Gastro-Resistant Insulin Receptor-Binding Peptide from Momordica charantia Improved the Glucose Tolerance in Streptozotocin-Induced Diabetic Mice via Insulin Receptor Signaling Pathway

A novel heat-stable angiotensin-converting enzyme zinc-binding motif inhibitory peptide identified from corn silk

ETHNOPHARMACOLOGICAL RELEVANCE

Hypertension is the most common and chronic severe health problem globally. Corn silk (CS), the silky fibers of corn (Zea mays L.), has a long history of traditional usage as a remedy for edema and hypertension.

AIM OF THE STUDY

The aim of the study was to explore the underlying mechanism by which CS exerts its anti-hypertensive effects and investigate the presence of bioactive molecules in CS aqueous extract.

MATERIALS AND METHODS

We analyzed the effects of boiling water extract of CS on angiotensin-converting enzyme (ACE) activities, the critical enzyme involved in the regulation of blood pressure. ACE inhibitory peptides from CS extract were identified using proteomics and bioinformatics tools. The binding interfaces between these peptides and ACE were defined by hydrogen-deuterium exchange mass spectrometry (HDX-MS). Subsequently, the anti-hypertensive effects of peptides were further investigated in spontaneously hypertensive rats (SHR).

RESULTS

Our data showed that CS extract exhibited dose-dependent inhibition of ACE activity. Liquid chromatography-tandem mass spectrometry identified a heat-stable peptide bank with 1313 distinct peptide fragments within the CS boiling water extract. Among these, CS-1 (LVPGWTKPICIGR) was selected through PeptideRanker and BIOPEP-UWM analyses. In vitro ACE inhibitory assays confirmed that CS-1 exhibited dose-dependent ACE inhibition, with IC50 values of 10.32 ± 0.41 μmol/L (using HHL as the substrate) and 13.74 ± 1.87 μmol/L (using ZFHL as the substrate). Oral administration of CS-1 led to a significant dose-dependent reduction in blood pressure, with the maximal decrease (42.33 ± 13.08 mmHg) occurring 0.5 h after ingestion. HDX-MS analysis revealed that CS-1 interacted with the zinc-binding motif of ACE, and hydrogen bond interactions were predicted between CS-1 and specific residues, including His361 in the N-domain, as well as His382, Gly386, and His387 in the C-domain of ACE. These findings suggested that the interaction of CS-1 with the residues in the zinc-binding motif of ACE led to ACE activity inhibition and a subsequent decrease in blood pressure in rats.

CONCLUSIONS

A novel heat-stable ACE inhibitory peptide, which interacted with the zinc-binding motif of ACE and reduced blood pressure in SHR, was identified in the CS extract. The presence of ACE inhibitory peptides in the CS extract supports its traditional use in ethnopharmacology for hypertension.

Anti-diabetic effects of natural and modified 'Ganzhou' navel orange peel pectin on type 2 diabetic mice via gut microbiota

Pectin, a kind of dietary fiber, has attracted much attention owing to its beneficial effect on human health in recent years. In this study, the effects of both 'Ganzhou' navel orange peel pectin (GOP) and modified GOP (MGOP) on type 2 diabetes (T2DM) were investigated. The results indicated that GOP and MGOP intervention had positive effects on T2DM in C57BL/6 mice. After modification, pectin can be changed into low methoxy pectin (LMP) and the content of GalA can increase, which endow MGOP with significant effects on improving lipid metabolism (TC, TG, and LDL-C decreased by 30.46%, 50%, and 37.56%, respectively, and HDL-C increased by 56%) and OGTT, further reducing insulin resistance (insulin decreased by 74.35%). In addition, MGOP was superior to GOP in improving oxidative stress (GSH and GSH-Px increased by 52.05% and 29.08% respectively, and MDA decreased by 84.02%), inhibiting inflammation and promoting SCFA synthesis. 16S rRNA analysis showed that MGOP changed the composition of intestinal microbiota in diabetic mice, decreased the abundance of Alistipes, Helicobacter and Oscillibacter, and increased the relative abundance of Dubosiella, Akkermansiaceae, and Atopobiaceae. The phenotypes of the gut microbiome also changed accordingly, which showed that MGOP significantly inhibited the growth of Gram-negative bacteria and potential pathogenic bacteria and reversed the related complications. Taken together, our findings revealed that MGOP intake regulated lipid metabolism and oxidative stress and improved the gut health of mice, with promising effects against T2DM and related complications.

Molecular Targets and Mechanisms of Casein-Derived Tripeptides Ile-Pro-Pro and Val-Pro-Pro on Hepatic Glucose Metabolism

The objective of this study was to explore the molecular targets and mechanism of Ile-Pro-Pro (IPP) and Val-Pro-Pro (VPP) on regulating glucose metabolism in hepatic cells and their in vivo hypoglycemic activities in mice. Results showed that both IPP and VPP (600 μM) significantly enhanced the glucose consumption in HepG2 cells and primary hepatocytes (p < 0.05). They also regulated activities of glucose metabolizing enzymes and increased the protein expression of p-AKT and GLUT2 in HepG2 cells. IPP directly interacted with the insulin receptor (IR) to activate the insulin/AKT signaling pathway. The activity of VPP on glucose consumption was not attributed to IR binding, and 76 potential antidiabetic targets were predicted by similarity ensemble and shape similarity approaches. Among them, the AKT and MAPK signaling pathway, in which two hub genes AKT1 and MAPK4 existed, were evaluated to make major contributions to the activity of VPP on glucose consumption. Moreover, both IPP and VPP (300 μmol/kg) could significantly reduce the blood glucose levels in mice (p < 0.05), with blood glucose area under the curve dropping by approximately 19% ± 0.09 and 21% ± 0.11%, respectively. This study provides a new theoretical support for the development of IPP and VPP as functional foods to regulate glucose metabolic disorders.

Antioxidant and Hypoglycemic Potential of Essential Oils in Diabetes Mellitus and Its Complications

Since the earliest times, essential oils (EOs) have been utilized for medicinal and traditional purposes. However, in recent decades, an increasing interest has developed due to the need to rediscover herbal remedies and adjuvant therapies for the management of various diseases, particularly chronic ones. The present narrative review examines the potential for EOs to exert hypoglycemic and antioxidant effects in diabetes mellitus, analyzing the main publications having evaluated plant species with potentially beneficial effects through their phytocompounds in diabetes mellitus and its complications. Numerous species have shown promising characteristics that can be used in diabetes management. The hypoglycemic effects of these EOs are attributed to their capacity to stimulate glucose uptake, suppress glucose production, and increase insulin sensitivity. Moreover, EOs can alleviate the oxidative stress by manifesting their antioxidant effects via a variety of mechanisms, including the scavenging of free radicals, the regulation of antioxidant enzymes, and the decreasing of lipid peroxidation, due to their diverse chemical composition. These findings demonstrate the possible benefits of EOs as adjuvant therapeutic agents in the management of diabetes and its complications. The use of EOs in the treatment of diabetes shows good potential for the development of natural and effective strategies to enhance the health outcomes of people with this chronic condition, but additional experimental endorsements are required.

Fucus vesiculosus polysaccharide alleviates type 2 diabetes in rats via remodeling gut microbiota and regulating glycolipid metabolism-related gene expression

The antidiabetic activity and underlying mechanisms of Fucus vesiculosus polysaccharide (FVP) were studied in type 2 diabetic rats. Our results exhibited that FVP intervention reversed body weight loss, alleviated hyperglycemia and insulin resistance in diabetic rats. FVP also had the potential to ameliorate dyslipidemia, liver and kidney dysfunction, decrease oxidative stress, promote glycogen synthesis, and boost short-chain fatty acid production and total bile acid excretion. 16S rRNA gene sequencing analysis suggested that FVP interfered with the gut microbiota in a beneficial manner. Moreover, RT-qPCR results demonstrated that the antidiabetic activity of FVP in connection with the acceleration of blood glucose absorption and glycogen synthesis, the inhibition of gluconeogenesis, and the regulation of lipid metabolism in the liver. These findings suggested that FVP had antidiabetic effects on high-fat diet and STZ-induced diabetic rats and could be a potential resource for treating type 2 diabetes mellitus.

Hypoglycemic Effects of Lycium barbarum Polysaccharide in Type 2 Diabetes Mellitus Mice via Modulating Gut Microbiota

This study aims to explore the molecular mechanisms of Lycium barbarum polysaccharide (LBP) in alleviating type 2 diabetes through intestinal flora modulation. A high-fat diet (HFD) combined with streptozotocin (STZ) was applied to create a diabetic model. The results indicated that LBP effectively alleviated the symptoms of hyperglycemia, hyperlipidemia, and insulin resistance in diabetic mice. A high dosage of LBP exerted better hypoglycemic effects than low and medium dosages. In diabetic mice, LBP significantly boosted the activities of CAT, SOD, and GSH-Px and reduced inflammation. The analysis of 16S rDNA disclosed that LBP notably improved the composition of intestinal flora, increasing the relative abundance of Bacteroides, Ruminococcaceae_UCG-014, Intestinimonas, Mucispirillum, Ruminococcaceae_UCG-009 and decreasing the relative abundance of Allobaculum, Dubosiella, Romboutsia. LBP significantly improved the production of short-chain fatty acids (SCFAs) in diabetic mice, which corresponded to the increase in the beneficial genus. According to Spearman’s correlation analysis, Cetobacterium, Streptococcus, Ralstonia. Cetobacterium, Ruminiclostridium, and Bifidobacterium correlated positively with insulin, whereas Cetobacterium, Millionella, Clostridium_sensu_stricto_1, Streptococcus, and Ruminococcaceae_UCG_009 correlated negatively with HOMA-IR, HDL-C, ALT, AST, TC, and lipopolysaccharide (LPS). These findings suggested that the mentioned genus may be beneficial to diabetic mice’s hypoglycemia and hypolipidemia. The up-regulation of peptide YY (PYY), glucagon-like peptide-1 (GLP-1), and insulin were remarkably reversed by LBP in diabetic mice. The real-time PCR (RT-PCR) analysis illustrated that LBP distinctly regulated the glucose metabolism of diabetic mice by activating the IRS/PI3K/Akt signal pathway. These results indicated that LBP effectively alleviated the hyperglycemia and hyperlipidemia of diabetic mice by modulating intestinal flora.

A gastro-resistant peptide from Momordica charantia improves diabetic nephropathy in db/db mice via its novel reno-protective and anti-inflammatory activities

Diabetic nephropathy (DN), a principal diabetic microvascular complication, is a chronic inflammatory immune disorder. A gastro-resistant peptide mcIRBP-9 from Momordica charantia has shown modulation of blood glucose homeostasis in diabetic mice. Here we conducted a long-term experiment to evaluate the therapeutic effects and mechanisms of mcIRBP-9 on DN. Type 2 diabetic mice (db/db mice) were orally given mcIRBP-9 once daily for 12 consecutive weeks. The amelioration of DN was evaluated by renal function indexes, vascular leakage, and pathological lesions. Possible effective mechanisms of mcIRBP-9 on DN were analyzed by gene expression profiles. A pharmacokinetic study in rats was carried out to evaluate the oral bioavailability of mcIRBP-9. Our data showed that mcIRBP-9 was able to enter systemic circulation in rats after oral administration. In comparison with mock, long-term administration of mcIRBP-9 significantly decreased blood glucose (572.25 ± 1.55 mg dL^-1vs. 213.50 ± 163.39 mg dL^-1) and HbA1c levels (13.58 ± 0.30% vs. 8.23 ± 2.98%) and improved the survival rate (85.7% vs. 100%) in diabetic mice. mcIRBP-9 ameliorated DN by reducing renal vascular leakage and histopathological changes. mcIRBP-9 altered the pathways involved in inflammatory and immune responses, and the nuclear factor-κB played a central role in the regulation of mcIRBP-9-affected pathways. Moreover, mcIRBP-9 improved the inflammatory characteristic of DN in diabetic and non-diabetic mice. In conclusion, mcIRBP-9 displayed a novel anti-inflammatory activity and exhibited a reno-protective ability in addition to controlling the blood glucose and HbA1c levels. These findings suggested the role of mcIRBP-9 from M. charantia as a nutraceutical agent for diabetes and subsequent DN.

A randomized, double-blind, placebo-controlled trial to evaluate the hypoglycemic efficacy of the mcIRBP-19-containing

Background

The fruits of Momordica charantia L., also named as bitter gourd or bitter melon in popular, is a common tropical vegetable that is traditionally used to reduce blood glucose. A peptide derived from bitter gourd, Momordica charantia insulin receptor binding peptid-19 (mcIRBP-19), had been demonstrated to possess an insulin-like effect in vitro and in the animal studies. However, the benefit of the mcIRBP-19-containing bitter gourd extracts (mcIRBP-19-BGE) for lowering blood glucose levels in humans is unknown.

Objective

This aim of this study was to evaluate the hypoglycemic efficacy of mcIRBP-19-BGE in subjects with type 2 diabetes who had taken antidiabetic medications but failed to achieve the treatment goal. Whether glucose lowering efficacy of mcIRBP-19-BGE could be demonstrated when the antidiabetic medications were ineffective was also studied.

Design

Subjects were randomly assigned to two groups: mcIRBP-19-BGE treatment group (N = 20) and placebo group (N = 20), and were orally administered 600 mg/day investigational product or placebo for 3 months. Subjects whose hemoglobin A1c (HbA1c) continued declining before the trial initiation with the antidiabetic drugs were excluded from the subset analysis to further investigate the efficacy for those who failed to respond to the antidiabetic medications.

Results

The oral administration of mcIRBP-19-BGE decreased with a borderline significance at fasting blood glucose (FBG; P = 0.057) and HbA1c (P = 0.060). The subgroup analysis (N = 29) showed that mcIRBP-19-BGE had a significant effect on reducing FBG (from 172.5 ± 32.6 mg/dL to 159.4 ± 18.3 mg/dL, P = 0.041) and HbA1c (from 8.0 ± 0.7% to 7.5 ± 0.8%, P = 0.010).

Conclusion

All of these results demonstrate that mcIRBP-19-BGE possesses a hypoglycemic effect, and can have a significant reduction in FBG and HbA1c when the antidiabetic drugs are ineffective.

The novel anti-inflammatory activity of mcIRBP from Momordica charantia is associated with the improvement of diabetic nephropathy

Diabetic nephropathy is an inflammatory immune disorder accompanying diabetes.

Valorisation of food agro-industrial by-products: From the past to the present and perspectives

Food agro-industrial by-products mainly include peels, seeds, stems, bagasse, kernels, and husk, derived during food processing. Due to their overproduction and the lack of sustainable management, such by-products have been conventionally rejected and wasted in landfills, being the principal strategy for their treatment, but nowadays, this strategy has been associated with several environmental, social and economic issues. Hence, we focused on the use of different consolidated biotechnological processes and methodologies as suitable strategies for food by-products management and valorisation, highlighting them as potential bioresources because they still gather high compositional and nutritional value, owing to their richness in functional and bioactive molecules with human health benefits. Food by-products could be utilised for the development of new food ingredients or products for human consumption, promoting their integral valorisation and reincorporation to the food supply chain within the circular bioeconomy concept, creating revenue streams, business and job opportunities. In this review, the main goal was to provide a general overview of the food agro-industrial by-products utilised throughout the years, improving global sustainability and human nutrition, emphasising the importance of biowaste valorisation as well as the methodologies employed for the recovery of value-added molecules.

The Effect of Momordica charantia in the Treatment of Diabetes Mellitus: A Review

In recent years, many studies of Momordica charantia (MC) in the treatment of diabetes mellitus (DM) and its complications have been reported. This article reviewed the effect and mechanism of MC against diabetes, including the results from in vitro and in vivo experiments and clinical trials. The common side effects of MC were also summarized. We hope that it might open up new ideas for further mechanism exploration and clinical application as well as provide a scientific theoretical basis for the development of drugs or foods derived from MC.

Mitigation mechanisms of Hizikia fusifarme polysaccharide consumption on type 2 diabetes in rats

The objective of current work was to explore the potential anti-diabetic mechanisms of Hizikia fusifarme polysaccharide (HFP) in type 2 diabetic rats. The carbohydrate loading experiment illustrated that HFP supplement could reduce blood sugar fluctuations caused by eating through inhibiting the hydrolysis of starch in mice. The analysis of typically diabetic symptoms and serum profiles showed that oral administration of HFP could mitigate hyperglycemia, insulin resistance, dyslipidemia, chronic inflammation and oxidative stress in rats. The 16s rRNA gene sequencing analysis indicated that HFP treatment could restore beneficial composition of gut flora in diabetic rats, and the correlation analysis revealed that the improvement of diabetes is closely related to the modification of gut flora by HFP intervention. Furthermore, the RT-qPCR and western blotting analysis clarified that HFP administration could increase glycogen storage in liver and skeletal muscle of diabetic rats through activating IRS/PI3K/AKT/GLUT signaling pathway and restrain gluconeogenesis via affecting the relative expression of Egr-1 and PEPCK genes.

Antidiabetic effects and underlying mechanisms of anti-digestive dietary polysaccharides from Sargassum fusiforme in rats

Sargassum fusiforme polysaccharides (SFP), an anti-digestive biologically active ingredient obtained from Sargassum fusiforme by ultrasound-assisted enzymatic extraction, have been proven to exhibit extremely strong alpha-glucosidase inhibitory activity. In the current research, the potential anti-diabetic effects and molecular mechanisms of SFP were investigated by classic biochemical analysis, high-throughput sequencing and molecular biology techniques in type 2 diabetic rats. The analysis of typical diabetic symptoms and serum profiles showed that oral administration of SFP could mitigate hyperglycemia, hyperinsulinemia, dyslipidemia and oxidative stress in diabetic rats. SFP also promoted glycogen synthesis in the liver and skeletal muscles. H&E staining observation confirmed that SFP intervention could partially repair liver and muscle injuries caused by diabetes. Moreover, 16S rRNA gene sequencing analysis indicated that SFP treatment could distinctly restore the beneficial composition of gut flora in diabetic rats. Furthermore, RT-qPCR analysis revealed that anti-diabetic effects of SFP may be closely related to accelerating the absorption and utilization of blood glucose in the liver and muscle and inhibiting hepatic glucose production. In short, this study demonstrated that SFP could be developed as functional foods or pharmaceutical supplements for the prevention or mitigation of diabetes and its complications.

A chemical valorisation of melon peels towards functional food ingredients: Bioactives profile and antioxidant properties

The goal of this work was to characterize the profile of bioactive compounds and the antioxidant activity of inodorus melon peels. Melon peels were divided into three fractions: a solid fraction with a higher content of carbohydrates (84.81%); a liquid fraction with a higher ash content (11.5%); and a pellet fraction with a higher protein content (34.90%). The structural carbohydrates study revealed a composition of cellulose (27.68%), hemicellulose (8.2%) and lignin (26.46%) in the solid fraction. The liquid fraction had the highest antioxidant activity based on results from DPPH, ABTS and ORAC assays. Flavones, hydroxybenzoic and hydroxycinnamic acids were the main phenolic classes found in all fractions. In addition, β-carotene, lutein, β-cryptoxanthin and violaxanthin had also been quantified. Melon fractions were rich in nutrients and bioactive substances and could be useful in the development of novel functional products, considering the growing market demand for safe and healthy food products.

Effect of Caesalpinia bonduc Polyphenol Extract on Alloxan-Induced Diabetic Rats in Attenuating Hyperglycemia by Upregulating Insulin Secretion and Inhibiting JNK Signaling Pathway

Caesalpinia bonduc has been used in herbal medicines for the treatment of a wide range of diseases from decades. The present study has explored the remedial potential and underlying mechanism of polyphenol extract of Caesalpinia bonduc in alloxanized diabetic rats. HPLC/MS analysis confirmed the presence of phenolics in considerable concentrations in Caesalpinia bonduc extract. Administration of different doses (250 and 500 mg/kg) of CPP extract to hyperglycemic rats for 8 weeks restored blood and serum glucose, insulin, glycosylated hemoglobin, leptin, amylin, and carbohydrate metabolizing enzymes level towards normal compared to alloxanized diabetic group. The effect of CPP extract on various genes such as Pdx-1, Ins-1, ngn-3, GLUT-4, and IRS-1 in insulin signaling pathway and Traf-4, Traf-6, and Mapk-8 in MAPK downstream JNK cascade was examined through qRT-PCR to access the core molecular mechanism involved in CPP-induced recovery of diabetes. Results have revealed that CPP extract reduced oxidative stress in pancreatic β cells by restoring free radical scavenging potential, reducing the mRNA expression of Mapk-8, Traf-4, and Traf-6, and increasing the Pdx-1, Ins-1, ngn-3, GLUT-4, and IRS-1 expression ensuing regeneration of β cells and subsequent insulin release from pancreas. The results obtained in this study recommend that CPP extract may be a promising therapeutic restorative agent in the treatment of diabetes mellitus.

Polysaccharide from Rosa roxburghii Tratt Fruit Attenuates Hyperglycemia and Hyperlipidemia and Regulates Colon Microbiota in Diabetic db/db Mice

This study was aimed at investigating the hypoglycemic and hypolipidemic effects of a polysaccharide (RTFP) isolated from Rosa roxburghii Tratt fruit on type-2 diabetic db/db mice. The results indicated that the oral administration of RTFP could significantly decrease the body weight, fat, and liver hypertrophy and the levels of fasting blood glucose, serum insulin, and serum lipids of the db/db mice. Histopathological observation showed that RTFP could effectively protect the pancreas, liver, and epididymal fat against damage and dysfunction. Real-time quantitative polymerase chain reaction analysis confirmed that the gene expression levels of peroxisome proliferator-activated receptors-γ (PPAR-γ), sterol regulatory element-binding protein-1 (SREBP-1c), acetyl-CoA carboxylase-1 (ACC-1), fatty acid synthase (FAS), and glucose-6-phosphatase (G6 Pase) were significantly down-regulated in the liver of db/db mice after treatment with RTFP. Moreover, RTFP treatment reversed gut dysbiosis by lowering the Firmicutes-to-Bacteroidetes ratio and enhancing the relative abundances of beneficial bacteria including Bacteroidaceae, Bacteroidaceae S24-7 group, and Lactobacillaceae. These findings suggest that RTFP can be used as a promising functional supplement for the prevention and treatment of type-2 diabetes mellitus.

Postprandial Glucose Levels Are Better Associated with the Risk Factors for Diabetes Compared to Fasting Glucose and Glycosylated Hemoglobin (HbA1c) Levels in Elderly Prediabetics: Beneficial Effects of Polyherbal Supplements-A Randomized, Double-Blind, Placebo Controlled Trial

Backgrounds

Prediabetes is a condition in which a person's blood glucose levels are higher than normal physiological levels but lower compared to patients with diabetes. Up to 70% of individuals with prediabetes will eventually develop diabetes. To date, there have been no pharmaceutical drugs to treat diabetes. It is believed that early diagnosis and nonpharmacological intervention for prediabetes are critical for effective prevention of diabetes. Most individuals with prediabetes remain undiagnosed even after being evaluated using the standard tests for fasting glucose (FG) and HbA1c. We investigated if postprandial glucose levels (2h-PG) were associated with pre/diabetes and if polyherbal supplements could be beneficial for individuals with prediabetes.

Materials and Methods

100 elderly individuals with impaired 2h-PG or fasting glucose levels were recruited to receive either a 12-week supplement of GlucoVita (an antioxidative polyherbal formulation) (n=50) or placebo (n=50).

Results

No baseline differences were observed for FG, HbA1c, or 2h-PG. Individuals who received a twelve-week administration of GlucoVita supplements had significantly reduced 2h-PG (8.15±1.67 versus 7.35±2.06 mmol/l, P<0.05) levels compared to individuals in the placebo group. In addition, HbA1c levels were lower in individuals who received GlucoVita (5.81±0.49 %) compared to the individuals in the placebo group (6.00±0.51%) (P=0.08) after 12-weeks. Stratified analysis, based on impaired fasting glucose (IFG), 2h-PG, metabolic symptom, and age, demonstrated that, after the 12-week intervention, HbA1c levels were significantly lower in the GlucoVita administered group compared to the placebo group (IFG subgroup; 5.85±0.46%, n= 27 versus 6.14±0.50, n=33, P<0.05) and the metabolic symptom-free subgroup (5.73±0.45%, n=23 versus 6.04±0.52%, n=24, P<0.05). GlucoVita also reduced FG in individuals with normal 2h-PG (6.37±0.27 versus 6.08±0.38 mmol/l, P<0.05). Baseline 2h-PG levels, but not HbA1c or FG levels, were significantly correlated with body weight, waist circumference, and BMI (r=0.25, P<0.05; r=0.31, P<0.01; r=0.22, P<0.05, respectively).

Conclusion

2h-PG levels were better associated with body weight, waist circumference, and BMI risk factors compared to FG and HbA1c levels in elderly individuals with prediabetes. Polyherbal formulation GlucoVita supplements improved 2h-PG and HbA1c levels only in elderly individuals who were overweight but were symptom-free and under 65 years of age. Due to the small cohort size of this pilot study, future studies are required to validate our findings.

Vanillin-Ameliorated Development of Azoxymethane/Dextran Sodium Sulfate-Induced Murine Colorectal Cancer: The Involvement of Proteasome/Nuclear Factor-κB/Mitogen-Activated Protein Kinase Pathways

Vanillin is a natural dietary flavoring widely used in the food industry. Colorectal cancer (CRC) is one of the common malignancies in the world. Chronic intestinal inflammation is a risk factor for the development of CRC. We have previously found that vanillin improves and prevents colitis in mice. Here we evaluated the inhibitory activities of vanillin on a mouse model of colitis-induced CRC. Mice were challenged intraperitoneally with azoxymethane (AOM) and orally with dextran sodium sulfate (DSS). Various dosages of vanillin were orally administered for 13 consecutive weeks. Vanillin alleviated the development of tumors in AOM/DSS-induced mice. The total number of tumors in 100 mg/kg vanillin group was significantly reduced by 57.14 ± 7.67%, compared with sham group. Gene expression analysis showed that vanillin downregulated the expression levels of proteasome genes in colon tissues. Moreover, vanillin at 10 mM significantly suppressed proteasome activities in HCT-116 cells by 41.27 ± 0.41%. Furthermore, vanillin diminished the phosphorylation of mitogen-activated protein kinases (MAPKs) and reduced the number of p65-positive cells, proliferating cells, and granulocytes in colon tissues with statistical significance. In conclusion, our data suggested that vanillin was a bioactive compound that ameliorated the development of AOM/DSS-induced colon cancer in mice. Moreover, the amelioration of vanillin might be associated with the downregulation of proteasome, nuclear factor-κB, and MAPK pathways.

The Effect of Sanggua Drink Extract on Insulin Resistance through the PI3K/AKT Signaling Pathway

Treating type 2 diabetes mellitus (T2DM) using thiazolidinediones and biguanides can present several challenges for patients. Sanggua Drink (SGD) is a commonly used agent in traditional Chinese medicine, and it consists of Folium Mori, Fructus Momordicae Charantiae, Radix Puerariae Lobatae, and Rhizoma Dioscorea. The hypoglycemic effects and mechanisms of SGD extracts on insulin resistance in diabetic rats were investigated. SGD (1.24 g/kg orally) was verified in T2DM rats induced by a high-fat diet and streptozotocin. The results showed that SGD treatment was observed to reduce fasting blood glucose, water and food intake, total cholesterol triglycerides, and LDL, OGTT, FINS, HOMA-IR, GHb, and MDA and increase hepatic glycogen, HDL, SOD, CAT, and GSH-Px in diabetic rats. Simultaneously, SGD treatment by T2DM showed significantly ameliorated pathological changes and reduced inflammation in the pancreas. Treatment was also observed to increase gene and protein expressions of InsR, IRS-2, PI3K, AKT, and Glut4 in the livers of diabetic treated rats. These results suggest that SGD extracts have hypoglycemic properties and may alleviate insulin resistance in T2DM rats through the PI3K/AKT pathway. Therefore, SGD appears to be a promising insulin sensitizer.