Streptozotocin-induced Diabetic Rat Model Research Articles

Co-Delivery of Dragon’s Blood and Alkanna tinctoria Extracts Using Electrospun Nanofibers: In Vitro and In Vivo Wound Healing Evaluation in Diabetic Rat Model

The increasing prevalence of diabetic wounds presents a significant challenge due to the difficulty of natural healing and various obstacles. Dragon’s blood (DB) and Alkanna tinctoria (AT) are well recognized for their potent healing abilities, which include potent antibacterial and anti-inflammatory activities. In this study, electrospun nanofibers (NFs) based on polyvinyl pyrrolidone (PVP) were co-loaded with both DB and AT, aiming to magnify their efficacy as wound-dressing applications for diabetic wound healing. The evaluation of these NFs as wound dressings was conducted using a streptozotocin-induced diabetic rat model. Electrospun NFs were prepared using the electrospinning of the PVP polymer, resulting in nanofibers with consistent, smooth surfaces. The loading capacity (LC) of AT and DB into NFs was 64.1 and 70.4 µg/mg, respectively, while in the co-loaded NFs, LC was 49.6 for AT and 57.2 µg/mg for DB. In addition, X-ray diffraction (XRD) revealed that DB and AT were amorphously dispersed within the NFs. Top of Form The loaded NFs showed a dissolution time of 30 s in PBS (pH 7.4), which facilitated the release of AT and DB (25–38% after 10 min), followed by a complete release achieved after 180 min. The antibacterial evaluation demonstrated that the DB-AT mixture had potent activity against Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus). Along with that, the DB-AT NFs showed effective growth inhibition for both P. aeruginosa and S. aureus compared to the control NFs. Moreover, wound healing was evaluated in vivo in diabetic Wistar rats over 14 days. The results revealed that the DB-AT NFs improved wound healing within 14 days significantly compared to the other groups. These results highlight the potential application of the developed DB-AT NFs in wound healing management, particularly in diabetic wounds.

Investigation of diabetes-related molecular changes in embryo-endometrium crosstalk

The primary aim of this study was to explore the impact of diabetes on matrix metalloproteases and tissue inhibitors, crucial factors for successful implantation, and to elucidate the molecular mechanisms that undergo changes in the endometrium and the embryo during diabetic pregnancies. In this investigation, we established a streptozotocin-induced diabetic pregnant rat model. Microarray analysis followed by RT-PCR was utilized to identify gene regions exhibiting expression alterations. Subsequently, we assessed the effects of MMPs and tissue inhibitors using ELISA and immunohistochemistry techniques, in addition to analyzing changes at the genetic level. Diabetes led to the upregulation of MMP3, MMP9, and MMP20 on the 6.5th day of pregnancy, while causing the downregulation of MMP3, MMP9, and MMP11 on the 8.5th day of pregnancy. TIMP1 expression was downregulated on the 8.5th day compared to the control group. No statistically significant differences were observed between the groups regarding other TIMP expressions. KEGG pathway analysis revealed that diabetes induced alterations in the expression of genes associated with certain microRNAs, as well as signaling pathways such as cAMP, calcium, BMP, p53, MAPK, PI3K-Akt, Jak-STAT, Hippo, Wnt, and TNF. Additionally, gene ontology analysis unveiled changes in membrane structures, extracellular matrix, signaling pathways, ion binding, protein binding, cell adhesion molecule binding, and receptor-ligand activity. This study serves as a valuable guide for investigating the mechanisms responsible for complications in diabetic pregnancies. By revealing the early-stage effects of diabetes, it offers insight into the development of new diagnostic and treatment approaches, ultimately contributing to improved patient care.

Glucotoxicity is mediated by cytoplasmic distribution of RAP1 in pancreatic β-cells

Diabetes mellitus (DM) is a group of chronic metabolic disorders characterized by persistent hyperglycemia. In our study, we analyzed the level and location of RAP1 changes in the development of β-cell dysfunction induced by glucotoxicity. We employed three pancreatic β-cell lines, namely INS-1, 1.2B4, and NIT-1, as well as a streptozotocin-induced diabetes rat model. We demonstrate that after high glucose treatment, RAP1 is increased, probably through induction by AKT, allowing RAP1 to shuttle from the nucleus to the cytoplasm and activate NF-κB signaling. Furthermore, non-enzymatic post-translational modifications of RAP1, such as advanced glycation end products and carbonylation may affect the function of RAP1, such as activation of the NF-κB signaling. Taken together, we showed that RAP1 is a new player in the mechanism of glucotoxicity in pancreatic β-cells.

Assessment of Cyperus articulatus for Antidiabetic Effects in a Streptozotocin-Induced Diabetic Rat Model

Assessment of Cyperus articulatus for Antidiabetic Effects in a Streptozotocin-Induced Diabetic Rat Model

Hepatic and renal effects of oral stingless bee honey in a streptozotocin-induced diabetic rat model.

Diabetes is known damage the liver and kidney, leading to hepatic dysfunction and kidney failure. Honey is believed to help in lowering the blood glucose levels of diabetic patients and reducing diabetic complications. However, the effect of stingless bee honey (SBH) administration in relieving liver and kidney damage in diabetes has not been well-studied. To investigate the effect of SBH administration on the kidney and liver of streptozotocin-induced (STZ; 55 mg/kg) diabetic Sprague Dawley rats. The rats were grouped as follows (n = 6 per group): non-diabetic (ND), untreated diabetic (UNT), metformin-treated (MET), and SBH+metformin-treated (SBME) groups. After successful diabetic induction, ND and UNT rats were given normal saline, whereas the treatment groups received SBH (2.0 g/kg and/or metformin (250 mg/kg) for 12 d. Serum biochemical parameters and histological changes using hematoxylin and eosin (H&E) and periodic acid-Schiff (PAS) staining were evaluated. On H&E and PAS staining, the ND group showed normal architecture and cellularity of Bowman's capsule and tubules, whereas the UNT and MET groups had an increased glomerular cellularity and thickened basement membrane. The SBH-treated group showed a decrease in hydropic changes and mild cellularity of the glomerulus vs the ND group based on H&E staining, but the two were similar on PAS staining. Likewise, the SBME-treated group had an increase in cellularity of the glomerulus on H&E staining, but it was comparable to the SBH and ND groups on PAS staining. UNT diabetic rats had tubular hydropic tubules, which were smaller than other groups. Reduced fatty vacuole formation and dilated blood sinusoids in liver tissue were seen in the SBH group. Conversely, the UNT group had high glucose levels, which subsequently increased MDA levels, ultimately leading to liver damage. SBH treatment reduced this damage, as evidenced by having the lowest fasting glucose, serum alanine transaminase, aspartate transaminase, and alkaline phosphatase levels compared to other groups, although the levels of liver enzymes were not statistically significant. The cellularity of the Bowman's capsule, as well as histological alteration of kidney tubules, glomerular membranes, and liver tissues in diabetic rats after oral SBH resembled those of ND rats. Therefore, SBH exhibited a protective hepatorenal effect in a diabetic rat model.

Ocimum gratissimum L. leaf flavonoid-rich extracts reduced the expression of p53 and VCAM in streptozotocin-induced cardiomyopathy rats

BackgroundThis study aimed to investigate the potential cardioprotective effects of flavonoid-rich extracts from Ocimum gratissimum leaves in a streptozotocin-induced diabetic rat model by assessing redox stress biomarkers, ATPase activities, gene expression levels, enzyme activities, and histopathological changes. MethodsDiabetic rats were administered low (LDOGFL) and high (HDOGFL) doses of O. gratissimum leaf flavonoid-rich extracts, metformin (MET), or served as diabetic (DC) and normal (NC) controls for twenty-one days. Various cardiac parameters were evaluated, including redox stress biomarkers, ATPase activities, relative gene expression of p53 and VCAM, phosphatase activities, transaminase activities, serum creatine kinase-MB (CKMB) activities, cardiac troponin levels, and natriuretic peptide levels. Additionally, heart histoarchitecture was also examined using hematoxylin and eosin (H&E) staining. ResultsFlavonoid-rich extracts of O. gratissimum significantly (p < 0.05) mitigated redox stress by decreasing malondialdehyde (MDA) levels and increasing reduced glutathione (GSH), glutathione-S-transferase (GST), catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) activities in diabetic treated rats. The extracts also notably (p < 0.05) improved ATPase activities and significantly (p < 0.05) modulated the relative gene expression of p53 and VCAM in diabetic treated rats. Furthermore, diabetic rat administered flavonoid-rich extracts markedly (p < 0.05) attenuated phosphatase activities, transaminase activities, CKMB activities, cardiac troponin levels, and natriuretic peptide levels. Histopathological examination of the diabetic rats revealed improved cardiac histoarchitecture in extract-treated groups compared to diabetic controls. ConclusionThese findings suggest that O. gratissimum leaf flavonoid-rich extracts confer cardioprotective effects in STZ-induced diabetic rats by ameliorating redox imbalance, modulating gene expression, regulating enzyme activities, and preserving cardiac histoarchitecture. These results highlight the potential therapeutic application of O. gratissimum flavonoids in managing diabetes-induced cardiomyopathy.

Hypoglycemic and hypolipidemic activity of a catfish oil and Andrographis paniculata herb extract combination in diabetic rat model

The single use of natural ingredients for the treatment of diabetes mellitus is considered less optimal compared to the combination of several ingredients which is expected to produce a synergistic effect. Therefore, this study aimed to investigate the combined effect of catfish oil (CFO) and Andrographis paniculata ethanolic extract (APE) in reducing blood glucose levels and hyperlipidemia in a diabetic rat model. A total of 30 male Wistar rats were used while diabetes was induced using 50 mg/kg streptozotocin. The rats were randomly divided into six groups consisting of the control, diabetes, and drug control group treated with metformin 120 mg/kg; as well as treatments I, II, and III given CFO 1000 mg/kg, CFO 1000 mg/kg + APE 200 mg/kg, and CFO 1000 mg/kg + APE 400 mg/ kg, respectively. The test was carried out for 28 days, then on the 29th day, all the test animals were examined for observation of blood glucose levels and lipid profiles. In the fourth week of testing, all groups showed a significantly different blood glucose profile compared to the diabetes control group with p&lt;0.05. The combined administration of 1000 mg/kg CFO and 400 mg/kg APE showed a better reduction in blood glucose compared to the single dose of CFO (p&lt;0.05). Furthermore, the lipid profiles showed a significant reduction compared with the diabetes control (p&lt;0.05). Except for LDL values, the combination of both doses of CFO+APE showed a better reduction in lipid profile compared to the single CFO. A single dose of CFO and a combination dose of APE provided a beneficial effect by inhibiting the increase in blood glucose levels and lipid profiles in a streptozotocin-induced diabetic rat model. Based on the results, the combined dose of 1000 mg/kg CFO+400 mg APE produced a better effect on most of the blood biochemical parameters than the single administration of CFO

Cardioprotective and Hypolipidemic Effect of Cardamom Oil-Loaded Lipid Carrier Nanoparticles in a Rat Model of Streptozotocin-Induced Diabetes

Background: Diabetic cardiomyopathy (DCM) is a serious complication of poorly managed diabetes. Inflammation, hyperglycemia, oxidative stress, hyperlipidemia, and other factors all play a role in DCM pathogenesis. Objective: To investigate the cardioprotective effects of cardamom oil-loaded lipid carrier nanoparticles (CEO-LC NPs) on streptozotocin (STZ)-induced diabetes in rats. Methods: Twenty-four male rats were randomly divided into four groups of six each. STZ (50 mg/kg) caused diabetes in all groups but the negative control. The diabetic control group (G1) received a normal saline solution. For 28 days, group G2 received CEO-LC NPs (600 mg/kg), group G3 received empagliflozin (10 mg/kg), and group G4 (no diabetes) received normal saline as a negative control. On day 29, blood samples were taken to determine blood glucose, cholesterol, LDL, HDL, and triglyceride levels, as well as oxidative stress markers. Additionally, atherogenic indices were calculated. Heart tissue was sent for histopathological examination. Results: In diabetic rats treated with CEO-LC NPs, serum glucose, cholesterol, LDL, and triglyceride levels were significantly reduced, while HDL levels increased. The CEO-LC NP treatment also reduced oxidative stress by increasing total antioxidant capacity while decreasing malondialdehyde (MDA). Furthermore, diabetic rats treated with CEO-LC NP had significantly lower AIP, CRI-I, and CRI-II ratios. Conclusions: CEO-LC NPs improve cardioprotection in STZ-induced diabetic rats by lowering plasma lipid levels and oxidative stress.

Omentum Extracellular Matrix-Silk Fibroin Hydroscaffold Promotes Wound Healing through Vascularization and Tissue Remodeling in the Diabetic Rat Model.

Nonhealing diabetic wounds are often associated with significant mortality and cause economic and clinical burdens to the healthcare system. Herein, a biomimetic hydroscaffold is developed using omentum tissue-derived decellularized-extracellular matrix (dECM) and silk fibroin (SF) proteins that associate the behavior of a collagenous fibrous scaffold and a hydrogel to reproduce all aspects of the provisional skin tissue matrix. The chemical cross-linker-free in situ gelation property of the two types of SF proteins from Bombyx mori and Antheraea assamensis ensures the adherence of dECM with surrounding tissue on the wound bed, circumventing further suturing. The physicochemical and mechanical properties of the composite hydroscaffold (SF-dECM) were thoroughly evaluated. The hydroscaffolds were found to support the growth and proliferation of human dermal fibroblasts and influence the angiogenic potential of endothelial cells under in vitro conditions. Furthermore, the healing efficacy of the composites was evaluated by generating full-thickness wounds on a streptozotocin-induced diabetic rat model. The presence of dECM components in the composite facilitated the rate of wound closure, granulation tissue formation, and re-epithelialization by providing intrinsic cues to advance the inflammatory stage and stimulating angiogenesis. Collectively, as an off-the-shelf wound dressing requiring only a single topical administration, the SF-dECM hydroscaffold is a promising, cost-effective dressing for the management of chronic diabetic wounds.

Multifunctional alginate/polydeoxyribonucleotide hydrogels for promoting diabetic wound healing

A multifunctional alginate/PDRN hydrogel system by ionic crosslinking and the Schiff base reaction between oxidized alginate (OA) and PDRN was developed in the present study. Biocompatibility assessment of the PDRN-loaded OA hydrogels showed a significant enhancement in cell viability in human dermal fibroblast (HDF) cells. In addition, hydrogels showed migratory, anti-inflammatory, intracellular reactive oxygen species scavenging, and anti-apoptotic activities. In vivo studies using a streptozotocin-induced diabetic Wister rat model indicated that OA-4PDRN had the highest percentage of wound closure (96.1 ± 2.6 %) at day 14 compared to the control (79.0 ± 2.3 %) group. This was accompanied by up-regulation of vascular endothelial growth factor (VEGF), interleukin-10 (IL-10), and transforming growth factor-beta (TGF-β) accompanied by down-regulation of pro-inflammatory markers (IL-6, IL-1β). Following histopathological observations, PDRN-loaded OA hydrogel ensured tissue safety and induced wound healing with granular tissue formation, collagen deposition, re-epithelialization, and regeneration of blood vessels and hair follicles. The downregulation of inflammatory cytokines (CD68) and expression of angiogenesis-related cytokines (CD31) in wound sites revealed the suppression of inflammation and increased angiogenesis, ensuring skin tissue regeneration in diabetic wound healing. In conclusion, the findings suggest that PDRN-loaded OA hydrogel has enormous therapeutic potential as a diabetic wound dressing.

Ngu-Vi-Tieu-Khat decoction, a Vietnamese traditional medicine, possesses hypoglycemic and hypolipidemic effects on streptozotocin-induced type-2 diabetic rat model

This study aims to assess the hypoglycemic effects of Ngu-Vi-Tieu-Khat (NVTK) decoction, a traditional Vietnamese medicine, in a rat model of type-2 diabetes. The NVTK decoction was prepared using the maceration method and tested for its hypoglycemic effects by measuring blood glucose levels, insulin resistance indicators, and pancreatic mass. The results showed that NVTK decoction improved diabetes symptoms, increased insulin levels, reduced insulin resistance, restored pancreatic mass, and decreased total cholesterol (TC), triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C) while increasing high-density lipoprotein cholesterol (HDL-C). The hypoglycemic effects of NVTK were comparable to those of gliclazide at a dose of 10 mg/kg. In conclusion, NVTK decoction possesses hypoglycemic properties and could be explored as a potential traditional medicine for treating type-2 diabetes in humans.

Evaluation of the therapeutic potentials of extract fractions of Vernonia calvoana on streptozotocin-induced diabetic rats: approach through in silico, in vitro and in vivo studies

BackgroundDiabetes is a serious metabolic disorder and many medicinal plants are used in traditional medicine to manage it. This study aimed to evaluate the therapeutic effects of Vernonia calvoana (V. calvoana) extract fractions on streptozotocin-induced diabetic rat models. In this study, we first investigated the binding affinity of ligands from extracts of V. calvoana crystal structure proteins using a molecular docking approach. Furthermore, the in silico predictions were validated by in vitro and in vivo biochemical evaluations to ascertain the efficacy of these extract fractions. The in vitro antioxidant activity of the fractions was evaluated using DPPH, FRAP, SOD, and LPx scavenging. For biological activity, extract fractions of V. calvoana and metformin (400 mg and 500 mg/kg body weight, respectively) were administered to diabetic rats for 21 days after induction and confirmation of diabetes.ResultsThe radical scavenger activities of the fractions showed a good dose-dependent reaction activity. A significant reduction in hyperglycemia, hyperlipidemia, nephrotoxicity, and hepatotoxicity was observed in all experimental treated groups. Improved hematological and histopathological changes were also observed.ConclusionThe In silico analyses revealed that all the compounds from extract fractions of V. calvoana have varying binding affinity for PFK and lipoprotein lipase, with some showing higher affinity than the standard drug, further validating the biological activity of the plant. The results of this study indicated that V. calvoana extracts might have potential value in treating complications arising from diabetes mellitus.

Melatonin downregulates the increased hepatic alpha-fetoprotein expression and restores pancreatic beta cells in a streptozotocin-induced diabetic rat model: a clinical, biochemical, immunohistochemical, and descriptive histopathological study.

Diabetes mellitus (DM) is a chronic metabolic disorder. Hepatopathy is one of the serious effects of DM Melatonin (MT) is a potent endogenous antioxidant that can control insulin output. However, little information is available about the potential association between melatonin and hepatic alpha-fetoprotein expression in diabetes. This study was conducted to assess the influence of MT on diabetes-related hepatic injuries and to determine how β-cells of the pancreas in diabetic rats respond to MT administration. Forty rats were assigned to four groups at random (ten animals per group). Group I served as a normal control group. Group II was induced with DM, and a single dose of freshly prepared streptozotocin (45 mg/kg body weight) was intraperitoneally injected. In Group III, rats received 10 mg/kg/day of intraperitoneal melatonin (IP MT) intraperitoneally over a period of 4 weeks. In Group IV (DM + MT), following the induction of diabetes, rats received MT (the same as in Group III). Fasting blood sugar, glycosylated hemoglobin (HbA1c), and serum insulin levels were assessed at the end of the experimental period. Serum liver function tests were performed. The pancreas and liver were examined histopathologically and immunohistochemically for insulin and alpha-fetoprotein (AFP) antibodies, respectively. MT was found to significantly modulate the raised blood glucose, HbA1c, and insulin levels induced by diabetes, as well as the decreased alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Furthermore, MT attenuated diabetic degenerative changes in the pancreas and the hepatic histological structure, increased the β-cell percentage area, and decreased AFP expression in the liver tissue. It attenuated diabetes-induced hepatic injury by restoring pancreatic β-cells; its antioxidant effect also reduced hepatocyte injury. Collectively, the present study confirmed the potential benefits of MT in downregulating the increased hepatic alpha-fetoprotein expression and in restoring pancreatic β-cells in a streptozotocin-induced diabetic rat model, suggesting its promising role in the treatment of diabetes.

Nitro-oleic acid ameliorates erectile dysfunction in a streptozotocin-induced rat model of diabetes by inhibiting oxidative stress and apoptosis and activating the NO/cGMP pathway.

The major vascular complications associated with diabetes make the management of diabetic mellitus erectile dysfunction (DMED) a challenging endeavor. Notable factors contributing to DMED include oxidative stress, nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) pathway activation, and apoptosis, while nitro-oleic acid (NO2-OA) has been shown to be beneficial in treating these aspects of this condition. We, herein, investigated the effects and possible mechanisms of NO2-OA on erectile function as assessed in a streptozotocin-induced rat model of diabetes. Our results revealed that the erectile function of DMED rats was significantly impaired compared with that of the control group. However, in response to 4 weeks of NO2-OA treatment, there was an improvement in erectile function. The expression of oxidative stress-related indicators was significantly increased and the NO/cGMP pathway was impaired in the DMED group. The expression of proapoptotic factors was increased, while that of antiapoptotic factors was decreased in the DMED group. Moreover, the cell morphology in the cavernous tissue of the DMED group also changed adversely. NO2-OA treatment significantly reversed all these changes observed in the DMED group. In conclusion, NO2-OA treatment partially improved erectile function in DMED rats through mechanisms that included inhibition of oxidative stress, activation of the NO/cGMP pathway, and a reduction in apoptosis.

Coconut (Cocos nucifera L.) inflorescence sap-derived sugar restores the glucose and lipid homeostasis in streptozotocin-induced diabetic Wistar rat model

Coconut (Cocos nucifera L.) inflorescence sap-derived sugar restores the glucose and lipid homeostasis in streptozotocin-induced diabetic Wistar rat model

Antidiabetic and antioxidant effect of magnetic and noble metal nanoparticles of Clitoria ternatea

Diabetes is a chronic metabolic endocrine disorder associated with diabetic complications that result in microvascular and macrovascular complications due to oxidative stress, neurodegeneration, and peripheral cell damage. Oxidative stress is characterized by the development of reactive oxygen species (ROS) which progresses by hampering antioxidant enzyme activities. Phytomolecules from different plant sources like leaves, flowers, fruits, etc are reported to possess super-antioxidant properties. Hence these phytomolecules can be good leads in the treatment and management of diabetes. Metal nanoparticles have evolved to increase the potency, efficacy, and safety of different drug delivery systems owing to their superior physicochemical properties. This research work is designed for the synthesis of magnetic and noble metal nanoparticles by green synthesis of fresh flower aqueous extract of Clitoria ternatea. A mechanistic evaluation of the magnetic (cobalt oxide) and noble metal (gold) nanoparticles has been designed by in-vitro and in-vivo models of a streptozotocin-induced diabetes model. The cobalt oxide and gold nanoparticles showed a significant (p < 0.05) decrease in the diabetic enzyme levels (α-amylase, α-glucosidase, and xanthine oxidase). In vitro and in vivo studies of the antioxidant activity of both nanoparticles also revealed the increased potential of antioxidant activity. In-vivo studies of both nanoparticles exhibited anti-diabetic properties by significantly enhancing the level of insulin. The cholesterol profiling of both nanoparticles proved the reduction of levels of serum cholesterol, triglycerides, HDL, VLDL, LDL, and creatinine content signifying the decreasing risk of macrovascular complications associated with diabetes. However, gold nanoparticles produced a more protective effect as compared to cobalt oxide nanoparticles. The study concludes that the magnetic and gold nanoparticles conjugated with Clitoria ternatea exhibited potential anti-diabetic and antioxidant activities in a streptozotocin-induced diabetic rat model.

Accelerated Wound Healing in Diabetic Rat by miRNA-185-5p and Its Anti-Inflammatory Activity.

Addressing both inflammation and epithelialization during the treatment of diabetic foot ulcers is an important step, but current treatment options are limited. MiRNA has important prospects in the treatment of diabetic foot refractory wound ulcers. Previous studies have reported that miR-185-5p reduces hepatic glycogen production and fasting blood glucose levels. We herein hypothesized that miR-185-5p might play an important role in the field of diabetic foot wounds. MiR-185-5p in skin tissue samples from patients with diabetic ulcers and diabetic rats were measured using quantitative real-time PCR (qRT-PCR). The streptozotocin-induced diabetes rat model (male Sprague-Dawley rats) for diabetic wound healing was conducted. The therapeutic potential was observed by subcutaneous injection of miR-185-5p mimic into diabetic rat wounds. The anti-inflammation roles of miR-185-5p on human dermal fibroblast cells were analyzed. We found that miR-185-5p is significantly downregulated in diabetic skin (people with DFU and diabetic rats) compared to controls. Further, in vitro upregulation of miR-185-5p decreased the inflammatory factors (IL-6, TNF-α) and intercellular adhesion molecule 1 (ICAM-1) of human skin fibroblasts under advanced glycation end products (AGEs). Meanwhile, the increase of miR-185-5p promoted cell migration. Our results also confirmed that the topical increase of miR-185-5p decreases diabetic wound p-nuclear factor-κB (p-NF-κB), ICAM-1, IL-6, TNF-α, and CD68 expression in diabetic wounds. MiR-185-5p overexpression boosted re-epithelization and expedited wound closure of diabetic rats. MiR-185-5p accelerated wound healing of diabetic rats, reepithelization, and inhibited the inflammation of diabetic wounds in the healing process, a potentially new and valid treatment for refractory diabetic foot ulcers.

Antox Repro-protective Synergistic Role with Insulin in a Streptozotocin-Induced Diabetic Rat Model (Biochemical, Histo-morphometric and Immunohistochemical study)

Antox Repro-protective Synergistic Role with Insulin in a Streptozotocin-Induced Diabetic Rat Model (Biochemical, Histo-morphometric and Immunohistochemical study)

Intravenous injection of human umbilical cord-derived mesenchymal stem cells ameliorates not only blood glucose but also nephrotic complication of diabetic rats through autophagy-mediated anti-senescent mechanism

BackgroundDiabetic nephropathy (DN) is one of the most severe complications of diabetes mellitus, which is characterized by early occurrence of albuminuria and end-stage glomerulosclerosis. Senescence and autophagy of podocytes play an important role in DN development. Human umbilical cord-derived mesenchymal stem cells (hucMSCs) have potential in the treatment of diabetes and its complications. However, the role of hucMSCs in the treatment of DN and the underlying mechanism remain unclear.MethodsIn vivo, a streptozotocin-induced diabetic male Sprague Dawley rat model was established to determine the renoprotective effect of hucMSCs on DN by biochemical analysis, histopathology, and immunohistochemical staining of renal tissues. And the distribution of hucMSCs in various organs in rats within 168 h was analyzed. In vitro, CCK8 assay, wound healing assay, and β-galactosidase staining were conducted to detect the beneficial effects of hucMSCs on high glucose-induced rat podocytes. Real-time PCR and western blot assays were applied to explore the mechanism of action of hucMSCs.ResultsThe in vivo data revealed that hucMSCs were distributed into kidneys and significantly protected kidneys from diabetic damage. The in vitro data indicated that hucMSCs improved cell viability, wound healing, senescence of the high glucose-damaged rat podocytes through a paracrine action mode. Besides, the altered expressions of senescence-associated genes (p16, p53, and p21) and autophagy-associated genes (Beclin-1, p62, and LC3) were improved by hucMSCs. Mechanistically, hucMSCs protected high glucose-induced injury in rat podocytes by activating autophagy and attenuating senescence through the AMPK/mTOR pathway.ConclusionsIn conclusion, hucMSCs might be a promising therapeutic strategy for the clinical treatment of DN-induced renal damages.

Antagonistic Insulin Derivative Suppresses Insulin-Induced Hypoglycemia.

Insulin derivatives provide new functions that are distinctive from native insulin. We investigated insulin modifications on the C-terminal A chain with insulin receptor (IR) peptide binders and presented a full and potent IR antagonist. We prepared insulin precursors featuring a sortase A (SrtA) recognition sequence, LPETGG, at the C-terminal A chain and used a SrtA-mediated ligation method to synthesize insulin derivatives. The insulin precursor exhibits full IR agonism potency, similar to native human insulin. We explored derivatives with linear IR binding peptides attached to the insulin C-terminal A chain. One insulin derivative with an IR binder (Ins-AC-S2) can fully antagonize IR activation by insulin, as confirmed by cell-based assays. This IR antagonist suppresses insulin-induced hypoglycemia in a streptozotocin-induced diabetic rat model. This study provides a new direction toward insulin antagonist development.