Antidiabetic and Antioxidative Potential of the Blue Congo Variety of Purple Potato Extract in Streptozotocin-Induced Diabetic Rats

European bilberry extract reduces high-temperature baked food-induced accumulation of Nε-carboxymethyllysine and Nε-carboxyethyllysine in vivo

This study aimed to investigate the effect of European bilberry extract (EBE) on the accumulation of Nε-carboxymethyllysine (CML) and Nε-carboxyethyllysine (CEL) in rats exposed to a high advanced glycation end products (AGEs) diet. We found that EBE reduced high AGEs diet-induced accumulation of free-CML, bound-CML, free-CEL, and bound-CEL in the serum, kidney, skin, and brain. EBE also inhibited high AGEs diet-induced accumulation of bound-CML and bound-CEL in the uterus, ovary, stomach, duodenum, and colon. Meanwhile, EBE attenuated high AGEs diet-induced accumulation of free-CML and free-CEL in the muscle, bone, joint, and eyes. In addition, EBE ameliorated high AGEs diet-induced accumulation of free-CML and bound-CML in the liver, free-CML in the ovary, and bound-CML in the thyroid gland. EBE had no effect on the accumulation of free-CML, bound-CML, free-CEL, and bound-CEL in the adrenal gland and free-CML and free-CEL in the heart caused by a high AGEs diet. We did not observe AGEs accumulation in the pancreas, aorta, lung, spleen, and adipose tissues. This study revealed the in vivo distribution of CML and CEL exposed to a high AGEs diet and the effect of EBE on reducing the accumulation of CML and CEL in the specific target tissues.

Studying the Stability of Anthocyanin Pigments Isolated from Juices of Colored-Fleshed Potatoes

The aim of this study was to obtain extracts of anthocyanin pigments from red and purple-fleshed potato juices characterized by stable color. For this purpose, potato juices were pasteurized at different temperatures or fruit and vegetable concentrates were added to them. Color stability tests of the obtained pigments were carried out in model pH and temperature conditions and after adding to natural yogurt. Both the pasteurization process and the addition of fruit and vegetable concentrates to the potato juices positively affected their color and its stability in time. However, the pasteurization of the potato juices had a negative effect on the content of biologically active compounds, in contrast to the juices stabilized with the addition of fruit and vegetable concentrates. Anthocyanin pigments from red-fleshed potato juices were more stable than those isolated from the purple-fleshed potato juices. The results of model tests of the anthocyanin pigment concentrates from the colored-flesh potatoes and natural yoghurts with their addition confirmed the high stability of the tested concentrates.

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.

Purple sweet potato anthocyanins normalize the blood glucose concentration and restore the gut microbiota in mice with type 2 diabetes mellitus

Background

This study investigated the effects of purple sweet potato anthocyanins (PSPA) in a type 2 diabetes mellitus (T2DM) mouse model.

Methods

Sixty-five male mice were randomly divided into one control group and four experimental groups, which were fed with a high-fat diet and intraperitoneally injected with streptozotocin (STZ) to induce T2DM. The model mice were treated with 0 (M), 227.5 (LP), 455 (MP), or 910 (HP) mg/kg PSPA for ten days. ELISA, 16S rRNA sequencing, and hematoxylin and eosin staining were used to assess blood biochemical parameters, gut microbial composition, and liver tissue structure, respectively.

Results

The FBG concentration was significantly decreased in the LP (6.32 ± 1.05 mmol/L), MP (6.32 ± 1.05 mmol/L), and HP (5.65 ± 0.83 mmol/L) groups; the glycosylated hemoglobin levels were significantly decreased in the HP group (14.43 ± 7.12 pg/mL) compared with that in the M group (8.08 ± 1.04 mmol/L; 27.20 ± 7.72 pg/mL; P < 0.05). The PSPA treated groups also increased blood glutathione levels compared with M. PSPA significantly affected gut microbial diversity. The Firmicutes/Bacteroidetes ratio decreased by 38.9 %, 49.2 %, and 15.9 % in the LP, MP, and HP groups compared with that in the M group (0.62). The PSPAs treated groups showed an increased relative abundance of Lachnospiraceae_Clostridium, Butyricimonas, and Akkermansia and decreased abundance of nine bacterial genera, including Staphylococcus.

Conclusion

PSPA reduced blood glucose levels, increased serum antioxidant enzymes, and optimized the diversity and structure of the gut microbiota in mice with T2DM.

Exploratory review on the evidence of Andean crops with hypoglycemic effect and their bioactive components

Diabetes is a chronic disease that affects several people around the world. Some domesticated crops in South America have been reported to be a promising source of bioactive compounds with possible hypoglycemic effects. In this review we aimed to explore and synthesize the existing evidence in the scientific literature on the hypoglycemic effect of Andean crops and their bioactive components. We included different types of primary studies from three databases (Scopus, Pubmed and Web of Science) during June 2023, without restrictions, by means of controlled and uncontrolled language, according to the PICO strategy. We found 30 studies conducted between 2005 and 2022 that reported a hypoglycemic effect, through enzymatic inhibition in in vitro studies and significant glucose reduction in preclinical studies and clinical trials. This effect was attributed to different bioactive components that were identified with independent mechanisms related to glucose reduction and enzymatic inhibition. The most commonly used cultures were Smallanthus sonchifolius (9/30), Lupinus mutabilis (5/30) and Solanum tuberosum (4/30). The hypoglycemic effect was assigned to bioactive components such as polyphenols, flavonoids, phenolic acid subclasses, fructans, alkaloids, hydrolysates, anthocyanins and dietary fiber. Despite encouraging results from different types of studies, further research on their mechanisms of action, their efficacy compared to conventional treatments and their long-term safety is required for these to be considered safe and effective treatments.

Effects of Anthocyanins on Components of Metabolic Syndrome-A Review

Metabolic syndrome (MetS) is a significant health problem. The co-occurrence of obesity, carbohydrate metabolism disorders, hypertension and atherogenic dyslipidaemia is estimated to affect 20-30% of adults worldwide. Researchers are seeking solutions to prevent and treat the conditions related to MetS. Preventive medicine, which focuses on modifiable cardiovascular risk factors, including diet, plays a special role. A diet rich in fruits and vegetables has documented health benefits, mainly due to the polyphenolic compounds it contains. Anthocyanins represent a major group of polyphenols; they exhibit anti-atherosclerotic, antihypertensive, antithrombotic, anti-inflammatory and anticancer activities, as well as beneficial effects on endothelial function and oxidative stress. This review presents recent reports on the mechanisms involved in the protective effects of anthocyanins on the body, especially among people with MetS. It includes epidemiological data, in vivo and in vitro preclinical studies and clinical observational studies. Anthocyanins are effective, widely available compounds that can be used in both the prevention and treatment of MetS and its complications. Increased consumption of anthocyanin-rich foods may contribute to the maintenance of normal body weight and modulation of the lipid profile in adults. However, further investigation is needed to confirm the beneficial effects of anthocyanins on serum glucose levels, improvement in insulin sensitivity and reduction in systolic and diastolic blood pressure.

Protective role of Pleurotus florida against streptozotocin-induced hyperglycemia in rats: A preclinical study

Pleurotus florida (Mont.) Singer is a mushroom species known to be an antioxidant, immunomodulatory, and diuretic agent, reducing blood pressure and cholesterol. The aim of this study was to evaluate the in vivo potency of P. florida's anti-diabetic properties in rats affected by hyperglycemia induced by Streptozotocin (STZ) at 55 mg/kg (i.p.), characterized by oxidative stress impairment, and changes in insulin levels and lipid profile. After inducing hyperglycemia in the rats, they were treated with P. florida acetone and methanol extracts, orally administered for 28 days at doses of 200 mg/kg and 400 mg/kg body weight. The hyperglycemic control (DC) group showed significant increases (P < 0.05) in mean blood sugar, total cholesterol, triglycerides, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, blood urea nitrogen, lipid hydroperoxides, and malondialdehyde, compared to the normal control (NC) group The high-density lipoprotein cholesterol, serum insulin, superoxide dismutase, catalase, glutathione disulfide, glutathione peroxidase, reduced glutathione, guaiacol peroxidase, and vitamin E and C levels showed a significant decrease (P < 0.05) in DC group, compared to the NC group. Blood glucose levels, lipid profiles, and insulin levels improved significantly after 28 days of treatment, in the group treated with glibenclamide (an oral hypoglycemic drug, used as positive control), and in the groups treated with P. florida extracts. In DC group, the treatment with P. florida was found to prevent diabetes, according to histopathological studies of the kidneys, pancreas, and liver of rats. In conclusion, this study has shown that the treatment with P. florida decreased oxidative stress and glucose levels in the blood, as well as restoring changes in lipid profiles.

Therapeutic Potential of Curcumin, a Bioactive Compound of Turmeric, in Prevention of Streptozotocin-Induced Diabetes through the Modulation of Oxidative Stress and Inflammation

This study evaluates the anti-diabetic potential and underlying mechanisms of curcumin in streptozotocin (STZ)-induced type 2 diabetes mellitus (T2DM) rats. The rats were randomly divided into four groups: normal control, negative control (diabetic group), diabetic group receiving glibenclamide (positive control group), and curcumin plus STZ (treatment group). The anti-diabetic activities of curcumin were examined at a dose of 50 mg/kg body weight through physiological, biochemical, and histopathological analysis. Compared to the normal control group rats, elevated levels of glucose, creatinine, urea, triglycerides (TG), and total cholesterol (TC) and low levels of insulin were found in the negative control rats. Curcumin treatment showed a significant decrease in these parameters and an increase in insulin level as compared to negative control rats. In negative control rats, a reduced level of antioxidant enzymes and an increased level of lipid peroxidation and inflammatory marker levels were noticed. Oral administration of curcumin significantly ameliorated such changes. From histopathological findings, it was noted that diabetic rats showed changes in the kidney tissue architecture, including the infiltration of inflammatory cells, congestion, and fibrosis, while oral administration of curcumin significantly reduced these changes. Expression of IL-6 and TNF-α protein was high in diabetic rats as compared to the curcumin treatment groups. Hence, based on biochemical and histopathological findings, this study delivers a scientific suggestion that curcumin could be a suitable remedy in the management of diabetes mellitus.

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.

Himalayan Sources of Anthocyanins and Its Multifunctional Applications: A Review

Anthocyanins, the colored water-soluble pigments, have increasingly drawn the attention of researchers for their novel applications. The sources of anthocyanin are highly diverse, and it can be easily extracted. The unique biodiversity of the Himalayan Mountain range is an excellent source of anthocyanin, but it is not completely explored. Numerous attempts have been made to study the phytochemical aspects of different Himalayan plants. The distinct flora of the Himalayas can serve as a potential source of anthocyanins for the food industry. In this context, this review is an overview of the phytochemical studies conducted on Himalayan plants for the estimation of anthocyanins. For that, many articles have been studied to conclude that plants (such as Berberis asiatica, Morus alba, Ficus palmata, Begonia xanthina, Begonia palmata, Fragaria nubicola, etc.) contain significant amounts of anthocyanin. The application of Himalayan anthocyanin in nutraceuticals, food colorants, and intelligent packaging films have also been briefly debated. This review creates a path for further research on Himalayan plants as a potential source of anthocyanins and their sustainable utilization in the food systems.

Health-Promoting compounds in Potatoes: Tuber exhibiting great potential for human health

Potatoes are consumed worldwide because of their high accessibility, low cost, taste, and diversity of cooking methods. The high carbohydrate content of potatoes masks the presence of -vitamins, polyphenols, minerals, amino acids, lectins and protein inhibitors in the minds of consumers. The consumption of potatoes faces challenges among health-conscious people. This review paper attempted to provide up-to-date information on new metabolites reported in potatoes that play role in disease prevention and overall human well-being. We tried to compile information on antidiabetic, antihypertensive, anticancer, antiobesity, antihyperlipidemic, and anti-inflammatory potential of potato along with role in improving gut health and satiety. In-vitro studies, human cell culture, and experimental animal and human clinical studies showed potatoes to exhibit a variety of health-enhancing properties. This article will not only popularize potato as a healthy food, but will also improve its use as a staple for the foreseeable future.

Phytochemical component and toxicological evaluation of purple sweet potato leaf extract in male Sprague–Dawley rats

This study assessed the toxicity of lutein-rich purple sweet potato leaf (PSPL) extract in male Sprague–Dawley rats.

Methods and study design: A total of 54 adult male Sprague–Dawley rats were used. For the acute toxicity study, three rats in the acute control group were fed 2,000 mg/kg of PSPL for 14 days. The subacute toxicity study included six rats each in four groups administered 50, 250, 500, or 1,000 mg/kg for 28 days and observed for further 14 days without treatment in the subacute control and subacute satellite groups. Changes in body weight; blood biochemistry; hematological parameters; relative organ weight; and histological sections of the heart, kidney, liver, pancreas, aorta, and retina were observed for signs of toxicity.

Results: The gradual increase in weekly body weight, normal level full blood count, normal liver and kidney profile, relative organ weight, and histological sections of all stained organ tissue in the treated group compared with the acute, subacute, and satellite control groups demonstrated the absence of signs of toxicity.

Conclusion: Lutein-rich PSPL extract shows no signs of toxicity up to 2,000 mg/kg/day.

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.

Quercetin, a Plant Flavonol Attenuates Diabetic Complications, Renal Tissue Damage, Renal Oxidative Stress and Inflammation in Streptozotocin-Induced Diabetic Rats

Diabetes mellitus is a metabolic syndrome characterized by increased glucose levels, oxidative stress, hyperlipidemia, and frequently decreased insulin levels. The current research was carried out for eight consecutive weeks to evaluate the possible reno-protective effects of quercetin (50 mg/kg b.w.) on streptozotocin (STZ) (55 mg/kg b.w.) induced diabetes rat models. Various physiological, biochemical, and histopathological parameters were determined in control, diabetic control, and quercetin-treated diabetic rats. The current findings demonstrated that diabetes control rats showed significantly decreased body weights (198 ± 10 vs. 214 ± 13 g) and insulin levels (0.28 ± 0.04 vs. 1.15 ± 0.05 ng/mL) in comparison to normal control. Besides this, the other parameters showed increased values, such as fasting blood glucose, triglyceride (TG), and total cholesterol levels (99 ± 5 vs. 230 ± 7 mg/dL, 122.9 ± 8.7 vs. 230.7 ± 7.2 mg/dL, 97.34 ± 5.7 vs. 146.3 ± 8 mg/dL) (p < 0.05). In addition, the urea and creatinine levels (39.9 ± 1.8 mg/dL and 102.7 ± 7.8 μmol/L) were also high in diabetes control rats. After 8 weeks of quercetin treatment in STZ-treated animals, body weight, insulin, and fasting blood sugar levels were significantly restored (p < 0.05). The inflammatory markers (TNF-α, IL-6, and IL-1β) were significantly increased (52.64 ± 2, 95.64 ± 3, 23.3 ± 1.2 pg/mL) and antioxidant enzymes levels (SOD, GST, CAT, and GSH) were significantly decreased (40.3 ± 3 U/mg, 81.9 ± 10 mU/mg, 14.2 ± 2 U/mg, 19.9 ± 2 μmol/g) in diabetic rats. All the parameters in diabetic animals treated with quercetin were restored towards their normal values. Histopathological findings revealed that the quercetin-treated group showed kidney architecture maintenance, reduction of fibrosis, and decreased expression of COX-2 protein. These results determined that quercetin has reno-protective effects, and conclude that quercetin possesses a strong antidiabetic potential and might act as a therapeutic agent in the prevention or delay of diabetes-associated kidney dysfunction.

Stress induced production of plant secondary metabolites in vegetables: Functional approach for designing next generation super foods

Plant secondary metabolites are vital for human health leading to the gain the access to natural products. The quality of crops is the result of the interaction of different biotic and abiotic factors. Abiotic stresses during plant growth may reduce the crop performance and quality of the produce. However, abiotic stresses can result in numerous physiological, biochemical, and molecular responses in plants, aiming to deal with these conditions. Abiotic stresses are also elicitors of the biosynthesis of plant secondary metabolites in plants which possess plant defense mechanisms as well as human health benefits such as anti-inflammatory, antioxidative properties etc. Plants either synthesize new compounds or alter the concentration of bioactive compounds. Due to increasing attention towards the production of bioactive compounds, the understanding of crop responses to abiotic stresses in relation to the biosynthesis of bioactive compounds is critical. Plants alter their metabolism at the genetic level in response to different abiotic stresses resulting the changes in secondary metabolite production. Transcriptional factors regulate genes responsible for secondary metabolite biosynthesis in several plants under stress conditions. Understanding the signaling pathways involved in the secondary metabolite biosynthesis has become easy with the use of molecular biology. Therefore, aim of writing the review is to focus on secondary metabolite production in vegetable crops, their health benefits and transcription regulation under various abiotic stresses.

Unveiling Natural and Semisynthetic Acylated Flavonoids: Chemistry and Biological Actions in the Context of Molecular Docking

Acylated flavonoids are widely distributed natural metabolites in medicinal plants and foods with several health attributes. A large diversity of chemical structures of acylated flavonoids with interesting biological effects was reported from several plant species. Of these, 123 compounds with potential antimicrobial, antiparasitic, anti-inflammatory, anti-nociceptive, analgesic, and anti-complementary effects were selected from several databases including SCI-Finder, Scopus, Google Scholar, Science Direct, PubMed, and others. Some selected reported biologically active flavonoids were docked in the active binding sites of some natural enzymes, namely acetylcholinesterase, butyrylcholinesterase, α-amylase, α-glucosidase, aldose reductase, and HIV integrase, in an attempt to underline the key interactions that might be responsible for their biological activities.

The Effect of Polyphenol Extract from Rosa Roxburghii Fruit on Plasma Metabolome and Gut Microbiota in Type 2 Diabetic Mice

Rosa roxburghii fruit is an underutilized functional food abundant in polyphenols. Polyphenols have been proved to have antidiabetic effects. This study investigates the effects of Rosa roxburghii fruit polyphenols extract (RPE) on plasma metabolites and gut microbiota composition in streptozotocin (STZ)- and high-fat diet- induced type 2 diabetes using metabolomics and 16S rRNA gene sequencing. The induced diabetic mice were fed with 400 mg/kg body weight RPE for 8 weeks. RPE demonstrated hypoglycemic, hypolipidemic, and anti-inflammatory effects. Colonic oxidative stress biomarkers were also lowered by RPE. Besides, RPE decreased plasma ceramides and tyrosine levels and increased carnitine and phosphatidylinositols levels, indicating improved insulin resistance, lipid metabolism, and immune response. Furthermore, RPE decreased abundances of Lachnospiraceae and Rikenellaceae and increased abundances of Erysipelotrichaceae and Faecalibaculum. Metabolic function prediction of the gut microbiota by PICRUSt demonstrated that RPE downregulated the phosphotransferase system. Taken together, these findings demonstrated that RPE has the potential to prevent type 2 diabetes by regulating the plasma metabolites and gut microbes.

The Impact of Purple-Flesh Potato (Solanum tuberosum L.) cv. "Shadow Queen" on Minor Health Complaints in Healthy Adults: A Randomized, Double-Blind, Placebo-Controlled Study

The purple-flesh potato (Solanum tuberosum L.) cultivar "Shadow Queen" (SQ) naturally contains anthocyanins. This randomized, double-blind, placebo-controlled study determines whether ingesting purple potatoes increases the number of mesenchymal stem cells (MSC) and improves stress response, a minor health complaint in healthy adults (registration number: UMIN000038876). A total of 15 healthy subjects (ages: 50-70 years) with minor health complaints were randomly assigned to one of two groups. For 8 weeks, the placebo group received placebo potatoes cv. "Haruka" and the test group received test potato cv. SQ containing 45 mg anthocyanin. The MSC count and several stress responses were analyzed at weeks 0 and 8 of the intake periods. The ingestion of a SQ potato did not affect the MSC count but markedly improved psychological stress response, irritability, and depression as minor health complaints compared with "Haruka". No adverse effects were noted. Hence, an 8-week intake of SQ could improve stress responses.

β-Sitosterol Glucoside-Loaded Nanosystem Ameliorates Insulin Resistance and Oxidative Stress in Streptozotocin-Induced Diabetic Rats

β-Sitosterol glucoside (SG), isolated from Senecio petasitis (Family Asteraceae), was loaded in self-nanoemulsifying drug delivery systems (SEDDS) in a trial to enhance its solubility and biological effect. Various co-surfactants were tested to prepare a successful SEDDS. The selected SG-loaded SEDDS had a droplet size of 134 ± 15.2 nm with a homogenous distribution (polydispersity index 0.296 ± 0.02). It also demonstrated a significant augmentation of SG in vitro release by 4-fold compared to the free drug suspension. The in vivo insulin sensitivity and antidiabetic effect of the prepared SG-loaded SEDDS were further assessed in streptozotocin-induced hyperglycemic rats. The hypoglycemic effect of SG-loaded nanosystem was evidenced by decreased serum glucose and insulin by 63.22% and 53.11%, respectively. Homeostasis model assessment-insulin resistance (HOMA-IR) index demonstrated a significant reduction by 5.4-fold in the diabetic group treated by SG-loaded nanosystem and exhibited reduced glucagon level by 40.85%. In addition, treatment with SG-loaded nanosystem significantly decreased serum MDA (malondialdehyde) and increased catalase levels by 38.31% and 64.45%, respectively. Histopathological investigations also supported the protective effect of SG-loaded nanosystem on the pancreas. The promising ability of SG-loaded nanosystem to ameliorate insulin resistance, protect against oxidative stress, and restore pancreatic β-cell secretory function warrants its inclusion in further studies during diabetes progression.

Phytochemical Analysis, α-Glucosidase and α-Amylase Inhibitory Activities and Acute Toxicity Studies of Extracts from Pomegranate (Punica granatum) Bark, a Valuable Agro-Industrial By-Product

Punica granatum is a tree of the Punicaceae family which is widespread all over the world with several types of varieties. Its fruit juice is highly prized, whereas the bark, rich in in phytochemicals such as flavonoids, hydrolysable tannins, phenolic acids, and fatty acids, is regarded an agro-industrial waste. It is utilized in traditional medicine for its medicinal properties in the treatment and prevention of a variety of ailments. This study aims to extract and to separate the phytochemical compounds from the bark of P. granatum, to identify them and to study the inhibitory effect of its extracts against antidiabetic activity. First, we carried out successive hot extractions with solvents (chloroform, acetone, methanol, and water) of increasing polarity by the Soxhlet. Then, using both qualitative and quantitative phytochemical investigation, we were able to identify groups of chemicals that were present in all extracts. We identified the majority of the molecular structures of chemicals found in each extract using HPLC-DAD analysis. The inhibition against both intestinal α-glucosidase and pancreatic α-amylase enzymes by P. granatum extracts was used to evaluate their potential antidiabetic effect in vitro. Our results demonstrated the great potential of the acetone extract. Ellagic acid, (−)-catechin, vanillin and vanillic acid were proposed as the most active compounds by the correlation analysis, and their actions were confirmed through the calculation of their IC₅₀ and the determination of their inhibition mechanisms by molecular modelling. To summarize, these results showed that P. granatum bark, a natural agro-industrial by-product, may constitute a promising option for antidiabetic therapeutic therapy.

Momordica charantia nanoparticles potentiate insulin release and modulate antioxidant gene expression in pancreas of diabetic rats

Background

Green synthesis of nanoparticles with medicinal plants has inherent potential in the management of diabetes mellitus. This study synthesized Momordica charantia nanoparticles using silver nitrate to investigate the antidiabetic properties of this extract and the synthesized nanoparticles in vivo.

Results

The M. charantia nanoparticles used were synthesized biologically under ambient conditions from methanolic leaf extract of M. charantia using 1 mM concentration of aqueous silver nitrate and characterized using spectroscopic methods, FTIR and scanning electron microscopy. In vivo, the antidiabetic activity of M. charantia nanoparticle was assessed in streptozotocin-induced (65 mg/kg) rats. Rats were treated with M. charantia nanoparticle (50 mg/kg), aqueous leaf extract (100 mg/kg) metformin (100 mg/kg) and silver nitrate nanoparticle (10 mg/kg) for 21 days. Following treatment, rats were killed for biochemical analysis. Also, reverse transcript-polymerase chain reaction analyses of Takeda-G-protein-receptor-5, glucagon-like peptide-1, Insulin, superoxide dismutase, catalase and Nuclear factor-erythroid factor 2-related factor 2 (NRF2) - were carried out in the pancreas. A significant reduction in blood sugar levels was noted in rats treated with M. charantia nanoparticles. A reduction (p < 0.05) of pancreas alanine transaminase, aspartate aminotransferase and alkaline phosphatase was observed when compared with diabetic untreated rats. M. charantia nanoparticles significantly increase the antioxidant enzymes in diabetic rats when compared with diabetic untreated rats. The decrease in the level of triglyceride, cholesterol and low-density lipoprotein was observed when compared with diabetic control rats and also a significant increase in the expression of Takeda-G-protein-receptor-5, glucagon-like peptide-1, insulin, superoxide dismutase, catalase and NFE2-related factor 2 genes was observed when compared with diabetic untreated rats.

Conclusions

Momordica charantia nanoparticles exhibited potential antidiabetic activity in the rat model of diabetes and thus may serve as a therapeutic agent that could be developed for medical applications in the future.

The relationship between glycosylated hemoglobin level and red blood cell storage lesion in blood donors

BACKGROUND

Glycosylated hemoglobin (HbA1c), not routinely screened in blood donors, is associated with morphological, biochemical, and functional abnormalities of red blood cells (RBCs) and with enhanced oxidative stress. We aimed to explore HbA1c levels in blood donors and their effect on RBC storage.

STUDY DESIGN AND METHODS

An analytical cross-sectional study was conducted on 875 eligible blood donors aged 18-60 years from May 1, 2021, to August 30, 2021. Two selected groups of donors (HbA1c <6.5%, n = 10; HbA1c ≥ 6.5%, n = 10) exhibiting as similar as possible baseline values (such as age, sex, and living habits, etc.) were recruited for blood donation in leukoreduced CPDA-1 units. RBC morphological, biochemical, structural, and oxidative stress states were measured during 5-35 days of storage.

RESULTS

Elevated HbA1c prevalence was 37%, including 31.7% (277/875) in the prediabetes range (HbA1c 5.7%-6.4%) and 5.4% (47/875) in the diabetes range (HbA1c ≥ 6.5%). Age, body mass index (BMI), smoking, and alcohol consumption were the main factors influencing the HbA1c levels. During storage, high-HbA1c group had abnormal RBC morphology, impaired membrane function, and ion imbalance (higher mean corpuscular volume, distribution width, hemolysis rate, potassium ion efflux, and phosphatidylserine exposure) as compared with low HbA1c group. Additionally, RBC oxidative stress was significantly increased in donors with high HbA1c levels during 21-35 days.

DISCUSSION

Blood donors proportion with abnormal HbA1c levels was relatively high, and donor HbA1c levels may be associated with stored RBCs capacity. Our study provides new insights into the different effects of donor HbA1c levels on RBC storage lesions.

Fustin ameliorates hyperglycemia in streptozotocin induced type-2 diabetes via modulating glutathione/Superoxide dismutase/Catalase expressions, suppress lipid peroxidation and regulates histopathological changes

Streptozotocin (STZ) 60 mg/kg, i.p.-induced diabetes in rat’s results into hyperglycemia, impaired oxidative stress, lipid profile, insulin levels and changes in body weight. Treatment with antihyperglycemics and antioxidants are accounted to produce favorable effect in this paradigm. Fustin, a flavonoid derived from Rhus verniciflua, extract of Rhus verniciflua reported to exhibit anti-hyperglycemic, antioxidant, anti-microbial, anti-arthritic effects, anti-obesity effects, antiplatelet effects and anti-cancer effects. However, no evidence is existing on effect of fustin on STZ-induction diabetes. Thus, we evaluated its effects against diabetes in STZ-induced rodents. Blood glucose, Insulin, lipid peroxidation (MDA), superoxide dismutase (SOD), catalase activity (CAT), glutathione (GSH) and lipid profile levels was assessed. After 30 days diabetes induction rodents showed a severe increased blood sugar level, MDA, high density lipid and decreased cholestrol, triglyceride, GSH, SOD, CAT, respectively.

Oppositely, treatment with fustin (50–100 mg/kg/p.o., two times daily, 30 days) enhanced blood glucose, lipid profile levels Insulin. Meanwhile, reduced MDA and enhanced GSH, SOD, and CAT in diabetic rats. Glibenclamide 5 mg/kg/p.o. also enhanced diabetes-induced complications and decreased oxidative stress. Further histopathology of pancreas confirms the protective effect fustin in STZ-induction diabetes in animals. In conclusion, the study revealed treatments with fustin avoid the changes in body weight, blood glucose, lipid profile and oxidative stress. As a results of these finding may lead to the growth of a choice of medicine for hyperglycemic in the future.

Fustin Ameliorates Elevated Levels of Leptin, Adiponectin, Serum TNF-α, and Intracellular Oxidative Free Radicals in High-Fat Diet and Streptozotocin-Induced Diabetic Rats

Fustin is a prominent ingredient of Rhus verniciflua Stokes (Anacardiaceae) and has a wide range of pharmacological and clinical effects. The present study attempted to evaluate the antidiabetic potential of fustin in streptozotocin- and high-fat diet-induced diabetes in rats. The efficacy of fustin 50 mg/kg and 100 mg/kg/day p.o. was studied in 60% of total calories from fat as a high-fat diet along with single-dose administration streptozotocin (50 mg/kg, i.p.) experimentally induced diabetes in rats for 42 days. The mean body weight; blood glucose; and biochemical parameters such as lipid profile, total protein (TP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), insulin, leptin levels, adiponectin levels, glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) activity in serum were measured. The rats' weight was maintained in the fustin groups compared to the diabetic control group. Diabetes caused a significant increase in serum levels in blood glucose, lipid profile, MDA, TNF-α, ALT, and AST parameters and a decrease in serum insulin, adiponectin, leptin, GSH, SOD, and CAT compared to healthy rats. The treatment regimen with fustin (50 and 100 mg/kg) significantly restored all serum parameters in test groups. The present study found clinical evidence for the first time regarding the significant antidiabetic property of fustin, which could be a worthwhile candidate for the treatment of diabetes.

Acylated anthocyanins: A review on their bioavailability and effects on postprandial carbohydrate metabolism and inflammation

Anthocyanins, the natural red and purple colorants of berries, fruits, vegetables, and tubers, improve carbohydrate metabolism and decrease the risk factors of metabolic disorders, but their industrial use is limited by their chemical instability. Acylation of the glycosyl moieties of anthocyanins, however, changes the chemical properties of anthocyanins and provides enhanced stability. Thus, acylated anthocyanins are more usable as natural colorants and bioactive components of innovative functional foods. Acylated anthocyanins are common in pigmented vegetables and tubers, the consumption of which has the potential to increase the intake of health-promoting anthocyanins as part of the daily diet. For the first time, this review presents the current findings on bioavailability, absorption, metabolism, and health effects of acylated anthocyanins with comparison to more extensively investigated nonacylated anthocyanins. The structural differences between nonacylated and acylated anthocyanins lead to enhanced color stability, altered absorption, bioavailability, in vivo stability, and colonic degradation. The impact of phenolic metabolites and their potential health effects regardless of the low bioavailability of the parent anthocyanins as such is discussed. Here, purple-fleshed potatoes are presented as a globally available, eco-friendly model food rich in acylated anthocyanins, which further highlights the industrial possibilities and nutritional relevance of acylated anthocyanins. This work supports the academic community and industry in food research and development by reviewing the current literature and highlighting gaps of knowledge.

A Novel Ultrasound-Assisted Extraction Method for the Analysis of Anthocyanins in Potatoes (Solanum tuberosum L.)

Purple potato is one of the least known and consumed potato varieties. It is as rich in nutrients, amino acids and starches as the rest of the potato varieties, but it also exhibits a high content of anthocyanins, which confer it with some attractive health-related properties, such as antioxidant, pain-relieving, anti-inflammatory and other promising properties regarding the treatment of certain diseases. A novel methodology based on ultrasound-assisted extraction has been optimized to achieve greater yields of anthocyanins. Optimal extraction values have been established at 70 °C using 20 mL of a 60% MeOH:H₂O solution, with a pH of 2.90 and a 0.5 s⁻¹ cycle length at 70% of the maximum amplitude for 15 min. The repeatability and intermediate precision of the extraction method have been proven by its relative standard deviation (RSD) below 5%. The method has been tested on Vitelotte, Double Fun, Highland and Violet Queen potatoes and has demonstrated its suitability for the extraction and quantification of the anthocyanins found in these potato varieties, which exhibit notable content differences. Finally, the antioxidant capacity of these potato varieties has been determined by means of 2,2-diphenyl-1-picrylhydrazyl (DDPH) radical scavenging and the values obtained were similar to those previously reported in the literature.

Effect of Cooking Methods on Bioactivity of Polyphenols in Purple Potatoes

Purple-fleshed potato (Solanum tuberosum L.) is a good dietary source of anthocyanins, flavonols, and polyphenolic acids, mostly chlorogenic acid. The objective of this study was to examine the impacts of cooking methods including boiling, steaming, and the newly developed vacuum-sealed boiling (VSBoil) on extractability and bioactivity of polyphenolic compounds in a purple potato (PP) cultivar, Purple Pelisse. Data showed that boiling and steaming reduced the total polyphenolic content in PP. High-performance liquid chromatography analysis showed that steaming slightly reduced the extractable chlorogenic acid content, while VSBoil increased it. For DPPH free radical scavenging activities, VSBoil and steaming effectively preserved the antioxidant activity of a polyphenol-rich extract of PP, while boiling resulted in a significant reduction compared to raw potato extract. All extracts effectively suppressed bursts of intracellular reactive oxygen species in human colonic epithelial cells upon hydrogen peroxide induction, of which the extract from the VSBoil group showed the highest antioxidant potential. In addition, all extracts showed anti-inflammatory effects in Caco-2 cells induced with tumor necrosis factor-α. In conclusion, the content and bioactivity of extractable polyphenols were largely retained in PP subjected to different cooking processes. VSBoil resulted in the highest content of extractable polyphenolic compounds and bioactivity among tested cooking methods.

Antitumor and antioxidant activities of purple potato ethanolic extract and its interaction with liposomes, albumin and plasmid DNA

The aim of the study was to broadly determine the biological activities of purple potato ethanolic extract of the Blue Congo variety (BCE). The antioxidant activity of BCE was determined in relation to liposome membranes, and peroxidation was induced by UVB and AAPH. To clarify the antioxidant activity of BCE, we investigated its interactions with hydrophilic and hydrophobic regions of a membrane using fluorimetric and FTIR methods. Next, we investigated the cytotoxicity and pro-apoptotic activities of BCE in two human colon cancer cell lines (HT-29 and Caco-2) and in normal cells (IPEC-J2). In addition, the ability to inhibit enzymes that are involved in pro-inflammatory reactions was examined. Furthermore, BCE interactions with serum albumin and plasmid DNA were investigated using steady state fluorescence spectroscopy and a single molecule fluorescence technique (TCSPC-FCS). We proved that BCE effectively protects lipid membranes against the process of peroxidation and successfully inhibits the cyclooxygenase and lipoxygenase enzymes. Furthermore, it interacts with the hydrophilic and hydrophobic parts of lipid membranes as well as with albumin and plasmid DNA. It was observed that BCE is more cytotoxic against colon cancer cell lines than normal IPEC-J2 cells; it also induces apoptosis in cancer cell lines, but does not induce cell death in normal cells.

Effect of Standard and High-Fat Diets during Modeling of Streptozotocin-Induced Diabetes in Rats on the Development of Complications

For evaluation of the effect of high-fat diet on the development of diabetic complications, the rats were maintained on standard or high-fat diet. In 3 weeks, diabetes mellitus was modeled by single intraperitoneal injection of streptozotocin. Changes in hematological parameters, physical and biochemical parameters of the urine, and in the development of thermal allodynia were different after 15-week standard and high-fat diets.

Loganic Acid, an Iridoid Glycoside Extracted from Cornus mas L. Fruits, Reduces of Carbonyl/Oxidative Stress Biomarkers in Plasma and Restores Antioxidant Balance in Leukocytes of Rats with Streptozotocin-Induced Diabetes Mellitus

The various complications related to diabetes are due to the alteration in plasma components and functional activity of blood cells, hence the search for preventive remedies that would ameliorate the clinical condition of patients is a relevant problem today. The main aim of the present study was to examine the antidiabetic potency and antioxidant effects of loganic acid (LA) in blood of diabetic rats. LA showed a restoration of balance between functioning of antioxidant defense system and oxidative stress in leukocytes without notable effects on blood glucose levels when administered orally to rats (20 mg/kg b.w./day) for 14 days. LA ameliorated antioxidant status in leukocytes, as indicated by increasing the content of reduced glutathione and activities of catalase, glutathione peroxidase and glutathione reductase along with decreasing levels of intracellular reactive oxygen species. In addition, we observed the ability of LA to protect against formation and accumulation of glycation and oxidation protein products and malondialdehyde derivates in plasma. Therefore, LA showed antioxidant properties that may have beneficial effects under diabetes. Such results may represent LA as one of the plant components in the development of new drugs that will correct metabolic and functional disorders in leukocytes under diabetes.

Analysis of Total Phenols, Sugars, and Mineral Elements in Colored Tubers of Solanum tuberosum L

The use of colored tubers of Solanum tuberosum L. is growing worldwide due to their health benefits and attractive color. The positive health effects of purple-fleshed tubers are a result of anthocyanins and various phenolic compounds. The aim of this study was to evaluate and compare variety Blue Congo and its cross-breeds of Desiree and Granola to yellow-fleshed tubers. The concentration of total phenols, anthocyanins, sugars, and mineral elements were evaluated in all tubers. The results showed differences between all tested materials, with largest differences in sugar content. Moreover, the results confirmed the preservation of health improving compounds of Blue Congo when cross-bred with yellow-fleshed tubers. The total phenolic content and anthocyanin concentrations of all analyzed tubers were above the comparison yellow ones.

Anthocyanin Pigments: Beyond Aesthetics

Anthocyanins are polyphenol compounds that render various hues of pink, red, purple, and blue in flowers, vegetables, and fruits. Anthocyanins also play significant roles in plant propagation, ecophysiology, and plant defense mechanisms. Structurally, anthocyanins are anthocyanidins modified by sugars and acyl acids. Anthocyanin colors are susceptible to pH, light, temperatures, and metal ions. The stability of anthocyanins is controlled by various factors, including inter and intramolecular complexations. Chromatographic and spectrometric methods have been extensively used for the extraction, isolation, and identification of anthocyanins. Anthocyanins play a major role in the pharmaceutical; nutraceutical; and food coloring, flavoring, and preserving industries. Research in these areas has not satisfied the urge for natural and sustainable colors and supplemental products. The lability of anthocyanins under various formulated conditions is the primary reason for this delay. New gene editing technologies to modify anthocyanin structures in vivo and the structural modification of anthocyanin via semi-synthetic methods offer new opportunities in this area. This review focusses on the biogenetics of anthocyanins; their colors, structural modifications, and stability; their various applications in human health and welfare; and advances in the field.

Cyclophilin A (CyPA) as a Novel Biomarker for Early Detection of Diabetic Nephropathy in an Animal Model

BACKGROUND AND AIM

Type 2 diabetes mellitus (DM) is the most common single cause of the end-stage renal disease (ESRD). Cyclophilin A (CyPA) is an 18-kD protein. The connection between diabetic nephropathy (DN) and the secreted form of CyPA (sCyPA) has been elucidated in this study that aims to investigate sCyPA correlation with renal dysfunction.

MATERIALS AND METHODS

Thirty-four male adult Wistar rats weighing 180-220 g were used. Animals were divided into a study group and a control group, 17 rats in each. Streptozotocin (STZ) and nicotine amide were used to damage some pancreatic cells for induction of type 2 DM. Comparison was made between the study and the control groups. Moreover, a comparison was made between the members of the study group before and after induction of DN.

RESULTS

The rat model that exhibited a higher concentration of urinary sCyPA was detected early in the eighth week. There was a significantly higher level of 24-h urinary CyPA in the study group compared to the control group (p-value=0.004) and there was a significant elevation in the 24-h urinary Cyp-A in the study group after injection of STZ compared to the values before injection (p-value <0.001). Immunohistochemical analysis of renal tissue revealed that the mean expression of CyPA was higher in the study group than in the control group. For the urinary 24-h CYP-A, using a cutoff of 1.15 ng/mL, the accuracy was 72.4%, sensitivity was (77.8%) and specificity was (67%).

CONCLUSION

According to this animal study, we proved that CyPA is a valuable marker for DN. It is a more sensitive, noninvasive and rapid biomarker for early detection of any renal affection in human diabetic patients.

Targets and mechanisms of dietary anthocyanins to combat hyperglycemia and hyperuricemia: a comprehensive review

Hyperglycemia and hyperuricemia are both metabolic disorders related to excessive amount of metabolites in blood, which are considered as high risk factors for the development of many chronic diseases. Enzymes, cells, tissues and organs, which are relevant to metabolism and excretion of glucose and UA, are usually regarded to be the targets in treatment of hyperglycemia and hyperuricemia. Several drugs have been commonly applied to combat hyperglycemia and hyperuricemia through various targets but with unignorable side effects. Anthocyanins have become promising alternatives against hyperglycemia and hyperuricemia because of their bio-activities with little side effects. Structurally different anthocyanins from berry fruits, cherries and purple sweet potato lead to the diverse functional activity and property. This review is aimed to illustrate the specific targets that are available for anthocyanins from berry fruits, cherries and purple sweet potato in hyperglycemia and hyperuricemia management, as well as discuss the structure-activity relationship, and the underlying mechanisms associated with intracellular signaling pathway, anti-oxidative stress and anti-inflammation. In addition, the relationship of hyperglycemia and hyperuricemia, and the possibly regulative role of anthocyanins against them, along with the effects of anthocyanins in clinical trial are mentioned.

Coumarin-chalcone hybrids targeting insulin receptor: Design, synthesis, anti-diabetic activity, and molecular docking

Four series of thirteen new coumarin-chalcone hybrids (DPCU 1-13, DPCT 1-13, DCCU 1-13 and DCCT 1-13) were designed and synthesized using Biginelli synthesis, Pechmann condensation, Acetylation, and Claisen-Schmidt reactions. Synthesized compounds were tested for insulin receptor in silico docking studies (PDB ID: 1IR3); DCCU 13 and DCCT 13 derivatives received the lowest docking score; Streptozocin (STZ) and Nicotinamide (NA) induced type II diabetes was tested for their anti-diabetic activity in rats. In vivo tests suggested that fasting blood glucose levels of animals treated with DCCU 13 (30 mg/kg body weight) and DCCT 13 (30 mg/kg body weight) were significantly and moderately suppressed, respectively, relative to fasting blood glucose levels of diabetic control animals. Similarly, therapy with DCCU 13 and DCCT 13 attenuated oxidative stress parameters such as lipid peroxidation (MDA), superoxide dismutase (SOD) and increased the glutathione (GSH) in the liver and pancreas in a dose-dependent manner. In comparison, therapy with DCCU 13 (30 mg/kg body weight) mitigated alterations in the histological architecture of the liver and pancreatic tissue. These results indicated that the hybrids DUUC 13 and DCCT 13 at 30 mg/kg had an anti-hyperglycemic and antioxidant impact on STZ + NA mediated type II diabetes in rats. Further detailed work could be required to determine the precise mode of action of the anti-diabetic behavior of hybrids.

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.

Dunaliella salina Attenuates Diabetic Neuropathy Induced by STZ in Rats: Involvement of Thioredoxin

Diabetic neuropathy (DN) is a widespread disabling disorder including peripheral nerves' damage. The aim of the current study was to estimate the potential ameliorative effect of Dunaliella salina (D. salina) on DN and the involvement of the thioredoxin. Diabetes was induced by streptozotocin (STZ; 50 mg/kg; i.p). Glimepiride (0.5 mg/kg) or D. salina powder (100 or 200 mg/kg) were given orally, after 2 days of STZ injection for 4 weeks. Glucose, total antioxidant capacity (TAC), superoxide dismutase (SOD), and catalase (CAT) serum levels as well as brain contents of thioredoxin (Trx), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) were measured with the histopathological study. STZ-induced DN resulted in a significant (P < 0.05) rise in glucose blood level and brain contents of TNF-α and IL-6 and produced a reduction in serum TAC, SOD, CAT, and brain Trx levels with irregular islets of Langerhans cells and loss of brain Purkinje cells. Treatment with glimepiride or both doses of D. salina alleviated these biochemical and histological parameters as compared to the STZ group. D. salina has a neurotherapeutic effect against DN via its inhibitory effect on inflammatory mediators and oxidative stress molecules with its upregulation of Trx activity.

Antioxidative and Hypoglycemic Effect of Ta-ermi Extracts on Streptozotocin-Induced Diabetes

INTRODUCTION

The purpose of the present study was to reveal the potential positive effect of the Ta-ermi extracts on oxidative stress and streptozotocin (STZ)-diabetic mice and rats treated with Ta-ermi water- and alcohol-extracts.

METHODS

The study was carried out using three experimental model: 1) in vitro experiments whereby Ta-ermi extracts were incubated with free radical generators such as 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) to evaluate Ta-ermi's antioxidant effects; 2) testing the hypoglycemic effects of Ta-ermi extracts in streptozotocin (STZ)-induced diabetic mice; and 3) testing the beneficial effects of Ta-ermi extracts on mitochondrial complex I function using STZ-diabetic rats.

RESULTS

In vitro antioxidant experiments showed that both of the extracts could scavenge free radicals and exhibited inhibitory effects on glucosidase and aldose reductase with differential effects between water extract and alcohol extract. In the STZ mouse diabetic model, both the water- and alcohol-extracts attenuated body weight decrease, decreased blood glucose levels in a concentration-dependent manner, improved insulin sensitivity, and increased oral glucose tolerance ability. In the STZ-diabetic rat model, both the water- and alcohol-extracts were found to be able to lower blood glucose levels in the diabetic animals with no effects on body weight changes. Moreover, in the STZ-diabetic rats, both the water- and alcohol-extracts of Ta-ermi could inhibit the increase of mitochondrial NADH/ubiquinone oxidoreductase (complex I) activity in the pancreas and enhanced complex I activity in the liver but showed no effect on lung or kidney mitochondrial complex I.

DISCUSSION

The present study points to the potential medicinal value of Ta-ermi's water and alcohol extracts in lowering blood glucose and decreasing diabetic oxidative stress. One limitation of our study is that the compound or compounds that actually have this beneficial effect in the extracts remain unknown at this time. Therefore, the future studies should be focused on the identification of the components in the extracts that exhibit anti-oxidative and hypoglycemic effects.

CONCLUSION

Taken together, our studies using different experimental paradigms indicate that Ta-ermi extracts possess antioxidant and anti-diabetic properties and may be employed as functional food ingredients for the remission of diabetes.