Water Extract of Potentilla discolor Bunge Improves Hepatic Glucose Homeostasis by Regulating Gluconeogenesis and Glycogen Synthesis in High-Fat Diet and Streptozotocin-Induced Type 2 Diabetic Mice

Rapid construction of interfacial plasmonic nanoarray for SERS sensing of flavonoids

A rapid, low-cost and reliable interfacial plasmonic nanoarray is presented as surface-enhanced Raman scattering (SERS) sensing platform for preliminary quantification and identification of flavonoids. Here, CTAB-modified Au colloidal nanoparticles self-assemble at the cyclohexane/acetone-water interface to form a uniform interfacial plasmonic nanoarray. The target hydrophobic analytes including organic dye methyl red and water-insoluble flavonoids, are effectively captured at the air-water interface and enter the "hot spots" between nanoparticles during the evaporation of the oil phase, which contributes to sensitive and reproducible SERS signals. Furthermore, this remarkable SERS performance enables the quantitative determination of water-insoluble flavonoids such as kaempferol, luteolin and naringenin with low detection limits of 10-10 M, and an approximately linear correlation between SERS signals and analytical concentrations, as well as rapid multiplex analysis of flavonoids with similar structural characteristics. Additionally, directly relative content detection of crude extracts from lingonberry (Vaccinium vitis-idaea L.) is achieved on the plasmonic nanoarray, serving as a proof-of-concept demonstration for practical applications. Compared to conventional analyses of flavonoids, the proposed SERS platform circumvents complex and time-consuming pretreatments, thereby opening avenues for the analysis of oil-soluble samples and other secondary metabolites, which will facilitate widespread evaluation of quality and medical value.

Mechanisms of Action of Potentilla discolor Bunge in Type 2 Diabetes Mellitus Based on Network Pharmacology and Experimental Verification in Drosophila

Purpose

Type 2 diabetes mellitus (T2DM) is associated with reduced insulin uptake and glucose metabolic capacity. Potentilla discolor Bunge (PDB) has been used to treat T2DM; however, the fundamental biological mechanisms remain unclear. This study aimed to understand the active ingredients, potential targets, and underlying mechanisms through which PDB treats T2DM.

Methods

Components and action targets were predicted using network pharmacology and molecular docking analyses. PDB extracts were prepared and validated through pharmacological intervention in a Cg>InRK1409A diabetes Drosophila model. Network pharmacology and molecular docking analyses were used to identify the key components and core targets of PDB in the treatment of T2DM, which were subsequently verified in animal experiments.

Results

Network pharmacology analysis revealed five effective compounds made up of 107 T2DM-related therapeutic targets and seven protein-protein interaction network core molecules. Molecular docking results showed that quercetin has a strong preference for interleukin-1 beta (IL1B), IL6, RAC-alpha serine/threonine-protein kinase 1 (AKT1), and cellular tumor antigen p53; kaempferol exhibited superior binding to tumor necrosis factor and AKT1; β-sitosterol demonstrated pronounced binding to Caspase-3 (CASP3). High-performance liquid chromatography data quantified quercetin, kaempferol, and β-sitosterol at proportions of 0.030%, 0.025%, and 0.076%, respectively. The animal experiments revealed that PDB had no effect on the development, viability, or fertility of Drosophila and it ameliorated glycolipid metabolism disorders in the diabetes Cg>InRK1409A fly. Furthermore, PDB improved the body size and weight of Drosophila, suggesting its potential to alleviate insulin resistance. Moreover, PDB improved Akt phosphorylation and suppressed CASP3 activity to improve insulin resistance in Drosophila with T2DM.

Conclusion

Our findings suggest that PDB ameliorates diabetes metabolism disorders in the fly model by enhancing Akt activity and suppressing CASP3 expression. This will facilitate the development of key drug targets and a potential therapeutic strategy for the clinical treatment of T2DM and related metabolic diseases.

Scutellarin Alleviates Diabetic Retinopathy via the Suppression of Nucleotide-Binding Oligomerization Domain (NOD)-Like Receptor Pyrin Domain Containing Protein 3 Inflammasome Activation

PURPOSE

Diabetic retinopathy, a prevalent complication of diabetes, represents the leading cause of vision loss and blindness among middle-aged and elderly populations. Recent research has demonstrated the ameliorating effects of scutellarin on diabetes-associated complications such as diabetic retinopathy and type 2 diabetic cardiomyopathy. However, investigations into its protective impact and underlying mechanisms on diabetic retinopathy are scant. This study aims to explore the therapeutic potential of scutellarin in diabetic retinopathy treatment.

METHODS

Diabetic retinopathy was induced in rats through intraperitoneal injections of streptozotocin (STZ, 60 mg/kg) administered daily for three consecutive days. Following this, diabetic retinopathy rats received daily intragastric administration of scutellarin (40 mg/kg) for 42 days.

RESULTS

Our findings suggest that scutellarin alleviates histological damage in the retinal tissues of streptozotocin-challenged rats. Furthermore, scutellarin effectively enhances total retinal thickness and increases the number of ganglion cell layer (GCL) cells in the retinal tissues of streptozotocin-treated rats. Scutellarin also demonstrated anti-inflammatory and antioxidant effects in the retinal tissues of STZ-induced rats, as indicated by reduced levels of tumor necrosis factor-α, interleukin-1β, and interleukin-6, and elevated levels of glutathione peroxidase, superoxide dismutase, and catalase. Additionally, scutellarin effectively inhibited the expression of NOD-like receptor pyrin domain containing protein 3 inflammasome-related markers in the retinal tissues of streptozotocin-administered rats.

CONCLUSIONS

Collectively, our results indicate that scutellarin significantly reduces streptozotocin-induced retinal inflammation, an effect that may be partially attributed to the suppression of NLRP3 inflammasome activation.

Phytochemical profiling and neuroprotective activity of Callistemon subulatus leaves against cyclophosphamide-induced chemobrain

Cyclophosphamide (CPA) is a chemotherapeutic drug used for various types of cancers. However, patients receiving CPA for long periods suffer cognitive impairment associated with difficulties in learning, decreased concentration, and impaired memory. Chemotherapy-induced cognitive impairment, known as chemobrain, has been attributed to enhanced oxidative stress and inflammatory response. The current study aimed to identify the phytoconstituents of Callistemon subulatus extract (CSE) using HPLC-ESI/MS-MS analysis and evaluate its neuroprotective activity against CPA-induced chemobrain in rats. Fourteen compounds were identified following HPLC analysis including, five phlorglucinols, four flavonol glycosides, a triterpene, and a phenolic acid. Forty rats were divided into five groups treated for ten days as follows; group I (control group), group II received CPA (200 mg/kg, i.p.) on the 7th day, groups III and IV received CSE (200 and 400 mg/kg respectively, orally) for ten days and CPA (200 mg/kg, i.p.) on the 7th day, and group V received only CSE (400 mg/kg, orally) for ten days. The administration of CSE effectively ameliorated the deleterious effects of CPA on spatial and short-term memories, as evidenced by behavioral tests, Y-maze and passive avoidance. Such findings were further confirmed by histological examination. In addition, CSE counteracted the effect of CPA on hippocampal acetylcholinesterase (AChE) activity enhancing the level of acetylcholine. Owing to the CSE antioxidant properties, it hindered the CPA-induced redox imbalance, which is represented by decreased catalase and reduced glutathione levels, as well as enhanced lipid peroxidation. Therefore, CSE may be a promising natural candidate for protection against CPA-induced chemobrain in cancer patients.

Effects of potentilla discolor bunge extracts on oxidative stress and glycolipid metabolism in animal models of diabetes: a systematic review and meta-analysis

Background/aim: Potentilla discolor Bunge (PDB) is an ancient herb of traditional Chinese medicine. Studies have suggested that extracts of PDB may ameliorate diabetes mellitus (DM). This study aimed to systematically assess the efficacy of PDB extracts on glycolipid metabolism and oxidative stress in animal models of diabetes and to provide evidence-based references for the use of PDB extracts. Methods: This study followed the PRISMA 2020 guidelines. Studies were searched from eight databases until January 2023. Statistical analysis was performed using StataSE 15.0 and RevMan 5.3. The standard mean difference (SMD) and 95% confidence intervals (CI) were computed using the random-effects model. SYRCLE's risk of bias tool was used to assess the risk of bias. Results: In total, 32 studies with 574 animals were included. The findings demonstrated that PDB extracts considerably lowered fasting blood glucose (SMD: -3.56, 95%CI: -4.40 to -2.72, p < 0.00001); insulin resistance (SMD: -3.19, 95% CI: -5.46 to -0.92, p = 0.006), total cholesterol (SMD: -2.18, 95%CI: -2.89 to -1.46, p < 0.00001), triglyceride (SMD: -1.48, 95% CI: -2.01 to -0.96, p < 0.00001), low-density lipoprotein cholesterol (SMD: -1.80, 95% CI: -2.58 to -1.02], p < 0.00001), malondialdehyde (SMD: -3.46, 95% CI: -4.64 to -2.29, p < 0.00001) and free fatty acid levels (SMD: -3.25, 95%CI: -5.33 to -1.16, p = 0.002), meanwhile, increased insulin sensitivity index (SMD: 2.51 95% CI: 1.10 to 3.92, p = 0.0005), body weight (SMD:1.20, 95% CI: 0.38 to 2.01, p = 0.004), and the levels of high-density lipoprotein cholesterol (SMD: 1.04, 95% CI: 0.40 to 1.69, p = 0.001), superoxide dismutase (SMD:2.63, 95% CI: 1.53 to 3.73, p < 0.00001), glutathione peroxidase (SMD:1.13, 95%CI: 0.42 to1.83, p = 0.002), and catalase (SMD:0.75, 95% CI: 0.11 to 1.40], p = 0.02). Conclusion: These findings suggest that PDB extracts can ameliorate DM by improving glycolipid metabolism and oxidative stress. PDB may be a promising medication for DM; however, due to significant heterogeneity between studies, these findings should be interpreted with caution. In addition, future well-designed trials should determine which components of the PDB play a major role in ameliorating DM and whether these benefits persist in humans. Systematic Review Registration: https://www.crd.york.ac.uk/prospero, CRD42023379391.

The water extract of Potentilla discolor Bunge (PDW) ameliorates high-sugar diet-induced type II diabetes model in Drosophila melanogaster via JAK/STAT signaling

ETHNOPHARMACOLOGICAL RELEVANCE

Potentilla discolor Bunge (PD) is a member of the Rosaceae family. It has been traditionally used in folk medicine for the treatment of diabetes. Additionally, people in folk also eat fresh and tender PD stems as vegetables or brew them as tea.

AIM OF THE STUDY

The aim of this study was to explore the antidiabetic effects and underlying mechanisms of the water extract of Potentilla discolor (PDW) in a fruit fly model of high-sugar diet-induced type 2 diabetes.

MATERIALS AND METHODS

The antidiabetic efficacy of PDW was evaluated in a fruit fly model of diabetes induced by a high-sugar diet (HSD). Various physiological parameters were tested to evaluate the anti-diabetic effect of PDW. Gene expression levels related to insulin signaling pathways, glucose metabolism, lipid metabolism, and JAK/STAT signaling pathways were primarily analyzed using RT-qPCR to investigate the therapeutic mechanisms.

RESULTS

In this study, we found that the water extract of Potentilla discolor (PDW) can ameliorate type II diabetes phenotypes induced by the HSD in fruit flies. These phenotypes include growth rate, body size, hyperglycemia, glycogen metabolism, fat storage, and intestinal microflora homeostasis. PDW also improved the body size of s6k and rheb knockdown flies, suggesting its potential to activate the downstream insulin pathway and alleviate insulin resistance. Furthermore, we demonstrated that PDW reduced the expression of two target genes of the JAK/STAT signaling pathway, namely the insulin antagonist Impl2 and insulin receptor inhibitor Socs36E, which act as regulators inhibiting the activation of the insulin signaling pathway.

CONCLUSIONS

This study provides evidence for the anti-diabetic activity of PDW and suggests that its underlying mechanism may involve the improvement of insulin resistance by inhibiting the JAK/STAT signaling pathway.

Oat β-glucan ameliorates diabetes in high fat diet and streptozotocin-induced mice by regulating metabolites

Oats are widely distributed worldwide and oat β-glucan has positive effects on human health. Particularly, oat β-glucan is reported to be beneficial in the management of type 2 diabetes. The aim of the present study is to investigate the effects of oat β-glucan and its possible underlying mechanisms on diabetes in type 2 diabetic mice that was induced by streptozotocin/high-fat diet (STZ/HFD). The data indicated that oat β-glucan significantly reduced the fasting blood glucose, improved glucose tolerance, and insulin sensitivity. The results further showed that oat β-glucan remarkably decreased the levels of total cholesterol (TCHO), total triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and free fatty acids. Moreover, oat β-glucan remarkably increased the hepatic glycogen content, but largely decreased the levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in STZ/HFD-induced diabetic mice. Histological analysis showed that oat β-glucan alleviated visceral lesions. Finally, the metabolomic analysis indicated that the metabolic profile was remarkably changed after oat β-glucan intervention in diabetic mice. There were 88 and 106 differential metabolites screened as biomarkers in negative ion mode (NEG) and positive ion mode (POS) after oat β-glucan treatment, respectively. In addition, oat β-glucan significantly affected the serum metabolites of amino acids, organic acids and bile acids. Collectively, the current study elucidates oat β-glucan displays an effective nutritional intervention in diabetes.

Jiangtang Sanhao formula ameliorates skeletal muscle insulin resistance via regulating GLUT4 translocation in diabetic mice

Jiangtang Sanhao formula (JTSHF), one of the prescriptions for treating the patients with diabetes mellitus (DM) in traditional Chinese medicine clinic, has been demonstrated to effectively ameliorate the clinical symptoms of diabetic patients with overweight or hyperlipidemia. The preliminary studies demonstrated that JTSHF may enhance insulin sensitivity and improve glycolipid metabolism in obese mice. However, the action mechanism of JTSHF on skeletal muscles in diabetic mice remains unclear. To this end, high-fat diet (HFD) and streptozotocin (STZ)-induced diabetic mice were subjected to JTSHF intervention. The results revealed that JTSHF granules could reduce food and water intake, decrease body fat mass, and improve glucose tolerance, lipid metabolism, and insulin sensitivity in the skeletal muscles of diabetic mice. These effects may be linked to the stimulation of GLUT4 expression and translocation via regulating AMPKα/SIRT1/PGC-1α signaling pathway. The results may offer a novel explanation of JTSHF to prevent against diabetes and IR-related metabolic diseases.

Protective Roles of Apigenin Against Cardiometabolic Diseases: A Systematic Review

Apigenin is a flavonoid with antioxidant, anti-inflammatory, and anti-apoptotic activity. In this study, the potential effects of apigenin on cardiometabolic diseases were investigated in vivo and in vitro. Potential signaling networks in different cell types induced by apigenin were identified, suggesting that the molecular mechanisms of apigenin in cardiometabolic diseases vary with cell types. Additionally, the mechanisms of apigenin-induced biological response in different cardiometabolic diseases were analyzed, including obesity, diabetes, hypertension and cardiovascular diseases. This review provides novel insights into the potential role of apigenin in cardiometabolic diseases.

Potentilla discolor ameliorates LPS-induced inflammatory responses through suppressing NF-κB and AP-1 pathways

Potentilla discolor Bunge (PD) is a traditional Chinese medicine which has been widely used for the treatment of various inflammatory diseases (e.g., diarrhea, fever and furuncle). However, few studies focused on its effect on classical inflammation. This study aimed to investigate the anti-inflammatory effect and potential mechanism of the ethanol extract of the whole herbs of PD (EPD) in lipopolysaccharide (LPS)-induced inflammatory models. The obtained results showed that EPD decreased supernatant NO, tumor necrosis factor-α (TNF-α) and monocyte chemoattractant protein-1 (MCP-1) in LPS-activated RAW264.7 cells and mouse peritoneal macrophages. Moreover, its effect on NO was attributed to the suppression of iNOS expression rather than its activity. At the transcriptional level, EPD suppressed iNOS, TNF-α and MCP-1 mRNA expressions in LPS-stimulated RAW264.7 cells. Further study showed that EPD didn't affect the phosphorylation and degradation of IκBα, but yet impeded the nuclear translocation of p65 to inhibit NF-κB activation. Meanwhile, it also prevented JNK, ERK1/2 and p38 phosphorylation to dampen the activation of AP-1. In endotoxemia mouse model, EPD not only decreased interleukin-6, TNF-α and MCP-1 levels in serum, but also potently ameliorated diarrhea. These findings provide the theoretical basis for PD to treat inflammatory diseases, especially intestinal inflammation.

Spectrum-effect relationship between UPLC fingerprints and antidiabetic and antioxidant activities of Rosa rugosa

In this study, the antidiabetic and antioxidant properties of the chemical constituents of Rosa rugosa Thunb. (R. rugosa) was evaluated through analysis of spectrum-effect relationship. The ultra-performance liquid chromatography (UPLC) fingerprints of 21 batches of R. rugosa were evaluated by similarity analysis (SA) and hierarchical clustering analysis (HCA). The 28 common components were identified by ultra-high-performance liquid chromatography coupled to quadrupole-orbitrap high resolution mass spectrometry (UHPLC-Q-orbitrap-HRMS/MS). Meanwhile, the antidiabetic activities and antioxidant activities of 21 batches of R. rugosa were estimated in vitro. Besides, four chemometrics named principal component analysis (PCA), grey correlation analysis (GRA), partial least squares regression (PLSR) and the bivariate correlations analysis (BCA) were applied to construct spectrum-effect relationship between the UPLC fingerprints and biological activities of R. rugosa. The spectrum-effect relationship study revealed that di-O-galloyl-HHDP-glucoside, galloyl-HHDP-glucoside and avicularin were more relevant to antidiabetic activity. Di-O-galloyl-HHDP-glucoside, galloyl-HHDP-glucoside and ellagic acid were the main antioxidant components of R. rugosa. The current bioassay and spectrum-effect relationships are proper for associating sample quality with the active ingredient, and our finding would provide foundation and further understanding of the quality evaluation and quality control of R. rugosa.