Obese Diabetic Mice Research Articles

The effect of TU-100 on hepatocarcinogenesis and colorectal liver metastasis in MASH model.

577 Background: TU-100 is most commonly used herbal medicine in clinical setting. We have already reported that TU-100 suppressed dysbiosis (J Med Invest, 2013), bacterial translocation (Surg Today, 2017) and hepatic fibrosis (Surgery, 2016). This time we investigate the effect of TU-100 on hepatocellular carcinoma (HCC) and colorectal liver metastasis (CRLM) in MASH model. Methods: 1: Effect on HCC: Seven-week-old Tsumura Suzuki obese diabetes mice, a model that shows the spontaneous onset of MASH and HCC, were used. They were divided into a TU-100 treated group and a control group. Mice were sacrificed at 24 and 48 weeks to evaluate hepatic steatosis, fibrosis, carcinogenesis, cytokine expression, and microbiome abundance. 2: Effect on CRLM: Six-week-old male C57BL/6J mice were used. They were divided into the western diet (WD) group and the WD+TU-100 group. MC38 colon cancer cells were injected into the spleen at 16 weeks, and mice were killed at 2 weeks after injection to evaluate hepatic steatosis, fibrosis and mRNA expression in the liver. Results: 1: Effect on HCC: At 24 weeks, the TU-100 group showed significantly lower expression of IL6, IL1B, and ACTA2 mRNA in the liver (P<0.05). At 48 weeks, the TU-100 group showed a lower rate of MASH than the control group (28% vs 72%; P=0.1). Tumor diameter was significantly smaller in the TU-100 group compared with that in the control group (P<0.05). Regarding the intestinal microbiome, the genera Blautia and Ruminococcus were increased in the TU-100 group (P<0.05), whereas Dorea and Erysipelotrichaceae were decreased in the TU-100 group (P<0.05). 2: Effect on CRLM: Steatosis of the WD+TU-100 group was significantly suppressed compared with the WD group (p<0.05). The WD+TU-100 group showed significantly smaller tumor diameter than the WD group (p<0.05). In the WD+TU-100 group, expression of SAA1 and TIMP1 mRNA in the liver was significantly lower than in the WD group (p<0.05). Conclusions: TU-100 regulates the intestinal microbiome and may suppress hepatic steatosis and subsequent hepatocarcinogenesis in the MASH model. Furthermore, TU-100 may have effect on CRLM via suppression of SAA1/TIMP1.

CDK1-loaded extracellular vesicles promote cell cycle to reverse impaired wound healing in diabetic obese mice.

Small extracellular vesicles (sEVs) mediate intercellular signaling to coordinate proliferation of cell types that promote re-epithelialization of skin following injury. Cyclin-dependent kinase 1 (CDK1) drives cell division and is a key regulator of entry to cell cycle. To understand the potential of sEV-mediated delivery of CDK1 to reverse impaired wound healing, we generated CDK1-loaded sEVs (CDK1-sEVs) and evaluated their ability to mediate cell proliferation, re-epithelialization and downstream signaling responses in the wound bed. We found that treatment of human keratinocytes with CDK1-sEVs increased phosphorylation of the CDK1 target, eukaryotic translation inhibition factor 4E-binding protein 1 (4E-BP1), and histone H3 within 24 hours via AKT and ERK phosphorylation, driving increased proliferation and cell migration. Treatment of the wound bed of diabetic obese mice, a model of delayed wound healing, with a single dose of CDK1-sEVs accelerated wound closure, increased re-epithelialization, and promoted proliferation of keratinocytes. These studies show that delivery of CDK1 by sEVs can stimulate selective and transient proliferation of cell types that increase re-epithelialization and promote proliferation of keratinocytes to accelerate wound healing.

Effect of Cordyceps militaris extract containing cordycepin on the adipogenesis and lipolysis of adipocytes.

Obesity, a global health concern, results from an energy imbalance leading to lipid accumulation. In the present study, Cordyceps militaris extract (CM) and its primary component, cordycepin, were investigated to characterize their potential effects on adipogenesis and lipolysis. Treatment with CM or cordycepin reduced lipid droplets and increased hormone-sensitive lipase activation in 3T3-L1 cells. In a diabetic obese mouse model, CM and cordycepin lowered serum low-density lipoprotein/very low-density lipoprotein levels and reduced oxidative stress and cell senescence markers. Thus, cordycepin inhibits preadipocyte differentiation and promotes lipolysis, which may serve as a novel obesity treatment. Further studies, including clinical trials, are required to validate the clinical potential of cordycepin.

Long-Lasting Exendin-4-Coated Gold Nanoparticles: Synthesis and In Vivo Evaluation of Hypoglycemic Activity.

Gold nanoparticles (NPs) have drawn great attention in the area of biomedical research with their relatively safe and versatile properties. This study aimed to synthesize long-lasting exendin-4-coated gold NPs (EX-ABD-AFF-GoldNPs) and evaluate their anti-diabetic effects in vivo. In the present study, EX-ABD-AFF-GoldNPs were synthesized using a simple one-step aqueous reduction method. The physical characterization of the prepared particles verified the successful formation of the EX-ABD-AFF-GoldNPs through dynamic light scattering (DLS), transmission electron microscopy (TEM), ultraviolet-visible (UV-VIS) light spectroscopy, and Fourier transform infrared spectroscopy (FTIR). The anti-hyperglycemic and anti-obesity effects were assessed in high-fat diet (HFD)-fed obese diabetic mice. Additionally, pharmacokinetics (PK) and biodistribution studies were performed to verify the long-lasting properties. The EX-ABD-AFF-GoldNPs were conglomerates of smaller globular-shaped particles, and the average size was 110(±14) nm, based on the TEM images. Safety assessments using Min6, HepG2, and B16F10 cell lines demonstrated low cytotoxicity, with over 80% cell viability up to the highest tested concentration of 150 μg/mL (as EX-ABD-AFF). Notably, the animal studies showed that the EX-ABD-AFF-GoldNPs exhibited significant hypoglycemic activity, comparable to the EX-ABD-AFF, in the HFD-fed mice. A 4-week treatment with EX-ABD-AFF-GoldNPs produced similar reductions in blood glucose and body weight to the EX-ABD-AFF, without any apparent toxicity. Furthermore, the PK and biodistribution study results confirmed the long-lasting properties (plasma half-life: 43.6 h) of the particles. Overall, this study demonstrated that the preparation of therapeutic protein-loaded gold NPs is feasible and, despite their much larger size compared with the protein, EX-ABD-AFF-GoldNPs can be successfully absorbed through the subcutaneous route and show nearly equivalent hypoglycemic activity to the EX-ABD-AFF protein. Finally, this study showed that long-lasting properties could be acquired by only coating EX-ABD-AFF onto gold NPs.

TRAIL induces podocyte PANoptosis via death receptor 5 in diabetic kidney disease

Podocytes can undergo PANoptosis (apoptosis, pyroptosis, and necroptosis). Diabetic kidney disease (DKD) is the leading cause of kidney failure, and podocyte loss is a major event leading to the progression of DKD. Here, we compared single cell RNA sequencing (scRNA-seq) data between three normal and three DKD human kidney samples and found a significant increase of TNFSF10 and TNFRSF10B expression in podocytes of patients with DKD. Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), coded by TNFSF10, belongs to the TNF superfamily members and TNFRSF10B codes for death receptor 5 (DR5). We confirmed that expression of TRAIL and DR5 increased in podocytes of patients with DKD and correlated with the severity of DKD. Invitro, TNF-α stimulated TRAIL and DR5 expression in cultured human podocytes. Silence of TRAIL or DR5 by small interfering RNA alleviated TNF-α-stimulated podocytes PANoptosis, while overexpression of TRAIL, treatment with recombinant human TRAIL (rh-TRAIL) or the DR5 activator (Bioymifi) enhanced podocytes PANoptosis. Invivo, podocyte-specific deletion of TNFSF10 or TNFRSF10B alleviated podocyte and glomerular injury in high fat diet and streptozotocin-induced obese diabetic mice and was associated with decreased podocyte PANoptosis. Conversely, the induction of TNFSF10 overexpression specifically in podocytes exacerbated albuminuria and kidney injury in diabetic mice with increased podocyte PANoptosis. Additionally, administration of soluble DR5-Fc, an inhibitor of DR5, resulted in a marked reduction in albuminuria and glomerular injury in BTBR ob/ob mice. Our findings suggest a critical autocrine role of TRAIL/DR5 in inducing podocyte injury in DKD via activation of PANoptosis.

Duodenal-Jejunal Bypass Surgery in Diet-Induced Obese Diabetic Mice.

The prevalence of obesity and type 2 diabetes is a serious global health concern. Obesity is a major pathogenic factor in type 2 diabetes, cardiovascular disease, and some cancers. Bariatric surgery offers a long-term and effective treatment option for both obesity and diabetes. Sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) are widely recognized as the most popular bariatric surgeries. Additionally, several exploratory bariatric surgeries have demonstrated promising therapeutic effects. Duodenal-jejunal bypass (DJB), specifically tailored for diabetics with low body mass index, has shown beneficial metabolic outcomes. However, its weight-independent metabolic benefits are not fully understood due to limited animal models. In this article, we describe the optimized care protocols and surgical techniques for performing DJB surgery in diet-induced obese (DIO) diabetic mice. Using a mouse model contributes to a better understanding of the nature of changes induced by DJB surgery while facilitating related clinical practice.

Glucocorticoid chronopharmacology promotes glucose metabolism in heart through a cardiomyocyte-autonomous transactivation program.

Circadian time of intake gates the cardioprotective effects of glucocorticoid administration in both healthy and infarcted hearts. The cardiomyocyte-specific glucocorticoid receptor (GR) and its cofactor, Krüppel-like factor 15 (KLF15), play critical roles in maintaining normal heart function in the long term and serve as pleiotropic regulators of cardiac metabolism. Despite this understanding, the cardiomyocyte-autonomous metabolic targets influenced by the concerted epigenetic action of the GR/KLF15 axis remain undefined. Here, we demonstrated the critical roles of the cardiomyocyte-specific GR and KLF15 in orchestrating a circadian-dependent glucose oxidation program within the heart. Combining integrated transcriptomics and epigenomics with cardiomyocyte-specific inducible ablation of GR or KLF15, we identified their synergistic role in the activation of adiponectin receptor expression (Adipor1) and the mitochondrial pyruvate complex (Mpc1/2), thereby enhancing insulin-stimulated glucose uptake and pyruvate oxidation. Furthermore, in obese diabetic (db/db) mice exhibiting insulin resistance and impaired glucose oxidation, light-phase prednisone administration, as opposed to dark-phase prednisone dosing, restored cardiomyocyte glucose oxidation and improved diastolic function. These effects were blocked by combined in vivo knockdown of GR and KLF15 levels in db/db hearts. In summary, this study leveraged the circadian-dependent cardioprotective effects of glucocorticoids to identify cardiomyocyte-autonomous targets for the GR/KLF15 axis in glucose metabolism.

Fibroblast-specific TGF-β signaling mediates cardiac dysfunction, fibrosis, and hypertrophy in obese diabetic mice.

Transforming growth factor (TGF)-β is up-regulated in the diabetic myocardium and may mediate fibroblast activation. We aimed at examining the role of TGF-β-induced fibroblast activation in the pathogenesis of diabetic cardiomyopathy. We generated lean and obese db/db mice with fibroblast-specific loss of TbR2, the Type 2 receptor-mediating signaling through all three TGF-β isoforms, and mice with fibroblast-specific Smad3 disruption. Systolic and diastolic function, myocardial fibrosis, and hypertrophy were assessed. Transcriptomic studies and in vitro experiments were used to dissect mechanisms of fibroblast activation. Fibroblast-specific TbR2 loss attenuated systolic and diastolic dysfunction in db/db mice. The protective effects of fibroblast TbR2 loss in db/db mice were associated with attenuated fibrosis and reduced cardiomyocyte hypertrophy, suggesting that in addition to their role in fibrous tissue deposition, TGF-β-stimulated fibroblasts may also exert paracrine actions on cardiomyocytes. Fibroblast-specific Smad3 loss phenocopied the protective effects of fibroblast TbR2 loss in db/db mice. Db/db fibroblasts had increased expression of genes associated with oxidative response (such as Fmo2, encoding flavin-containing monooxygenase 2), matricellular genes (such as Thbs4 and Fbln2), and Lox (encoding lysyl oxidase). Ingenuity pathway analysis (IPA) predicted that neurohumoral mediators, cytokines, and growth factors (such as AGT, TGFB1, and TNF) may serve as important upstream regulators of the transcriptomic profile of diabetic mouse fibroblasts. IPA of scRNA-seq data identified TGFB1, p53, MYC, PDGF-BB, EGFR, and WNT3A/CTNNB1 as important upstream regulators underlying fibroblast activation in db/db hearts. Comparison of the transcriptome of fibroblasts from db/db mice with fibroblast-specific Smad3 loss and db/db Smad3 fl/fl controls identified Thbs4 [encoding thrombospondin-4 (TSP-4), a marker of activated fibroblasts] as a candidate diabetes-induced fibrogenic mediator. However, in vitro experiments showed no significant activating effects of matricellular or intracellular TSP-4 on cardiac fibroblasts. Fibroblast-specific TGF-β/Smad3 signaling mediates ventricular fibrosis, hypertrophy, and dysfunction in Type 2 diabetes.

Once-daily oral administration of gpr55 agonist ml-184 has direct and indirect benefits on [beta]-cell and gastrointestinal health in obese-diabetic mice

Once-daily oral administration of gpr55 agonist ml-184 has direct and indirect benefits on [beta]-cell and gastrointestinal health in obese-diabetic mice

The dual glucose-dependent insulinotropic polypeptide/glucagon-like peptide-1 receptor agonist tirzepatide effects on body weight evolution, adiponectin, insulin and leptin levels in the combination of obesity, type 2 diabetes and menopause in mice.

Tirzepatide (Tzp), a novel dual agonist glucose-dependent insulinotropic polypeptide/glucagon-like peptide-1, is approved for treating insulin resistance and obesity, and menopausal women consuming a high-calorie diet are a target to study the Tzp effect. Therefore, we aimed to allometrically scale body weight (BW) in Tzp-treated obese diabetic menopausal mice. Three-month-old C57BL/6 female mice had bilateral ovariectomy (Ovx) or a sham procedure and for 12 weeks were fed a control diet or a high-fat and high sucrose diet (n = 120/each group [control (C), obese diabetic (Od), Ovx (O), sham (S), Tzp (T)]). Tzp was subcutaneously administered (10 nmol/kg) or vehicle once a day for an additional 4 weeks. The analysis considered log-transformed data and the allometric equation log y = log a + b log x. Od and OdO showed more upward slopes than C and CO. In C, BW was non-allometric by T administration. Od and OdO showed slightly positive slopes (more prominent in OdO than Od). OdT and OdOT showed negative slopes, significant intercepts, and more robust Pearson coefficients than untreated ones. A potent drug effect was seen with BW allometric decline. Interactions between diet versus Ovx and diet versus Tzp affected weight gain. Diet versus Ovx versus Tzp affected food intake. A model was developed to show three usual factors observed in mature women. Notably, Tzp improved the metabolism and weight loss of OdO mice. Tzp-treated mice showed negative allometric BW across treatment time, which is a quantitative assessment that allows better comparison between results.

Magnesium from Deep Seawater as a Potentially Effective Natural Product against Insulin Resistance: A Randomized Trial.

Background and Objectives: Deep seawater has been shown to restore pancreatic function in obese diabetic mice and considerably improve the homeostatic model assessment for insulin resistance, total cholesterol, and low-density lipoprotein cholesterol concentrations in patients with impaired fasting glucose or glucose tolerance. In this study, the effect of 12-week daily consumption of magnesium (Mg2+)-containing deep seawater mineral extracts on blood glucose concentration and insulin metabolism-associated indicators was investigated in patients with impaired glucose tolerance. Materials and methods: In this 12-week randomized, double-blind trial, patients (n = 37) with impaired glucose tolerance consumed deep seawater mineral extracts. Changes in blood glucose concentration and related indicators were compared between the treatment group and placebo group (n = 38). Results: The fasting insulin, C-peptide, homeostatic model assessment for insulin resistance, quantitative insulin sensitivity check index, homeostatic model assessment of beta-cell function, and Stumvoll insulin sensitivity index values in the deep seawater mineral extract group showed improvements compared with the placebo group. However, no significant differences between groups were observed in fasting blood glucose, postprandial blood glucose, glycated hemoglobin, or incremental area under the curve values. Conclusions: Oral supplementation with deep seawater mineral extracts enriched in Mg2+ markedly improves insulin sensitivity in patients with pre-diabetes. This study illustrates the potential clinical application of natural Mg2+ from deep seawater to alleviate insulin resistance in patients with pre-diabetes. Trial registration: This trial was retrospectively registered with Clinical Research information Service (CRIS), No. KCT0008695, on 8 August 2023.

Combined therapeutic use of umbilical cord blood serum and amniotic membrane in diabetic wounds

Diabetic wounds are hard-to-heal due to complex multifactorial dysregulation within the micro-environment, necessitating the development of novel regenerative approaches to stimulate healing. This study investigated whether the combined therapeutic application of two novel cellular tissue products, namely a decellularized collagen-rich amniotic membrane (AmR) and growth factor-rich umbilical cord blood serum (UCBS) could have a positive synergistic effect on long-term healing outcomes by stimulating both superficial wound closure and wound bed regeneration. Full thickness excisional wounds were induced on obese diabetic mice (B6.Cg-lepob/J, ob/ob, n = 23) and treated with either: 1) Standard wound care (control); 2) UCBS; 3) AmR or 4) UCBS + AmR. Macroscopic wound closure was assessed on days 0, 3, 7, 10 and 14 post wounding. To determine the potential impact on wound recurrence, endpoint analysis was performed to determine both the overall quality of healing histologically as well as the molecular state of the wounds on day 14 via proteomic analysis. The data demonstrated the presence of both healers and non-healers. Re-epithelization took place in the healers of all treatment groups, but underlying tissue regeneration was far more pronounced following application of the combined treatment (UCBS + AmR), suggesting improved quality of healing and potentially a reduced change of recurrence long term. In non-healers, wounds failed to heal due to excessive slough formation and a reduction in LTB4 expression, suggesting impaired antimicrobial activity. Care should thus be taken since the cellular tissue product therapy could pose an increased risk for infection in some patients.

Interplay between cardiac O-GlcNAcylation and cardiac dysfunction in obese diabetic mice

Interplay between cardiac O-GlcNAcylation and cardiac dysfunction in obese diabetic mice

Inhibition of de novo ceramide synthesis by sirtuin-1 improves beta-cell function and glucose metabolism in type 2 diabetes.

Obesity and type 2 diabetes (T2D) are major risk factors for cardiovascular (CV) diseases. Dysregulated pro-apoptotic ceramide synthesis reduces β-cell insulin secretion, thereby promoting hyperglycaemic states that may manifest as T2D. Pro-apoptotic ceramides modulate insulin sensitivity and glucose tolerance while being linked to poor CV outcomes. Sirtuin-1 (SIRT1) is a NAD + -dependent deacetylase that protects against pancreatic β-cell dysfunction; however, systemic levels are decreased in obese-T2D mice and may promote pro-apoptotic ceramide synthesis and hyperglycaemia. Herein, we aimed to assess the effects of restoring circulating SIRT1 levels to prevent metabolic imbalance in obese and diabetic mice. Circulating SIRT1 levels were reduced in obese-diabetic mice (db/db) as compared to age-matched non-diabetic db/+ controls. Restoration of SIRT1 plasma levels with recombinant murine SIRT1 for 4 weeks prevented body weight gain and improved glucose tolerance, insulin sensitivity, and vascular function in mice models of obesity and T2D. Untargeted lipidomics revealed that SIRT1 restored insulin secretory function of β-cells by reducing synthesis and accumulation of pro-apoptotic ceramides. Molecular mechanisms involved direct binding to and deacetylation of Toll-like receptor 4 (TLR4) by SIRT1 in β-cells, thereby decreasing the rate-limiting enzymes of sphingolipid synthesis SPTLC1/2 via AKT/NF-κB. Among patients with T2D, those with high baseline plasma levels of SIRT1 prior to metabolic surgery displayed restored β-cell function (HOMA2-β) and were more likely to have T2D remission during follow-up. Acetylation of TLR4 promotes β-cell dysfunction via ceramide synthesis in T2D, which is blunted by systemic SIRT1 replenishment. Hence, restoration of systemic SIRT1 may provide a novel therapeutic strategy to counteract toxic ceramide synthesis and mitigate CV complications of T2D.

Calorie Restriction Using High-Fat/Low-Carbohydrate Diet Suppresses Liver Fat Accumulation and Pancreatic Beta-Cell Dedifferentiation in Obese Diabetic Mice.

In diabetes, pancreatic β-cells gradually lose their ability to secrete insulin with disease progression. β-cell dysfunction is a contributing factor to diabetes severity. Recently, islet cell heterogeneity, exemplified by β-cell dedifferentiation and identified in diabetic animals, has attracted attention as an underlying molecular mechanism of β-cell dysfunction. Previously, we reported β-cell dedifferentiation suppression by calorie restriction, not by reducing hyperglycemia using hypoglycemic agents (including sodium-glucose cotransporter inhibitors), in an obese diabetic mice model (db/db). Here, to explore further mechanisms of the effects of food intake on β-cell function, db/db mice were fed either a high-carbohydrate/low-fat diet (db-HC) or a low-carbohydrate/high-fat diet (db-HF) using similar calorie restriction regimens. After one month of intervention, body weight reduced, and glucose intolerance improved to a similar extent in the db-HC and db-HF groups. However, β-cell dedifferentiation did not improve in the db-HC group, and β-cell mass compensatory increase occurred in this group. More prominent fat accumulation occurred in the db-HC group livers. The expression levels of genes related to lipid metabolism, mainly regulated by peroxisome proliferator-activated receptor α and γ, differed significantly between groups. In conclusion, the fat/carbohydrate ratio in food during calorie restriction in obese mice affected both liver lipid metabolism and β-cell dedifferentiation.

3,4',5-Trimethoxy-trans-stilbene ameliorates hepatic insulin resistance and oxidative stress in diabetic obese mice through insulin and Nrf2 signaling pathways.

Resveratrol has profound benefits against diabetes. However, whether its methylated derivative 3,4',5-trimethoxy-trans-stilbene (3,4',5-TMS) also plays a protective role in glucose metabolism is not characterized. We aimed to study the anti-diabetic effects of 3,4',5-TMS in vitro and in vivo. Insulin-resistant HepG2 cells (IR-HepG2) were induced by high glucose plus dexamethasone whilst six-week-old male C57BL/6J mice received a 60 kcal% fat diet for 14 weeks to establish an obese diabetic model. 3,4',5-TMS did not reduce the cell viability of IR-HepG2 cells at concentrations of 0.5 and 1 μM, which enhanced the capability of glycogen synthesis and glucose consumption in IR-HepG2 cells. Four-week oral administration of 3,4',5-TMS at 10 mg kg-1 day-1 ameliorated insulin sensitivity and glucose tolerance of diet-induced obese (DIO) mice. 3,4',5-TMS activated the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway by inhibiting phosphorylation of insulin receptor substrate (IRS)-1 at Ser307 and increasing the protein levels of IRS-1 and IRS-2 to restore the insulin signaling pathway in diabetes. 3,4',5-TMS also upregulated the phosphorylation of glycogen synthase kinase 3 beta (GSK3β) at Ser9. 3,4',5-TMS suppressed oxidative stress by increasing the protein levels of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1) and NAD(P)H : quinone oxidoreductase 1 (NQO1) and antioxidant enzyme activity. In summary, 3,4',5-TMS alleviated hepatic insulin resistance in vitro and in vivo, by the activation of the insulin signaling pathway, accomplished by the suppression of oxidative stress.

Validating the Health Benefits of Coffee Berry Pulp Extracts in Mice with High-Fat Diet-Induced Obesity and Diabetes.

The effects of coffee (Coffea arabica L.) berry pulp extracts (CBP extracts) on the improvement of diabetes, obesity, and non-alcoholic fatty liver disease (NAFLD) were evaluated using various in vitro antioxidant activity assays and through a high-fat diet-induced mild diabetic obese mouse model. After an 84-day oral administration of CBP extracts (400-100 mg/kg), bioactivities were evaluated. The in vitro analysis showed the highest DPPH● scavenging activity of 73.10 ± 4.27%, ABTS● scavenging activity of 41.18 ± 1.14%, and SOD activity of 56.24 ± 2.81%, at a CBP extract concentration of 1000 µg/mL. The in vivo analysis of the CBP extracts showed favorable and dose-dependent anti-obesity, anti-diabetic, NAFLD, nephropathy, and hyperlipidemia refinement effects through hepatic glucose enzyme activity, 5'-AMP-activated protein kinase (AMPK) up-regulation, antioxidant activity, lipid metabolism-related gene expression, and pancreatic lipid digestion enzyme modulatory activities. This study shows that an appropriate oral dosage of CBP extracts could function as a potent herbal formulation for a refinement agent or medicinal food ingredient to control type 2 diabetes and related complications.

Portulaca Oleracea L. (Purslane) Extract Protects Endothelial Function by Reducing Endoplasmic Reticulum Stress and Oxidative Stress through AMPK Activation in Diabetic Obese Mice.

Portulaca oleracea L. (purslane) is a food and a traditional drug worldwide. It exhibits anti-inflammatory, anti-oxidative, anti-tumor, and anti-diabetic bioactivities; but its activity on diabetic-associated endothelial dysfunction is unknown. This study aimed to investigate the effect of purslane on endothelial function and the underlying mechanisms. Male C57BL/6 mice had 14-week ad libitum access to a high-fat rodent diet containing 60% kcal% fat to induce obesity and diabetes whereas purslane extract (200 mg/kg/day) was administered during the last 4 weeks via intragastric gavage. Primary rat aortic endothelial cells and isolated mouse aortas were cultured with a risk factor, high glucose or tunicamycin, together with purslane extract. By ESI-QTOF-MS/MS, flavonoids and their glycoside products were identified in the purslane extract. Exposure to high glucose or tunicamycin impaired acetylcholine-induced endothelium-dependent relaxations in aortas and induced endoplasmic reticulum (ER) stress and oxidative stress with the downregulation of 5' AMP-activated protein kinase (AMPK)/ endothelial nitric oxide synthase (eNOS) signaling. Co-incubation with purslane significantly ameliorated these impairments. The effects of purslane were abolished by Compound C (AMPK inhibitor). Four-week purslane treatment ameliorated aortic relaxations, ER stress, and oxidative stress in diabetic obese mice. This study supported that purslane protected endothelial function, and inhibited ER stress and oxidative stress in vasculature through AMPK/eNOS activation, revealing its therapeutic potential against vascular complications in diabetes.

Systemic Immune Modulation Induced by Ephedrine in Obese-Diabetes (db/db) Mice.

Immune-modulatory effects in obese-diabetes (db/db) mice were observed to understand the possible mechanism(s) of ephedrine-induced unfavorable responses. The ephedrine doses were selected based on the FDA report (NTP Tech Rep Ser NO 307; CAS# 134-72-5), which showed the non-toxic dose for B6C3F1 mice. In db/db mice, higher doses (6 and 12 mg/mouse) of ephedrine significantly harmed the liver and lung morphology, including fatty liver with multiple blood vessel engorgement, alveolar wall thickening, and inflammatory response in the lung. The immune micro-environment of db/db mice was an inflammatory state with suppressed adaptive cellular immunity. After the administration of ephedrine, significant deterioration of NK activity was observed with lowered gene transcription of klrk1 encoding NKG2D, and of ccl8, a NK cell targeting chemokine. Suppressed cellular immunity in db/db mice was lowered ever further by single ephedrine treatment, as was evidenced by mitogen-induced T or B cell proliferations. These observations demonstrate that at the non-toxic doses in normal B6C3F1 mice, ephedrine clearly suppressed systemic immunity of db/db mice. The data suggest that the immune micro-environment of obese individuals is fragile and susceptible to ephedrine-related pathologic response, and this may be a prelude to the induction of obesity-related secondary immunological disorders.

Hyperfiltration can be detected by transcutaneous assessment of glomerular filtration rate in diabetic obese mice.

We addressed if hyperfiltration can be assessed transcutaneously in male diabetic obese mice (BTBRob/ob) at 12 and 24 wk and how this relates to glomerular parameters indicative for hyperfiltration. Transcutaneous assessment of FITC-Sinistrin clearance [transcutaneous assessment of glomerular filtration rate (tGFR)] was compared against classical plasma clearance. Kidney from SV620C-01-PEI perfused mice were harvested at 24 wk and processed for tissue clearing and classical histology. Perfusion patterns of glomerular capillaries, glomerular size, and vasodilation of the afferent arterioles were assessed. Although at 12 wk FITC-Sinistrin half-life (t1/2) for both tGFR and plasma clearance suggested hyperfiltration, this was not significant anymore at 24 wk. In kidneys of diabetic mice the diameter of the afferent arteriole was significantly larger and positively correlated with glomerular size. Glomerular perfusion pattern in these mice was heterogeneous ranging from non- to well-perfused glomeruli. Nonperfused glomerular areas displayed a strong periodic acid-Schiff's (PAS) positive staining. Collectively our data demonstrate that tGFR is a valid method to detect hyperfiltration. Hyperfiltration occurs early in BTBRob/ob mice and disappears with disease progression as a consequence of a reduced filtration surface. It remains to be assessed if tGFR is also a valid method in diabetic mice with severely compromised renal function.NEW & NOTEWORTHY tGFR measurement is a relatively new method to assess kidney function in conscious rodents, which can be repeated multiple times in the same animal to track the course of the disease and/or the effect of potential treatments. Since the literature was inconclusive on the suitability of this technique in obese mice, we validated it for the first time against classical plasma clearance in the commonly used BTBRob/ob mouse model.