Modulation of glucose transporter protein by dietary flavonoids in type 2 diabetes mellitus

Exploring flavonoid intake and all-cause mortality in diverse health conditions: Insights from NHANES 2007-2010 and 2017-2018

OBJECTIVES

Flavonoids exhibit antioxidative, anti-inflammatory, and anticancer properties, yet the relationship between flavonoid intake and all-cause mortality in the obese population remains unclear.

METHODS

This study included NHANES participants from 2007 to 2010 and 2017 to 2018. Cox regression analysis evaluated the impact of total flavonoid intake on all-cause mortality among participants with varying comorbidity profiles. Subgroup analysis was conducted by separately analyzing the six sub-classes of total flavonoids (anthocyanidins, flavan-3-ols, flavanones, flavones, flavonols, and isoflavones). Sensitivity analysis was used to investigate the impact of total flavonoid intake on all-cause mortality among patients with different comorbidities.

RESULTS

During a median follow-up period of 9.92 years (interquartile range (IQR), 5.54-14.29 years), a total of 639 participants died. COX regression analysis revealed a positive impact of flavonoid intake on all-cause mortality among participants with chronic kidney disease, with greater benefits observed in obese participants [hazard ratio (HR): 0.22, 95% CI: 0.11-0.44). In metabolically healthy obese participants (HR: 0.15, 95% CI: 0.07-0.35), obese individuals with diabetes (HR: 0.51, 95% CI: 0.29-0.88), and obese individuals with comorbid cardiovascular disease (HR: 0.37, 95% CI: 0.17-0.83), flavonoid intake was associated with a reduced risk of all-cause mortality. Restricted cubic spline (RCS) analysis indicated a non-linear relationship in obese participants, with optimal intake levels ranging from 319.4978 to 448.6907 mg/day, varying based on different comorbidity profiles. Subgroup analysis revealed varying effects of total flavonoid components in different health conditions, with hazard ratios ranging from 0.06 for higher levels of flavonol to 0.59 for higher levels of anthocyanidins in the Cox model. Sensitivity analyses further indicated that individuals with obesity and comorbid diabetes or CKD see the greatest benefit from flavonoid intake.

CONCLUSIONS

The consumption of flavonoids may be associated with a decreased risk of all-cause mortality. Consumption of flavonoids is particularly beneficial for individuals with obesity and comorbidities.

Impacts of Plu kaow (Houttuynia cordata Thunb.) Ethanolic Extract on Diabetes and Dyslipidemia in STZ Induced Diabetic Rats: Phytochemical Profiling, Cheminformatics Analyses, and Molecular Docking Studies

The increasing prevalence of diabetes and dyslipidemia poses significant health challenges, impacting millions of people globally and leading to high rates of illness and death. This study aimed to explore the potential antidiabetic and hypolipidemic effects of Plu kaow (Houttuynia cordata Thunb.) ethanolic extract (PK) in streptozotocin (STZ) induced diabetic rats, focusing on its molecular mechanisms. Diabetes was induced in fasting Long Evans rats using streptozotocin (65 mg/kg b. w.), with glibenclamide (5 mg/kg/day) used as the standard experimental drug. The treated groups received oral supplementation of PK (500 mg/kg/day) for 28 days. The study evaluated blood glucose levels, lipid status, body weight, liver, kidney, and heart function biomarkers, antioxidant activity, and histological examination of various organs. Additionally, untargeted metabolomics, cheminformatics, and molecular docking were employed to elucidate the probable mechanisms of action of PK. Based on metabolomic profiling data, the PK was found to contain various putative antidiabetic agents such as kaempferol 7-neohesperidoside, isochlorogenic acid C, rutin, datiscin, and diosmin and they have been proposed to significantly (p < 0.001) reduce blood glucose levels and modulated hyperlipidemia. PK also improved the tested liver, kidney, and heart function biomarkers and reversed damage to normal pancreatic, liver, kidney, and heart cells in histological analysis. In conclusion, PK shows promise as a potential treatment or management option for diabetes and hyperlipidemia, as well as their associated complications in diabetic rats.

Effects of kaempherol-3-rhamnoside on metabolic enzymes and AMPK in the liver tissue of STZ-induced diabetes in mice

Diabetes mellitus (DM) is a chronic metabolic disorder characterized by persistent hyperglycemia. It involves disturbances in carbohydrate, fat, and protein metabolism due to defects in insulin secretion, insulin action, or both. Novel therapeutic approaches are continuously being explored to enhance metabolic control and prevent complications associated with the disease. This study investigates the therapeutic potential of kaempherol-3-rhamnoside, a flavonoid, in managing diabetes by modulating the AMP-activated protein kinase (AMPK) pathway and improving metabolic enzyme activities in streptozotocin (STZ) -induced diabetic mice. Diabetic mice were treated with varying doses of kaempherol-3-rhamnoside and/or insulin over a 28-day period. Glycolytic and gluconeogenesis enzyme activities in the liver, fasting blood glucose levels, serum insulin levels, lipid profiles and oxidative stress markers were assessed. Treatment with kaempherol-3-rhamnoside significantly improved glycolytic enzyme activities, reduced fasting blood glucose, and enhanced insulin levels compared to diabetic controls. The compound also normalized lipid profiles and reduced oxidative stress in the liver, suggesting its potential in reversing diabetic dyslipidemia and oxidative damage. Furthermore, kaempherol-3-rhamnoside activated the AMPK pathway, indicating a mechanism through which it could exert its effects. Kaempherol-3-rhamnoside exhibits promising antidiabetic properties, potentially through AMPK pathway activation and metabolic enzyme modulation. These findings support its potential use as an adjunct therapy for diabetes management. Further clinical studies are warranted to validate these results in human subjects.

Antioxidant Mechanism, Spectroscopic and Pharmacological Properties of Four Flavonoids: DFT, Docking and Molecular Dynamics

Myricetin (1), Quercetin (2), Kaempferol (3) and Kaempferide (4) were flavonoids with phenolic hydroxyl groups. The antioxidant and pharmacological mechanisms of them were investigated in detail. The lowest hydroxyl dissociation enthalpies of 1, 2, 3 and 4 were calculated by DFT, respectively. The hydroxyl dissociation enthalpies of the four flavonoids at the O2 site are the highest. By analyzing the intramolecular hydrogen bonds and HOMO-LUMO orbitals of the four flavonoids, the reasons for their divergence of hydroxyl dissociation enthalpies and antioxidant mechanisms were further investigated. The UV-vis and IR spectra of four flavonoids were compared. The interactions about electrostatic attraction, p-π conjugation and hydrogen bond combined the flavonoid with the target protein closely. The root mean square deviation of peroxisome proliferator-activated receptor γ combined with 1, 2 and 3 increased, while that of PPARγ combined with 4 decreased.

Valuation of the significant hypoglycemic activity of black currant anthocyanin extract by both starch structure transformation and glycosidase activity inhibition

The objective of this study was to investigate the impact of anthocyanin-rich black currant extract (BCE) on the structural properties of starch and the inhibition of glycosidases, gathering data and research evidence to support the use of low glycemic index (GI) foods. The BCE induced a change in the starch crystal structure from A-type to V-type, resulting in a drop in digestibility from 81.41 % to 65.57 %. Furthermore, the inhibitory effects of BCE on glycosidases activity (α-glucosidase: IC50 = 0.13 ± 0.05 mg/mL and α-amylase: IC50 = 2.67 ± 0.16 mg/mL) by inducing a change in spatial conformation were confirmed through in vitro analysis. The presence of a 5'-OH group facilitated the interaction between anthocyanins and receptors of amylose, α-amylase, and α-glucosidase. The glycosyl moiety enhanced the affinity for amylose yet lowered the inhibitory effect on α-amylase. The in vivo analysis demonstrated that BCE resulted in a reduction of 3.96 mM·h in blood glucose levels (Area Under Curve). The significant hypoglycemic activity, particularly the decrease in postprandial blood glucose levels, highlights the potential of utilizing BCE in functional foods for preventing diabetes.

Diabetes and cancer: two epidemic diseases requiring an opposite therapeutic approach to target cells

Diabetes and cancer are two chronic metabolic diseases with ever-increasing incidence rates worldwide. These disorders can often occur together, as diabetes presents an important risk factor for cancer and some cancers could in turn lead to diabetes. In this perspective article, many more commonalities between diabetes and cancer are highlighted, including the role of lifestyle and environmental factors in the pathogenesis, the presence of a rather long latency period before clinical diagnosis of invasive disease, as well as the ultimate progression to diabetic complications or malignant metastases. Moreover, both of these devastating disorders still lack curative treatment options, whereas several currently approved antidiabetic and anticancer drugs have been originally derived from different natural sources. However, while in the case of diabetes, the main therapeutic goal is to maintain the pancreatic islet mass by preserving β-cells survival, the major purpose of cancer therapy is to kill malignant cells and reduce the neoplastic mass of solid tumors. It is expected that both diabetes and cancer, two systemic diseases with epidemic proportions, would be managed more effectively through an integral approach, considering many different aspects related to their pathogenesis, including also lifestyle changes and dietary modifications.

Metabolites of traditional Chinese medicine targeting PI3K/AKT signaling pathway for hypoglycemic effect in type 2 diabetes

Type 2 diabetes mellitus is a chronic metabolic disease characterized by insulin resistance, with high morbidity and mortality worldwide. Due to the tightly intertwined connection between the insulin resistance pathway and the PI3K/AKT signaling pathway, regulating the PI3K/AKT pathway and its associated targets is essential for hypoglycemia and the prevention of type 2 diabetes mellitus. In recent years, metabolites isolated from traditional Chinese medicine has received more attention and acceptance for its superior bioactivity, high safety, and fewer side effects. Meanwhile, numerous in vivo and in vitro studies have revealed that the metabolites present in traditional Chinese medicine possess better bioactivities in regulating the balance of glucose metabolism, ameliorating insulin resistance, and preventing type 2 diabetes mellitus via the PI3K/AKT signaling pathway. In this article, we reviewed the literature related to the metabolites of traditional Chinese medicine improving IR and possessing therapeutic potential for type 2 diabetes mellitus by targeting the PI3K/AKT signaling pathway, focusing on the hypoglycemic mechanism of the metabolites of traditional Chinese medicine in type 2 diabetes mellitus and elaborating on the significant role of the PI3K/AKT signaling pathway in type 2 diabetes mellitus. In order to provide reference for clinical prevention and treatment of type 2 diabetes mellitus.

Lactobacillus paracasei JY062 Alleviates Glucolipid Metabolism Disorders via the Adipoinsular Axis and Gut Microbiota

Glycolipid metabolic disorders (GLMD) refer to a series of metabolic disorders caused by abnormal processes of glucose and lipid synthesis, decomposition, and absorption in the body, leading to glucose and lipid excess, insulin resistance, and obesity. Probiotic intervention is a new strategy to alleviate metabolic syndrome. Lactobacillus paracasei JY062 (L. paracasei JY062) was separated from the Tibet-fermented dairy products. The results demonstrated a strong ability to relieve blood glucose disorders, blood lipid disorders, and tissue damage. The LPH group had the best effect, significantly decreasing the total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), leptin, insulin, and free fatty acid (FFA) concentrations and increasing the high-density lipoprotein cholesterol, adiponectin, and GLP-1 level compared to HFD-group mice. L. paracasei JY062 could activate the APN-AMPK pathway, increased AdipoQ, AMPK GLUT-4, and PGC-1α mRNA expression and decreased SREBP-1c, ACC, and FAS mRNA expression. L. paracasei JY062 intervention decreased the relative abundance of harmful bacteria, increased the relative abundance of beneficial bacteria, and restored the imbalance of gut microbiota homeostasis caused by a high-glucose-fat diet. L. paracasei JY062 alleviated glucolipid metabolism disorders via the adipoinsular axis and gut microbiota. This study provided a theoretical basis for probiotics to ameliorate glucolipid metabolism disorders by regulating the adipoinsular axis.

Safety evaluation of saffron extracts in early and established atherosclerotic New Zealand white rabbits

Previous research has shown that natural medications pose health risks, especially in subjects with comorbidities. This study aimed to evaluate the safety of saffron ethanolic extract (SEE) administration in early and established atherosclerotic rabbits. Rabbits were given a high-cholesterol diet (HCD) for 4 and 8 weeks to induce early and established atherosclerosis respectively, and then they were treated with 50 and 100 mg/kg/day SEE. The body weight of the animals was recorded. Blood samples were collected at baseline, pre-treatment, and post-treatment for hematological studies, lipid profiles, and biochemical profiles. Tissue specimens of the vital organs were subjected to histological examination. The above parameters were significantly altered post-intervention with 4 and 8 weeks of HCD. No significant differences in body weight were observed in all the groups post-treatment with 50 and 100mg/kg of SEE compared to pre-treatment. However, low-density lipoprotein cholesterol, total cholesterol, serum urea, and glucose significantly decreased post-treatment with 50 and 100mg/kg/day SEE compared to pre-treatment in early and established atherosclerosis groups. Hematological parameters that were affected post-intervention with HCD returned to their baseline values post-treatment with 50 and 100mg/kg/day SEE. There was a significant improvement in the vital organs post-treatment with 50 and 100mg/kg SEE. SEE can safely be administered without causing harmful effects on the hematological, biochemical profiles, and vital organs. Notably, SEE exerts hypolipidemic and hypoglycemic effects on atherosclerotic conditions. Further clinical trials are warranted to ensure the safety of saffron administration in patients with atherosclerosis-related diseases.

Icariin protects testicular damage in streptozotocin-induced diabetic rats through regulation of glycolysis pathway

OBJECTIVE

This study aims to investigate potential beneficial actions of icariin (ICA) on testicular spermatogenic function in male rats with streptozotocin (STZ)-induced diabetes and to explore the underlying mechanisms. Background: ICA was found to reduce blood glucose, regulate the endocrine function of the reproductive system, and improve testicular spermatogenic function.

METHODS

Adult rats were intraperitoneally injected with STZ (65 mg/kg) to induce type 1 diabetes mellitus (T1DM). Diabetic rats were randomly classified intoT1DM (n = 6) and T1DM + ICA (n = 6) groups. Rats without STZ and ICA treatment were assigned as control group (n = 6). The morphology of testicular tissues was examined by histological staining. The mRNA and protein expression levels were determined by quantitative real-time PCR, Western blot and immunostaining, respectively.

RESULTS

Rats from T1DM group showed a reduction in epididymis and testis weight, and a decrease in sperm count when compared to control group (p < 0.01), which was attenuated by ICA treatment (p < 0.05) Diabetic rats from T1DM group also exhibited reduced diameter and area of seminiferous tubules, along with decreased spermatogonia and primary spermatocytes number when compared to control group (p < 0.01), which was partially reversed by ICA treatment (p < 0.05) Rats from T1DM group exhibited down-regulation of PCNA mRNA and protein in the testis when compared to control group (p < 0.01); while ICA treatment up-regulated PCNA expression in the testis of diabetic rats compared to T1DM group (p < 0.05). Rats from T1DM group showed up-regulation of Bax and capase-3 and down-regulation of Bcl-2, PKM2, HK2 and lactate dehydrogenase A in the testes when compared to control group (p < 0.05), which was reversed by ICA treatment (p < 0.05).

CONCLUSION

These findings suggest that ICA may exert its protective effects on testicular damage in diabetic rats through modulation of glycolysis pathway and suppression of apoptosis.

Transmembrane behaviors and quantitative structure-activity relationship of dietary flavonoids in the presence of intestinal digestive products from different carbohydrate sources based on in vitro and in silico analysis

Bioavailability plays a key role for flavonoids to exert their bioactivities. This study investigated the transmembrane transport behavior and structure-activity of dietary flavonoids. Results showed that the apparent permeability coefficients of some flavonoids could be significantly increased when digestion products from rice flour (RD) or wheat flour (WD) are present (p < 0.05), especially in the WD, potentially due to higher reducing sugar (p < 0.05). 3D-QSAR revealed that the hydrogen bond acceptor groups at positions 5 and 6 of ring A, small-volume groups at position 3', hydrophobic groups at position 4', and large-volume groups at position 5' of ring B increased the transmembrane transport of flavonoids in the WD. A hydrogen bond donor group at position 4' of ring B enhanced the transmembrane transport of flavonoid compounds in the RD. These findings contribute to our comprehensive understanding of flavonoid absorption within the context of intestinal carbohydrate digestion.

Luteolin/ZnO nanoparticles attenuate neuroinflammation associated with diabetes via regulating MicroRNA-124 by targeting C/EBPA

OBJECTIVE

The most prevalent brain-specific microRNA, MicroRNA-124, exhibits anti-inflammatory properties. Luteolin nano-formulation with Zn oxide in the form of L/ZnO NPs may boost anti-diabetic properties; however, its beneficial effect on miRNAs is yet unknown in diabetes. The effectiveness of L/ZnONPs supplements in preventing diabetic neurodegeneration by modulating inflammatory responses in a diabetic model was investigated.

METHODS

A diabetic rat model was induced by a high-fat diet and streptozotocin (30 mg/kg I.P.). Plasma glucose, insulin, and HOMR-IR levels, as well as cytokines, lipid peroxidation, GSH/GSSG, and glucose transporter 1, were determined along with the tight junction proteins occludin (OCLN) and zona occludens 1 (ZO-1). Moreover, the expressions of brain CCAAT/enhancer-binding protein (C/EBPA mRNA), miR-124, glial fibrillary acidic protein (GFAP), and NF-kBp65 were measured alongside the histological investigation.

RESULTS

The results revealed that L/ZnO NPs were able to diminish lipid peroxidation, increase the activity of antioxidant enzymes, and reduce inflammation under oxidative stress. Consequently, it was able to reduce hyperglycemia, elevate insulin levels, and improve insulin resistance. Besides, L/ZnO NPs upregulate miR-124, reduce C/EBPA mRNA, increase BCl-2, and inhibit apoptosis. The results indicate that diabetes raises BBB permeability via tight junction protein decline, which is restored following L/ZnO NPs treatment. Luteolin/ZnO NPs regulate miR-124 and microglia polarization by targeting C/EBPA and are expected to alleviate inflammatory injury via modulation of the redox-sensitive signal transduction pathways. Luteolin/ZnO NPs have a novel target for the protection of the BBB and the prevention of neurological complications in diabetes.

Biological activities of naringenin: A narrative review based on in vitro and in vivo studies

Naringenin (4',5,7-trihydroxyflavonone) is a phytochemical mainly found in citrus fruits. It is a promising phytochemical for human health because of its beneficial effects. This review aims to present comprehensive information on naringenin biological activities along with its action mechanisms and explain the pharmacokinetic properties of naringenin. This study involves a comprehensive literature review of in vitro and in vivo studies examining the effects of naringenin. Naringenin has antidiabetic, anticancer, antimicrobial, antiobesity, gastroprotective, immunomodulator, cardioprotective, nephroprotective, and neuroprotective properties. These properties are primarily attributed to its antioxidant and anti-inflammatory activities. The most important antioxidant activities of naringenin including free radical scavenging and preventing lipid peroxidation. Naringenin can increase the concentration of antioxidant enzymes and inhibit metal chelation and various pro-oxidant enzymes. Anti-inflammatory activities of naringenin are associated with decreased mitogen-activated protein kinase activities and nuclear factor kappa B by modulating the expression and release of proinflammatory cytokine and enzymes. In vitro and in vivo studies show that naringenin has promising biological activities for a variety of diseases. More research must be conducted on the bioactivities of naringenin, and to determine its optimum dose. In addition, the efficiency of naringenin must be examined with enhanced bioavailability methods to be able to increase its therapeutic effect.

Apigetrin-enriched Pulmeria alba extract prevents assault of STZ on pancreatic β-cells and neuronal oxidative stress with concomitant attenuation of tissue damage and suppression of inflammation in the brain of diabetic rats

In the present study, in vitro, in vivo, and in silico models were used to evaluate the therapeutic potential of Pulmeria alba methanolic (PAm) extract, and we identified the major phytocompound, apigetrin. Our in vitro studies revealed dose-dependent increased glucose uptake and inhibition of α-amylase (50% inhibitory concentration (IC₅₀)= 217.19 µg/mL), antioxidant (DPPH, ferric-reducing activity of plasma (FRAP), and lipid peroxidation (LPO) [IC₅₀ = 103.23, 58.72, and 114.16 µg/mL respectively]), and anti-inflammatory potential (stabilizes human red blood cell (HRBC) membranes, and inhibits proteinase and protein denaturation [IC₅₀ = 143.73, 131.63, and 198.57 µg/mL]) by the PAm extract. In an in vivo model, PAm treatment reversed hyperglycemia and attenuated insulin deficiency in rats with streptozotocin (STZ)-induced diabetes. A post-treatment tissue analysis revealed that PAm attenuated neuronal oxidative stress, neuronal inflammation, and neuro-cognitive deficiencies. This was evidenced by increased levels of antioxidants enzymes (superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (GSH)), and decreased malondialdehyde (MDA), proinflammatory markers (cyclooxygenase 2 (COX2), nuclear factor (NF)-κB and nitric oxide (NOx)), and acetylcholinesterase (AChE) activities in the brain of PAm-treated rats compared to the STZ-induced diabetic controls. However, no treatment-related changes were observed in levels of neurotransmitters, including serotonin and dopamine. Furthermore, STZ-induced dyslipidemia and alterations in serum biochemical markers of hepatorenal dysfunction were also reversed by PAm treatment. Extract characterization identified apigetrin (retention time: 21,227 s, 30.48%, m/z: 433.15) as the major bioactive compound in the PAm extract. Consequently, we provide in silico insights into the potential of apigetrin to target AChE/COX-2/NOX/NF-κB Altogether the present study provides preclinical evidence of the therapeutic potential of the apigetrin-enriched PAm extract for treating oxidative stress and neuro-inflammation associated with diabetes.

Sub-chronic toxicity of the aqueous leaf extract of Ocimum lamiifolium Hochst. ex Benth on biochemical parameters and histopathology of liver and kidney in rats: in vivo and in- silico toxicity studies

BACKGROUND

The aerial part of Ocimum lamiifolium is commonly used in Ethiopian traditional medicine. Although this plant is mostly used in traditional medicine, its safety profile has not been documented yet. The aim of this study was to assess the sub-chronic toxicity of O. lamiifolium aqueous extract in rats and to determine the toxicity profile of GC-MS identified bioactive compounds obtained from essential oil of O. lamiifolium using in silico toxicity methods.

METHODS

Eighty rats (40 male and 40 female) were randomly assigned to four groups of ten rats per sex/group. For 90 days, Groups I-III received 200, 400, and 600 mg/kg bw of aqueous extract of O. lamiifolium, respectively. Distilled water was given to Group IV (control). Clinical observations, food intake, and rat weight were all recorded during the experiment. In addition, several biochemical parameters, organ weight, and histology of the liver and kidney were all evaluated. For the in-silico toxicity study, GC-MS identified bioactive compounds in O. lamiifolium essential oil were obtained from published articles. The compounds two-dimensional structures were constructed using Chemdraw. The two-dimensional structures were converted into a simplified molecular input line entry system (SMILES) using the Swiss ADMET web tool. Furthermore, the toxicity parameters were predicted using the ProTox II server.

RESULTS

The administration of an aqueous extract of O. lamiifolium leaves significantly (p < 0.05) reduced the test animals' food intake and body weight gain. In the high dose (600 mg/kg bw) treated group, the serum alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase levels were significantly increased (p < 0.05). In female rats given 600 mg/kg bw of O. lamiifolium, the levels of serum urea were also increased. In addition, rats given 600 mg/kg bw had significantly lower blood glucose levels than the control group (p < 0.05). Doses up to 400 mg/kg bw didn't bring a significant change to the histology of the liver. However, in the high dose (600 mg/kg bw) treated group, some female rats' livers showed mild sinusoidal and central vein dilatation, as well as parenchymal necrosis. our findings showed that all compounds derived from the essential oil of O. lamiifolium showed no mutagenicity or cytotoxicity. However, 30% of the compounds tested were hepatotoxic, 20% carcinogenic, and 20% immunotoxin.

CONCLUSION

Our findings showed that oral administration of O. lamiifoliums aqueous extract up to a dose of 400 mg/kg bw is not toxic. However, high-dose (600 mg/kg bw) significantly affected the food consumption and weight gain of the experimental rats and the serum concentration of some liver and kidney enzymes were also significantly increased. Additionally, a considerable proportion of the tested compounds were predicted to be hepatotoxic, carcinogenic and immunotoxin. Furthermore, before employing O. lamiifolium preparations as drugs, a chronic toxicity research on the essential oil as well as its components that exhibited toxicity in the in-silico toxicity study is needed. Finally, use high doses of O. lamiifolium leaves with caution.

Attenuation of hyperglycemia-associated dyslipidemic, oxidative, cognitive, and inflammatory crises via modulation of neuronal ChEs/NF-κB/COX-2/NOx, and hepatorenal functional deficits by the Tridax procumbens extract

Tridax procumbens (cotton buttons) is a flowering plant with a medicinal reputation for treating infections, wounds, diabetes, and liver and kidney diseases. The present research was conducted to evaluate the possible protective effects of the T. procumbens methanolic extract (TPME) on an experimentally induced type 2 diabetes rat model. Wistar rats with streptozotocin (STZ)-induced diabetes were randomly allocated into five groups of five animals each, viz., a normal glycemic group (I), diabetic rats receiving distilled water group (II), diabetic rats with 150 (III) and 300 mg/kg of TPME (IV) groups, and diabetic rats with 100 mg/kg metformin group (V). All treatments were administered for 21 consecutive days through oral gavage. Results: Administration of the T. procumbens extract to diabetic rats significantly restored alterations in levels of fasting blood glucose (FBG), body weight loss, serum and pancreatic insulin levels, and pancreatic histology. Furthermore, T. procumbens significantly attenuated the dyslipidemia (increased cholesterol, low-density lipoprotein-cholesterol (LDL-C), triglycerides, and high-density lipoprotein (HDL) in diabetic rats), serum biochemical alterations (alanine transaminase (ALT), aspartate transaminase (AST), alanine phosphatase (ALP), blood urea nitrogen (BUN), creatinine, uric acid, and urea) and full blood count distortion in rats with STZ-induced diabetes. The TPME also improved the antioxidant status as evidenced by increased superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), and decreased malondialdehyde (MDA); and decreased levels of cholinesterases (acetylcholinesterase (AChE) and butyrylcholinesterase (BChE)), and proinflammatory mediators including nuclear factor (NF)-κB, cyclooxygenase (COX)- 2, and nitrogen oxide (NOx) in the brain of rats with STZ-induced diabetes compared to rats with STZ-induced diabetes that received distilled water. However, TPME treatment failed to attenuate the elevated monoamine oxidases and decreased dopamine levels in the brain of rats with STZ-induced diabetes. Extract characterization by liquid chromatography mass spectrometry (LC-MS) identified isorhamnetin (retention time (RT)= 3.69 min, 8.8%), bixin (RT: 25.06 min, 4.72%), and lupeol (RT: 25.25 min, 2.88%) as the three most abundant bioactive compounds that could be responsible for the bioactivity of the plant. In conclusion, the TPME can be considered a promising alternative therapeutic option for managing diabetic complications owing to its antidiabetic, antihyperlipidemic, antioxidant, and anti-inflammatory effects in rats with STZ-prompted diabetes.

Forkhead box P3 gene polymorphisms predispose to type 2 diabetes and diabetic nephropathy in the Han Chinese populations: a genetic-association and gender-based evaluation study

BACKGROUND

Functional mutations or polymorphisms affecting forkhead box P3 (FOXP3) can lead to their abnormal FOXP3 gene expression and/or defective Treg cells generation, thus resulting in autoimmune disease and inflammatory disorders. FOXP3 also plays a key role in Type 2 diabetes mellitus (T2DM) and its complications, because the disease usually involves chronic low-grade inflammatory disorders and is associated with long-term immune system imbalance. This study aimed to investigate the association between FOXP3 polymorphisms and the susceptibility to T2DM and type 2 diabetes nephropathy (T2DN) within the Han Chinese populations.

METHODS

Polymorphisms in rs3761548C/A and rs2294021C/T were examined in 400 patients (which include an equal number of T2DM and T2DN groups) and 200 healthy controls using PCR-HRM and sequence analysis.

RESULTS

The genotype and allelic frequencies of the two single nucleotide polymorphisms (SNPs) were significantly different in T2DM and the progression of diabetes developing to T2DN. The further gender-based evaluation showed that in female subjects, rs3761548C/A was associated with an approximately 3-fold higher threat for T2DM and 4.5-fold for T2DN, while there was no noticeable association with rs2294021C/T; in males, the promoter polymorphism showed an increased predisposition of 5.4-fold and 3.4-fold predisposition to T2DM and T2DN, respectively, while rs2294021 polymorphism could impart a nearly 2-fold risk of developing T2DN. An additional analysis of combined genotypes (rs3761548 C/A-rs2294021C/T) revealed that CC-CC and CC-CT can be considered protective combinations in the predisposition of males with diabetes towards T2DN, while AA-CC and AA-TT have the opposite effect.

CONCLUSIONS

This study demonstrated the possible involvement of individual and combined genetic associations of rs3761548C/A and rs2294021C/T polymorphisms with the susceptibility to diabetes and diabetic nephropathy in the Han Chinese population, as well as gender bias.

AMPK inhibits liver gluconeogenesis: fact or fiction?

Is there a role for AMPK in the control of hepatic gluconeogenesis and could targeting AMPK in liver be a viable strategy for treating type 2 diabetes? These are frequently asked questions this review tries to answer. After describing properties of AMPK and different small-molecule AMPK activators, we briefly review the various mechanisms for controlling hepatic glucose production, mainly via gluconeogenesis. The different experimental and genetic models that have been used to draw conclusions about the role of AMPK in the control of liver gluconeogenesis are critically discussed. The effects of several anti-diabetic drugs, particularly metformin, on hepatic gluconeogenesis are also considered. We conclude that the main effect of AMPK activation pertinent to the control of hepatic gluconeogenesis is to antagonize glucagon signalling in the short-term and, in the long-term, to improve insulin sensitivity by reducing hepatic lipid content.

Therapeutic effects of icariin and icariside II on diabetes mellitus and its complications

Diabetes mellitus (DM) is a global health issue in the twenty-first century, and there are numerous challenges in preventing and alleviating its chronic complications. The herb Epimedium has beneficial therapeutic effects on various human diseases, including DM. Its major flavonoid component, icariin, has significant anti-DM activity and may help improve pancreatic β-cell dysfunction and insulin resistance. Furthermore, preclinical evidence has shown that icariin and its in vivo bioactive form, icariside II, have preventive and therapeutic effects on several diabetic complications, including diabetic cardiomyopathy, diabetic vascular endothelial disorder, diabetic nephropathy, and diabetic erectile dysfunction. In this review, we present the general and toxicological information concerning icariin and icariside II and review the anti-DM effects of icariin from a molecular perspective. Additionally, we discuss the potential benefits of icariin and icariside II on the important pathological mechanisms of various diabetic complications. Despite positive preclinical evidence, additional investigations are needed before relevant clinical studies can be conducted. Therefore, we conclude with suggestions for future research. Hopefully, this review will provide a comprehensive molecular perspective for future research and product development related to icariin and icariside II in treating DM and diabetic complications.

Ethnopharmacology, phytochemistry and pharmacology of Benincasae Exocarpium: A review

Benincasae Exocarpium (BE, Dongguapi in Chinese), as the dried outer pericarp of Benincasa hispida (wax gourd) in Cucurbitaceae family, is one of traditional Chinese medicines with the same origin as medicine and food. Up to now, 43 compounds were isolated from BE, including flavonoids, alkaloids, tannins, phenolic acids, soluble fiber and carbohydrates. Modern pharmacological studies and clinical practice showed that BE has diuretic, hypolipidemic effects, hypoglycemic, antioxidant, antibacterial, and other effects. The folk uses, functional factors, pharmacological activities, patents and clinical applications of BE were reviewed in this paper. In addition, the paper also discussed the current problems for the further studies. The information summarized in this paper provides valuable clues for the comprehensive utilization of medicine and food resources and gives a scientific basis for the development of medicinal plants of BE.

Effect of Tithonia diversifolia Leaf Extract on Leptin, Adiponectin, and Insulin Receptor Levels in Diabetic Rats

This study aimed to evaluate the effect of Tithonia diversifolia extract (TDE) on leptin, adiponectin, and insulin receptor (IR) concentrations in diabetic rats. Twenty-four Wistar rats were divided into a control and treatment groups (n=6 per group). The control group received normal saline, and the treatment groups received 0.25% sodium carboxymethyl cellulose, TDE at 100 mg/kg body weight (bw), and catechin at 10 mg/kg bw for 7 days. On day 8, the rats were sacrificed, blood samples were obtained, and leptin, adiponectin, and insulin concentrations were measured using avidinhorseradish peroxidase sandwich-enzyme-linked immunosorbent assay. A calorimetric method was used to measure blood glucose (BG) and total serum cholesterol concentrations. The pancreas and kidneys were collected for the measurement of renal IR and macrophage cluster of differentiation (CD)14 levels using immunohistochemical staining. Acute type 2 diabetes mellitus (T2DM) with elevated BG and total serum cholesterol concentrations was observed in the treatment groups administered streptozotocin. The administration of TDE at 100 mg/kg bw significantly decreased leptin and increased adiponectin concentrations (P≤0.05). Furthermore, TDE treatment significantly increased renal IR and decreased macrophage CD14 levels (P<0.05). Therefore, TDE decreased leptin and BG concentrations by increasing IR levels. TDE also suppressed the necrosis of pancreatic tissues by inhibiting macrophage CD14 expression in diabetic rats. However, further research is necessary to determine the effect of TDE on interleukin and IR levels in the related tissues of patients with T2DM.

Therapeutic potential of mangiferin against kidney disorders and its mechanism of action: A review

There is a swing in research developments concerning the utilization of natural products as effective pharmacotherapeutic agents due to their comparatively lower toxicities than synthetic compounds. Among natural products, mangiferin is a natural C-glucosyl xanthonoid polyphenol with remarkable pharmacological activities. Emerging evidence indicates the therapeutic benefits of mangiferin against various kidney disorders, including renal injury, diabetic nephropathy, renal fibrosis, hyperuricemic nephropathy, and lupus nephritis, in experimental animal models. The mangiferin induced antioxidant response resulting in vital functions, such as protection against renal inflammation, inhibits renal cell apoptosis, activates autophagy, causes immunomodulation, regulates renal urate transporters and modulates cell signalling pathways. The purpose of this review provide a brief overview of the in vitro/in vivo reno-protective effect of mangiferin and the underlying mechanism(s) in protecting against kidney disorders. Understanding the pharmacological actions of mangiferin is prominence due to its excellent therapeutic potential in managing kidney disorders. Thus, in addition to this review, in-silico molecular docking is performed against nuclear factor kappa B (NF-κB) and soluble epoxide hydrolase (sEH) to study the mechanism of action of mangiferin. It is believed that mangiferin is a safe reno-protective molecule. The observed positive effects are attributed to the inhibition of inflammation caused by NF-κB and sEH upregulation and oxidative stress activation. Studies on the efficacy and safety of mangiferin in clinical trials are further warranted to confirm its medicinal potential as therapeutic agent for kidney disorders in humans.

Dietary supplementation of inulin alleviates metabolism disorders in gestational diabetes mellitus mice via RENT/AKT/IRS/GLUT4 pathway

BACKGROUND

Gestational diabetes mellitus (GDM) has significant short and long-term health consequences for both the mother and child. There is limited but suggestive evidence that inulin could improve glucose tolerance during pregnancy. This study assessed the effect of inulin on glucose homeostasis and elucidated the molecular mechanisms underlying the inulin-induced antidiabetic effects during pregnancy.

METHOD

Female C57BL/6 mice were randomized to receive either no treatment, high-dose inulin and low-dose inulin for 7 weeks with measurement of biochemical profiles. A real-time² (RT²) profiler polymerase chain reaction (PCR) array involved in glycolipid metabolism was measured.

RESULTS

Inulin treatment facilitated glucose homeostasis in a dose-dependent manner by decreasing fasting blood glucose, advanced glycation end products and total cholesterol, and improving glucose tolerance. Suppressing resistin (RETN) expression was observed in the inulin treatment group and the expression was significantly correlated with fasting blood glucose levels. The ratios of p-IRS to IRS and p-Akt to Akt in liver tissue and the ratio of p-Akt to Akt in adipose tissue as well as the expression level of GLUT4 increased significantly after inulin treatment.

CONCLUSIONS

Our findings indicated improvement of glucose and lipid metabolism by inulin was to activate glucose transport through the translocation of GLUT4 which was mediated by insulin signaling pathway repairment due to decreased expression of RETN and enhanced phosphorylation of IRS and Akt in GDM mice.

Effects of polyphenols in aging and neurodegeneration associated with oxidative stress

Aging is defined as the functional loss of tissues and organs over time. This is a biological, irreversible, progressive, and universal process that results from genetic and environmental factors, such as diet, physical activity, smoking, harmful alcohol consumption, and exposure to toxins, among others. Aging is a consequence of molecular and cellular damage built up over time. This damage begins with a gradual decrease in physical and mental capacity, thus increasing the risk of neurodegenerative diseases such as Alzheimer's and Parkinson's disease. Neuronal, functional, and structural damage can be explained by an imbalance among free radicals, reactive oxygen species, reactive nitrogen species, and antioxidants, which finally lead to oxidative stress. Due to the key role of free radicals, reactive oxygen species, and reactive nitrogen species, antioxidant therapy may reduce the oxidative damage associated with neurodegeneration. Exogenous antioxidants are molecules that may help maintain the balance between the formation and elimination of free radicals, thus protecting the cell from their toxicity. Among them, polyphenols are a broad group of secondary plant metabolites with potent antioxidant properties. Here, we review several studies that show the potential role of polyphenol consumption to prevent, or slow down, harmful oxidative processes linked to neurodegenerative disorders.

Effects and mechanisms of tea on obesity

Obesity has become a global health concern. It increases the risk of several diseases, such as type 2 diabetes mellitus, nonalcoholic fatty liver disease, and certain cancers, which threatens human health and increases social economic burden. As one of the most consumed beverages, tea contains various phytochemicals with potent bioactive properties and health-promoting effects, such as antioxidant, immune-regulation, cardiovascular protection and anticancer. Tea and its components are also considered as potential candidates for anti-obesity. Epidemiological studies indicate that regular consumption of tea is beneficial for reducing body fat. In addition, the experimental studies demonstrate that the potential anti-obesity mechanisms of tea are mainly involved in increasing energy expenditure and lipid catabolism, decreasing nutrient digestion and absorption as well as lipid synthesis, and regulating adipocytes, neuroendocrine system and gut microbiota. Moreover, most of clinical studies illustrate that the intake of green tea could reduce body weight and alleviate the obesity. In this review, we focus on the effect of tea and its components on obesity from epidemiological, experimental, and clinical studies, and discuss their potential mechanisms.

Hepatoprotective effects of flavonoids from common buckwheat hulls in type 2 diabetic rats and HepG2 cells

Flavonoids from common buckwheat hulls (BHFs) show significant antioxidant and antidiabetic potential. However, their hepatoprotective property is yet to be defined. This study aims to examine the hepatoprotective effect of BHFs in type 2 diabetes mellitus (T2DM) rats and chronic high glucose-damaged HepG2 cells. Results showed that BHF treatment significantly relieves the state of insulin resistance, thereby reducing blood glucose and improving oxidative stress in T2DM rats. It is worth mentioning that BHF treatment improved diabetes-induced liver damage disorders, manifested as the clearance of liver fat and the decline of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities. In vitro, HepG2 cells pretreated with BHFs maintained higher superoxide dismutase (SOD), glutathione peroxidase (GSH-px), and catalase (CAT) activities than the unprotected group. In parallel, compared with the unprotected group, BHFs significantly reduced the leakage of ALT and AST in pre-protected group dose-dependently. These results indicated that BHFs had considerable antioxidant and hepatoprotective potential and could be promising to be used as nutraceuticals and dietary supplements to prevent and/or protect against liver disorders.

Green Tea from the Far East to the Drug Store: Focus on the Beneficial Cardiovascular Effects

Cardiovascular diseases (CVD) are the leading cause of death worldwide. Evidence from observational and randomized controlled studies showing the potential benefits of green tea on lowering CVD risk has been emerging rapidly during the past few decades. These benefits include reduced risk for major cardiovascular events, lowering of blood pressure, decreased LDL cholesterol levels and weight loss. At the same time, the understanding of the physiological mechanisms behind these alterations is advancing. Consumption of green tea originated from China thousands of years ago, but since then, it expanded all over the world. Recent advances in understanding the role of tea polyphenols, mainly catechins, as mediators of tea's health benefits, have caused the emergence of various types of green tea extracts (GTE) on the market. While taking green tea is generally considered safe, there are concerns about the safety of using tea extracts. The present article reviews the current evidence of green tea consumption leading to reduced CVD risk, its potential biological mechanisms and the safety of using GTE.

A study on toxicity and anti-hyperglycemic effects of Abhrak Bhasma in rats

Background

Abhrak bhasma (AB) is widely used in the treatment of diabetes mellitus (DM); however, no scientific study is reported till date on its efficacy and safety to prove it's pharmacological effects. Streptozotocin (STZ) is a gulcosamine–nitrosourea complex produced by Streptomyces achromogenes, which particularly induces DNA strand breakage in pancreatic β-cells causing DM. The damage caused by STZ to pancreatic β-cells is coupled with insulin release in the initial stage, subsequently leading to hyperglycemia owing to insulin deficiency.

Objective(s)

In the present study, the safety and effectiveness of AB was evaluated by invivo acute and sub-acute toxicity study and STZ-induced hyperglycemic activity in rats.

Materials and methods

Acute oral toxicity assessed as per OECD 425 guidelines by employing up-down procedure (UDP), sub-acute toxicity as per OECD-407 guidelines and anti-hyperglycemic activity using STZ method. The anti-hyperglycemic potential of AB in rats (40, 80, and 160 mg/kg body weight (b.w.)) was evaluated by determining the body weight, blood glucose, organ weight, lipid profile, and histo-morphological and histo-pathological investigations.

Results

The highest tolerated dose of AB was 2000 mg/kg b.w., and sub-acute toxicity of different AB doses showed no significant variation, when compared with the control. Interestingly, a noteworthy reduction in blood glucose, total cholesterol, and triglycerides levels were observed in AB-treated diabetic rats, along with a considerable increase in body weight, when compared with those noted in the disease control and normal control.

Conclusion

Effectiveness of AB as a potential safe and potent candidate for the treatment of diabetes was revealed as compared to the standard drug Metformin by STZ-induced method.

Stimulatory effect of docosahexaenoic acid alone or loaded in zinc oxide or silver nanoparticles on the expression of glucose transport pathway

The role of glucose transporters (GLUTs) in diabetes mellitus has become more prominent as a possible therapeutic target. In the present study, we aimed to compare the effect of zinc oxide nanoparticles (ZnONPs), silver nanoparticles (AgNPs), and docosahexaenoic acid (DHA) alone or loaded in ZnONPs or AgNPs on insulin signaling pathway and GLUTs expression in diabetic rats. In the experimental part, rats were divided into seven groups; control, diabetic, and the other five groups were diabetic received different treatments. Fasting blood sugar (FBS), serum level of insulin, insulin resistance (IR), and serum level of phosphatidylinositol 3-kinase (PI3K) were evaluated. In addition, insulin expression in pancreatic islets was assessed by immunohistochemical analysis, and the expression of liver GLUTs 1, 2, and 4 and liver insulin receptor substrate-1 (IRS-1) was evaluated by real-time polymerase chain reactions (RT-PCR). The results of the current study showed that ZnONPs, AgNPs, and DHA alone or loaded in ZnONPs or AgNPs attenuated levels of FBS, insulin and decreased IR in diabetic rats through enhancing the expression of GLUTs as well as IRS-1 and PI3K. Furthermore, AgNPs loaded with DHA showed the most significance with high comparability to the control group. In conclusion, this study elucidated the role of GLUTs and IRS-1 in diabetes and introduced novel characteristics of ZnONPs, AgNPs, and DHA alone or loaded in ZnONPs or AgNPs as a therapeutic modality to activate GLUTs and IRS1, which may be beneficial for diabetic patients with IR.

Uncurtaining the pivotal role of ABC transporters in diabetes mellitus

The metabolic disorders are the edge points for the initiation of various diseases. These disorders comprised of several diseases including diabetes, obesity, and cardiovascular complications. Worldwide, the prevalence of these disorders is increasing day by day. The world's population is at higher threat of developing metabolic disease, especially diabetes. Therefore, there is an impregnable necessity of searching for a newer therapeutic target to reduce the burden of these disorders. Diabetes mellitus (DM) is marked with the dysregulated insulin secretion and resistance. The lipid and glucose transporters portray a pivotal role in the metabolism and transport of both of these. The excess production of lipid and glucose and decreased clearance of these leads to the emergence of DM. The ATP-binding cassette transporters (ABCT) are important for the metabolism of glucose and lipid. Various studies suggest the key involvement of ABCT in the pathologic process of different diseases. In addition, the involvement of other pathways, including IGF signaling, P13-Akt/PKC/MAPK signaling, and GLP-1 via regulation of ABCT, may help develop new treatment strategies to cope with insulin resistance dysregulated glucose metabolism, key features in DM.

Annona muricata L. extract decreases intestinal glucose absorption and improves glucose tolerance in normal and diabetic rats

Introduction: Poorly controlled hyperglycemia causes numerous health complications. Postprandial hyperglycemia is an important indicator of diabetic status. The aim of this research was to evaluate the effect of Annona muricata L. extract on the in vitro intestinal glucose absorption in diabetic rats and in vivo antihyperglycemic activity in both normal and diabetic rats. Methods: Phytochemical screening of the aqueous extract from the leaves of A. muricata was carried out. Albino rats were randomly assigned into normal and diabetic groups. Each group was divided into three subgroups: control (vehicle), experimental (A. muricata), and standard (Metformin) groups, to determine antihyperglycemic activity at different times after glucose overload. The everted intestinal sac technique was used to study intestinal glucose absorption in diabetic rats. Results: Aqueous leaf extract of Peruvian A. muricata exhibited statistically significant (P < 0.05) in vivo antihyperglycemic activity in both normal and diabetic rats when compared to the control group. The magnitude of the effect was similar to metformin treatment. Moreover, the aqueous leaf extract of A. muricata significantly diminished in vitro intestinal glucose absorption, with a magnitude similar to metformin treatment. Phytochemical analysis of the aqueous extract revealed the presence of tannins, flavonoids, alkaloids, and leucoanthocyanidins, among others. Conclusion: This study reveals that A. muricata aqueous extract is able to reduce in vitro intestinal glucose absorption and improve oral glucose tolerance in rats.

Identification of new GLUT2-selective inhibitors through in silico ligand screening and validation in eukaryotic expression systems

Glucose is an essential energy source for cells. In humans, its passive diffusion through the cell membrane is facilitated by members of the glucose transporter family (GLUT, SLC2 gene family). GLUT2 transports both glucose and fructose with low affinity and plays a critical role in glucose sensing mechanisms. Alterations in the function or expression of GLUT2 are involved in the Fanconi-Bickel syndrome, diabetes, and cancer. Distinguishing GLUT2 transport in tissues where other GLUTs coexist is challenging due to the low affinity of GLUT2 for glucose and fructose and the scarcity of GLUT-specific modulators. By combining in silico ligand screening of an inward-facing conformation model of GLUT2 and glucose uptake assays in a hexose transporter-deficient yeast strain, in which the GLUT1-5 can be expressed individually, we identified eleven new GLUT2 inhibitors (IC₅₀ ranging from 0.61 to 19.3 µM). Among them, nine were GLUT2-selective, one inhibited GLUT1-4 (pan-Class I GLUT inhibitor), and another inhibited GLUT5 only. All these inhibitors dock to the substrate cavity periphery, close to the large cytosolic loop connecting the two transporter halves, outside the substrate-binding site. The GLUT2 inhibitors described here have various applications; GLUT2-specific inhibitors can serve as tools to examine the pathophysiological role of GLUT2 relative to other GLUTs, the pan-Class I GLUT inhibitor can block glucose entry in cancer cells, and the GLUT2/GLUT5 inhibitor can reduce the intestinal absorption of fructose to combat the harmful effects of a high-fructose diet.

Caralluma europaea (Guss) N.E.Br.: A review on ethnomedicinal uses, phytochemistry, pharmacological activities, and toxicology

ETHNOPHARMACOLOGICAL RELEVANCE

Caralluma europaea (Guss) N.E.Br. (Apocynaceae), is a medicinal plant distributed in Morocco, Algeria, Tunisia, Libya, Egypt, Jordan, Spain, and Italy. The different parts of the plant are used traditionally to treat various diseases such as diabetes mellitus, flu, caught, kidney stones, cysts, respiratory infection, cancer, digestives disorders, urogenital infections, metabolic disorders, and cardiovascular problems.

AIM OF THE REVIEW

In this review, previous reports on C. europaea concerning its morphological description, geographical distribution, ethnomedicinal uses, phytochemistry, pharmacological properties, and toxicological studies were critically summarized.

MATERIALS AND METHODS

A systematic review of the literature on C. europaea was performed by searching the scientific databases Science Direct, PubMed, Scopus, and Google Scholar.

RESULTS

In traditional medicine, C. europaea used to treat several illnesses including diabetes, cancer, and kidney stones. Our analysis of the previous reports confirmed the scientific evidence of C. europaea ethnomedicinal uses, especially the antidiabetic activity. However, there was no clear correlation between previous pharmacological reports on C. europaea and its other ethnomedicinal uses in the treatment of kidney stones, flu, caught, metabolic, digestive, cardiovascular and respiratory disorders. The essential oils and extracts of C. europaea exhibited several in vitro and in vivo pharmacological properties such as antidiabetic, antioxidant, anti-inflammatory, analgesic, anti-proliferative, antibacterial, antimicrobial, toxicological, and immunomodulatory effects. Phytochemical characterization of C. europaea revealed the presence of several classes of secondary metabolites such as terpenoids, polyphenols, and flavonoids compounds. Finally, the food preservative ability of the extracts and essential oil obtained from C. europaea has been fully discussed.

CONCLUSION

Ethnomedicinal surveys indicated the use of C. europaea for the treatment of numerous diseases. Pharmacological reports showed that C. europaea exhibited significant antidiabetic, antioxidant, anti-inflammatory, analgesic, anti-proliferative, antibacterial, antimicrobial, and immunomodulatory effects. Further studies on the phytochemistry of bioactive compounds should be performed by using bioactivity-guided isolation strategy and improve their biological potency as well as scientific exploitation of traditional uses. An in-depth investigation is needed to valid the food preservative properties.

Naringenin Attenuates Non-Alcoholic Fatty Liver Disease by Enhancing Energy Expenditure and Regulating Autophagy via AMPK

Background: The prevalence of non-alcoholic fatty liver disease (NAFLD) keeps growing recently. Purpose: To investigate the effects and mechanisms of naringenin (NAR) on NAFLD. Methods: High-fat diet (HFD)-induced NAFLD rats were orally administered with NAR at 10, 30, and 90 mg/kg for 2 weeks. The serum level of triglyceride (TG), total cholesterol (TC), glutamic-oxaloacetic transaminase (AST), and glutamic-pyruvic transaminase (ALT) was measured. The hepatic histology was detected by H&E and oil red O staining. L02 and Huh-7 cells were induced by sodium oleate to establish a NAFLD cell model. The effects of NAR on lipid accumulation were detected by oil red O staining. The glucose uptake and ATP content of 3T3-L1 adipocytes and C2C12 myotubes were measured. The expression of proteins of the AMPK signaling pathway in 3T3-L1 adipocytes and C2C12 myotubes was assessed by Western blotting. The mitochondrial biogenesis of 3T3-L1 adipocytes and C2C12 myotubes was measured by mitotracker orange staining and Western blotting. The biomarkers of autophagy were detected by Western blotting and immunofluorescence. The binding of NAR to AMPKγ1 was analyzed by molecular docking. Chloroquine and compound C were employed to block autophagic flux and AMPK, respectively. Results: NAR alleviated HFD-induced NAFLD in rats at 10, 30, and 90 mg/kg. NAR attenuated lipid accumulation in L02 and Huh-7 cells at 0.7, 2.2, 6.7, and 20 μM. NAR increased glucose uptake, decreased the ATP content, activated the CaMKKβ/AMPK/ACC pathway, and enhanced the mitochondrial biogenesis in 3T3-L1 adipocytes and C2C12 myotubes. NAR increased autophagy and promoted the initiation of autophagic flux in 3T3-L1 preadipocytes and C2C12 myoblasts, while it inhibited autophagy in NAFLD rats, 3T3-L1 adipocytes, and C2C12 myotubes. Molecular docking showed that NAR binds to AMPKγ1. Compound C blocked effects of NAR on lipid accumulation and autophagy in L02 cells. Conclusion: NAR alleviates NAFLD by increasing energy expenditure and regulating autophagy via activating AMPK directly and indirectly. The direct binding of NAR and AMPKγ1 needs further validation.

Oat-Based Foods: Chemical Constituents, Glycemic Index, and the Effect of Processing

The desire for foods with lower glycemic indices has led to the exploration of functional ingredients and novel food processing techniques. The glycemic index (GI) is a well-recognized tool to assess the capacity of foods to raise blood glucose levels. Among cereal crops, oats have shown the greatest promise for mitigating glycemic response. This review evaluated decades of research on the effects of oat components on the GI level of oat-based foods with specific emphasis on oat starch, β-glucans, proteins, and phenolics. The effects of commonly used processing techniques in oats on GI level, including heating, cooling, and germination were also discussed. In addition, the GI of oat-based foods in various physical formats such as whole grain, flakes, and flour was systematically summarized. The aim of this review was to synthesize knowledge of the field and to provide a deeper understanding of how the chemical composition and processing of oats affect GI, thereby further benefiting the development of low-GI oat foods.

Morin alleviates fructose-induced metabolic syndrome in rats via ameliorating oxidative stress, inflammatory and fibrotic markers

Metabolic syndrome (MBS) is a widespread disease that has strongly related to unhealthy diet and low physical activity, which initiate more serious conditions such as obesity, cardiovascular diseases and type 2 diabetes mellitus. This study aimed to examine the therapeutic effects of morin, as one of the flavonoids constituents, which widely exists in many herbs and fruits, against some metabolic and hepatic manifestations observed in MBS rats and the feasible related mechanisms. MBS was induced in rats by high fructose diet feeding for 12 weeks. Morin (30 mg/kg) was administered orally to both normal and MBS rats for 4 weeks. Liver tissues were used for determination of liver index, hepatic expression of glucose transporter 2 (GLUT2) as well as both inflammatory and fibrotic markers. The fat/muscle ratio, metabolic parameters, systolic blood pressure, and oxidative stress markers were also determined. Our data confirmed that the administration of morin in fructose diet rats significantly reduced the elevated systolic blood pressure. The altered levels of metabolic parameters such as blood glucose, serum insulin, serum lipid profile, and oxidative stress markers were also reversed approximately to the normal values. In addition, morin treatment decreased liver index, serum liver enzyme activities, and fat/muscle ratio. Furthermore, morin relatively up-regulated GLUT2 expression, however, down-regulated NF-κB, TNF-α, and TGF-β expressions in the hepatic tissues. Here, we revealed that morin has an exquisite effect against metabolic disorders in the experimental model through, at least in part, antioxidant, anti-inflammatory, and anti-fibrotic mechanisms.

A multi-targeting strategy to ameliorate high-fat-diet- and fructose-induced (western diet-induced) non-alcoholic fatty liver disease (NAFLD) with supplementation of a mixture of legume ethanol extracts

NAFLD (non-alcoholic fatty liver disease) is a multifactorial liver disease related to multiple causes or unhealthy conditions, including obesity and chronic inflammation. The accumulation of excess triglycerides, called steatosis, is known as a hallmark of an imbalance between the rates of hepatic fatty acid uptake/synthesis and oxidation/export. Furthermore, occurrence of NAFLD may lead to a cocktail of disease consequences caused by the altered metabolism of glucose, lipids, and lipoproteins, for instance, insulin resistance, type II diabetes, nonalcoholic steatohepatitis (NASH), liver fibrosis, and even hepatocarcinogenesis. Due to the complexity of the occurrence of NAFLD, a multi-targeting strategy is highly recommended to effectively address the issue and combat the causal loop. Ethanol extracts of legumes are popular supplements due to their richness and diversity in phytochemicals, especially isoflavones and anthocyanins. Although many of them have been reported to have efficacy in the treatment of different metabolic syndromes and obesity, there have not been many studies on them as a supplemental mixture. In this study, the alleviative effects of selected legume ethanol extracts (CrE) on high-fat-diet- and fructose-induced obesity, liver steatosis, and hyperglycemia are discussed. As revealed by the findings, CrE not only ameliorated obesity in terms of weight gained and enlargement of adipose tissue, but also significantly reduced the incidence of steatosis via phosphorylation of AMPK, resulting in inhibition of the downstream SREBP-1c/FAS pathway and an increase in an indicator of β-oxidation (carnitine palmitoyl transferase 1a, CPT1A). Furthermore, CrE dramatically alleviated inflammatory responses, including both plasma and hepatic TNF-α, IL-6, and MCP-1 levels. CrE also had attenuating effects on hyperglycemia and insulin resistance and significantly reduced the fasting glucose level, fasting insulin level, and plasma leptin, and it exhibited positive effects in the Oral glucose tolerance test (OGTT) and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR). At the molecular level, CrE could activate the PI3K/Akt/Glut2 pathway, which indicated an increase in insulin sensitivity and glucose uptake. Taken together, these results suggest that ethanol extracts of legumes could be potential supplements for metabolic syndromes, and their efficacy and effectiveness might facilitate the multi-targeting strategy required to mitigate NAFLD.

Sub-chronic toxicity of ethanol leaf extract of Syzygium guineense on the biochemical parameters and histopathology of liver and kidney in the rats

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Long-term use of Syzygium guineense leaf extract reduced the food intake and weight gain in rats.

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The serum level of liver and kidney enzymes of rats was increased by the treatment of high dose of Syzygium guineense leaf.

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Use of Syzygium guineense leaf extract showed hypoglycemic effect in rats.

Background

Syzygium guineense Wall. leaf is being used as a traditional medicine against hypertension and diabetes mellitus. Unlike its efficacy, the safety profile of this plant upon long-term administration has not been investigated yet. Therefore, this study investigated the sub-chronic toxicity of S. guineense leaves in rats.

Methods

Wistar albino rats, 10/sex/group were randomly assigned into four groups. Group I-III respectively received 250, 500, and 1000 mg/kg of body weight of 70 % ethanol extract ofS. guineense leaves for 90 consecutive days. Group IV (control) received distilled water. Throughout the experiment, clinical observations were carried out, food intake and weight of the rats also were measured. Finally, different biochemical parameters, organ weight, and histopathology of liver and kidneys were evaluated.

Results

Administration of 70 % ethanol extract ofS. guineense leaves decreased food intake and body weight gain of the test animals. Rats treated with 1000 mg/kg of S. guineense extract showed significantly increased serum alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase levels. Serum urea levels also increased in female rats treated with 500 and 1000 mg/kg body weight of S. guineense. Moreover, the blood glucose level of rats treated with 1000 mg/kg body weight was significantly decreased compared to the control group. However, the histology of the liver and kidneys were not significantly altered by any of the doses administered.

Conclusion

Administration ofS. guineense in rats at a dose of 1000 mg/kg body weight affected the food consumption, weight gain, and serum levels of liver and kidney enzymes suggesting that S. guineense intake at high doses may be toxic. Therefore, liberal consumption of S. guineense leaves should be taken curiously and cautiously.

Glucokinase activation as antidiabetic therapy: effect of nutraceuticals and phytochemicals on glucokinase gene expression and enzymatic activity

Diabetes represents an important public health problem. Recently, new molecular targets have been identified and exploited to treat this disease. Due to its pivotal role in glucose homeostasis, glucokinase (GCK) is a promising target for the development of novel antidiabetic drugs; however, pharmacological agents that modulate GCK activity have been linked to undesirable side-effects, limiting its use. Interestingly, plants might be a valuable source of new therapeutic compounds with GCK-activating properties and presumably no adverse effects. In this review, we describe biochemical characteristics related to the physiological and pathological importance of GCK, as well as the mechanisms involved in its regulation at different molecular levels. Posteriorly, we present a compendium of findings supporting the potential use of nutraceuticals and phytochemicals in the management of diabetes through modulation of GCK expression and activity. Finally, we propose critical aspects to keep in mind when designing experiments to evaluate GCK modulation properly.

Mesenchymal Stem Cells: An Overview of Their Potential in Cell-Based Therapy for Diabetic Nephropathy

Diabetic nephropathy (DN) is a devastating complication associated with diabetes mellitus, and it is the leading cause of end-stage renal diseases (ESRD). Over the last few decades, numerous studies have reported the beneficial effects of stem cell administration, specifically mesenchymal stem or stromal cells (MSCs), on tissue repair and regeneration. MSC therapy has been considered a promising strategy for ameliorating the progression of DN largely based on results obtained from several preclinical studies and recent Phase I/II clinical trials. This paper will review the recent literature on MSC treatment in DN. In addition, the roles and potential mechanisms involved in MSC treatment of DN will be summarized, which may present much needed new drug targets for this disease. Moreover, the potential benefits and related risks associated with the therapeutic action of MSCs are elucidated and may help in achieving a better understanding of MSCs.

Functional Expression of the Human Glucose Transporters GLUT2 and GLUT3 in Yeast Offers Novel Screening Systems for GLUT-Targeting Drugs

Human GLUT2 and GLUT3, members of the GLUT/SLC2 gene family, facilitate glucose transport in specific tissues. Their malfunction or misregulation is associated with serious diseases, including diabetes, metabolic syndrome, and cancer. Despite being promising drug targets, GLUTs have only a few specific inhibitors. To identify and characterize potential GLUT2 and GLUT3 ligands, we developed a whole-cell system based on a yeast strain deficient in hexose uptake, whose growth defect on glucose can be rescued by the functional expression of human transporters. The simplicity of handling yeast cells makes this platform convenient for screening potential GLUT2 and GLUT3 inhibitors in a growth-based manner, amenable to high-throughput approaches. Moreover, our expression system is less laborious for detailed kinetic characterization of inhibitors than alternative methods such as the preparation of proteoliposomes or uptake assays in Xenopus oocytes. We show that functional expression of GLUT2 in yeast requires the deletion of the extended extracellular loop connecting transmembrane domains TM1 and TM2, which appears to negatively affect the trafficking of the transporter in the heterologous expression system. Furthermore, single amino acid substitutions at specific positions of the transporter sequence appear to positively affect the functionality of both GLUT2 and GLUT3 in yeast. We show that these variants are sensitive to known inhibitors phloretin and quercetin, demonstrating the potential of our expression systems to significantly accelerate the discovery of compounds that modulate the hexose transport activity of GLUT2 and GLUT3.

Impact of orange juice consumption on cardiovascular disease risk factors: a systematic review and meta-analysis of randomized-controlled trials

Cardiovascular disease (CVD) is the greatest cause of premature death and disability globally. Numerous therapeutic strategies have been developed to improve and prevent the adverse cardiovascular events, including nutritional approaches. This systematic review and meta-analysis summarized the evidence on orange juice consumption on CVD risk factors. Four databases were searched up to September 2020. Ten randomized controlled trials were included in the final analysis. Pooled results demonstrated a significant effect of orange juice on glucose (WMD: -2.92 mg/dl, 95% CI: -5.327, -0.530, p = 0.017), insulin (WMD: -1.229 μU/ml, 95% CI: -2.083, -0.374, p = 0.005), HOMA-IR (WMD: -0.464, 95% CI: -0.747, -0.181, p = 0.001), total cholesterol (WMD: -9.84 mg/dl, 95% CI: -15.43, -4.24, p = 0.001), LDL-C (WMD: -9.14 mg/dl, 95% CI: -15.79, -2.49, p = 0.007), and CRP (WMD: -0.467 mg/l, 95% CI: -0.815, -0.120, p = 0.008) compared to control group. However, the effect of orange juice on body composition factors and other CVD risk factors was not significant compared to control group. These lowering effects of glucose, HOMA-IR, total cholesterol, and LDL-C were robust in subgroups with orange juice consumption ≥500 ml/day. This meta-analysis suggests that orange juice may be beneficial in improving several CVD risk factors.

Phytosterols: Nutritional Health Players in the Management of Obesity and Its Related Disorders

Obesity and its related disorders, such as diabetes and cardiovascular risk, represent an emerging global health issue. Even though genetic factors seem to be the primary actors in the development and progression of these diseases, dietary choices also appear to be of crucial importance. A healthy diet combined with physical activity have been shown to ameliorate glycaemic levels and insulin sensitivity, reduce body weight and the risk of chronic diseases, and contribute to an overall improvement in quality of life. Among nutrients, phytosterols have become the focus of growing attention as novel functional foods in the management of metabolic disorders. Phytosterols are natural plant compounds belonging to the triterpene family and are structurally similar to cholesterol. They are known for their cholesterol-lowering effects, anti-inflammatory and antioxidant properties, and the benefits they offer to the immune system. The present review aims to provide an overview of these bioactive compounds and their therapeutic potential in the fields of obesity and metabolic disorders, with special attention given to oxidative stress, inflammatory status, and gut dysbiosis, all common features of the aforementioned diseases.

Proteins and peptides from vegetable food sources as therapeutic adjuvants for the type 2 diabetes mellitus

Proteins and peptides are fundamental components of the cereals, pseudocereals, and legumes, giving them numerous health-beneficial properties. Previous studies have demonstrated that these molecules exerted effects on current therapeutic targets related to type 2 diabetes mellitus, such as incretin hormones (responsible for appetite suppression), dipeptidyl peptidase IV (an enzyme involved in the inactivation and degradation of the incretin hormones), and glucose transporters (molecules that transport glucose in or out of cells). Therefore, this review presents the current biological activity of protein derivatives and peptides isolated from cereals, pseudocereals, and legumes on these therapeutic markers, highlighting their potential as a possible pharmacological treatment for type 2 diabetes mellitus.

Anti-inflammatory and antidiabetic effects of grape-derived stilbene concentrate in the experimental metabolic syndrome

AIMS

This study aimed to investigate the carbohydrate and lipid dynamics, associated inflammation markers and the effectiveness of a grape-derived stilbene concentrate (GDSC) treatment in experimental metabolic syndrome (MetS).

METHODS

The study was carried out on 40 male 12-weeks of age Wistar rats. The MetS was induced using the fructose model (feeding with 60%-solid fructose diet for 24 weeks). Rats with induced MetS were treated with polyphenolic GDSC, which was obtained by water-alcohol extraction of Vitis vinifera grapevine (Ressfood LLC, Russia).

RESULTS

The experimentally induced MetS development leads to classic MetS signs, including abdominal obesity, hyperglycemia, high lipid levels and heart damage. The expression of glucose transporter type 4 (GLUT4) and peroxisome proliferator-activated receptor-γ (PPAR-γ) had greater dynamics than biochemical measurements. The development of the associated inflammatory reactions was confirmed by the increased level of Toll-like receptor type 4 (TLR4) and C-reactive protein (CRP) compared to control levels. The use of the GDSC had positive dynamics in carbohydrate and lipid levels, inflammatory marker, also prevented associated inflammation and heart damage.