Reduced Blood Glucose Research Articles

Obtusin ameliorates diabetic retinopathy by inhibiting oxidative stress and inflammation.

Diabetic retinopathy (DR) is linked to an increased risk of psychiatric and neurological conditions, largely due to chronic inflammation, oxidative stress, and microvascular damage associated with the disease. Emerging evidence suggests that Cassia seed extract has significant anti-inflammatory and antioxidant properties. However, the therapeutic potential of obtusin, a major compound in Cassia seed, and its underlying mechanisms remain unclear. This study aimed to evaluate the therapeutic efficacy of obtusin in the treatment of DR. Db/db mice were treated with obtusin (5 and 10mg/kg/day) for 12 weeks. Throughout the study, body weight, blood glucose levels, and lipid profiles were monitored. Retinal histopathology and transmission electron microscopy were used to assess the pharmacological effects of obtusin in vivo. Additionally, in vitro assays were conducted on human retinal microvascular endothelial cells cultured under high glucose conditions to explore obtusin's potential role in mitigating DR. Obtusin treatment in diabetic mice significantly reduced blood glucose levels, improved dyslipidemia, thickened retinal layers, reduced retinal oxidative stress, and inhibited the upregulation of inflammatory cytokines. It also lessened fundus microangiopathy and preserved the retina's normal barrier function. Mechanistic in vitro analysis suggested that obtusin targets the Poldip2-Nox4 oxidative stress axis and the NF-κB-MAPK-VEGFA inflammatory pathway, both of which are implicated in DR. Our findings suggest that the Poldip2-Nox4 oxidative stress axis and the NF-κB-MAPK-VEGFA inflammatory pathway could be therapeutic targets for obtusin in the treatment of DR and its associated psychiatric and neurological conditions.

Investigating the hepatoprotective and antidiabetic properties of cryogenically pulverized Turkish propolis water extracts in streptozotocin-induced diabetic rats

Diabetes is a major global health crisis, affecting millions of people worldwide and necessitating the search for effective and safe treatments, leading to various complications, including liver damage. This study investigated the hepatoprotective and antidiabetic properties of cryogenically pulverized Turkish propolis water extracts (WBTP) in streptozotocin-induced diabetic rats.Propolis samples were collected from the West Black Sea Region of Turkey and prepared as -80 °C (PP-80) and -196 °C (PP-196) water extracts. Thirty male Wistar albino rats were divided into five groups: normal control, diabetic control, diabetic + PP-80 (250 mg/kg), diabetic + PP-196 (250 mg/kg), and diabetic + metformin (250 mg/kg). After 35 days of treatment, various parameters were evaluated, including body weight, blood glucose, glycated hemoglobin (HbA1c), serum biochemistry, antioxidant enzyme activities, and histopathology of the pancreas.The results showed that WBTP extracts, especially PP-80, significantly improved body weight and reduced blood glucose and HbA1c levels. Analysis of lipid profiles revealed improvements in HDL, LDL, triglycerides, and total cholesterol levels with WBTP treatment. The antioxidant defense systems were also enhanced in the WBTP-treated groups. Histopathological examination revealed that WBTP extracts mitigated pancreatic tissue damage in the diabetic rats.In conclusion, the WBTP extracts possess hepatoprotective and antidiabetic properties, suggesting a promising avenue for further research. It emphasizes the importance of addressing both diabetes and hepatopathologies concurrently and highlights WBTP extracts as natural and potentially safer alternatives to synthetic antidiabetic drugs. Specifically, PP-80 extracts demonstrate robust effects in managing diabetes and associated liver complications in streptozotocin-induced diabetic rats, indicating their therapeutic potential.

Engineering Supramolecular Nanofiber Depots from a Glucagon-Like Peptide-1 Therapeutic.

Diabetes and obesity have emerged as major global health concerns. Glucagon-like peptide-1 (GLP-1), a natural incretin hormone, stimulates insulin production and suppresses glucagon secretion to stabilize and reduce blood glucose levels and control appetite. The therapeutic use of GLP-1 receptor agonists (e.g., semaglutide) has transformed the standard of care in recent years for treating type 2 diabetes and reversing obesity. The native GLP-1 sequence has a very short half-life, and therapeutic advances have come from molecular engineering to alter the pharmacokinetic profile of synthetic GLP-1 receptor agonists to enable once-weekly administration, reduce the frequency of injection, and improve adherence. Efforts to further extend this profile would offer additional convenience or enable entirely different treatment modalities. Here, an injectable GLP-1 receptor agonist depot is engineered through integration of a prosthetic self-assembling peptide motif to enable supramolecular nanofiber formation and hydrogelation. This supramolecular GLP-1 receptor agonistic (PA-GLP1) offers sustained release in vitro for multiple weeks, supporting long-lasting therapy. Moreover, in a rat model of type 2 diabetes, a single injection of the supramolecular PA-GLP1 formulation achieved sustained serum concentrations for at least 40 days, with an overall reduction in blood glucose levels and reduced weight gain, comparing favorably to daily injections of semaglutide. The general and modular approach is also extensible to other next-generation peptide therapies. Accordingly, the formation of supramolecular nanofiber depots offers a more convenient and long-lasting therapeutic option to manage diabetes and treat metabolic disorders.

VEGFB ameliorates insulin resistance in NAFLD via the PI3K/AKT signal pathway

BackgroundNon-alcoholic fatty liver disease (NAFLD) is one of the most universal liver diseases with complicated pathogenesis throughout the world. Insulin resistance is a leading risk factor that contributes to the development of NAFLD. Vascular endothelial growth factor B (VEGFB) was described by researchers as contributing to regulating lipid metabolic disorders. Here, we investigated VEGFB as a main target to regulate insulin resistance and metabolic syndrome.MethodsIn this study, bioinformatics, transcriptomics, morphological experiments, and molecular biology were used to explore the role of VEGFB in regulating insulin resistance in NAFLD and its molecular mechanism based on human samples, animal models, and cell models. RNA-seq was performed to analyze the signal pathways associated with VEGFB and NAFLD; Palmitic acid and High-fat diet were used to induce insulin-resistant HepG2 cells model and NAFLD animal model. Intracellular glucolipid contents, glucose uptake, hepatic and serum glucose and lipid levels were examined by Microassay and Elisa. Hematoxylin-eosin staining, Oil Red O staining, and Periodic acid-schiff staining were used to analyze the hepatic steatosis, lipid droplet, and glycogen content in the liver. Western blot and quantitative real-time fluorescent PCR were used to verify the expression levels of the VEGFB and insulin resistance-related signals PI3K/AKT pathway.ResultsWe observed that VEGFB is genetically associated with NAFLD and the PI3K/AKT signal pathway. After VEGFB knockout, glucolipids levels were increased, and glucose uptake ability was decreased in insulin-resistant HepG2 cells. Meanwhile, body weight, blood glucose, blood lipids, and hepatic glucose of NAFLD mice were increased, and hepatic glycogen, glucose tolerance, and insulin sensitivity were decreased. Moreover, VEGFB overexpression reduced glucolipids and insulin resistance levels in HepG2 cells. Specifically, VEGFB/VEGFR1 activates the PI3K/AKT signals by activating p-IRS1Ser307 expression, inhibiting p-FOXO1pS256 and p-GSK3Ser9 expressions to reduce gluconeogenesis and glycogen synthesis in the liver. Moreover, VEGFB could also enhance the expression level of GLUT2 to accelerate glucose transport and reduce blood glucose levels, maintaining glucose homeostasis.ConclusionsOur studies suggest that VEGFB could present a novel strategy for treating NAFLD as a positive factor.Graphical

A One-Week Elderberry Juice Intervention Augments the Fecal Microbiota and Suggests Improvement in Glucose Tolerance and Fat Oxidation in a Randomized Controlled Trial.

Obesity is a costly and ongoing health complication in the United States and globally. Bioactive-rich foods, especially those providing polyphenols, represent an emerging and attractive strategy to address this issue. Berry-derived anthocyanins and their metabolites are of particular interest for their bioactive effects, including weight maintenance and protection from metabolic aberrations. Earlier findings from small clinical trials suggest modulation of substrate oxidation and glucose tolerance with mediation of prospective benefits attributable to the gut microbiota, but mixed results suggest appropriate anthocyanin dosing poses a challenge. The objective of this randomized, placebo-controlled study was to determine if anthocyanin-dense elderberry juice (EBJ) reproduces glucoregulatory and substrate oxidation effects observed with other berries and if this is mediated by the gut microbiota. Overweight or obese adults (BMI > 25 kg/m2) without chronic illnesses were randomized to a 5-week crossover study protocol with two 1-week periods of twice-daily EBJ or placebo (PL) separated by a washout period. Each treatment period included 4 days of controlled feeding with a 40% fat diet to allow for comparison of measurements in fecal microbiota, meal tolerance testing (MTT), and indirect calorimetry between test beverages. Eighteen study volunteers completed the study. At the phylum level, EBJ significantly increased Firmicutes and Actinobacteria, and decreased Bacteroidetes. At the genus level, EBJ increased Faecalibacterium, Ruminococcaceae, and Bifidobacterium and decreased Bacteroides and lactic acid-producing bacteria, indicating a positive response to EBJ. Supporting the changes to the microbiota, the EBJ treatment significantly reduced blood glucose following the MTT. Fat oxidation also increased significantly both during the MTT and 30 min of moderate physical activity with the EBJ treatment. Our findings confirm the bioactivity of EBJ-sourced anthocyanins on outcomes related to gut health and obesity. Follow-up investigation is needed to confirm our findings and to test for longer durations.

Advanced deep-tissue imaging and manipulation enabled by biliverdin reductase knockout.

We developed near-infrared (NIR) photoacoustic and fluorescence probes, as well as optogenetic tools from bacteriophytochromes, and enhanced their performance using biliverdin reductase-A knock-out model (Blvra-/-). Blvra-/- elevates endogenous heme-derived biliverdin chromophore for bacteriophytochrome-derived NIR constructs. Consequently, light-controlled transcription with IsPadC-based optogenetic tool improved up to 25-fold compared to wild-type cells, with 100-fold activation in Blvra-/- neurons. In vivo , light-induced insulin production in Blvra-/- reduced blood glucose in diabetes by ∼60%, indicating high potential for optogenetic therapy. Using 3D photoacoustic, ultrasound, and two-photon fluorescence imaging, we overcame depth limitations of recording NIR probes. We achieved simultaneous photoacoustic imaging of DrBphP in neurons and super-resolution ultrasound localization microscopy of blood vessels ∼7 mm deep in the brain, with intact scalp and skull. Two-photon microscopy provided cell-level resolution of miRFP720-expressing neurons ∼2.2 mm deep. Blvra-/- significantly enhances efficacy of biliverdin-dependent NIR systems, making it promising platform for interrogation and manipulation of biological processes.

Gynostemma pentaphyllum (Thunb.) Makino Affects Autophagy and Improves Diabetic Peripheral Neuropathy Through TXNIP-Mediated PI3K/AKT/mTOR Signaling Pathway.

TXNIP is closely associated with diabetic peripheral neuropathy (DPN). Gynostemma pentaphyllum (Thunb.) Makino (GP), a perennial herb with five leaves, is considered to have medicinal values. However, it is unknown whether GP alleviates DPN by modulating TXNIP-mediated autophagy. The aim of this study was to evaluate the effect of GP on Schwann cell injury during DPN and to investigate the mechanism of GP in DPN for the first time. High-fat diet-fed GK rats and high-glucose-cultured RSC96 cells were used to establish DPN models. The effects of GP on DPN were investigated by blood glucose assay, neurological function assay, pathology assay, and immunohistochemistry. To investigate the effect of GP on autophagy and upstream PI3K/AKT/mTOR signaling pathway in Schwann cells, Western blot and immunofluorescence assay were performed on RSC96 cells to detect the expression of beclin-1 and LC3. Western blot method was used to detect the expression of PI3K, p-Akt/Akt, p-mTOR/mTOR, and RT-qPCR method and was used to detect the expression of PI3K. Apoptosis was detected by flow cytometry. The effects of TXNIP on the above indicators were also detected in RSC96 cells. Finally, the mechanism of GP regulation of autophagy and apoptosis in RSC96 cells was verified. GP reduced blood glucose level, attenuated peripheral nerve myelin damage, and improved nerve function in DPN rats. In addition, GP enhanced autophagy activity and reduced apoptosis in RSC96 cells. GP promoted autophagy by regulating TXNIP-mediated PI3K/AKT/mTOR signaling pathway, and GP reduced apoptosis in RSC96 cells by promoting cellular autophagy. GP attenuates DPN myelin damage in RSC96 cells by enhancing autophagy, and its mechanism may be related to the inhibition of PI3K/AKT/mTOR signaling pathway by up-regulating the expression of TXNIP.

Proposed mechanisms of action participating in the hypoglycemic effect of the traditionally used Croton guatemalensis Lotsy and junceic acid, its main compound.

Croton guatemalensis Lotsy (Euphorbiaceae) is an important traditional medicine that is used by the Cakchiquels of Guatemala to control hyperglycemia in patients with type 2 diabetes. Previous studies have shown that administration of this plant induces an acute hypoglycemic effect during fasting and that the main compound is junceic acid, a diterpenoid with a clerodane skeleton; however, junceic acid has not been reported to have hypoglycemic activity in the literature. As the mechanisms involved in the hypoglycemic effect of C. guatemalensis remain unknown, the objective of the present investigation was to elucidate the hypoglycemic mechanisms of this species, as well as its major compound, junceic acid. The results indicated that, similar to complete extract, junceic acid exhibited a hypoglycemic effect in hyperglycemic rats. Both C. guatemalensis extract and junceic acid inhibited the activity of two rate-limiting enzymes involved in hepatic glucose production; however, compared with chlorogenic acid, junceic acid had a more potent effect on glucose-6-phosphatase levels than chlorogenic acid, which was used as a positive control. Furthermore, both fasting and postprandial insulin levels decreased in healthy and hyperglycemic rats despite reduced blood glucose levels in both metabolic states, suggesting a potential insulin-sensitizing effect. However, neither of these compounds potentiated the effect of insulin in insulin tolerance tests nor inhibited the enzyme activity of protein tyrosine phosphatase 1B, a negative regulator of the insulin pathway. Therefore, the insulin-sensitizing effect is thought to be independent of insulin and mediated by potential activation of the AMP-activated protein kinase pathway. The specific activation of this master regulator in β-cells results in the inhibition of insulin secretion in a healthy state and the restoration of the insulin response under conditions of glucotoxicity; these effects were observed after the administration of the extract and junceic acid in healthy and hyperglycemic rats. Overall, the main findings of this study establish a basis of the mechanisms of action of C. guatemalensis and its main compound, junceic acid, in terms of their hypoglycemic effect.

Comparative Effects of Extracts from Black Rice or Pathum Rice Combined with Cereals on Blood Glucose Levels, Serum Insulin Levels and Blood Chemistry in Diabetic Rats

Rice is one of the major cereal crops in several Asian countries. It contains a variety of nutrients and provides valuable health benefits. The antidiabetic activity of rice combined with cereals has not been studied. Therefore, the present study was carried out to determine and compare the effects of extracts from Black rice (BRE), Pathum rice (PTRE), Black rice combined with cereals (BRCE), and Pathum rice combined with cereals (PTRCE) on body weight, blood glucose levels, serum insulin levels and blood chemistry of Streptozotocin (STZ)-induced diabetic rats. The results revealed that BRCE exhibited the highest activity in reducing fasting blood glucose (FBG) levels and increasing serum insulin levels, and also recovered the lipid profiles, renal function and hepatic function resulting from STZ in the diabetic rats, followed by BRE, PTRCE and PTRE, respectively. Also, BRCE exhibited an activity with similar potential to Glibenclamide. The findings indicate that the rice extracts possess antidiabetic activity which exerts the activity by increasing serum insulin resulting in reduction of blood glucose. Rice combined with cereals provides better antidiabetic activity and could be a source of valuable antidiabetic materials. HIGHLIGHTS Extracts from Black rice and Pathum Thani fragrant rice exhibit antidiabetic activity in Streptozotocin-induced diabetic rats. Antidiabetic activity of the extracts from Black rice and Pathum Thani fragrant rice is due to an increase in insulin secretion. Black rice exhibits antidiabetic activity higher than Pathum Thani fragrant rice. Combination with cereals could enhance the antidiabetic activity of rice. The extracts from Black rice and Pathum Thani fragrant rice may be useful for the management of diabetes mellitus. GRAPHICAL ABSTRACT

Anti-Hyperglycemic Effects of Thai Herbal Medicines

This study aims to investigate selected medicinal plants’ anti-oxidative and antihyperglycemic activities to develop an effective remedy for lowering blood glucose levels and/or reducing diabetes complications. Thai medicinal plants, reported to have blood sugar-lowering effects, were selected for the study: Coccinia grandis, Gymnema inodorum, Gynostemma pentaphyllum, Hibiscus sabdariffa, Momordica charantia, Morus alba, and Zingiber officinale. Each species was extracted by Soxhlet’s extraction using ethanol as solvent. The ethanolic crude extract of each species was then evaluated for its phytochemicals, anti-oxidant, and antihyperglycemic activities. The results showed that the extract of Z. officinale gave the highest values of total phenolic and total flavonoid content (167.95 mg gallic acid equivalents (GAE)/g and 81.70 mg CE/g, respectively). Anti-oxidant activity was determined using DPPH and ABTS radical scavenging activity. Among the ethanolic extracts, Z. officinale exhibited the highest anti-oxidant activity with IC50 values of 19.16 and 8.53 µg/mL, respectively. The antihyperglycemic activity was assessed using α-glucosidase inhibitory and glucose consumption activities. M. alba and G. pentaphyllum demonstrated the highest α-glucosidase inhibitory activity among the ethanolic extracts, with IC50 values of 134.40 and 329.97 µg/mL, respectively. Z. officinale and H. sabdariffa showed the highest percentage of glucose consumption activity in induced insulin-resistant HepG2 cells at a concentration of 50 µg/mL with 145.16 and 107.03%, respectively. The results from α-glucosidase inhibitory and glucose consumption activities were developed as an effective antihyperglycemic remedy. Among the remedies tested, the R1 remedy exhibited the highest potential for reducing blood glucose levels, with an IC50 value of 122.10 µg/mL. Therefore, the R1 remedy should be further studied for its effects on animals.

NSUN2 knockdown inhibits macrophage infiltration in diabetic nephropathy via reducing N5-methylcytosine methylation of SOCS1.

N5-methylcytosine (m5C) methylation is involved in various disease progression; however, its role in diabetic nephropathy (DN) has not been studied. The aim of this study was to investigate the role of NSUN2 in DN and the underlying mechanism. Streptozotocin-induced experimental mouse model was generated to analyze the role of NSUN2 in vivo, and high glucose (HG)-treated Raw264.7 cells were used to assess the effect of NSUN2 on macrophage infiltration in vitro. The regulation of NSUN2 on SOCS1 m5C methylation was evaluated using m5C methylated RNA immunoprecipitation, luciferase reporter analysis, and RNA stability determination assay. The results indicated that NSUN2 was highly expressed in the blood and kidney of DN mice. Knockdown of NSUN2 alleviated kidney damage, reduced blood glucose and urine albumin, and suppressed macrophage infiltration in DN mice. Moreover, NSUN2 interacted with SOCS1, and silenced NSUN2 inhibited m5C levels of SOCS1 to reduce SOCS1 mRNA stability. Additionally, interference with NSUN2 suppressed macrophage migration, invasion, and infiltration by positively regulating SOCS1 expression under HG conditions. In conclusion, silencing of NSUN2 inhibits macrophage infiltration by reducing m5C modification of SOCS1, and thereby attenuates renal injury. The findings suggest a novel regulatory mechanism between NSUN2-mediated m5C modification and DN.

A Comprehensive Review of Moroccan Medicinal Plants for Diabetes Management.

Moroccan flora, renowned for its diverse medicinal plant species, has long been used in traditional medicine to manage diabetes. This review synthesizes ethnobotanical surveys conducted during the last two decades. Among these plants, 10 prominent Moroccan medicinal plants are evaluated for their phytochemical composition and antidiabetic properties through both in vitro and in vivo studies. The review encompasses a comprehensive analysis of the bioactive compounds identified in these plants, including flavonoids, phenolic acids, terpenoids, and alkaloids. Phytochemical investigations revealed a broad spectrum of secondary metabolites contributing to their therapeutic efficacy. In vitro assays demonstrated the significant inhibition of key enzymes α-amylase and α-glucosidase, while in vivo studies highlighted their potential in reducing blood glucose levels and enhancing insulin secretion. Among the ten plants, notable examples include Trigonella foenum-graecum, Nigella Sativa, and Artemisia herba-alba, each showcasing distinct mechanisms of action, such as enzymatic inhibition and the modulation of glucose metabolism pathways. This review underscores the necessity for further chemical, pharmacological, and clinical research to validate the antidiabetic efficacy of these plants and their active compounds, with a view toward their potential integration into therapeutic practices.

7753 Anoctamin 4 in the Area Postrema Regulates Glucose and Energy Homeostasis

Abstract Disclosure: L. Tu: None. Y. Xu: None. Located on the floor of the 4th ventricle within the dorsal surface of the medulla oblongata, the area postrema (AP) is a circumventricular organ where a proper blood-brain barrier is missing. Numerous studies reveal that neurons in the AP are implicated into suppression of food intake (e.g., glucagon-like peptide 1 (GLP-1)-mediated anorexia), but the role of AP neurons in whole-body glucose homeostasis is less investigated. Here we identified and fully characterized the physiological functions of anoctamin-4 (Ano4, a calcium activated chloride channel)1 in the AP. CRISPR-mediated deletion of Ano4 in the AP caused a lower body weight and reduced blood glucose, concurrent with an improved glucose tolerance and increased insulin sensitivity. Chemogenetic activation of Ano4-expressing neurons in the AP (APAno4) increased food intake and blood glucose, and did not induce conditioned flavor avoidance. Both Ano4 neurons and non-Ano4 neurons (i.e., neurons do not express Ano4) sent projections to the lateral parabrachial nucleus (LPBN). Optogenetic stimulation of APAno4 ◊ LPBN circuit promoted feeding behavior and increased blood glucose, whereas stimulation of APnon-Ano4 ◊ LPBN circuit inhibited food intake and did not influence glucose homeostasis. Finally, RNAscope studies reveal that 45.7% of APAno4 neurons are glutamatergic neurons, and 41.8% of them are GABAergic neurons. Furthermore, APAno4 neurons showed only a 2.6% overlap with Glp-1r-expressing neurons in the AP, but had a 60.8% co-localization with protein tyrosine phosphatase receptor δ2, which serves as orexigenic asprosin receptor. Together, our results indicate that Ano4 neurons in the AP are the first reported orexigenic neurons, and represent potential therapeutic targets for human diseases with glucose imbalance and abnormal feeding behavior. Reference: (1) Tu, L. et al. Anoctamin 4 channel currents activate glucose-inhibited neurons in the mouse ventromedial hypothalamus during hypoglycemia. J Clin Invest 133,14. (2023). (2) Mishra, I. et al. Protein tyrosine phosphatase receptor δ serves as the orexigenic asprosin receptor. Cell Metab 34, 549-563. (2022). Presentation: 6/2/2024

9207 Anoctamin 4 in the Area Postrema Regulates Glucose and Energy Homeostasis

Abstract Disclosure: L. Tu: None. Y. Xu: None. Located on the floor of the 4th ventricle within the dorsal surface of the medulla oblongata, the area postrema (AP) is a circumventricular organ where a proper blood-brain barrier is missing. Numerous studies reveal that neurons in the AP are implicated into suppression of food intake (e.g., glucagon-like peptide 1 (GLP-1)-mediated anorexia), but the role of AP neurons in whole-body glucose homeostasis is less investigated. Here we identified and fully characterized the physiological functions of anoctamin-4 (Ano4, a calcium activated chloride channel)1 in the AP. CRISPR-mediated deletion of Ano4 in the AP caused a lower body weight and reduced blood glucose, concurrent with an improved glucose tolerance and increased insulin sensitivity. Chemogenetic activation of Ano4-expressing neurons in the AP (APAno4) increased food intake and blood glucose, and did not induce conditioned flavor avoidance. Both Ano4 neurons and non-Ano4 neurons (i.e., neurons do not express Ano4) sent projections to the lateral parabrachial nucleus (LPBN). Optogenetic stimulation of APAno4 ◊ LPBN circuit promoted feeding behavior and increased blood glucose, whereas stimulation of APnon-Ano4 ◊ LPBN circuit inhibited food intake and did not influence glucose homeostasis. Finally, RNAscope studies reveal that 45.7% of APAno4 neurons are glutamatergic neurons, and 41.8% of them are GABAergic neurons. Furthermore, APAno4 neurons showed only a 2.6% overlap with Glp-1r-expressing neurons in the AP, but had a 60.8% co-localization with protein tyrosine phosphatase receptor δ2, which serves as orexigenic asprosin receptor. Together, our results indicate that Ano4 neurons in the AP are the first reported orexigenic neurons, and represent potential therapeutic targets for human diseases with glucose imbalance and abnormal feeding behavior. Reference: (1) Tu, L. et al. Anoctamin 4 channel currents activate glucose-inhibited neurons in the mouse ventromedial hypothalamus during hypoglycemia. J Clin Invest 133,14. (2023). (2) Mishra, I. et al. Protein tyrosine phosphatase receptor δ serves as the orexigenic asprosin receptor. Cell Metab 34, 549-563. (2022). Presentation: 6/2/2024

Network pharmacology analysis revealed the mechanism and active compounds of jiao tai wan in the treatment of type 2 diabetes mellitus via SRC/PI3K/AKT signaling

Ethnopharmacological relevanceJiao-tai-wan (JTW) is a traditional Chinese herbal prescription, exerts its therapeutic effects on type 2 diabetes mellitus (T2DM). However, its mechanisms and active components remain unclear. Aim of the studyTo investigate the therapeutic mechanisms of JTW in treating type 2 diabetes mellitus (T2DM), focusing on identifying active components, their targets, and validating efficacy through SRC/PI3K/AKT signaling pathway modulation in vitro and in vivo. Materials and methodsActive ingredients were retrieved from the Traditional Chinese Medicine System Pharmacology (TCMSP) and Comprehensive Traditional Chinese Medicine Database (TCMID). Targets for these components were identified using the ChemMapper database based on 3D structural similarity. T2DM-related genes were sourced from the DisGeNET and Gene Expression Omnibus (GEO) databases. Protein-protein interaction (PPI) analysis and functional enrichment analysis were conducted to construct a pathway network of “herbs-active ingredients-candidate targets”, identifying core molecular mechanisms and key active ingredients. SwissDock was used for molecular docking to predict ligands for candidate targets. The diabetic models were established using C57BL/6 mice and human liver HepG2 cell lines. Their Effectiveness and key molecules were verified through biochemical detection and immunoblotting. ResultsTotal 30 active compounds, 597 active ingredient targets, 9631 T2DM-related genes, and 521 overlapping candidate targets were found for JTW on T2DM. Go enrichment indicated the core pathways enriched on insulin and glucose metabolism. The auto-docking demonstrated SRC has potential binds to ingredients of JTW. In vivo, JTW can reduce blood glucose, and blood lipid levels, and HOMA-IR, and increase HOMA-ISI levels in T2DM mice with reduced ALT, AST, MDA levels and increased SOD levels. Meanwhile, decreased phosphorylation of SRC, along with increased levels of phosphorylated PI3K, PI3K, and phosphorylated AKT, were observed. HE staining of liver tissues further confirmed that JTW administration improved liver morphology, reducing inflammation and necrosis. In vitro, JTW significantly ameliorates upstream dysregulation by reducing SRC phosphorylation while enhancing phosphorylated PI3K, PI3K, and AKT phosphorylation levels. ConclusionJTW may alleviate glucose, insulin resistance, and lipid metabolism disorders by the SRC/PI3K/AKT signaling pathway, that provide a novel view of potential active compounds and essential targets in treating T2DM.

Hypoglycemic activity of Garcinia mangostana L. extracts on diabetes rodent models: A systematic review and network meta-analysis.

Diabetes mellitus is a significant global health issue, and alternative treatments from natural products like Garcinia mangostana L. [Clusiaceae] or GM are being explored for their potential benefits. This study focused on evaluating the hypoglycemic effects of GM on diabetic rodent models. A comprehensive search was conducted in PubMed, Scopus, and Embase for studies reporting blood glucose levels within 2weeks as the primary outcome and changes in total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) as secondary outcomes. A network meta-analysis (NMA) was performed to determine the pooled effectiveness of each intervention, estimating the weighted mean difference (WMD) and 95% confidence interval (CI) from both direct and indirect evidence. The surface under the cumulative ranking curve (SURCA) was used to rank the interventions. Ten articles were identified, with nine included for quantitative analysis. All GM extracts showed greater effectiveness than the control in decreasing blood glucose levels within 2weeks. GM at 200mg/kg (GM200) was the top-ranked extract for reducing glucose levels beyond 2weeks and increasing HDL-C levels. The ethanol extract of GM at 200mg/kg (GME200) was the most effective for blood glucose reduction within 2weeks and for TC and TG reductions. The methanol extract of GM at 200mg/kg (GMM200) was the top-ranked extract for LDL-C reductions. GM and its extracts demonstrated significant hypoglycemic activity and improvements in lipid profiles in diabetic rodent models, highlighting their potential as therapeutic agents for the prevention and treatment of diabetes mellitus. Further research in human trials is warranted to confirm these findings and establish clinical applications. https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023426254.

Swimming Exercise Regulates Indices of Skeletal Muscle Glucose Metabolism and Attenuates Cardiac Inflammatory Cytokines Activity Via IL-6/TNF-α Pathway In Streptozotocin-Induced Diabetic Rats.

Diabetes mellitus (DM) manifests with impaired glucose metabolism that affects the musculoskeletal and cardiovascular systems. This study investigated the effects of swimming exercise on some indices of muscle glucose metabolism and cardiac inflammatory markers in diabetic rats induced with streptozotocin. Wistar rats of both sexes (150-200 g) were assigned into five groups of seven (7) rats. Group 1: Control (CON), Group 2: Diabetes only (DM), Group 3: Exercise only (EX), Group 4: Diabetes + Exercise (DM+EX), Group 5: Diabetes + Insulin (DM+IN). Type 1 DM was induced via intraperitoneal injection of streptozotocin (60 mg/kg). Insulin (6 IU/g) was administered (IP) to animals in group 5. Swimming exercise test was done for 27 days after which animals were euthanized. Blood samples were collected while hamstring muscles and heart were harvested and homogenized to assess biochemical parameters. The body weight, serum insulin level, muscle glucose metabolic indices (glycogen, Glut-4, CK-MB), and cardiac troponin-T were significantly (P<0.05) decreased. In contrast, the random blood glucose, cardiac TNF-α, and IL-6 levels were increased (P<0.05) in diabetic rats when compared with the control group. Swimming exercise regimen significantly (P<0.05) reversed these anomalies by reducing blood glucose and cardiac inflammatory cytokines (TNF-α and IL-6) levels, improving serum insulin, muscle glycogen, and GLUT-4 expression in diabetic rats when compared to the DM group. The cardiac inflammatory cytokine levels in DM+EX were comparable to the DM+IN group. In conclusion, swimming exercise improves muscle glucose metabolism and protects the heart against cardiac inflammation in diabetic conditions.

Mechanism of Yi-Qi-Bu-Shen Recipe for the Treatment of Diabetic Nephropathy Complicated with Cognitive Dysfunction Based on Network Pharmacology and Experimental Validation.

Diabetic nephropathy (DN) and cognitive dysfunction (CD) are common complications of diabetes. Yi-Qi-Bu-Shen Recipe (YQBS) can effectively reduce blood glucose, improve insulin resistance, and delay the progression of diabetic complications. The underlying mechanisms of its effects need to be further studied. This study elucidates the mechanism of YQBS in DN with CD through network pharmacology and experimental validation. Protein-protein interaction, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed. Male Sprague-Dawley (SD) rats were divided into 6 groups: model, YQBS (2, 4, 8 g/kg), positive control (metformin, 200 mg/kg), and control; the DN model was established by high sugar and high fat diet combined with intraperitoneal streptozotocin injection. After the DN model was established, the rats were gavaged for 10weeks. Serum, kidneys, and hippocampus tissues were collected to measure the expression levels of TLR4, NF-κB, TNF-α, and IL-6. The network pharmacology analysis showed that quercetin and kaempferol were the main active components of YQBS. TNF and IL-6 were the key targets, and TLR4/NF-κB pathway was crucial to YQBS in treating DN complicated with CD. Experimental validation showed that the intervention of YQBS can reduce TNF-α and IL-6 in serum, and also significantly decreases the protein expression of TLR4 and NF-κB. YQBS exerts anti-inflammatory effects on DN with CD through TLR4/NF-κB pathway. This study provides a biological basis for the scientific usage of YQBS in inflammation diseases and supplies experimental evidence for future traditional Chinese medicine development.

Cold Exposure Alleviates T2DM Through Plasma-Derived Extracellular Vesicles.

Anecdotal reports have praised the benefits of cold exposure, exemplified by activities like winter swimming and cold water immersion. Cold exposure has garnered acclaim for its potential to confer benefits and potentially alleviate diabetes. We posited that systemic cold temperature (CT, 4-8°C) likely influences the organism's blood components through ambient temperature, prompting our investigation into the effects of chronic cold exposure on type 2 diabetic (T2DM) mice and our initial exploration of how cold exposure mitigates the incidence of T2DM. The effects of CT (4-8°C) or room temperature (RT, 22-25°C) on T2DM mice were investigated. Mice blood and organ specimens were collected for fully automated biochemical testing, ELISA, HE staining, immunohistochemistry, and immunofluorescence. Glucose uptake was assessed using flow cytometry with 2-NBDG. Changes in potential signaling pathways such as protein kinase B (AKT), phosphorylated AKT (p-AKT), insulin receptor substrates 1 (IRS1), and phosphorylated IRS1 (p-IRS1) were evaluated by Western blot. CT or CT mice plasma-derived extracellular vesicles (CT-EVs) remarkably reduced blood glucose levels and improved insulin sensitivity in T2DM mice. This treatment enhanced glucose metabolism, systemic insulin sensitivity, and insulin secretion function while promoting glycogen accumulation in the liver and muscle. Additionally, CT-EVs treatment protected against the streptozocin (STZ)-induced destruction of islets in T2DM mice by inhibiting β-cell apoptosis. CT-EVs also shielded islets from destruction and increased the expression of p-IRS1 and p-AKT in adipocytes and hepatocytes. In vitro experiments further confirmed its pro-insulin sensitivity effect. Our data indicate that cold exposure may have a potentially beneficial effect on the development of T2DM, mainly through the anti-diabetic effect of plasma-derived EVs released during cold stimulation. This phenomenon could significantly contribute to understanding the lower prevalence of diabetes in colder regions.

Curcumin extract improves beta cell functions in obese patients with type 2 diabetes: a randomized controlled trial

BackgroundType 2 diabetes mellitus (T2DM) is a chronic condition characterized by insulin resistance and impaired insulin production, leading to elevated blood glucose levels. Curcumin, a polyphenolic compound from Curcuma longa, has shown potential in improving insulin sensitivity and reducing blood glucose levels, which may help mitigate type 2 diabetes progression.ObjectiveTo assess the efficacy of improving type 2 diabetes (T2DM).Study designThis randomized, double-blind, placebo-controlled trial included subjects (n = 272) with criteria for type 2 diabetes.MethodsAll subjects were randomly assigned to receive curcumin (1500 mg/day) or placebo with blind labels for 12 months. To assess the improvement of T2DM after curcumin treatments body weight and body mass index, fasting plasma glucose, glycosylated hemoglobin A1c, β-cell function (homeostasis model assessment [HOMA-β]), insulin resistance (HOMA-IR), insulin, adiponectin, and leptin were monitored at the baseline and at 3-, 6-, 9-, and 12-month visits during the course of intervention.ResultsAfter 12 months of treatment, the curcumin-treated group showed a significant decrease in fasting blood glucose (115.49 vs.130.71; P < 0.05), HbA1c (6.12 vs. 6.47; P < 0.05). In addition, the curcumin-treated group showed a better overall function of β-cells, with higher HOMA-β (136.20 vs. 105.19; P < 0.01) The curcumin-treated group showed a lower level of HOMA-IR (4.86 vs. 6.04; P < 0.001) and higher adiponectin (14.51 vs. 10.36; P < 0.001) when compared to the placebo group. The curcumin-treated group also showed a lower level of leptin (9.42 vs. 20.66; P < 0.001). Additionally, body mass index was lowered (25.9 4 vs.29.34), with a P value of 0.001.ConclusionsA 12-month curcumin intervention in type 2 diabetes patients shows a significant glucose-lowering effect. Curcumin treatment appeared to improve the overall function of β-cells and reduce both insulin resistance and body weight, with very minor adverse effects. Curcumin intervention in obese patients with type 2 diabetes may be beneficial.Trial registrationThai clinical trials regentrify no.20140303003.