Diabetic Mouse Model Research Articles

Essential role of Moringa-albumin (MA) formulation in the maintenance of complement regulatory proteins on erythrocyte (TER-119) cells in diabetic mouse models.

To evaluate the essential role of Moringa-albumin (MA) formulation in the maintenance of complement regulatory proteins through CD55 and CD59 on erythrocyte (TER-119). Streptozotocin (145 mg/kg) was used to induce diabetes mice. In diabetes mellitus (DM) model mice were treated with MA formulation for 14 days at a D1 - 500 mg/kg (M) + 620 mg/kg BW (A), D2 - 1000 mg/kg (M) + 420 mg/kg (A), and D3 - 1500 mg/kg (M) + 200 mg/kg (A). On the 15th day, the mice were dissected for the isolation of their bone marrow by the flushing method. The analysis flow cytometry was performed to find out the TER-119, CD55, and CD59 expressions. The data were statistically analysed with one-way ANOVA (ρ≤ 0.05) and Tukey test using SPSS version 16 for Windows. The effect of MA administration in D3 group have a significant effect on increasing the profile of erythrocytes (TER-119), compared to DM (ρ≤0.05) group (STZ Injection-no treatment), as well as CD59 expressed by erythrocytes. MA administration in D1 group and D3 group significantly increased the profile of CD55 expressed by erythrocytes compared to DM (ρ≤0.05). MA formulation with D3 group (1500 mg/kg (M) + 200 mg/kg (A)) was able to maintain or control complement regulatory proteins (CD55 and CD59) on red blood cells (erythrocytes/TER-119) in DM.

The Impact of Light-Dark Cycle Alteration on the Acceleration of Type 1 Diabetes in NOD Mice Model.

We aimed to evaluate the effect of light-dark cycle alteration and soft drink consumption on the acceleration of type 1 diabetes mellitus (T1DM) development among non-obese diabetic (NOD) mice model. We exposed female NOD and C57BL/6 mice from the age of 5 weeks to either adlib soft drink consumption and/or T20 light-dark cycle alteration until the development of diabetes, or the mice reached the age of 30 weeks. Each group consisted of 7-15 mice. We monitored weight, length, blood glucose level, and insulin autoantibody (IAA) levels weekly. Out of 75 NOD and 22 C57BL/6 mice, 41 NOD mice developed diabetes, and 6 mice died between 7 and 8 weeks of age. The mean time to development of T1DM among NOD control mice was 20 weeks. The time to development of T1DM was accelerated by two weeks in the NOD mice exposed to light-dark cycle alteration, hazard ratio of 2.65,95th CI (0.70, 10.04) p = 0.15). The other groups developed T1DM, similar to the control group. There was a trend toward earlier development of T1DM among NOD mice exposed to light-dark cycle alteration, but this difference was not statistically significant. Further studies are needed to confirm our findings using larger sample sizes and different animal species.

Allogenic Vertebral Body Adherent Mesenchymal Stromal Cells Promote Muscle Recovery in Diabetic Mouse Model of Limb Ischemia

Chronic limb threatening ischemia (CLTI) carries a significant risk for amputation especially in diabetic patients with poor options for revascularization. Phase I trials have demonstrated efficacy of allogeneic mesenchymal stromal cells (MSC) in treating diabetic CLTI. Vertebral bone adherent mesenchymal stromal cells (vBA-MSC) are derived from vertebral bodies of deceased organ donors which offer the distinct advantage of providing a 1,000x greater yield compared to that of living donor bone aspiration. This study describes the effects of intramuscular injection of allogenic vBA-MSC in promoting limb perfusion and muscle recovery in a diabetic CLTI mouse model. A CLTI mouse model was created through unilateral ligation of the femoral artery in male polygenic diabetic TALLYHO mice. Treated mice were injected with vBA-MSC into the gracilis muscle of the ischemic limb 7 days post ligation. Gastrocnemius or tibialis muscle was assessed post-mortem for fibrosis by collagen staining, capillary density via immunohistochemistry, and mRNA by quantitative real time PCR. Laser Doppler perfusion imaging and plantar flexion muscle testing were performed to quantify changes in limb perfusion and muscle function. Compared to vehicle control, treated mice demonstrated indicators of muscle recovery including decreased fibrosis, increased perfusion, muscle torque, and angiogenesis. PCR analysis of muscle obtained 7- and 30-days post vBA-MSC injection showed an upregulation in expression of MyoD1 (p = 0.03) and MyH3 (p = 0.008) mRNA representing muscle regeneration, VEGF-A (p = 0.002 ; p = 0.004) signifying angiogenesis as well as IL-10 (p < 0.001), T regulatory cell marker Foxp3 (p = 0.04), and M2-biased macrophage marker Mrc1 (CD206) (p = 0.02). These findings indicate human allogeneic vBA-MSC ameliorate ischemic muscle damage and rescue muscle function. These results in a murine model will enable further studies to develop potential therapies for diabetic CLTI patients.

Mitochondria-targeted NIR molecular probe for detecting viscosity of gland damage and SO2 in actual samples

Glandular damage can be caused by various factors, including disease, trauma, or other abnormalities within the organism. The viscosity of the gland is one of the important indicators to measure the degree of damage. Sulfur dioxide (SO2) is widely used as an important food additive due to its preservative and bleaching properties, but its overuse has serious negative impacts on the environment, so it is urgent to develop a simple detection method. Herein, we designed and synthesized a mitochondria-targeted near-infrared (NIR) fluorescence probe (BDC) for the detection of viscosity and SO2. BDC consisted of a donor-π-acceptor (D-π-A) structure and extended double bonds bridging rotor, which enabled sensitive response to viscosity and intense fluorescence emission. The TICT (twisted intramolecular charge transfer) of BDC was inhibited with an increase in viscosity, accompanied by a significant enhancement of red fluorescence signal with emission wavelength beyond 800 nm. Notably, BDC was able to noninvasively and sensitively monitor the viscosity changes in the glands of non-obese diabetic (NOD) mice model. BDC was utilized for monitoring SO2 in food and environmental samples through Michael addition reactions, providing a straightforward tool for SO2 detection in food safety and environmental monitoring.

Metformin treatment for a mouse model of diabetes during pregnancy reduces placental size and mitochondrial function but does not impact fetal growth.

Metformin treatment for a mouse model of diabetes during pregnancy reduces placental size and mitochondrial function but does not impact fetal growth.

Evaluations of the in vitro and in vivo antidiabetic activity of 70 % ethanolic fruit extracts of Rosa abyssinica

BackgroundDiabetes mellitus is becoming major health challenge with continually increasing burden. High costs of conventional medicines and numerous side effects associated with them, on the other hand, easy availability and accessibility of traditional herbal medicines calls upon experimental investigations to validate their effect on lowering blood glucose level. MethodsThe dried fruit of Rosa abyssinica was macerated with 70 % ethanol and the extract's in vitro antidiabetic activity was investigated using dinitrosalisylic acid method for alpha amylase inhibitory activity. Furthermore, the in vivo hypoglycemic and Antihyperglycemic effects of various doses of the extract (100, 200 and 400 mg/kg) was determined on normoglycemic, glucose loaded (1500 mg/kg) and Streptozotocine (180 mg/kg)-induced diabetic mice models. ResultsThe acute oral toxicity study revealed the plant showed no toxic effect on swiss albino mice at 2000 mg/kg. The in vitro alpha amylase inhibitory activity study showed that the extract has comparable IC50 value of 21.37 ± 4.252 μg/ml with the standard drug acarbose (IC50 value of 26.72 ± 3.59 μg/ml). On the other hand, in normal mice, none of the dose levels except at 400 mg/kg significantly reduces blood glucose level. This is in contrast to the oral glucose tolerance test, which the extract produced significant reduction at 60, 90 and 120 min following glucose challenge. The 70 % ethanolic fruit extracts of Rosa abyssinica also experienced profound antidiabetic activity in streptozotocin-induced diabetic model. In the single-dose study, both RAFE200 and RAFE400 demonstrated a significant (P˂0.05) reduction in blood glucose levels at 1, 2, 3, and 4 h. Similarly, in the repeated-dose study, RAFE200 and RAFE400 not only significantly reduced blood glucose levels but also produced a notable improvement in animal body weight. ConclusionThe 70 % ethanolic fruit extracts of Rosa abyssinica have shown significant in vitro alpha amylase inhibition effect and an in vivo blood glucose level lowering effects in diabetic mice.Therefore, this study supports the traditional use of Rosa abyssinica in the management of diabetes mellitus.

Monitoring cysteine changes and assessing ferroptosis in diabetic mice with a lysosome-targeted near-infrared fluorescence probe

Diabetes, characterized by elevated blood sugar levels, often leads to various complications. Cysteine (Cys), a biomarker of oxidative stress, is crucial in the progression of diabetes and its complications. Unfortunately, up until now, fluorescent probes for imaging lysosomal Cys in diabetic mouse models have not been available. Ferroptosis, linked to antioxidant damage in the lysosomal Cys/GPX4 axis, plays a significant role in diabetes. Visualizing lysosomal Cys is vital for assessing ferroptosis and understanding diabetes. We introduce a new near-infrared (NIR) fluorescent probe, NIR-Lys-Cys, designed to detect lysosomal Cys in living cells and diabetic mouse models. This probe shows exceptional selectivity and sensitivity towards Cys, along with superior fluorescence characteristics, enabling detection of Cys in living cells. NIR-Lys-Cys can monitor ferroptosis and its inhibition by measuring lysosomal Cys levels and has been used to detect ferroptosis in glucose-induced diabetic cells. It revealed significantly lower Cys concentrations in the livers of diabetic mice compared to healthy controls. Administering antidiabetic medication increased Cys production in diabetic mice. These findings highlight the potential of NIR-Lys-Cys as a tool for elucidating the role of Cys in lysosome-related diseases, providing critical insights into diagnosis and treatment strategies for diabetes and its complications.

Müller Cells Harboring Exosomal lncRNA OGRU Modulate Microglia Polarization in Diabetic Retinopathy by Serving as miRNA Sponges.

Diabetic retinopathy (DR) is one of the most common complications of diabetes mellitus which is associated with visual loss and blindness worldwide. However, the effective treatments for both early- and late-stage DR remains lacking. A streptozotocin (STZ)-induced diabetic mice model and high glucose (HG)-treated Müller cell model were established. M1/M2 microglia polarization was assessed by immunofluorescence (IF) staining and flow cytometry. Expression of lncRNA OGRU, cytokines and other key molecules were detected by qRT-PCR or western blot. ELISA assay was employed to monitor cytokine secretion. Müller cell-derived exosomes were isolated and characterized by nanopartical tracking analysis (NTA), western blot and transmission electron microscopy (TEM), and exosome uptake assay was used to monitor the intercellular transport of exosomes. Associations among lncRNA-miRNA-mRNA networks were validated by RNA pull-down and RNA immunoprecipitation (RIP) and dual luciferase assays. Increased M1 polarization but decreased M2 polarization of retinal microglia were observed in DR mice. HG-treated Müller cell-derived exosomes transported OGRU into microglia and promoted microglia polarization toward M1 phenotype. Mechanistically, OGRU served as a competing endogenous RNA (ceRNA) for miR-320-3p, miR-221-3p and miR-574-5p to regulate AR, PFKFB3 and GLUT1 expression in microglia, respectively. Loss of miR-320-3p/miR-221-3p/miR-574-5p or reinforced AR/PFKFB3/GLUT1 abrogated OGRU silencing-mediated microglia polarization in vitro. In vivo studies further showed that OGRU/miR-320-3p/AR, OGRU/miR-221-3p/PFKFB3 and OGRU/miR-574-5p/GLUT1 axes regulated microglia polarization in DR mice. Collectively, Müller cells-derived exosomal OGRU regulated microglia polarization in DR via modulating OGRU/miR-320-3p/AR, OGRU/miR-221-3p/PFKFB3 and OGRU/miR-574-5p/GLUT1 axes.

Deficiency of thiosulfate sulfurtransferase mediates the dysfunction of renal tubular mitochondrial fatty acid oxidation in diabetic kidney disease.

One of the main characteristics of diabetic kidney disease (DKD) is abnormal renal tubular fatty acid metabolism, especially defective fatty acid oxidation (FAO), accelerating tubular injury and tubulointerstitial fibrosis. Thiosulfate sulfurtransferase (TST), a mitochondrial enzyme essential for sulfur transfer, is reduced in metabolic diseases like diabetes and obesity. However, the potential role of TST in regulating fatty acid metabolic abnormalities in DKD remains unclear. Here, our data revealed decreased TST expression in the renal cortex of DKD patients. TST deficiency exacerbated tubular impairment in both diabetic and renal fibrosis mouse models, while sodium thiosulfate treatment or TST overexpression mitigated renal tubular injury with high-glucose exposure. TST downregulation mediated the decrease in S-sulfhydration of very long-chain specific acyl-CoA dehydrogenase, resulting in mitochondrial FAO dysfunction. This sequence of events exacerbates the progression of tubulointerstitial injury in DKD. Together, our findings demonstrate TST as a regulator of renal tubular injury in DKD.

Ubiquitin-specific protease 38 promotes atrial fibrillation in diabetic mice by stabilizing iron regulatory protein 2

BackgroundAtrial fibrillation (AF) is a common cardiovascular disease often observed in diabetes mellitus, and there is currently no satisfactory therapeutic option. Ubiquitin-specific protease 38 (USP38) has been implicated in the degradation of numerous substrate proteins in the myocardium. Herein, we aim to investigate the role of USP38 in AF induced by diabetes. MethodsCardiac-specific transgenic USP38 mice and cardiac-specific knockout USP38 mice were constructed, and streptozotocin was used to establish diabetic mouse model. Functional, electrophysiological, histologic, biochemical studies were performed. ResultsThe expression of USP38 was upregulated in atrial tissues of diabetic mice and HL-1 cells exposed to high glucose. USP38 overexpression increased susceptibility to AF, accompanied by aberrant expression of calcium-handling protein, heightened iron load and oxidation stress in diabetic mice. Conversely, USP38 deficiency reduced vulnerability to AF by hampering ferroptosis. Mechanistically, USP38 bound to iron regulatory protein 2 (IRP2), stabilizing it and remove K48-linked polyubiquitination chains, thereby increasing intracellular iron overload, lipid peroxidation, and ultimately contributing to ferroptosis. In addition, reduced iron overload by deferoxamine treatment alleviated oxidation stress and decreased vulnerability to AF in diabetic mice. ConclusionOverall, our findings reveal the detrimental role of USP38 in diabetes-related AF, manifested by increased level of iron overload and oxidation stress.

Advanced glycation end products mediate biomineralization disorder in diabetic bone disease

Patients with diabetes often experience fragile fractures despite normal or higher bone mineral density (BMD), a phenomenon termed the diabetic bone paradox (DBP). The pathogenesis and therapeutics opinions for diabetic bone disease (DBD) are not fully explored. In this study, we utilize two preclinical diabetic models, the leptin receptor-deficient db/db mice (DB) mouse model and the streptozotocin-induced diabetes (STZ) mouse model. These models demonstrate higher BMD and lower mechanical strength, mirroring clinical observations in diabetic patients. Advanced glycation end products (AGEs) accumulate in diabetic bones, causing higher non-enzymatic crosslinking within collagen fibrils. This inhibits intrafibrillar mineralization and leads to disordered mineral deposition on collagen fibrils, ultimately reducing bone strength. Guanidines, inhibiting AGE formation, significantly improve the microstructure and biomechanical strength of diabetic bone and enhance bone fracture healing. Therefore, targeting AGEs may offer a strategy to regulate bone mineralization and microstructure, potentially preventing the onset of DBD.

Synbiotic supplementation with xylooligosaccharide derived probiotic Lactobacillus gasseri and prebiotic mixture exerts antidiabetic effects via collaborative action

The guts of young humans and animals are abundant in various beneficial bacteria, and certain probiotics have a remarkable blood glucose-regulating impact on diabetic mice. This study adopts a novel approach based on the separation and purification after prebiotics enrich probiotics entering the stable stage to explore synbiotics, which is more rapid and circumvents difficulties such as difficult intestinal entry, long time consumption, and challenges in finding matching synbiotics. Through measuring the inhibitory activity on α-glucosidase and α-amylase in vitro and its probiotic characteristics, Lactobacillus gasseri Y11 is screened and identified. Utilizing a high-fat diet combined with streptozotocin to establish a diabetic mouse model, the hypoglycemic mechanism of synbiotics in type 2 diabetic mice is investigated. The association between the gut microbiota and serum indices and genes is analyzed using the Mantel test and Spearman correlation analysis. The findings indicate that different intervention groups can ameliorate body weight and HDL-C, and reduce FBG, TG, TC, LDL-C, HbA1C, INS, HOMA-IR, and QUICK1 levels, enhancing blood glucose homeostasis, blood lipid levels, and insulin sensitivity of mice, and regulating the expression of genes like GIP, GLP-1, PPARγ, PEPCK, G6PASE, MTOR-S6K1, and GLUT-2 in the ileum and liver. Additionally, 16S rRNA gene sequencing is employed to analyze the gut microbiota. In the Synbiotics group, the relative abundance of Bifidobacterium and Akkermansia is increased. In summary, this study devises a new synbiotics screening strategy, explores its potential in treating type 2 diabetes, and provides a new research direction for the anti-diabetic mechanism.

The effects of Hibiscus sabdariffa Linn. on the levels of FGF21 and AMPK in the Heart of Diabetic Mice

Background : Diabetes Mellitus (DM) is a metabolic disorder characterized by pancreatic cell dysfunction and insulin resistance. Fibroblast Growth Factor 21 (FGF21) is thought to have a cardioprotective role. Through FGF21 signaling, AMP-activated protein kinase (AMPK) activity reduces apoptosis, inflammation, hypertrophy, and fibrosis in the heart. Hibiscus sabdariffa Linn. (HSL) contains flavonoids that have hypoglycemic effects and are anti-inflammatory and antioxidant-active. This study aims to assess the effect of HSL on FGF21 and AMPK levels in the heart of diabetic mice models. Methods : An experimental study using Deutschland Denken Yoken (DDY) mice aged eight weeks were divided into four groups: Control, DM Control, HSL 200, and HSL 400. In the DM control, HSL 200, and HSL 400 groups, diabetes was induced by giving a High Fat Diet(HFD) and STZ 40mg/kgbb. The HSL 200 group was given HSL 200mg/kgBB supplementation for three weeks, and the HSL 400 group was given HSL 400 mg/kgBB supplementation for three weeks. FGF21 and AMPK levels were measured using the enzyme-linked immunosorbent assay (ELISA) method. Results : There was no significant difference between FGF21 and AMPK levels between the control and DM control groups. FGF21 and AMPK levels in the HSL 400 group were higher than in the control, DM control, and HSL 200 groups. Conclusions : These findings suggest that HSL supplementation at specific doses can potentially increase the activation of FGF 21 and AMPK signaling in the heart of diabetic mice models.

Liraglutide Promotes Diabetic Wound Healing via Myo1c/Dock5.

Non-healing diabetic wounds and ulcer complications, with persistent cell dysfunction and obstructed cellular processes, are leading causes of disability and death in patients with diabetes. Currently, there is a lack of guideline-recommended hypoglycemic drugs in clinical practice, likely due to limited research and unclear mechanisms. In this study, it is demonstrated that liraglutide significantly accelerates wound closure in diabetic mouse models (db/db mice and streptozotocin-induced mice) by improving re-epithelialization, collagen deposition, and extracellular matrix remodeling, and enhancing the proliferation, migration, and adhesion functions of keratinocytes. However, these effects of improved healing by liraglutide are abrogated in dedicator of cytokinesis 5 (Dock5) keratinocyte-specific knockout mice. Mechanistically, liraglutide induces cellular function through stabilization of unconventional myosin 1c (Myo1c). Liraglutide directly binds to Myo1c at arginine 93, enhancing the Myo1c/Dock5 interaction by targeting Dock5 promoter and thus promoting the proliferation, migration, and adhesion of keratinocytes. Therefore, this study provides insights into liraglutide biology and suggests it may be an effective treatment for diabetic patients with wound-healing pathologies.

Assessing anti oxidant, antidiabetic potential and GCMS profiling of ethanolic root bark extract of Zanthoxylum rhetsa (Roxb.) DC: Supported by in vitro, in vivo and in silico molecular modeling.

Zanthoxylum rhetsa (ZR) is used traditionally to manage a variety of ailments, including diabetes. Oxidative stress may accelerate the diabetic condition. The available antidiabetic and antioxidant drugs have many shortcomings including resistance, inefficiency, higher dose, side effects and costs. The goal of the current investigation was to assess the antioxidant capacity and antidiabetic activity of an ethanolic extract of Zanthoxylum rhetsa root bark (ZRRB) through in vitro, in vivo, and in silico methods. The antioxidant capacity of the ZRRB extract was measured using both the DPPH radical assay and the total antioxidant activity test. The oral glucose tolerance test (OGTT) and alloxan-induced diabetic mice model were also used to examine in vivo antidiabetic efficacy. Phytochemicals identification was done by GCMS analysis. Additionally, computational methods such as molecular docking, ADMET analysis, and molecular dynamics (MD) modeling were performed to determine the above pharmacological effects. The extract demonstrated significant DPPH scavenging activity (IC50 = 42.65 μg/mL). In the OGTT test and alloxan-induced diabetes mice model, the extract effectively lowered blood glucose levels. Furthermore, in vitro inhibition of pancreatic α-amylase studies demonstrated the ZRRB extract as a good antidiabetic crude drug (IC50 = 81.45 μg/mL). GCMS investigation confirmed that the crude extract contains 16 major phytoconstituents, which were docked with human peroxiredoxin-5, α-amylase, and sulfonylurea receptor 1. Docking and pharmacokinetic studies demonstrated that among 16 phytoconstituents, 6H-indolo[3,2,1-de] [1,5]naphthyridin-6-one (CID: 97176) showed the highest binding affinity to targeted enzymes, and imitated Lipinski's rule of five. Furthermore, MD simulation data confirmed that the aforementioned compound is very steady to the binding site of α-amylase and sulfonylurea receptor 1 receptors. Findings from in vitro, in vivo and in silico investigation suggest that ZRRB extract contains a lead compound that could be a potent source of antidiabetic drug candidate.

Polysaccharide fraction from Triplostegia glandulifera Wall and its renoprotective effect in streptozotocin-induced diabetic mice by attenuating oxidative stress

Triplostegia glandulifera Wall (T. glandulifera) is an ethnomedicine commonly used by ethnic minorities in Yunnan, China, to treat kidney disease. However, there are few reports on the renoprotective effects of this substance, and the active ingredients remain unclear. In this study, we extracted the polysaccharide fractions TGB and TGC using the water extraction-alcohol precipitation method and determined their molecular weight (Mw) and monosaccharide composition. The study investigated the protective effects of TGB and TGC fractions against diabetic nephropathy (DN) using an in vitro high glucose-induced HRMCs model and an in vivo STZ-induced diabetic mouse model. HPLC analysis revealed that TGB contained D-galacturonic acid, D-glucose, D-galactose, and D-arabinose, and had a lower Mw than TGC. In vitro, TGB showed concentration-dependent antioxidant activity and effectively reduced abnormal proliferation and while attenuating oxidative stress in HRMCs. In mice with diabetes, TGB corrected the dysregulation of glucose-lipid metabolism and alleviated oxidative stress in the kidneys. Additionally, it improved renal function and reduced renal tissue damage. The study suggests that the low Mw polysaccharides (TGB) have better activity against DN through the antioxidative stress mechanism.Graphical

Ethyl Acetate Fractions of Salvia miltiorrhiza Bunge (Danshen) Crude Extract Modulate Fibrotic Signals to Ameliorate Diabetic Kidney Injury.

Diabetic nephropathy, a leading cause of end-stage renal disease, accounts for significant morbidity and mortality. It is characterized by microinflammation in the glomeruli and myofibroblast activation in the tubulointerstitium. Salvia miltiorrhiza Bunge, a traditional Chinese medicine, is shown to possess anti-inflammatory and anti-fibrotic properties, implying its renal-protective potential. This study investigates which type of component can reduce the damage caused by diabetic nephropathy in a single setting. The ethyl acetate (EtOAc) layer was demonstrated to provoke peroxisome proliferator-activated receptor (PPAR)-α and PPAR-γ activities in renal mesangial cells by dual luciferase reporter assay. In a high glucose (HG)-cultured mesangial cell model, the EtOAc layer substantially inhibited HG-induced elevations of interleukin-1β, transforming growth factor-β1 (TGF-β1), and fibronectin, whereas down-regulated PPAR-γ was restored. In addition, among the extracts of S. miltiorrhiza, the EtOAc layer effectively mitigated TGF-β1-stimulated myofibroblast activation. The EtOAc layer also showed a potent ability to attenuate renal hypertrophy, proteinuria, and fibrotic severity by repressing diabetes-induced proinflammatory factor, extracellular matrix accumulation, and PPAR-γ reduction in the STZ-induced diabetes mouse model. Our findings, both in vitro and in vivo, indicate the potential of the EtOAc layer from S. miltiorrhiza for future drug development targeting diabetic nephropathy.

Hyperglycemia in a NOD Mice Model of Type-I Diabetes Aggravates Collagenase-Induced Intracerebral Hemorrhagic Injury.

Intracerebral hemorrhage (ICH) is a severe type of stroke with high mortality. Persistent hyperglycemia following ICH is linked to deteriorated neurological functions and death. However, the exacerbating effect of hyperglycemia on ICH injury at the molecular level is still unclear. Therefore, this study explores the impact of diabetes on ICH injury using a non-obese diabetic (NOD) mouse model of type I diabetes mellitus. NOD and non-diabetic (non-obese resistant) mice subjected to ICH by intrastriatal injection of collagenase were sacrificed three days following the ICH. Brains were collected for hematoma volume measurement and immunohistochemistry. Neurobehavioral assays were conducted 24 h before ICH and then repeated at 24, 48 and 72 h following ICH. NOD mice showed increased hematoma volume and impairment in neurological function, as revealed by rotarod and grip strength analyses. Immunohistochemical staining showed reduced glial cell activation, as indicated by decreased GFAP and Iba1 staining. Furthermore, the expression of oxidative/nitrosative stress markers represented by 3-nitrotyrosine and inducible nitric oxide synthase was reduced in the diabetic group. Overall, our findings support the notion that hyperglycemia exacerbates ICH injury and worsens neurological function and that the mechanism of injury varies depending on the type of diabetes model used.

20(S)-ginsenoside Rg3 protects against diabetic muscle atrophy by promoting myoblastic differentiation and protecting mitochondrial function

BackgroundHigh glucose levels are a primary cause of diabetes-associated cellular dysfunction and tissue damage. Muscles are the key insulin target organ and therefore, have a high level of sensitivity to hyperglycemia. Our previous study revealed that 20(S)-ginsenoside Rg3 (S-Rg3) is a monomer with a good myogenic differentiation effect in ginsenoside. Furthermore, it can alleviate dexamethasone-induced muscle atrophy by protecting mitochondrial function. However, whether S-Rg3 is effective for diabetic-induced muscle atrophy has not been reported. PurposeThis study aimed to investigate the protective effect of S-Rg3 on diabetic-induced muscle atrophy. MethodsC2C12 myoblasts, Drosophila, and mice were used as model systems, and the protective effect of S-Rg3 on diabetes was evaluated by assessing the levels of glucose and lipids. Furthermore, H&E, toluidine blue, Giemsa, and immunofluorescence staining were performed to detect the effects of S-Rg3 on muscle atrophy and myogenic differentiation. Moreover, the effects of S-Rg3 on mitochondrial morphology and function were also evaluated by electron microscopy, flow cytometry, and Seahorse. In addition, the underlying pathways of S-Rg3 effects were detected by Western blot. The related inhibitors and gene mutations in Drosophila were used for validation. ResultsThe analysis of diabetic mice model fed with a high-fat diet (HFD) and high glucose (HG) revealed that in the injured C2C12 myoblasts, S-Rg3 treatment significantly reduced the levels of triglycerides and glucose. Furthermore, it promoted the differentiation of myoblasts and inhibited mitochondrial dysfunction. In the Drosophila HG and HFD diabetic model, S-Rg3 reduced triglyceride and trehalose levels, increased climbing distance values, promoted myoblasts differentiation, preserved mitochondrial function, and inhibited muscle atrophy. Mechanistically, the beneficial effects of S-Rg3 were at least partially associated with the phosphorylation of AMPK and FoxO3 together with the inhibition of Smad3 phosphorylation, this pathway was validated by the UAS-AMPKα-RNAi Drosophila model. ConclusionIn summary, this study revealed mechanistic insights into how S-Rg3 protects against diabetes-associated muscle atrophy in cells, Drosophila, and mice.

The STAT1-SLC31A1 axis: Potential regulation of cuproptosis in diabetic retinopathy

BackgroundBy identifying molecular biological markers linked to cuproptosis in diabetic retinopathy (DR), new pathobiological pathways and more accessible diagnostic markers can be developed. MethodsThe datasets related to DR were acquired from the Gene Expression Omnibus database, while genes associated with cuproptosis were sourced from previously published compilations. Consensus clustering was conducted to delineate distinct DR subclasses. Feature genes were identified utilizing weighted correlation network analysis (WGCNA). Additionally, two machine-learning algorithms were employed to refine the selection of feature genes. Finally, we conducted preliminary validation experiments to ascertain the involvement of cuproptosis in DR development and the transcriptional regulation of critical genes using both the streptozotocin-induced diabetic mouse model and the high glucose-induced BV2 model. ResultsIn the STZ-induced diabetic mouse retinas, a decrease in the expression of cuproptosis signature proteins (FDX1, DLAT, and NDUFS8) suggested the occurrence of cuproptosis in DR. Subsequently, the expression of eight cuproptosis differential genes was validated through the STZ-induced diabetes and oxygen-induced retinopathy (OIR) models, with the key gene SLC31A1 showing upregulation in both models and dataset species. Further analyses, including weighted gene co-expression network analysis, GSVA, and immune infiltration analysis, indicated a close correlation between cuproptosis and microglia function. Additionally, validation in an in vitro model of microglia indicated the occurrence of cuproptosis in microglia under high glucose conditions, alongside abnormal expression of STAT1 with SLC31A1. ConclusionOur findings suggest that STAT1/SLC31A1 may pave the way for a deeper comprehension of the mechanistic basis of DR and offer potential therapeutic avenues.