salivary glands of animals is suppressed, the balance of the pro- and antioxidant system changes. When modeling peripheral polyneuropathy in animals by administration of paclitaxel, streptozocin, and ethanol, the development of periodontal syndrome is observed, the leading pathogenetic mechanisms of which are increased catabolism of connective tissue glycoconjugates and the development of oxidative stress and proteinase-inhibitor imbalance.

Effect of Coadministration of Hydroalcoholic Extracts of Aegle marmelos Leaves and Tamarindus indica Seeds on Streptozocin-Nicotinamide Induced Type- 2 Diabetic Rat Model

It is difficult for doctors to control hyperglycemia in type 2 diabetes patients without having an effect that is too detrimental to the patient, despite the advancements that have been made in diabetes medications. Because of their adaptability and capacity to lower blood sugar with very few unintended side effects, herbal preparations are quickly gaining in popularity worldwide. In this study, hydroalcoholic extracts of Tamarindus indica seeds and Aegle marmelos leaves were tested to determine what kind of effect they had on a model of diabetes carried out on rats. For the purpose of this investigation, 54 male Sprague Dawley (SD) rats were used as participants. Group I comprised of six people who did not have diabetes and were considered to be in good health. Intraperitoneal injections of streptozocin (55 mg/kg) and nicotinamide (NAD) (120 mg/kg) were used to induce diabetes in the remaining animals (n = 48). Following that, we divided them up into a total of eight distinct categories. Animals in groups IV and V were given AM at doses of 25 and 50 mg/kg/day, animals in groups VI and VII were given TI at doses of 25 and 50 mg/kg/day, animals in groups VIII and IX were given a combination of the two extracts (AM25+TI25 &amp; AM50+TI50), while diabetic animals were used as controls in group II. A positive control consisting of metformin given at a dose of 200 mg/kg per day was utilized in group III. When compared to the diabetic control group, the fasting blood glucose levels and the area under the curve (AUC) of the oral glucose tolerance test were lower in all treatment groups. When compared to the metformin groups, the performance of the extract combination groups was considerably superior (p 0.01). Additionally, as compared to the diabetic control group, all of the treatment groups had significantly reduced levels of MDA and hepatic G-6-Pase activity (p 0.001). In terms of effectiveness, the combination group performed much better than the metformin group despite the fact that all pharmacological groups showed significant increases in body weight, relative liver weight, HDL level, and liver glycogen content in comparison to the diabetic controls. (p &lt;05). When compared to the diabetic control group, all therapy groups showed an increase in G-6PD activity (p 0.001), catalase levels (p 0.001), and glutathione (GSH) levels (p 0.05). In STZ-induced type 2 diabetic rats, a combination of extracts (AM50+T150) demonstrated the best improvement after 30 days of therapy when compared to metformin and hydroalcoholic extracts (AM and TI) alone. This was the case even when both treatments were administered separately. There was no difference in the circumstances no matter which extracts were utilized.

The onset of adenosine monophosphate-activated protein kinase activity on orthodontic tooth movement in rats with type 2 diabetes.

Adenosine monophosphate-activated protein kinase (AMPK) plays pivotal roles in metabolic diseases including type 2 diabetes. However, the specific role of AMPK for orthodontic tooth movement in type 2 diabetes is unclear. In this study, a diabetic rat model was established through dietary manipulation and streptozocin injection. Examinations were conducted to select qualified type 2 diabetic rats. Then, an orthodontic device was applied to these rats for 0, 3, 7, or 14 days. The distance of orthodontic tooth movement and parameters of alveolar bone were analyzed by micro-computed tomography. Periodontal osteoclastic activity, inflammatory status, and AMPK activity were measured via histological analyses. Next, we repeated the establishment of diabetic rats to investigate whether change of AMPK activity was associated with orthodontic tooth movement under type 2 diabetes. The results showed that diabetic rats exhibited an exacerbated alveolar bone resorption, overactive inflammation, and decreased periodontal AMPK activity during orthodontic tooth movement. Injection of the AMPK agonist alleviated type 2 diabetes-induced periodontal inflammation and alveolar bone resorption, thus normalizing distance of orthodontic tooth movement. Our study indicates that type 2 diabetes decreases periodontal AMPK activity, leading to excessive inflammation elevating osteoclast formation and alveolar bone resorption, which could be reversed by AMPK activation.