Mulberry (Morus alba L.) Fruit Extract Containing Anthocyanins Improves Glycemic Control and Insulin Sensitivity via Activation of AMP-Activated Protein Kinase in Diabetic C57BL/Ksj-db/db Mice

Improvement of Glucose Metabolism by Pennogenin 3-O-β-Chacotrioside via Activation of IRS/PI3K/Akt Signaling and Mitochondrial Respiration in Insulin-Resistant Hepatocytes

SCOPE

Insulin resistance (IR), which causes chronic hyperglycemia, has been one of the most prevalent components of metabolic syndrome over the centuries. Pennogenin 3-O-β-chacotrioside (P3C), the main steroid glycoside derived from Paris polyphylla, has been found to exert various biological activities. However, the exact role of P3C on glucose metabolism in the IR state remains unexplored.

METHODS AND RESULTS

To induce IR, AML12 cells were exposed to glucose (27 mM) and insulin (10 µg/mL) and then incubated with P3C (0.25 or 0.5 µM) for 24 h. The effects of P3C on glucose metabolism in insulin-resistant AML12 cells were evaluated through glucose consumption assays, real-time quantitative polymerase chain reaction (qPCR), Western blotting, and metabolic analysis for extracellular acidification rate (ECAR) and oxygen consumption rate (OCR). Our data showed that P3C significantly improved insulin sensitivity in AML12 hepatocytes with high glucose-induced IR. P3C stimulated insulin sensitivity and glucose uptake by activating the IRS/PI3K/Akt signaling pathway, which enhances glycogen synthesis and suppresses gluconeogenesis in insulin-resistant AML12 cells. In addition, P3C treatment increased the protein expression of p-AMPK and PGC1α, as well as the expression of oxidative phosphorylation complex proteins, potentially enhancing mitochondrial oxidative respiration.

CONCLUSIONS

Our findings imply that P3C could be a therapeutic option for improving metabolic abnormalities associated with IR.

Study protocol, menu design, and rationale for a study testing the effects of a whole fruit-rich diet on glycemic control, liver fat, pancreatic fat, and cardiovascular health in adults with type 2 diabetes

Dietary interventions such as very-low-calorie diets and low-carbohydrate diets can improve glycemic control and even induce type 2 diabetes (T2D) remission. However, less is known about the effects of carbohydrate-rich whole foods, such as whole fruit, in people with T2D. Therefore, the aim of this pilot study is to investigate the effects of a whole fruit-rich diet on glycemic control, ectopic fat, and cardiovascular risk factors in adults with T2D. In this pilot study, sixteen adults aged 20 to 70 years with insulin-independent T2D for ≤6 years will complete a 12-week controlled-feeding intervention while maintaining their weight. During the ramp-up phase (weeks 1-4), participants progressively consume more whole fruit. During weeks 5 to 12, participants eat a fruit-rich Mediterranean diet providing 50% of calories as whole fruit (∼16.4 servings/day). All outcomes are measured at weeks 0, 4, and 12. The primary outcome is glycemic control, assessed hierarchically by whether participants achieve nondiabetic glucose concentrations without antihyperglycemic medications; the total dose of antihyperglycemic medications; mean glucose during a three-hour oral glucose tolerance test; and mean 24-hour glucose from continuous glucose monitoring. Secondary outcomes include intrahepatic lipid, pancreatic fat, blood pressure, heart rate, and serum lipids. We hypothesize that a fruit-rich diet will improve glycemic control, reduce the need for antihyperglycemic medications, decrease ectopic fat, and improve cardiovascular risk factors. This novel study will help determine the effects of a whole fruit-rich diet on glycemic control and liver fat and whether diabetes remission may be possible without losing weight. This study was registered at ClinicalTrials.gov (NCT03758742).

Anthocyanin-Binding Affinity and Non-Covalent Interactions with IIS-Pathway-Related Protein Through Molecular Docking

Anthocyanins compounds, including cyanidin, malvidin, pelargonidin, peonidin, and petunidin, have demonstrated remarkable anti-aging and insulin-sensitizing properties through their interactions with proteins associated with the insulin/insulin-like growth factor signaling (IIS) pathway in Reticulitermes chinensis, employing advanced molecular docking techniques to elucidate strong binding affinities between specific anthocyanins and key proteins such as Pdk1, EIF4E, and Tsc2 in R. chinensis, suggesting a potential mechanism for their anti-aging effects. These findings not only provide critical insights into the therapeutic potential of anthocyanins for mitigating insulin resistance and promoting longevity, but also highlight the efficacy of in silico molecular docking as a predictive tool for small-molecule-protein interactions. Our research opens new avenues for the development of innovative therapeutic strategies targeting age-related diseases. However, further investigations, including a comprehensive chromosomal analysis and in vivo studies, are essential in order to fully elucidate the molecular mechanism underlying these interactions and their physiological implications. The detailed characterization of anthocyanin-binding affinities and their interactions with key regulatory genes presents exciting opportunities for advancement in molecular medicine, pharmacology, and the development of novel nutraceuticals.

Anthocyanin-rich black wheat as a functional food for managing type 2 diabetes mellitus: a study on high fat diet-streptozotocin-induced diabetic rats

Background: Type 2 Diabetes Mellitus (T2DM) is associated with insulin resistance, hyperglycemia, and hyperlipidemia. Anthocyanins, which are natural antioxidants, have been reported to manage T2DM-related complications. However, the potential of anthocyanin-rich black wheat as a functional food for managing diabetes remains unexplored. Aim: This study aimed to investigate the effects of anthocyanin-rich black wheat on glucose metabolism, insulin sensitivity, lipid profile, oxidative stress, inflammation, and organ protection in high fat diet-streptozotocin (HFD-STZ) induced T2DM rats. Methods: T2DM was induced in rats using HFD-STZ. The rats were fed with either white wheat or anthocyanin-rich black wheat chapatti. Glucose metabolism, insulin sensitivity, lipid profile, antioxidant enzymes, inflammatory markers, and glucose transporters were assessed. Histopathological analysis of the liver, kidneys, and spleen was performed. Results: Compared to white wheat chapatti, black wheat chapatti exhibited higher α-amylase and α-glucosidase inhibitory activities. Black wheat chapatti consumption significantly reduced blood glucose and HbA1c levels, and improved insulin sensitivity, oral glucose tolerance, and insulin tolerance. Antioxidant enzyme (superoxide dismutase and catalase) activities were enhanced. Atherogenic dyslipidemia was attenuated, with improved high-density lipoprotein cholesterol levels. Inflammatory markers (TNF-α, IL-1β, leptin, resistin and cortisol) were reduced, while adiponectin (Acrp-30) levels increased. Black wheat chapatti activated adiponectin-AMPK and PI3K-AKT pathways, upregulating glucose transporters (GLUT-2 and GLUT-4). Histopathology revealed protective effects on the liver, kidneys, and spleen. Conclusions: Anthocyanin-rich black wheat chapatti ameliorates insulin resistance and associated complications in HFD-STZ-induced T2DM rats. It modulates key signaling pathways and glucose transporters, demonstrating its potential as a functional food for managing T2DM and its complications.

Subchronic oral toxicity study of the synbiotic mulberry in male and female Wistar rats

Mulberry (Morus alba L) fruit is traditionally used in Chinese medicine and has several beneficial effects, such as hypoglycemic, hypolipidemic, and anti-oxidative effects. We previously developed the synbiotic mulberry (SM) containing probiotic Lactobacilli, prebiotic inulin, and mulberry powder. In food supplement development, toxicity is the most important criterion in food and drug regulations before commercialization. Thus, this study aimed to investigate the subchronic toxicity of SM in male and female Wistar rats to evaluate its biosafety. The subchronic toxicity study was conducted by daily oral administration of SM at doses of 250, 500, and 1000 mg/kgBW for 90 days. Male and female rats were evaluated for body weight, organ coefficients, biochemical and hematological parameters, and vital organ histology. The results showed no mortality or toxic changes in the subchronic toxicity study. These results suggested that no observed adverse effect level (NOAEL) of SM in male and female rats has been considered at 1000 mg/kgBW for subchronic toxicity study.

Effect of dietary anthocyanins on biomarkers of type 2 diabetes and related obesity: A systematic review and meta-analysis

Anthocyanins have been reported for the protective effects against type 2 diabetes and related obesity. This meta-analysis examined the benefits of anthocyanins on type 2 diabetes and obesity biomarkers in animals and humans. The study included 21 clinical trials and 27 pre-clinical studies. A systematic search was conducted using the following inclusion criteria: in vivo rodent studies; human randomized clinical trials, both aimed at assessing the fasting blood glucose (FBG), HbA1c, total cholesterol, triglycerides, high-density lipoprotein and low-density lipoprotein; and study duration of at least two weeks. Out of the 201 examined publications, 48 were shortlisted after implementation of the selection criteria. Results of clinical trials demonstrated that consumption of anthocyanin-rich food significantly reduced the FBG (p < 0.0001), HbA1c (p = 0.02), TC (p = 0.010), TG (p = 0.003), LDL (p = 0.05) and increases the HDL (p = 0.03) levels. Similarly, pre-clinical studies demonstrated the amelioration of the HbA1c (p = 0.02), FBG, TC, TG, and LDL (p < 0.00001), with non-significant changes in the HDL (p = 0.11). Sub-group analysis indicated dose-dependent effect. This compilation confirms that consuming anthocyanin-rich foods positively correlates with the reduction in the blood glucose and lipid levels in diabetic and obese subjects.

Diet-Induced Rodent Obesity Is Prevented and the Fecal Microbiome Is Improved with Elderberry (Sambucus nigra ssp. canadensis) Juice Powder

Anthocyanin-rich edible berries protect against diet-induced obesity in animal models. Prevention is mediated through the bidirectional relationship with the fecal microbiome, and gut-derived phenolic metabolite absorption increases with physical activity, which may influence bioactivity. The objective of this study was to test elderberry juice powder on the development of diet-induced obesity and its influence on the fecal microbiome alone or in combination with physical activity. Male C57BL/6J mice were assigned to one of four treatments, including (1) high-fat diet without wheel access; (2) high-fat diet with unlimited wheel access; (3) high-fat diet supplemented with 10% elderberry juice powder without wheel access; and (4) high-fat diet supplemented with 10% elderberry juice powder with unlimited wheel access. Body weight gain, fat pads, and whole-body fat content in mice fed elderberry juice were significantly less than in mice fed the control diet independent of wheel access. At the end of the study, active mice fed elderberry juice ate significantly more than active mice fed a control diet. There was no difference in the physical activity between active groups. Elderberry juice increasedBifidobacterium, promotedAkkermansia and Anaeroplasma, and prevented the growth of Desulfovibrio. Elderberry juice is a potent inhibitor of diet-induced obesity with action mediated by the gut microbiota.

Anthocyanins' effects on diabetes mellitus and islet transplantation

The incidence of diabetes mellitus is dramatically increasing every year, causing a huge global burden. Moreover, existing anti-diabetic drugs inevitably bring adverse reactions, and the application of islet transplantation is often limited by the damage caused by oxidative stress after transplantation. Thus, new approaches are needed to combat the growing burden of diabetes mellitus. Anthocyanins are of great nutritional interest and have been documented that have beneficial effects on chronic diseases, including diabetes mellitus. Here, we describe the health effects of anthocyanins on diabetes mellitus and islet transplantation. Epidemiological studies demonstrated that moderate intake of anthocyanins leading to a reduction in risk of diabetes mellitus. Numerous experiments both animal and clinical studies also showed positive effects of anthocyanins on prevention and treatment of diabetes and diabetic complications. These effects of anthocyanins may be related to mechanisms of improving glucose and lipid metabolism and insulin resistance, antioxidant, and anti-inflammatory activities. In addition, damage and function of pancreatic islets after transplantation are also improved by anthocyanins. These findings suggest that daily intake of anthocyanins may not only improve nutritional metabolism in healthy individuals to prevent from diabetes, but also as a supplementary treatment of diabetes mellitus and islet transplantation. Thus, more evidence is needed to better understand the potential health benefits of anthocyanins.

Pathophysiology of diabetic hepatopathy and molecular mechanisms underlying the hepatoprotective effects of phytochemicals

Patients with diabetes are at risk for liver disorders including glycogen hepatopathy, non-alcoholic fatty liver disease, cirrhosis, and hepatic fibrosis. The pathophysiological mechanisms behind diabetic hepatopathy are complex, some of them include fatty acid accumulation, increased reactive oxygen species, increased advanced glycation end-products, hyperactivity of polyol pathways, increased apoptosis and necrosis, and promotion of fibrosis. A growing number of studies have shown that herbal extracts and their active phytochemicals have antihyperglycemic properties and beneficial effects on diabetic complications. The current review, for the first time, focused on herbal agents that showed beneficial effects on diabetic hepatopathy. For example, animal studies have shown that Moringa oleifera and Morus alba improve liver function in both type-1 and type-2 diabetes. Also, evidence from clinical trials suggests that Boswellia serrata, Juglans regia, Melissa officinalis, Portulaca oleracea, Silybum marianum, Talapotaka Churna, and Urtica dioica reduce serum liver enzymes in diabetic patients. The main active ingredient of these plants to protect the liver seems to be phenolic compounds such as niazirin, chlorogenic acid, resveratrol, etc. Mechanisms responsible for the hepatoprotective activity of herbal agents include improving glucose metabolism, restoring adipokines levels, antioxidant defense, and anti-inflammatory activity. Several signaling pathways are involved in hepatoprotective effects of herbal agents in diabetes, such as phosphoinositide 3-kinase, adenosine monophosphate-activated protein kinase, mitogen-activated protein kinase, and c-Jun NH2-terminal kinase.

Morus alba: a comprehensive phytochemical and pharmacological review

Morus alba is a fast-growing shrub or medium-sized tree with a straight, cylindrical trunk. Medicinally, whole plants, leaves, fruits, branches, and roots have been employed. Google Scholar, PubMed, Scopus, and Web of Science were used to search for relevant material on the phytochemical components and pharmacologic and mechanism of action of the Morus alba. This was reviewed to assess important updates about Morus alba. The fruits of Morus alba have traditionally been used as an analgesic, anthelmintic, antibacterial, anti-rheumatic, diuretic, hypotensive, hypoglycemia, purgative, restorative, sedative tonic, and blood stimulant. Various plant parts were used as a cooling, sedating, diuretic, tonic, and astringent agent to treat nerve disorders. The plant contained tannins, steroids, phytosterols, sitosterol, glycosides, alkaloids, carbohydrates, proteins, and amino acids, as well as saponins, triterpenes, phenolics, flavonoids, benzofuran derivatives, anthocyanins, anthraquinones, glycosides, vitamins, and minerals. Previous pharmacological research identified antimicrobial, anti-inflammatory, immunological, analgesic, antipyretic, antioxidant, anti-cancer, antidiabetic, gastrointestinal, respiratory, cardiovascular, hypolipidemic, anti-obesity, dermatological, neurological, muscular, and protecting effects. This study looked at Morus alba's traditional uses, chemical components, and pharmacological effects.

Food Polyphenols and Type II Diabetes Mellitus: Pharmacology and Mechanisms

Type II diabetes mellitus and its related complications are growing public health problems. Many natural products present in our diet, including polyphenols, can be used in treating and managing type II diabetes mellitus and different diseases, owing to their numerous biological properties. Anthocyanins, flavonols, stilbenes, curcuminoids, hesperidin, hesperetin, naringenin, and phenolic acids are common polyphenols found in blueberries, chokeberries, sea-buckthorn, mulberries, turmeric, citrus fruits, and cereals. These compounds exhibit antidiabetic effects through different pathways. Accordingly, this review presents an overview of the most recent developments in using food polyphenols for managing and treating type II diabetes mellitus, along with various mechanisms. In addition, the present work summarizes the literature about the anti-diabetic effect of food polyphenols and evaluates their potential as complementary or alternative medicines to treat type II diabetes mellitus. Results obtained from this survey show that anthocyanins, flavonols, stilbenes, curcuminoids, and phenolic acids can manage diabetes mellitus by protecting pancreatic β-cells against glucose toxicity, promoting β-cell proliferation, reducing β-cell apoptosis, and inhibiting α-glucosidases or α-amylase. In addition, these phenolic compounds exhibit antioxidant anti-inflammatory activities, modulate carbohydrate and lipid metabolism, optimize oxidative stress, reduce insulin resistance, and stimulate the pancreas to secrete insulin. They also activate insulin signaling and inhibit digestive enzymes, regulate intestinal microbiota, improve adipose tissue metabolism, inhibit glucose absorption, and inhibit the formation of advanced glycation end products. However, insufficient data are available on the effective mechanisms necessary to manage diabetes.

Mulberry extract ameliorates T2DM-related symptoms via AMPK pathway in STZ-HFD-induced C57BL/6J mice

ETHNOPHARMACOLOGICAL RELEVANCE

Mulberry (Morus alba L.) is not only a tasty food but also a beneficial medicinal substance that has been historically used to treat diabetes, as recorded in Tang Ben Cao. Recent research on animal models has shown that the ethyl acetate extract of Morus alba L. fruits (EMF) has hypoglycemic and hypolipidemic properties. However, there is a lack of documentation on the specific mechanisms through which EMF exerts its hypoglycemic effects.

OBJECTIVE OF THE STUDY

This study aimed to investigate the impact of EMF on L6 cells and C57/BL6J mice and to elucidate the potential mechanisms underlying its effects. The findings of this study can contribute to the existing evidence for the application of EMF as a therapeutic drug or dietary supplement in the management of type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

The UPLC-Q-TOF-MS technique was utilized to gather MS data. Masslynx 4.1 software in conjunction with the SciFinder database and other relevant references were used to analyze and identify the chemical composition of EMF. A series of in vitro investigations including MTT assay, glucose uptake assay and Western blot analysis were performed using an L6 cell model stably expressing IRAP-mOrange after EMF treatment. In vivo investigations were performed on a STZ-HFD co-induced T2DM mouse model, which included assessments of body composition, biochemical tests, histopathological analysis, and Western blot analysis.

RESULTS

MTT results revealed that EMF had no toxic effects on the cells at various concentrations. When EMF was administered to L6 cells, there was an increase in glucose transporter type 4 (GLUT4) translocation activity and a significant dose-dependent enhancement of glucose uptake by L6 myotubes. EMF treatment led to a marked increase in P-AMPK levels and GLUT4 expression in the cells, but these effects were reversed by an AMPK inhibitor (Compound C). In diabetic mice with STZ-HFD-induced diabetes, EMF treatment improved oral glucose tolerance, hyperglycemia, and hyperinsulinemia. Furthermore, EMF supplementation significantly reduced insulin resistance (IR) in diabetic mice, as evaluated using a steady-state model of the insulin resistance index. Histopathological sections demonstrated that acute EMF treatment reduced hepatic steatosis, pancreatic damage, and adipocyte hypertrophy. Western blot analysis demonstrated that EMF treatment also reduced abnormally high PPARγ expression, elevated the level of p-AMPK and p-ACC, and augmented the abundance of GLUT4 in insulin-sensitive peripheral tissues.

SUMMARY

The results suggest that EMF may exert beneficial effects on T2DM through the AMPK/GLUT4 and AMPK/ACC pathways, as well as by regulating PPARγ expression.

Impact of cyanidin 3-O-glucoside on rat micro-and systemic circulation, possibly thorough angiogenesis

Cyanidin 3-O-glucoside (C3G), an antioxidant, is one of the most abundant anthocyanin in plant foods. Intervention trials and subsequent meta-analyses have suggested that anthocyanins could reduce the risks of cardiovascular diseases. This study investigated hemodynamic alterations following a single intragastric dose of C3G by measuring blood flow in rat cremaster muscle arteriole for 60 min. Next, in excised aortas, we performed western blotting to measure the phosphorylation of Akt and endothelial nitric oxide synthase (eNOS). A single oral dose of C3G significantly increased blood flow soon after ingestion, and it was maintained throughout the experimental period. In addition, aortic Akt phosphorylation increased. Then, we examined the impact of repeated oral administrations of C3G for 14 days. The mean blood pressure was significantly reduced at 7 and 14 days after treatment, with a slight increase in aortic eNOS expression. Immunohistochemical analyses of the soleus showed that the level of CD31, an angiogenesis-marker protein, was significantly increased with C3G. These results suggested that an oral dose of C3G increased blood flow, which promoted angiogenesis within skeletal muscle, and consequently, blood pressure was reduced.

Biotechnological Approach to Increase Oxyresveratrol Production in Mulberry In Vitro Plants under Elicitation

Morus alba L. is used for a range of therapeutic purposes in Asian traditional medicine, and its extracts are reported to be effective against lipidemia, diabetes, and obesity, as well as being hepatoprotective and tyrosinase-inhibitory. They are also included in cosmetic products as anti-aging and skin-whitening agents. Stilbenes, the major bioactive compounds found in M. alba, have received renewed attention recently because of their putative activity against COVID-19. In this study M. alba plants were established in vitro, and the effect of elicitation on plant growth and stilbene accumulation, specifically oxyresveratrol and trans-resveratrol, was investigated. Different concentrations of the elicitors including methyl jasmonate and cyclodextrins were applied, and stilbene levels were determined in leaves, roots, and the culture medium. Elicitation of the M. alba plants with 5 mM cyclodextrins, alone or in combination with 10 µM methyl jasmonate, significantly increased the total phenolic content in the culture medium and leaves after 7 days of treatment. The higher total phenolic content in the roots of control plants and those treated only with methyl jasmonate indicated that cyclodextrins promoted metabolite release to the culture medium. Notably, the cyclodextrin-treated plants with the highest levels of oxy- and trans-resveratrol also had the highest total phenolic content and antioxidant capacity. These results indicate that elicited M. alba in vitro plants constitute a promising alternative source of bioactive stilbenes to supply pharmaceutical and cosmeceutical industries.

Anthocyanins as Promising Molecules Affecting Energy Homeostasis, Inflammation, and Gut Microbiota in Type 2 Diabetes with Special Reference to Impact of Acylation

Anthocyanins, the red-orange to blue-violet colorants present in fruits, vegetables, and tubers, have antidiabetic properties expressed via modulating energy metabolism, inflammation, and gut microbiota. Acylation of the glycosyl moieties of anthocyanins alters the physicochemical properties of anthocyanins and improves their stability. Thus, acylated anthocyanins with probiotic-like property and lower bioavailability are likely to have different biological effects from nonacylated anthocyanins on diabetes. This work highlights recent findings on the antidiabetic effects of acylated anthocyanins from the perspectives of energy metabolism, inflammation, and gut microbiota compared to the nonacylated anthocyanins and particularly emphasizes the cellular and molecular mechanisms associated with the beneficial effects of these bioactive molecules, providing a new perspective to explore the different biological effects induced by structurally different anthocyanins. Acylated anthocyanins may have greater modulating effects on energy metabolism, inflammation, and gut microbiota in type 2 diabetes compared to nonacylated anthocyanins.

Impact of mulberry consumption on cardiometabolic risk factors: A systematic review and meta-analysis of randomized-controlled trials

OBJECTIVE

The current study aimed to comprehensively evaluate the potential effects of mulberry consumption on cardiometabolic risk factors in adults.

METHODS

Relevant articles published up to January 2021 were systematically retrieved from SCOPUS, PubMed/MEDLINE, EMBASE, and Web of Science databases. We included all randomized controlled trials (RCTs) investigating the impact of mulberry consumption on various cardiometabolic risk factors.

RESULTS

The quantitative meta-analysis of 12 eligible RCTs demonstrated a significant reducing effect of mulberry consumption on haemoglobin A1c (HbA1c) (weighted mean difference [WMD]: -0. 55, 95% CI: -1.08, -0.02, p = 0.044), serum total cholesterol (TC) (WMD: -13.13 mg/dl, 95% CI: -19.06, -7.20, p < 0.001), low-density lipoprotein levels (LDL-C) (WMD: -8.84 mg/dl, 95% CI: -13.26, -4.42, p < 0.001), triglycerides (TG) (WMD: -19.67 mg/dl, 95% CI: -30.13, -9.22, p < 0.001) and C-reactive protein (CRP) (WMD: -1.60, mg/L, 95% CI: -3.07, -0.12, p = 0.034). Also, >300 mg daily intake of mulberry exhibited a favourable effect on serum high-density lipoprotein levels (HDL-C). However, there were no significant differences between mulberry intervention and control groups for other factors.

CONCLUSION

The current systematic review and meta-analysis revealed that incorporating mulberry into the diet may favourably affect several cardiometabolic risk factors.

A Critical Review on Role of Available Synthetic Drugs and Phytochemicals in Insulin Resistance Treatment by Targeting PTP1B

Insulin resistance (IR) is a condition of impaired response of cells towards insulin. It is marked by excessive blood glucose, dysregulated insulin signalling, altered pathways, damaged pancreatic β-cells, metabolic disorders, etc. Chronic hyperglycemic conditions leads to type 2 diabetes mellitus (T2DM) which causes excess generation of highly reactive free radicals, causing oxidative stress, further leading to development and progression of complications like vascular dysfunction, damaged cellular proteins, and DNA. One of the causes for IR is dysregulation of protein tyrosine phosphatase 1B (PTP1B). Advancements in drug therapeutics have helped people manage IR by regulating PTP1B, however have been reported to cause side effects. Therefore, there is a growing interest on usage of phytochemical constituents having IR therapeutic properties and aiding to minimize these complications. Medicinal plants have not been utilized to their full potential as a therapeutic drug due to lack of knowledge of their active and effective chemical constituents, mode of action, regulation of IR parameters, and dosage of administration. This review highlights phytochemical constituents present in medicinal plants or spices, their potential effectiveness on proteins (PTP1B) regulating IR, and reported possible mechanism of action studied on in vitro models. The study gives current knowledge and future recommendations on the above aspects and is expected to be beneficial in developing herbal drug using these phytochemical constituents, either alone or in combination, for medication of IR and diabetes.

The Potential Roles of Dietary Anthocyanins in Inhibiting Vascular Endothelial Cell Senescence and Preventing Cardiovascular Diseases

Cardiovascular disease (CVD) is a group of diseases affecting the heart and blood vessels and is the leading cause of morbidity and mortality worldwide. Increasingly more evidence has shown that the senescence of vascular endothelial cells is the key to endothelial dysfunction and cardiovascular diseases. Anthocyanin is a type of water-soluble polyphenol pigment and secondary metabolite of plant-based food widely existing in fruits and vegetables. The gut microbiome is involved in the metabolism of anthocyanins and mediates the biological activities of anthocyanins and their metabolites, while anthocyanins also regulate the growth of specific bacteria in the microbiota and promote the proliferation of healthy anaerobic flora. Accumulating studies have shown that anthocyanins have antioxidant, anti-inflammatory, and anti-aging effects. Many animal and in vitro experiments have also proven that anthocyanins have protective effects on cardiovascular-disease-related dysfunction. However, the molecular mechanism of anthocyanin in eliminating aging endothelial cells and preventing cardiovascular diseases is very complex and is not fully understood. In this systematic review, we summarize the metabolism and activities of anthocyanins, as well as their effects on scavenging senescent cells and cardioprotection.

Hypoglycemic bioactivity of anthocyanins: A review on proposed targets and potential signaling pathways

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease with complicated interrelationships responsible for initiating its pathogenesis. Novel strategies for the treatment of this devastating disease have attracted increasing attention worldwide. Anthocyanins are bioactive compounds that are widely distributed in the plant kingdom, and multiple studies have elucidated their beneficial role in preventing and managing T2DM. This review summarizes and comments on the hypoglycemic actions of anthocyanins from the perspective of molecular mechanisms and different target-related signaling pathways in vitro, in vivo, and clinical trials. Anthocyanins can ameliorate T2DM by functioning as carbohydrate digestive enzyme inhibitors, facilitating glucose transporter 4 (GLUT4) translocation, suppressing the effectiveness of dipeptidyl peptidase IV (DPP-IV), promoting glucagon-like peptide-1 (GLP-1) secretion, inhibiting protein tyrosine phosphatase 1B (PTP1B) overexpression, and interacting with sodium-glucose co-transporter (SGLT) to delay glucose absorption in various organs and tissues. In summary, anthocyanin is a promising and practical small molecule that can hyperglycemic symptoms and accompanying complications suffered by patients with diabetes. However, rational and potent doses for daily intake and clinical studies are required in the future.

Nutrition in the management of type 2 diabetes mellitus: review

Type 2 diabetes mellitus (T2DM) is the most prevalent disease and becoming a serious public health threat worldwide. In recent years, numerous effective T2DM intervention regimens have been developed, with promising results. However, these regimens are not usually economically available, and they are not well tolerated due to treatment-related toxicities. The focus nowadays is to identify new effective therapeutic agents, with relatively low cost and low toxicity, which can be used regularly to control a progression of T2DM in the prediabetic population. Accordingly, there has been growing attention in herbal remedies that can be presented into the general population with the tiniest side effects and the maximal preventive outcome. This article reviews recent publications in experimental models of T2DM not revised before, and supporting the potential use of nutraceuticals and phytochemicals through different mechanisms with promising results in the context of T2DM.

Dietary Antioxidant Anthocyanins Mitigate Type II Diabetes through Improving the Disorder of Glycometabolism and Insulin Resistance

Insulin resistance (IR) is one of the pathological reasons for type II diabetes mellitus (T2DM). Therefore, it is important to prevent the body from developing T2DM by improving IR and maintaining glucose homeostasis. Anthocyanins (ACNs) are water-soluble pigments and are widely distributed in natural products. This article summarizes research on the bioavailability and metabolism of ACNs. Moreover, we further elaborate on how ACNs reduce IR and hyperglycemia during the development of T2DM based on studies over the past 20 years. Many studies have demonstrated that ACNs are small molecules that target the pancreatic, liver, muscle, and adipose tissues, preventing IR and hyperglycemia. However, the molecular mechanisms are still unclear. Therefore, we envision whether the molecular mechanism of reducing T2DM by ACNs could be more deeply investigated.

Mori Ramulus Suppresses Hydrogen Peroxide-Induced Oxidative Damage in Murine Myoblast C2C12 Cells through Activation of AMPK

Mori Ramulus, the dried twigs of Morus alba L., has been attracting attention for its potent antioxidant activity, but its role in muscle cells has not yet been elucidated. The purpose of this study was to evaluate the protective effect of aqueous extracts of Mori Ramulus (AEMR) against oxidative stress caused by hydrogen peroxide (H₂O₂) in C2C12 mouse myoblasts, and in dexamethasone (DEX)-induced muscle atrophied models. Our results showed that AEMR rescued H₂O₂-induced cell viability loss and the collapse of the mitochondria membrane potential. AEMR was also able to activate AMP-activated protein kinase (AMPK) in H₂O₂-treated C2C12 cells, whereas compound C, a pharmacological inhibitor of AMPK, blocked the protective effects of AEMR. In addition, H₂O₂-triggered DNA damage was markedly attenuated in the presence of AEMR, which was associated with the inhibition of reactive oxygen species (ROS) generation. Further studies showed that AEMR inhibited cytochrome c release from mitochondria into the cytoplasm, and Bcl-2 suppression and Bax activation induced by H₂O₂. Furthermore, AEMR diminished H₂O₂-induced activation of caspase-3, which was associated with the ability of AEMR to block the degradation of poly (ADP-ribose) polymerase, thereby attenuating H₂O₂-induced apoptosis. However, compound C greatly abolished the protective effect of AEMR against H₂O₂-induced C2C12 cell apoptosis, including the restoration of mitochondrial dysfunction. Taken together, these results demonstrate that AEMR could protect C2C12 myoblasts from oxidative damage by maintaining mitochondrial function while eliminating ROS, at least with activation of the AMPK signaling pathway. In addition, oral administration of AEMR alleviated gastrocnemius and soleus muscle loss in DEX-induced muscle atrophied rats. Our findings support that AEMR might be a promising therapeutic candidate for treating oxidative stress-mediated myoblast injury and muscle atrophy.

Mulberry (Morus alba L.) Fruit Extract Ameliorates Inflammation via Regulating MicroRNA-21/132/143 Expression and Increases the Skeletal Muscle Mitochondrial Content and AMPK/SIRT Activities

The Mulberry (Morus alba L.) fruit is a rich source of polyphenolic compounds; most of these are anthocyanins. Obesity is intimately related to low-grade inflammation, with increased pro-inflammatory cytokine secretion and macrophage infiltration in white adipose tissue (WAT). This study investigated whether mulberry fruit extract (ME) has beneficial effects on obesity-induced inflammation and skeletal muscle mitochondrial dysfunction. Sprague-Dawley rats were divided into four groups and fed either a low-fat diet (LFD), high-fat diet (HFD), HFD + 5 g/kg of ME (ME-L), or HFD + 10 g/kg of ME (ME-H) for 14 weeks. ME alleviated dyslipidemia and lipid accumulation, as well as pro-inflammatory cytokine production such as tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), and monocyte chemoattractant protein 1 (MCP1) in the WAT. ME mitigated nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) phosphorylation and macrophage infiltration in WAT. Notably, microRNA (miR)-21, miR-132, and miR-43 expressions were downregulated in the WAT of the ME groups compared to the HFD group. Moreover, ME increased the mitochondrial size and mitochondrial DNA (mtDNA) content, as well as key genes’ expression related to mitochondrial function, including sirtuin (SIRT)1, peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), carnitine palmitoyltransferase 1β (CPT-1β), and uncoupling protein 3 (UCP3), and adenosine monophosphate-activated protein kinase (AMPK)/SIRT activities in skeletal muscle. These results suggested that ME might alleviate obesity-induced inflammation and mitochondrial dysfunction by regulating miR-21, miR-132, and miR-43 expression in WAT, and by activating the PGC-1α/SIRT1 pathway in muscle.

Pharmacological Activities for Morus alba L., Focusing on the Immunostimulatory Property from the Fruit Aqueous Extract

Depending on the extraction method, numerous compounds that have specific pharmacological effects can be obtained from M. alba L. There is a growing scientific interest in health problems related to aging. Efforts to develop safe immune-enhancing pharmaceuticals are increasing. This review aims to summarize and critically discuss the immunity enhancement effects and pharmaceutical efficacy of M. alba L. extracts. The scientific database search was conducted using Google Scholar, Web of Science, and PubMed until May 2021. Additional articles were identified and obtained from references in the retrieved articles. Ethanol or methanol extraction of various parts of M. alba L. identified a large amount of phenols and flavonoids, which are effective for immunosuppression, antioxidants, and cardiovascular diseases, and are antibacterial, and anticancer. Water extraction of M. alba L. enhanced the innate immune response based on immune cell activation. A polysaccharide and an alkaloid related to increased macrophage activity were isolated from M. alba L. fruit extracts. M. alba L. fruit water extracts primarily induced the production of pro-inflammatory substances, in model organisms, via TLR4 in immune cells. Water extracts have been shown to be effective in pathogen defense and tumor suppression by enhancing macrophage activity. Based on our literature review on the bioactivity of M. alba L. fruit extracts, particularly in relation to their immunity enhancement activity, we anticipate that M. alba-derived pharmaceuticals will have excellent potential in future medical research.

Metabolic functions of flavonoids: From human epidemiology to molecular mechanism

Dietary flavonoid intake is associated with the regulation of nutrient metabolism in the living body. Observational and cohort studies have reported a negative association between flavonoid intake and the risk of metabolic and cardiovascular diseases. Several intervention trials in humans have also supported the benefits of dietary flavonoids. In experimental studies using animal models, a daily diet rich in typical flavonoids such as catechins, anthocyanin, isoflavone, and quercetin was shown to improve whole-body energy expenditure, mitochondrial activity, and glucose tolerance. For some flavonoids, molecular targets for the metabolic modulations have been suggested. Although the effect of flavonoids on neurons has been unclear, several flavonoids have been shown to regulate thermogenesis and feeding behavior through modulating autonomic and central nervous systems. Based on epidemiological and experimental studies, this review summarizes the evidence on the metabolic benefits of flavonoids and their potential mechanism of action in metabolic regulation.

Identification of bioactive compounds from mulberry enhancing glucose-stimulated insulin secretion

Previously, we isolated six heterocyclic compounds (1-6) from the fruits of mulberry trees (Morus alba L.) and determined that loliolide affords rat pancreatic islet β-cell (INS-1) protection against streptozotocin‑induced cytotoxicity. In the present study, we further investigated the effect of the six heterocyclic compounds (1-6) on glucose-stimulated insulin secretion (GSIS) in INS-1 cells. Among them, (R)‑5‑hydroxypyrrolidin‑2‑one(1) and indole (6) increased GSIS without inducing cytotoxicity. Additionally, compounds 1 and 6 enhanced the phosphorylation of total insulin receptor substrate-2, phosphatidylinositol 3-kinase, and Akt, and activated pancreatic and duodenal homeobox-1, which play a crucial role in β-cell functions related to insulin secretion. Collectively, these findings indicate that (R)‑5‑hydroxypyrrolidin‑2‑one(1) and indole (6), isolated from M. alba fruits, may be beneficial in managing type 2 diabetes.

Lyophilized Maqui (Aristotelia chilensis) Berry Administration Suppresses High-Fat Diet-Induced Liver Lipogenesis through the Induction of the Nuclear Corepressor SMILE

The liver is one of the first organs affected by accumulated ectopic lipids. Increased de novo lipogenesis and excessive triglyceride accumulation in the liver are hallmarks of nonalcoholic fatty liver disease (NAFLD) and are strongly associated with obesity, insulin resistance, and type 2 diabetes. Maqui dietary supplemented diet-induced obese mice showed better insulin response and decreased weight gain. We previously described that these positive effects of maqui are partially due to an induction of a brown-like phenotype in subcutaneous white adipose tissue that correlated with a differential expression of Chrebp target genes. In this work, we aimed to deepen the molecular mechanisms underlying the impact of maqui on the onset and development of the obese phenotype and insulin resistance focusing on liver metabolism. Our results showed that maqui supplementation decreased hepatic steatosis caused by a high-fat diet. Changes in the metabolic profile include a downregulation of the lipogenic liver X receptor (LXR) target genes and of fatty acid oxidation gene expression together with an increase in the expression of small heterodimer partner interacting leucine zipper protein (Smile), a corepressor of the nuclear receptor family. Our data suggest that maqui supplementation regulates lipid handling in liver to counteract the metabolic impact of a high-fat diet.

Morus alba L. Plant: Bioactive Compounds and Potential as a Functional Food Ingredient

Morus alba L. (M. alba) is a highly adaptable plant that is extensively incorporated in many traditional and Ayurveda medications. Various parts of the plant, such as leaves, fruits, and seeds, possess nutritional and medicinal value. M. alba has abundant phytochemicals, including phenolic acids, flavonoids, flavonols, anthocyanins, macronutrients, vitamins, minerals, and volatile aromatic compounds, indicating its excellent pharmacological abilities. M. alba also contains high nutraceutical values for protein, carbohydrates, fiber, organic acids, vitamins, and minerals, as well as a low lipid value. However, despite its excellent biological properties and nutritional value, M. alba has not been fully considered as a potential functional food ingredient. Therefore, this review reports on the nutrients and bioactive compounds available in M. alba leaves, fruit, and seeds; its nutraceutical properties, functional properties as an ingredient in foodstuffs, and a microencapsulation technique to enhance polyphenol stability. Finally, as scaling up to a bigger production plant is needed to accommodate industrial demand, the study and limitation on an M. alba upscaling process is reviewed.

Dietary anthocyanins as potential natural modulators for the prevention and treatment of non-alcoholic fatty liver disease: A comprehensive review

Nonalcoholic fatty liver disease (NAFLD) refers to a metabolic syndrome linked with type 2 diabetes mellitus, obesity, and cardiovascular diseases. It is characterized by the accumulation of triglycerides in the hepatocytes in the absence of alcohol consumption. The prevalence of NAFLD has abruptly increased worldwide, with no effective treatment yet available. Anthocyanins (ACNs) belong to the flavonoid subclass of polyphenols, are commonly present in various edible plants, and possess a broad array of health-promoting properties. ACNs have been shown to have strong potential to combat NAFLD. We critically assessed the literature regarding the pharmacological mechanisms and biopharmaceutical features of the action of ACNs on NAFLD in humans and animal models. We found that ACNs ameliorate NAFLD by improving lipid and glucose metabolism, increasing antioxidant and anti-inflammatory activities, and regulating gut microbiota dysbiosis. In conclusion, ACNs have potential to attenuate NAFLD. However, further mechanistic studies are required to confirm these beneficial impacts of ACNs on NAFLD.

Plant Extracts for Type 2 Diabetes: From Traditional Medicine to Modern Drug Discovery

Type 2 diabetes mellitus (T2DM) is one of the largest public health problems worldwide. Insulin resistance-related metabolic dysfunction and chronic hyperglycemia result in devastating complications and poor prognosis. Even though there are many conventional drugs such as metformin (MET), Thiazolidinediones (TZDs), sulfonylureas (SUF), dipeptidyl peptidase 4 (DPP-4) inhibitors, glucagon like peptide 1 (GLP-1) and sodium-glucose cotransporter-2 (SGLT-2) inhibitors, side effects still exist. As numerous plant extracts with antidiabetic effects have been widely reported, they have the potential to be a great therapeutic agent for type 2 diabetes with less side effects. In this study, sixty-five recent studies regarding plant extracts that alleviate type 2 diabetes were reviewed. Plant extracts regulated blood glucose through the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) pathway. The anti-inflammatory and antioxidant properties of plant extracts suppressed c-Jun amino terminal kinase (JNK) and nuclear factor kappa B (NF-κB) pathways, which induce insulin resistance. Lipogenesis and fatty acid oxidation, which are also associated with insulin resistance, are regulated by AMP-activated protein kinase (AMPK) activation. This review focuses on discovering plant extracts that alleviate type 2 diabetes and exploring its therapeutic mechanisms.

New model in diabetic mice to evaluate the effects of insulin therapy on biofilm development in wounds

Objective: Diabetic patients suffer more frequently from biofilm-associated infections than normoglycemic patients. Well described in the literature is a relationship between elevated blood glucose levels in patients and the occurrence of biofilm-associated wound infections. Nevertheless, the underlying pathophysiological pathways leading to this increased infection vulnerability and its effects on biofilm development still need to be elucidated. We developed in our laboratory a model to allow the investigation of a biofilm-associated wound infection in diabetic mice under controlled insulin treatment.

Methods: A dorsal skinfold chamber was used on 16 weeks old BKS.Cg-Dock7^m +/+ Lepr^db/J mice and a wound within the observation field of the dorsal skinfold chamber was created. These wounds were infected with Staphylococcus aureus ATCC 49230 (10⁶ cells/mL). Simultaneously, we implanted implants for sustained insulin release into the ventral subcutaneous tissue (N=5 mice). Mice of the control group (N=5) were treated with sham implants.

Serum glucose levels were registered before intervention and daily after the operation. Densitometrical analysis of the wound size was performed at day 0, 3, and 6 after intervention. Mice were sacrificed on day 6 and wound tissue was submitted to fluorescence in situ hybridization (FISH) and colony forming unit (CFU) analysis in addition to immunohistochemical staining to observe wound healing.

Experiments were carried out in accordance with the National Institute of Health Guidelines for the Care and Use of Laboratory Animals (protocol number 05/19).

Results: The insulin implants were able to reduce blood glucose levels in the mice. Hence, the diabetic mice in the intervention group were normoglycemic after the implantation. The combination with the dorsal skinfold chamber allowed for continuous, in vivo measurements of the infection development. Implantation of the insulin implant and the dorsal skinfold chamber was a tolerable condition for the diabetic mice. We succeeded to realize reproducible biofilm infections in the animals.

Discussion: We developed a novel model to assess interactions between blood glucose level and S. aureus-induced biofilm-associated wound infections.

The combination of the dorsal skinfold chamber model with a sustained insulin treatment has not been described so far. It allows a broad field of glucose and insulin dependent studies of infection.

Anthocyanin Bioactivity in Obesity and Diabetes: The Essential Role of Glucose Transporters in the Gut and Periphery

Obesity and type-2 diabetes trends continue to worsen in the United States. Dietary anthocyanins (typically provided by berries and other fruits) are reported to have protective effects against both conditions using a variety of experimental research models including animal and human feeding studies. This review highlights studies that explore the biochemical pathways in both tissue and rodent models which could explain clinical improvements noted with anthocyanin consumption. First, the primary mode of intestinal absorption of anthocyanins is through both sGLT1 and GLUT2 glucose transporters. Stronger binding affinities may allow anthocyanins to be more inhibitive to glucose absorption compared to the reverse, where GLUT2 expression may also be affected. Genetic or chemical inhibition of sGLT1 or GLUT2 demonstrate their essential function in anthocyanin absorption across the enterocyte, where the former interacts with a greater variety of anthocyanins but the latter is the major transporter for specific anthocyanin-glycosides. Once absorbed, anthocyanins positively modulate GLUT4 density and function in both skeletal muscle and adipose tissues via the upregulation of AMPK and restoration of insulin sensitivity. Antioxidant properties and phosphodiesterase inhibition by anthocyanins promote both mitochondrial function and density which could be novel targets for dietary management of obesity and its complications.

Metabolic Impact of Flavonoids Consumption in Obesity: From Central to Peripheral

The prevention and treatment of obesity is primary based on the follow-up of a healthy lifestyle, which includes a healthy diet with an important presence of bioactive compounds such as polyphenols. For many years, the health benefits of polyphenols have been attributed to their anti-oxidant capacity as free radical scavengers. More recently it has been described that polyphenols activate other cell-signaling pathways that are not related to ROS production but rather involved in metabolic regulation. In this review, we have summarized the current knowledge in this field by focusing on the metabolic effects of flavonoids. Flavonoids are widely distributed in the plant kingdom where they are used for growing and defensing. They are structurally characterized by two benzene rings and a heterocyclic pyrone ring and based on the oxidation and saturation status of the heterocyclic ring flavonoids are grouped in seven different subclasses. The present work is focused on describing the molecular mechanisms underlying the metabolic impact of flavonoids in obesity and obesity-related diseases. We described the effects of each group of flavonoids in liver, white and brown adipose tissue and central nervous system and the metabolic and signaling pathways involved on them.

Phytosome Loading the Combined Extract of Mulberry Fruit and Ginger Protects against Cerebral Ischemia in Metabolic Syndrome Rats

The prevalence of ischemic stroke in metabolic syndrome (MetS) is continually increasing and produces a great impact on both qualities of life and annual healthcare budget. Due to the efficiency limitation of the current therapeutic strategy, the poor availability of polyphenol substances induced by the first pass effect and the beneficial effects of mulberry fruit and ginger on brain and MetS-related diseases together with the synergistic concept, the neuroprotective effect against ischemic stroke in MetS condition of phytosome containing the combined extract of mulberry fruit and ginger (PMG) has been considered. To explore the neuroprotective effect and possible underlying mechanism of PMG on brain damage in cerebral ischemic rat with MetS, male Wistar rats were induced MetS by high-carbohydrate high-fat diet (HCHF) for 16 weeks and subjected to the cerebral ischemia/reperfusion injury (CIRI) at the right middle cerebral artery (Rt. MCAO). PMG at doses of 50, 100, and 200 mg/kg were orally fed with for 21 days, and they were assessed brain damage, neurological deficit score, and the changes of oxidative stress markers, inflammatory markers, PPARγ expression, and epigenetic modification via DNMT-1 were performed. All doses of PMG significantly improved brain infarction, brain edema, and neurological deficit score. In addition, the reduction in DNMT-1, MDA level, NF-κB, TNFα, and C-reactive protein together with the increase in SOD, CAT, and GPH-Px activities, and PPARγ expression in the lesion brain were also observed. The current data clearly revealed the neuroprotective effect against cerebral ischemia with MetS condition. The possible underlying mechanism might occur partly via the suppression of DNMT-1 giving rise to the improvement of signal transduction via PPARγ resulting in the decreasing of inflammation and oxidative stress. In conclusion, PMG is the potential neuroprotectant candidate against ischemic stroke in the MetS condition. However, the clinical trial is still essential.

The Role of Helicobacter pylori and Serum Pepsinogen Levels in Metachronous Gastric Cancer After Endoscopic Gastrectomy

PURPOSE

The current study aimed to explore the role of Helicobacter pylori (Hp) infection and serum pepsinogen (PG) levels in the occurrence of metachronous gastric cancer after endoscopic gastrectomy.

MATERIALS AND METHODS

Totally, 50 patients with metachronous gastric cancer, 50 patients with chronic atrophic gastritis and 50 healthy subjects were collected from October 2015 to October 2018. Patients in the gastric cancer group underwent endoscopic gastrectomy. Serum samples were collected for detection and correlation analysis of serum PG I, PG II, and Hp. In addition, the contents of serum PG and gastrin and postoperative adverse events were statistically analyzed.

RESULTS

There was a statistically significant difference in serum PG I levels, positive Hp infection rate, the number of mast cells, plasma motilin levels and postoperative adverse events among the 3 groups (P<0.01). There was also a significant difference in PG II levels among the groups (P<0.05). On the basis of the results, the amount of inflammatory cells in the gastric cancer group was significantly higher than that in the gastritis group, and there was a remarkable difference in gastric cancer patients before and after operation. Through data analysis, it was found that the levels of PG I and II were the highest in the healthy control group and the lowest in the gastric cancer group, the number of mast cells was the largest in the gastric cancer group, and the level of motilin was the highest in the healthy control group.

CONCLUSION

Hp infection and serum PG levels are associated with metachronous gastric cancer.

The role of anthocyanins as antidiabetic agents: from molecular mechanisms to in vivo and human studies

Diabetes mellitus is a chronic metabolic disease characterized by high blood glucose concentration. Nowadays, type 2 diabetes or insulin resistant diabetes is the most common diabetes, mainly due to unhealthy lifestyle. Healthy habits like appropriate nutritional approaches or the consumption of certain natural products or food supplements have been suggested as non-pharmacological strategies for the treatment and prevention of type 2 diabetes. Some of the main bioactive compounds from plant foods are polyphenols, important mainly for their antioxidant capacity in oxidative stress conditions and ageing. Anthocyanins are polyphenols of the flavonoid group, which act as pigments in plants, especially in fruits such as berries. A search of in vitro, in vivo and human studies in relation with antidiabetic properties of anthocyanins has been performed in different electronic databases. Results of this review demonstrate that these compounds have the ability to inhibit different enzymes as well as to influence gene expression and metabolic pathways of glucose, such as AMPK, being able to modulate diabetes and other associated disorders, as hyperlipidaemia, overweight, obesity and cardiovascular diseases. Additionally, human interventional studies have shown that high doses of anthocyanins have potential in the prevention or treatment of type 2 diabetes; nevertheless, anthocyanins used in these studies should be standardized and quantified in order to make general conclusions about its use and to claim benefits for the human population.

Mulberry Fruit Extract Promotes Serum HDL-Cholesterol Levels and Suppresses Hepatic microRNA-33 Expression in Rats Fed High Cholesterol/Cholic Acid Diet

Serum high-density lipoprotein cholesterol (HDL-C) levels and cholesterol excretion are closely associated with the risk of cardiovascular complications. The specific aim of the present study was to investigate the cholesterol lowering effect of mulberry fruit in rats fed a high cholesterol/cholic acid diet. Four-week supplementation with mulberry fruit extract significantly decreased serum and hepatic cholesterol (TC), serum low-density lipoprotein cholesterol (LDL-C), and fecal bile acid levels without changes in body weight and food intake (p < 0.05). Mulberry fruit extract significantly inhibited hepatic sterol-regulatory element binding protein (Srebp) 2 gene expression and upregulated hepatic mRNA levels of liver X receptor alpha (Lxr-α), ATP-binding cassette transporter 5 (Abcg5), and cholesterol 7 alpha-hydroxylase (Cyp7a1), which are involved in hepatic bile acid synthesis and cholesterol metabolism (p < 0.05). In addition, hepatic microRNA-33 expression was significantly inhibited by supplementation of mulberry fruit extract (p < 0.05). These results suggest the involvement of miR-33, its associated hepatic bile acid synthesis, HDL formation, and cholesterol metabolism in mulberry fruit-mediated beneficial effects on serum and hepatic lipid abnormalities.

The Colors of Health: Chemistry, Bioactivity, and Market Demand for Colorful Foods and Natural Food Sources of Colorants

There is an increasing consumer demand for natural colors in foods. However, there is a limited number of available natural food sources for use by the food industry because of technical and regulatory limitations. Natural colors are less stable and have less vibrant hues compared to their synthetic color counterparts. Natural pigments also have known health benefits that are seldom leveraged by the food industry. Betalains, carotenoids, phycocyanins, and anthocyanins are major food colorants used in the food industry that have documented biological effects, particularly in the prevention and management of chronic diseases such as diabetes, obesity, and cardiovascular disease. The color industry needs new sources of stable, functional, and safe natural food colorants. New opportunities include sourcing new colors from microbial sources and via the use of genetic biotechnology. In all cases, there is an imperative need for toxicological evaluation to pave the way for their regulatory approval.

Mulberry Fruit Extract Ameliorates Adipogenesis via Increasing AMPK Activity and Downregulating MicroRNA-21/143 in 3T3-L1 Adipocytes

Mulberry (Morus alba L.) fruits have long been used in traditional medicine and as edible berries in many countries. This study investigated the antiadipogenic effect of high hydrostatic pressure mulberry fruit extract (MFE) during 3T3-L1 adipocyte differentiation. MFE decreased lipid and triglyceride accumulation and glycerol-3-phosphate dehydrogenase activity. The mRNA expression levels of genes related to adipogenesis, such as the adipocyte protein 2, proliferator-activated receptor-γ, and CCAAT/enhancer binding protein-α, were suppressed by MFE. They also reduced microRNA (miR)-21 and miR-143 expression, which are involved in adipogenesis. In contrast, adenosine monophosphate-activated protein kinase (AMPK) activity was increased by MFE. These results suggested that MFE may suppress adipogenesis through modulating miR-21/143 expression and AMPK activity in 3T3-L1 adipocytes, which may be useful as antiobesity food agents.

A Comprehensive Review on Preclinical Diabetic Models

BACKGROUND

Preclinical experimental models historically play a critical role in the exploration and characterization of disease pathophysiology. Further, these in-vivo and in-vitro preclinical experiments help in target identification, evaluation of novel therapeutic agents and validation of treatments.

INTRODUCTION

Diabetes mellitus (DM) is a multifaceted metabolic disorder of multidimensional aetiologies with the cardinal feature of chronic hyperglycemia. To avoid or minimize late complications of diabetes and related costs, primary prevention and early treatment are therefore necessary. Due to its chronic manifestations, new treatment strategies need to be developed, because of the limited effectiveness of the current therapies.

METHODS

The study included electronic databases such as Pubmed, Web of Science and Scopus. The datasets were searched for entries of studies up to June, 2018.

RESULTS

A large number of in-vivo and in-vitro models have been presented for evaluating the mechanism of anti-hyperglycaemic effect of drugs in hormone-, chemically-, pathogen-induced animal models of diabetes mellitus. The advantages and limitations of each model have also been addressed in this review.

CONCLUSION

This review encompasses the wide pathophysiological and molecular mechanisms associated with diabetes, particularly focusing on the challenges associated with the evaluation and predictive validation of these models as ideal animal models for preclinical assessments and discovering new drugs and therapeutic agents for translational application in humans. This review may further contribute to discover a novel drug to treat diabetes more efficaciously with minimum or no side effects. Furthermore, it also highlights ongoing research and considers the future perspectives in the field of diabetes.

Effect of Anthocyanin-Rich Tart Cherry Extract on Inflammatory Mediators and Adipokines Involved in Type 2 Diabetes in a High Fat Diet Induced Obesity Mouse Model

Male C57BL/6J mice were used to determine the possible therapeutic effects of our previously described tart cherry extract in a chronic obesity mouse model on metabolic parameters, glucose tolerance, inflammatory mediators, and antioxidant capacity. The control group received standard mouse chow, and the high fat control group was switched to a high fat diet and tap water supplemented with 5% sucrose. The high fat + anthocyanin group received the high fat and sucrose diet, but received the anthocyanin-rich tart cherry extract dissolved in their drinking water. After six weeks, an oral glucose tolerance test was performed, and the water-soluble antioxidant capacity (ACW), superoxide dismutase (SOD) activity, and the plasma levels of insulin, C-peptide, leptin, IL-6, MCP-1, adiponectin and resistin were measured. The high fat diet increased body weight, reduced glucose tolerance, and caused an elevation in leptin, IL-6, MCP-1, and resistin levels. Furthermore, antioxidant capacity was decreased with a significant elevation of SOD activity. Anthocyanin treatment failed to reverse the effects of the high fat diet on body weight and glucose tolerance, but significantly reduced the leptin and IL-6 levels. The tart cherry extract also made a significant enhancement in antioxidant capacity and SOD activity. Our results show that chronic anthocyanin intake has a potential to enhance redox status and alleviate inflammation associated with obesity.

Activation of AMPK by Medicinal Plants and Natural Products: Its Role in Type 2 Diabetes Mellitus

Type-2 Diabetes (T2D) is a metabolic disease characterized by permanent hyperglycemia, whose development can be prevented or delayed by using therapeutic agents and implementing lifestyle changes. Some therapeutic alternatives include regulation of glycemia through modulation of different mediators and enzymes, such as AMP-activated protein kinase (AMPK), a highly relevant cellular energy sensor for metabolic homeostasis regulation, with particular relevance in the modulation of liver and muscle insulin sensitivity. This makes it a potential therapeutic target for antidiabetic drugs. In fact, some of them are standard drugs used for treatment of T2D, such as biguanides and thiazolidindiones. In this review, we compile the principal natural products that are activators of AMPK and their effect on glucose metabolism, which could make them candidates as future antidiabetic agents. Phenolics such as flavonoids and resveratrol, alkaloids such as berberine, and some saponins are potential natural activators of AMPK with a potential future as antidiabetic drugs.

Natural Hydrogen Sulfide Donors from Allium sp. as a Nutraceutical Approach in Type 2 Diabetes Prevention and Therapy

Type 2 diabetes mellitus (DM) is a socially relevant chronic disease with high prevalence worldwide. DM may lead to several vascular, macrovascular, and microvascular complications (cerebrovascular, coronary artery, and peripheral arterial diseases, retinopathy, neuropathy, and nephropathy), often accelerating the progression of atherosclerosis. Dietary therapy is generally considered to be the first step in the treatment of diabetic patients. Among the current therapeutic options, such as insulin therapy and hypoglycemic drugs, in recent years, attention has been shifting to the effects and properties-that are still not completely known-of medicinal plants as valid and inexpensive therapeutic supports with limited side effects. In this review, we report the relevant effects of medicinal plants and nutraceuticals in diabetes. In particular, we paid attention to the organosulfur compounds (OSCs) present in plant extracts that due to their antioxidant, hypoglycemic, anti-inflammatory, and immunomodulatory effects, can contribute as cardioprotective agents in type 2 DM. OSCs derived from garlic (Allium sp.), due to their properties, can represent a valuable support to the diet in type 2 DM, as outlined in this manuscript based on both in vitro and in vivo studies. Moreover, a relevant characteristic of garlic OSCs is their ability to produce the gasotransmitter H₂S, and many of their effects can be explained by this property. Indeed, in recent years, several studies have demonstrated the relevant effects of endogenous and exogenous H₂S in human DM, including by in vitro and in vivo experiments and clinical trials; therefore, here, we summarize the effects and the underlying molecular mechanisms of H₂S and natural H₂S donors.

Encapsulated Mulberry Fruit Extract Alleviates Changes in an Animal Model of Menopause with Metabolic Syndrome

Currently, the therapeutic strategy against metabolic syndrome and its complications is required due to the increasing prevalence and its impact. Due to the benefits of both mulberry fruit extract and encapsulation technology, we hypothesized that encapsulated mulberry fruit extract (MME) could improve metabolic parameters and its complication risk in postmenopausal metabolic syndrome. To test this hypothesis, female Wistar rats were induced experimental menopause with metabolic syndrome by bilateral ovariectomy (OVX) and high-carbohydrate high-fat (HCHF) diet. Then, they were orally given MME at doses of 10, 50, and 250 mg/kg BW for 8 weeks and the parameters, such as percentage of body weight gain, total cholesterol, triglycerides, HDL-C, LDL-C, atherogenic index, fasting blood glucose, plasma glucose area under the curve, serum angiotensin-converting enzyme (ACE), oxidative stress status, histology, and protein expression of PPAR-γ, TNF-α, and NF-κB in adipose tissues were determined. MME improved body weight gain, adiposity index, glucose intolerance, lipid profiles, atherogenic index, ACE, oxidative stress status, and protein expression of TNF-α and NF-κB. Moreover, MME attenuated adipocyte hypertrophy and enhanced PPAR-γ expression. Taken altogether, MME decreased metabolic syndrome and its complication via the increased PPAR-γ expression. Therefore, MME is the potential candidate for improving metabolic syndrome and its related complications. However, further research in clinical trial is still necessary.

Anti-Inflammatory Effects of High Hydrostatic Pressure Extract of Mulberry (Morus alba) Fruit on LPS-Stimulated RAW264.7 Cells

Mulberry fruit (Morus alba L.) contains abundant bioactive compounds, including anthocyanins and flavonols, and has been reported to possess potent beneficial properties including anticancer, antidiabetic, and anti-oxidant effects. High hydrostatic pressure (HHP) processing, a nonthermal food processing technology, is suitable for the extraction of bioactive compounds from plants. Nevertheless, the anti-inflammatory effects of HHP extract of mulberry fruit (HM) in RAW264.7 cells remain unclear. The present study aimed to investigate the anti-inflammatory effects of HM on lipopolysaccharide (LPS)-induced inflammation in vitro. RAW264.7 cells were treated with various concentrations (0.1-1 μg/mL) of HM in the presence or absence of LPS. HM inhibited the inflammatory mediator, nitric oxide (NO) release, and mRNA expression of nitric oxide synthase 2 (NOS2) in LPS-induced RAW264.7 cells. In addition, HM suppressed both mRNA and protein expressions of prostaglandin-endoperoxide synthase 2 (PTGS2). Moreover, it reduced the LPS-induced secretion of proinflammatory cytokines such as interleukin (IL)-6 and tumor necrosis factor (TNF)-α. These results revealed that HM exerts anti-inflammatory effects by inhibiting several mediators and cytokines involved in the inflammatory process.

Nutraceutical and Medicinal Potential of the Morus Species in Metabolic Dysfunctions

Many populations use medicinal plants as a therapeutic treatment, due to their lower cost and greater access. Among the plant species used for medicinal purposes are those of the genus Morus. The most known species are Morus alba, rubra, and nigra. This review aims to collect data from the literature, predominantly from cell and animal studies, which presents a possible nutraceutical and medicinal potential of the species Morus for use in metabolic dysfunctions. The fruits and leaves of mulberry are used for therapeutic purposes. For scientific confirmation of these effects, they were studied for laxative properties, antibacterial activity, anti-atherogenic activity, and hepatoprotective function. Furthermore, the genus Morus is recognized for the treatment and prevention of diabetes mellitus, through its hypoglycemic action. It may also provide health benefits through immunomodulatory, anti-inflammatory, and anti-nociceptive effects. It has been found that the Morus species have phenolic compounds, flavonoids, and anthocyanins that act as important antioxidants and promote beneficial effects on human health. These phytochemical compounds differ among species. Blackberry (Morus nigra) are rich in flavonoids, while the white mulberry (Morus alba) has low concentrations of flavonoids and anthocyanins. In addition, another important factor is to ensure a complete exemption of toxic risks in the use of medicinal plants for the treatment of diseases. Studies have shown no toxic effects by the administration of extracts of Morus species. Thus, the mulberry tree presents nutraceutical potential. It is therefore a promising alternative for medicinal products based on medicinal plants.