The effects of traditional antidiabetic plants on in vitro glucose diffusion

Phytochemical analysis, identification of bioactive compounds using GC-MS, in vitro and in silico hypoglycemic potential, in vitro antioxidant potential, and in silico ADME analysis of Chlorophytum comosum root and leaf

Chlorophytum comosum is a plant with medicinal potential traditionally used to treat different diseases. The present study aimed to determine the bioactive compounds, hypoglycemic and antioxidant potential of C. comosum root and leaf. The ethyl acetate extracts of C. comosum root and leaf were analyzed by GC-MS to determine the bioactive compounds. The hypoglycemic potential of the extracts was evaluated by α-amylase, α-glucosidase, glucose diffusion inhibitory assays, and glucose adsorption assay. The ethyl acetate extract of C. comosum root inhibited α-amylase, α-glucosidase, and glucose diffusion in a concentration-dependent manner with IC50 values of 205.39 ± 0.15, 179.34 ± 0.3 and 535.248 μg/mL, respectively, and the leaf extract inhibited α-amylase and α-glucosidase enzymes with IC50 values of 547.99 ± 0.09, and 198.18 ± 0.25 μg/mL respectively. C. comosum root and leaf extracts also improved glucose adsorption. Heptadecanoic acid and dodecanoic acid were identified as potential compounds with hypoglycemic properties through molecular docking. The extracts were also assessed for their antioxidant activity using DPPH, ABTS, and FRAP assays. C. comosum root and leaf extracts were also able to scavenge DPPH radicals with IC50 values of 108.37 ± 0.06 and 181.79 ± 0.09 µM and ABTS radicals with IC50 values of 126.24 ± 0.13 and 264.409 ± 0.08 µM, respectively. The root and leaf extracts also reduced the ferricyanide complex to ferrocyanide with higher reducing powers of 2.24 ± 0.02 and 1.65 ± 0.03, respectively. The results showed that the ethyl acetate extract of C. comosum root has significant antioxidant and hypoglycemic potential compared to the leaf extract. Thus, it can also be studied to isolate the potential compounds with antihyperglycemic activities.

Design, synthesis, α-amylase and glucose diffusion inhibition, and molecular docking studies of new indenopyrazolones bearing benzothiazole derivatives

An eco-friendly facile synthesis of a series of twenty 1-(4/6-substitutedbenzo[d]thiazol-2-yl)-3-(phenyl/substitutedphenyl)indeno[1,2-c]pyrazol-4(1H)-ones 7a-t was achieved by the reaction of 2-(benzoyl/substitutedbenzoyl)-(1H)-indene-1,3(2H)-dione 3a-t and 2-hydrazinyl-4/6-substitutedbenzo[d]thiazole 6a-t in presence of freshly dried ethanol and glacial acetic acid under reflux conditions in good yields. The newly synthesized derivatives were well characterized using different physical and spectral techniques (FTIR, 1H NMR & 13C NMR, and HRMS). All the compounds were subjected to assess their in vitro α-amylase and glucose diffusion inhibitory activity. Amongst them, the compounds 7i and 7l showed better α-amylase inhibitory activity demonstrating IC50 values of 92.99±1.94 µg/mL and 95.41±3.92 µg/mL, respectively in comparison to the standard drug acarbose (IC50 value of 103.60±2.15 µg/mL). The derivatives 7d and 7k exhibited good glucose diffusion inhibition with values of 2.25±1.16 µg/mL and 2.63±1.45 µg/mL, respectively with standard reference acarbose (2.76±0.55 µg/mL). The observed α-amylase inhibitory activity findings were corroborated through molecular docking investigations, particularly for the highly active compounds 7i (binding energy -8.0 kcal/mol) and 7l (binding energy -8.2 kcal/mol) respectively, in comparison to acarbose with a value of binding energy -6.9 kcal/mol for α-amylase.

Phytochemical Profiling and Assessment of Antidiabetic Activity of Curcuma Angustifolia Rhizome Methanolic Extract: An In Vitro and In Silico Analysis

Curcuma angustifolia Roxb. is a plant with medicinal potential, traditionally used to treat different diseases. The present study aimed to determine the antidiabetic activity of C. angustifolia rhizome in vitro and in silico. The methanolic extract of C. angustifolia rhizome was analyzed by FTIR and GC-MS to determine the phytochemicals present. The antidiabetic potential of the extract was evaluated by different assays in vitro. The extract inhibited both α-amylase and α-glucosidase enzymes and the glucose diffusion through the dialysis membrane in a concentration-dependent manner with IC50 values of 530.39±0.09, 293.75±0.11, and 551.74±0.3 μg/ml respectively. The methanolic extract also improved yeast cell's ability to take up glucose across plasma membranes and the adsorption of glucose. The findings were supported by molecular docking studies. The results showed that the methanol extract of C. angustifolia rhizome has significant antidiabetic activity and thus can be also studied to isolate the potential compound with antidiabetic activities.

Chinese bayberry (Myrica rubra Sieb. et Zucc.) leaves proanthocyanidins inhibit intestinal glucose transport in human Caco-2 cells

Background: The hypoglycemic effects of Chinese bayberry leaves proanthocyanidins (BLPs) have been demonstrated. It is unclear, nevertheless, whether BLPs reduced postprandial blood glucose levels by regulating glucose uptake and glucose transport. Method: This study investigated the effect of BLPs (25, 50, and 100 μg/mL) on glucose uptake and glucose transport in human intestinal epithelial cells (Caco-2 cells). The uptake of 2-Deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl) amino]-D-glucose (2-NBDG) and disaccharidases activity in Caco-2 cells were measured. The glucose transport ability across the cell membrane was determined using the established Caco-2 monolayer model. The transcript and protein levels of key glucose transporters were analyzed using real-time quantitative polymerase chain reaction (RT-qPCR) and western blotting, respectively. Results: The results showed that BLPs significantly decreased glucose uptake and disaccharidases activity (p < 0.05). Otherwise, BLPs treatment obviously inhibited glucose transport across the Caco-2 monolayer in both simulated-fast (5 mM glucose) and simulated-fed (25 mM glucose) conditions. It was attributed to the suppression of glucose transporter2 (GLUT2) and sodium-dependent glucose cotransporter 1 (SGLT1) by BLPs. BLPs were found to significantly downregulated the transcript level and protein expression of glucose transporters (p < 0.05). Meanwhile, the mRNA expression of phospholipase C (PLC) and protein kinase C (PKC) involved in the signaling pathway associated with glucose transport were decreased by BLPs. Conclusion: These results suggested that BLPs inhibited intestinal glucose transport via inhibiting the expression of glucose transporters. It indicated that BLPs could be potentially used as a functional food in the diet to modulate postprandial hyperglycemia.

In-silico, in-vitro and in-vivo Biological Activities of Flavonoids for the Management of Type 2 Diabetes

In spite of the fact that many medicinal plants have been truly utilized for the management of diabetes all through the world, very few of them have been reported scientifically. Recently, a diverse variety of animal models have been established to better understand the pathophysiology of diabetes mellitus, and new medications to treat the condition have been introduced in the market. Flavonoids are naturally occurring substances that can be found in plants and various foods and may have health benefits in the treatment of neuropathic pain. Flavonoids have also been shown to have an anti-inflammatory impact that is significant to neuropathic pain, as indicated by a decrease in several pro-inflammatory mediators such TNF-, NF-B IL-6, and IL-1. Flavonoids appear to be a viable novel therapy option for macrovasular complications in preclinical models; however, human clinical data is still inadequate. Recently, several in silico, in-vitro and in-vivo aproaches were made to evaluate mechanisms associated with the pathogenesis of diabetes in a better way. Screening of natural antidiabetic agents from plant sources can be analysed by utilizing advanced in-vitro techniques and animal models. Natural compounds, mostly derived from plants, have been studied in diabetes models generated by chemical agents in the majority of research. The aim of this work was to review the available in silico, in-vitro and animal models of diabetes for screening of natural antidiabetic agents. This review contributes to the scientist's design of new methodologies for the development of novel therapeutic agents having potential antihyperglycemic activity.

Dose-dependent anti-hyperglycemic & anti-dyslipidemic potential of aqueous leaves extract of Typha elephantina in-vivo and in-vitro

Diabetes mellitus is among the fundamental causes of illness and millions of deaths around the globe are directly attributed to it each year. Current antidiabetic medications often lack sustained glycemic control and carry significant risks of side effects. As a result, the use of plant-based treatments has gained popularity. In this experimental study, we evaluated the aqueous extracts (LQE) of Typha elephantina (also known as Elephant grass) leaves collected from freshwater marshes, for their potential anti-hyperglycemic and anti-hyperlipidemic antioxidant effects in healthy streptozotocin caused diabetic-mice. We employed glucose adsorption tests at different glucose levels and glucose diffusion tests to assess the in-vitro antidiabetic action of plant extract. For the in-vivo trail, we measured fasting blood glucose (FBG), glucose tolerance (GTT), as well as long-term anti-diabetic, anti-hyperlipidemic, and antioxidant activities. Our results from the glucose diffusion test indicated that the extract was highly effective at both low glucose concentrations (5 mmol L) and high glucose concentrations (100 mmol L). However, the glucose-diffusion ability reached its peaked at an excessively high dosage of the aqueous extract, suggesting a dose-related effect. Similarly, we observed that high doses of TEL.AQ extracts (400 mg/kg body weight) significantly reduced blood glucose levels in healthy mice during the glucose tolerance test (GTT) at 3 h and fasting blood glucose studies (FBG) at 6 h. Furthermore, the high-dose TEL.AQ extract effectively reduced liver-related serum markers and blood-glucose concentration (BGC) in severely chronic diabetic rats. The extract dosage also influenced lipid profile, conjugate and unconjugated bilirubin levels, cholesterol, triglycerides, HDL, and total bilirubin levels. Additionally, after administering a high extract dose, we observed considerable improvement in the liver homogenate markers CAT, POD, and SOD. In contrast, the extract at a low dosage (100 mg/kg), showed minimal, while a moderate dose (200 mg/kg), yielded promising results.

Exploring antidiabetic potential of a polyherbal formulation Madhurakshak Activ: An in vitro and in silico study

Madhurakshak Activ (MA), a commercial polyherbal antidiabetic preparation is known to manage diabetes mellitus (DM) by reducing blood glucose levels. However, lacks systematic mechanistic evaluation for their molecular and cellular mode of actions. In the present study, hydro-alcoholic and aqueous extract of MA were evaluated for their effects on glucose adsorption, diffusion, amylolysis kinetics and transport across the yeast cells using in vitro techniques. Bioactive compounds identified from MA by LC-MS/MS were assessed for their binding potential against DPP-IV and PPARγ via an in silico approach. Our results revealed that the adsorption of glucose increased dose dependently (5 mM -100 mM). Both extracts exhibited linear glucose uptake into the yeast cells (5 mM - 25 mM), whereas glucose diffusion was directly proportional to time (30-180 min). Pharmacokinetic analysis revealed drug-like properties and low toxicity levels for all the selected compounds. Among the tested compounds, 6-hydroxyluteolin (-8.9 against DPP-IV and PPARγ) and glycyrrhetaldehyde (DPP-IV -9.7 and PPARγ -8.5) have exhibited higher binding affinity compared to the positive control. Therefore, the above compounds were further considered for molecular dynamics simulation which showed stability of the docked complexes. Hence, studied mode of actions might produce a concerted role of MA in increasing the rate of glucose absorption and uptake followed by the in silico studies which suggest that the compounds identified from MA may inhibit DPP-IV and PPARγ phosphorylation.

In Vitro Antidiabetic, Antioxidant, and Prebiotic Activities of the Chemical Compounds Isolated from Guizotia abyssinica

India and Ethiopia employ Guizotia abyssinica (niger plant) as a source of edible vegetable oil. Previous studies have documented the niger plant's antioxidant properties and dietary benefits. Here, G. abyssinica extract was obtained and ten known bioactive components (1-10) were isolated. The antioxidant, antidiabetic, and prebiotic properties of whole extract and isolated components of niger and the plant's ability to cooperate symbiotically with probiotic strains were examined. Compound 10, myricetin-3-O-L-rhamnoside, had the highest antioxidant capacity measured in the 2,2-diphenylpicrylhydrazyl (DPPH, 4629.76 ± 6.02 µmol Trolox equivalent/g compound) and ferric-reducing antioxidant power (FRAP, 2667.62 ± 7.5 mol Trolox equivalent/g compound) assays. The lowest α-amylase and glycogen phosphorylase activities and glucose diffusion were obtained with whole G. abyssinica extracts, whereas compounds 8-10 had moderate inhibitory effects. G. abyssinica extract also induced the highest glucose absorption by yeast cells in the presence of 5 mM of glucose. Moreover, Lactobacillus plantarum and L. rhamnosus incubated with β-sitosterol 3-O-D-glucoside (compound 7) showed the highest prebiotic activity score. The levels of L-(+)-lactic acid isomer in the probiotic strains were the highest in presence of the whole extract and decreased progressively in the presence of flavonoid glycosides (compounds 8-10) and β-sitosterol 3-O-D-glucoside. The enzymatic profile of the probiotic strains was unaffected by the niger extract and compounds 7-10. The findings revealed that the biological activities of G. abyssinica extract are mediated by the compounds 1-10, and it may be considered as a promising plant for the treatment of diabetes mellitus.

Antidiabetic Actions of Ethanol Extract of Camellia sinensis Leaf Ameliorates Insulin Secretion, Inhibits the DPP-IV Enzyme, Improves Glucose Tolerance, and Increases Active GLP-1 (7-36) Levels in High-Fat-Diet-Fed Rats

Camellia sinensis (green tea) is used in traditional medicine to treat a wide range of ailments. In the present study, the insulin-releasing and glucose-lowering effects of the ethanol extract of Camellia sinensis (EECS), along with molecular mechanism/s of action, were investigated in vitro and in vivo. The insulin secretion was measured using clonal pancreatic BRIN BD11 β cells, and mouse islets. In vitro models examined the additional glucose-lowering properties of EECS, and 3T3L1 adipocytes were used to assess glucose uptake and insulin action. Non-toxic doses of EECS increased insulin secretion in a concentration-dependent manner, and this regulatory effect was similar to that of glucagon-like peptide 1 (GLP-1). The insulin release was further enhanced when combined with isobutylmethylxanthine (IBMX), tolbutamide or 30 mM KCl, but was decreased in the presence of verapamil, diazoxide and Ca²⁺ chelation. EECS also depolarized the β-cell membrane and elevated intracellular Ca²⁺, suggesting the involvement of a K_ATP-dependent pathway. Furthermore, EECS increased glucose uptake and insulin action in 3T3-L1 cells and inhibited dipeptidyl peptidase IV (DPP-IV) enzyme activity, starch digestion and protein glycation in vitro. Oral administration of EECS improved glucose tolerance and plasma insulin as well as inhibited plasma DPP-IV and increased active GLP-1 (7-36) levels in high-fat-diet-fed rats. Flavonoids and other phytochemicals present in EECS could be responsible for these effects. Further research on the mechanism of action of EECS compounds could lead to the development of cost-effective treatments for type 2 diabetes.

Dissection of Genetic Effects, Heterosis, and Inbreeding Depression for Phytochemical Traits in Coriander

Increasing seed yield, fatty acids, and essential oil content are the main objectives in breeding coriander. However, in order to achieve this, there is a need to understand the nature of gene action and quantify the heterosis and inbreeding depression. Towards this, six genetically diverse parents, their 15 F₁ one-way hybrids, and 15 F₂ populations were evaluated under different water treatments. The genetic effects of general (GCA) and specific combining ability (SCA) and their interactions with water treatment were significant for five traits. Water deficit stress decreased all traits in both F₁ and F₂ generations except for the essential oil content, which was significantly increased due to water deficit stress. Under water deficit stress, a non-additive gene action was predominant in the F₁ generation, while an additive gene action was predominant in the F₂ generation for all the traits except seed yield under severe water deficit stress. There was a positive high heterosis for the traits examined in some hybrids. Furthermore, in the F₂ generation, even after inbreeding depression, some promising populations displayed appropriate mean performance. The results show that the parents used for crossing had a rich, diverse gene pool for the traits studied. Therefore, selection between the individuals of relevant F₂ populations could be used to develop high yielding hybrids or superior lines.

Polyphenol-Rich Leaf of Annona squamosa Stimulates Insulin Release from BRIN-BD11 Cells and Isolated Mouse Islets, Reduces (CH2O)n Digestion and Absorption, and Improves Glucose Tolerance and GLP-1 (7-36) Levels in High-Fat-Fed Rats

Annona squamosa, commonly known as custard apple, is traditionally used for the treatment of various diseases including diabetes, cardiovascular disease (CVD), and gastritis. This study was undertaken to investigate the effects of an ethanolic (80% v/v) extract of A. squamosa (EEAS) leaves in vitro on insulin secretion from clonal pancreatic BRIN BD11 β-cells and mouse islets, including mechanistic studies on the effect of EEAS on membrane potential and intracellular calcium ion concentration. Additional in vitro glucose-lowering actions were assessed. For in vivo studies, high-fat-fed (HFF) obese/normal rats were selected. EEAS increased insulin secretion in vitro in a dose-dependent manner. This effect was linked to β-cell membrane depolarisation and cytoplasmic Ca²⁺ influx. In the presence of isobutyl methylxanthine (IBMX), tolbutamide, or KCl, the insulin-releasing effect of EEAS was increased, suggesting its effect was also mediated via a K_ATP-independent pathways. EEAS inhibited insulin glycation, glucose absorption, and DPP-IV enzyme activity in vitro and enhanced glucose uptake and insulin action in 3T3L1 cells. In vivo, gut motility, food intake, glucose tolerance, plasma insulin, and active GLP-1 (7-36) levels were improved, whereas plasma DPP-IV levels were reduced in HFF rats. EEAS attenuated the absorption of sucrose and glucose as well as decreased serum glucose levels after sucrose loading and in situ intestinal perfusion in non-diabetic rats. Rutin, proanthocyanidin, and squafosacin G were putatively identified as the anti-hyperglycaemic phytomolecules in EEAS using HPLC followed by LC-MS analysis. This study illustrates the potential of A. squamosa and its phytoconstituents as a source of potential antidiabetic agents.

Agrimonia eupatoria L.: An integrative perspective on ethnomedicinal use, phenolic composition and pharmacological activity

ETHNOPHARMACOLOGICAL RELEVANCE

Agrimonia eupatoria L., a plant which belongs to the Rosaceae family, is widespread in temperate regions, particularly throughout the northern hemisphere. In folk medicine, this plant species has been used for its astringent, anti-inflammatory, analgesic and hypotensive properties as well as in gastrointestinal disorders. As these biological properties have been linked to its phenolic composition, this plant species could be an interesting source of bioactive compounds with therapeutic potential.

AIM OF THE STUDY

The aim of the present review is to provide a comprehensive overview of the scientific literature on A. eupatoria, particularly in regard to its ethnobotanics and ethnomedicinal uses, phenolic composition and biological and pharmacological activities.

MATERIAL AND METHODS

Literature was retrieved from several bibliographic sources, namely PubMed, ScienceDirect and Google Scholar, since the first report on A. eupatoria in 1993.

RESULTS

Regarding the phytochemical composition, A. eupatoria is rich in phenolic acids, flavonoids and tannins. The most commonly reported compounds are astragalin, cynaroside, hyperoside, isoquercitrin, isovitexin, rutin, catechin, procyanidin B3 and agrimoniin. In terms of bioactivity, extracts or fractions obtained from this plant species have shown antioxidant, antimicrobial, antidiabetic, antinociceptive and anti-inflammatory properties, among others. So far, two clinical studies with the infusion of A. eupatoria have shown hepatoprotective properties as well as a protective role in cardiovascular disease, metabolic disorders and diabetes.

CONCLUSIONS

In this review, an integrative perspective on ethnomedicinal use, phenolic composition and pharmacological activity of A. eupatoria has been provided. As can be seen, this plant species exhibits several potential applications, including those beyond its traditional ethnomedicinal uses, as the safety of its consumption has been shown clinically. There still is limited pharmacological evidence that corroborates the ethnomedicinal uses of this plant species as well as regarding the specific bioactive compounds.

Insulin Secretory Actions of Ethanol Extract of Eucalyptus citriodora Leaf, including Plasma DPP-IV and GLP-1 Levels in High-Fat-Fed Rats, as Well as Characterization of Biologically Effective Phytoconstituents

Due to the numerous adverse effects of synthetic drugs, researchers are currently studying traditional medicinal plants to find alternatives for diabetes treatment. Eucalyptus citriodora is known to be used as a remedy for various illnesses, including diabetes. This study aimed to explore the effects of ethanol extract of Eucalyptus citriodora (EEEC) on in vitro and in vivo systems, including the mechanism/s of action. The methodology used involved the measurement of insulin secretion from clonal pancreatic β-cells, BRIN BD11, and mouse islets. Other in vitro systems further examined EEEC’s glucose-lowering properties. Obese rats fed a high-fat-fed diet (HFF) were selected for in vivo evaluation, and phytoconstituents were detected via RP-HPLC followed by LC-MS. EEEC induced insulin secretion in a concentration-dependent manner with modulatory effects, similar to 1 µM glucagon-like peptide 1 (GLP-1), which were partly declined in the presence of Ca^2+-channel blocker (Verapamil), K_ATP-channel opener (Diazoxide), and Ca²⁺ chelation. The insulin secretory effects of EEEC were augmented by isobutyl methylxanthine (IBMX), which persisted in the context of tolbutamide or a depolarizing concentration of KCl. EEEC enhanced insulin action in 3T3-L1 cells and reduced glucose absorption, and protein glycation in vitro. In HFF rats, it improved glucose tolerance and plasma insulin, attenuated plasma DPP-IV, and induced active GLP-1 (7-36) levels in circulation. Rhodomyrtosone B, Quercetin-3-O-β-D-glucopyranoside, rhodomyrtosone E, and quercitroside were identified as possible phytoconstituents that may be responsible for EEEC effects. Thus, these findings revealed that E. citriodora could be used as an adjunct nutritional supplement to manage type 2 diabetes.

Analysis of the phytochemicals of Coriandrum sativum and Cichorium intybus aqueous extracts and their biological effects on broiler chickens

Spices and herbs can be used as feed additives and viable alternatives to antibiotics in chicken production. This study analyzed the phytochemicals, minerals, and antioxidant activity of aqueous extracts from Coriandrum sativum seeds and Cichorium intybus roots. The effects of different concentrations of C. sativum and C. intybus extracts on blood parameters, growth and carcass traits, biochemical parameters, and antioxidant activity of broiler chicks were also examined. The results showed that C. sativum aqueous extract has relatively higher contents of total flavonoids and total phenolic acids than C. intybus aqueous extract. Both extracts contain elevated mineral elements, especially iron, potassium, and sodium. Therefore, dietary supplementation of C. sativum seed and C. intybus root extracts could enhance broiler chicken growth performance, carcass characteristics, liver function, lipid profile, and antioxidant status. These extracts could be utilized as natural feed additives and growth promoters for broiler chickens.

Investigation of healing effects of lemon (Citrus limonum) seeds lyophilized extracts on experimental diabetic rats

In this study, the effects of lemon seed lyophilised extract (LSLE) were investigated on the diabetic rats. Groups were conducted as normal control (NC), diabetic control (DC), diabetic + 20 mg acarbose/kg bw (DAC)), diabetic + 100 mg LSLE/kg bw (DLSLE1), diabetic + 200 LSLE mg/kg bw (DLSLE2) and diabetic + 400 LSLE mg/kg bw (DLSLE4). The protective and antioxsidant effects of LSLE on experimental diabetes complications were evaluated by measuring hepatic and renal damage biomarkers (HRDBs), antioxidant defence system constituents (ADSCs), diabetes biomarkers and MDA content in tissues of diabetic rats. Glucose, HRDBs, HbA1c, lipid profile (LP) levels increased in DC compared to NC whereas these parameters of the supplementation groups showed a significant decreas compared to DC. Also, it was determined an increase MDA content and fluctuate ADSCs in the DC tissues whereas the LSLE restored the parameters towards to the NC. It can be said that LSLE is may have healings effects against diabetic complications.

Zimbro (Juniperus communis L.) as a Promising Source of Bioactive Compounds and Biomedical Activities: A Review on Recent Trends

Plant-derived products and their extracted compounds have been used in folk medicine since early times. Zimbro or common juniper (Juniperus communis) is traditionally used to treat renal suppression, acute and chronic cystitis, bladder catarrh, albuminuria, leucorrhea, and amenorrhea. These uses are mainly attributed to its bioactive composition, which is very rich in phenolics, terpenoids, organic acids, alkaloids, and volatile compounds. In the last few years, several studies have analyzed the huge potential of this evergreen shrub, describing a wide range of activities with relevance in different biomedical discipline areas, namely antimicrobial potential against human pathogens and foodborne microorganisms, notorious antioxidant and anti-inflammatory activities, antidiabetic, antihypercholesterolemic and antihyperlipidemic effects, and neuroprotective action, as well as antiproliferative ability against cancer cells and the ability to activate inductive hepato-, renal- and gastroprotective mechanisms. Owing to these promising activities, extracts and bioactive compounds of juniper could be useful for the development of new pharmacological applications in the treatment of several acute and chronic human diseases.

Ethnobotanical and phytochemical aspects of the edible herb Coriandrum sativum L

Coriandrum sativum (coriander) is an edible herb in the family Apiaceae. The leaves, fruits, and stems of C. sativum have long been used as culinary spice due to their favorable odor. Traditional practitioners used this plant for treating different diseases like blepharitis, scabies, aphthous stomatitis, laryngitis, headache, and palpitation. In modern researches, coriander has demonstrated anxiolytic, anticonvulsant, antimigraine, neuroprotective, analgesic, diuretic, hypoglycemic, hypolipidemic, hypotensive, anticancer, and antioxidant activities. Coriander contains a wide range of bioactive phytochemicals among which phenylpropenes, terpenoids, isocoumarins, phytosterols, and fatty acids are the most important. This review provides information about the botanical and ethnobotanical aspects, chemical profile, therapeutic uses in Islamic traditional medicine (ITM), and recent pharmacological studies of coriander effects. The results have shown that coriander and its monoterpenoid compound, linalool, can be considered as potential drug candidates for treating metabolic syndrome and different inflammatory conditions especially neural and CNS diseases.

Insulin secretory and antidiabetic actions of Heritiera fomes bark together with isolation of active phytomolecules

In folklore, Heritiera fomes (H. fomes) has been extensively used in treatment of various ailments such as diabetes, cardiac and hepatic disorders. The present study aimed to elucidate the antidiabetic actions of hot water extract of H. fomes (HWHF), including effects on insulin release from BRIN BD11 cells and isolated mouse islets as well as glucose homeostasis in high-fat-fed rats. Molecular mechanisms underlying anti-diabetic activity along with isolation of active compounds were also evaluated. Non-toxic concentrations of HWHF stimulated concentration-dependent insulin release from isolated mouse islets and clonal pancreatic β-cells. The stimulatory effect was potentiated by glucose and isobutyl methylxanthine (IBMX), persisted in presence of tolbutamide or a depolarizing concentration of KCl but was attenuated by established inhibitors of insulin release such as diazoxide, verapamil, and Ca2+ chelation. HWHF caused depolarization of the β-cell membrane and increased intracellular Ca2+. The extract also enhanced glucose uptake and insulin action in 3T3-L1 differentiated adipocytes cells and significantly inhibited in a dose-dependent manner starch digestion, protein glycation, DPP-IV enzyme activity, and glucose diffusion in vitro. Oral administration of HWHF (250 mg/5ml/kg b.w.) to high-fat fed rats significantly improved glucose tolerance and plasma insulin responses and it inhibited plasma DPP-IV activity. HWHF also decreased in vivo glucose absorption and intestinal disaccharidase activity while increasing gastrointestinal motility and unabsorbed sucrose transit. Compounds were isolated from HWHF with similar molecular weights to quercitrin (C21 H20 O11) ranging from 447.9 to 449.9 Da which stimulated the insulin release in vitro and improved both glucose tolerance and plasma insulin responses in mice. In conclusion, H. fomes and its water-soluble phytochemicals such as quercitrin may exert antidiabetic actions mediated through a variety of mechanisms which might be useful as dietary adjunct in the management of type 2 diabetes.

In vitro and in vivo antihyperglycemic activity of the ethanol extract of Heritiera fomes bark and characterization of pharmacologically active phytomolecules

OBJECTIVE

This study aimed to demonstrate the mechanistic basis of Heritiera fomes, which has traditionally been used to treat diabetes.

METHODS

Clonal pancreatic β-cells and primary islets were used to measure insulin release. 3T3-L1 cells were used to analyse insulin action, and in vitro systems were used to measure further glucose-lowering activity. In vivo assessment was performed on streptozotocin (STZ)-induced type-2 diabetic rats and reversed-phase-HPLC followed by liquid chromatography mass spectrometry (LC-MS) to detect bioactive molecules.

KEY FINDINGS

Ethanol extract of Heritiera fomes (EEHF) significantly increased insulin release with stimulatory effects comparable to 1 µM glucagon-like peptide 1, which were somewhat reduced by diazoxide, verapamil and calcium-free conditions. Insulin release was stimulated by tolbutamide, isobutyl methylxanthine and KCl. EEHF induced membrane depolarization and increased intracellular Ca2+ levels. EEHF enhanced glucose uptake in 3T3L1 cells and decreased protein glycation. EEHF significantly inhibited postprandial hyperglycaemia following sucrose loading and inversely elevated unabsorbed sucrose concentration in the gut. It suppressed glucose absorption during in situ gut perfusion. Furthermore, EEHF improved glucose tolerance, plasma insulin and gut motility, and decreased plasma dipeptidyl peptidase IV activity. Procyanidins, epicatechin and proanthocyanidins were some of the identified bioactive constituents that may involve in β-cell actions.

CONCLUSIONS

This study provides some evidence to support the use of H. fomes as an antidiabetic traditional remedy.

Use of Complementary and Alternative Medicine Among Patients With Epilepsy and Diabetes Mellitus, Focusing on the Outcome of Treatment

Introduction: Millions all over the world live with epilepsy, and they may require long-term drug treatment. The use and interest in complementary and alternative medicine (CAM) have grown over the previous years. Coadministration of herbal products with medicines may result in adverse drug reactions (ADRs) and/or unfavorable interactions. The aims of this study were to determine the prevalence of CAM use among patients with epilepsy, to compare the results to those of the patients with diabetes mellitus (DM), to reveal factors that may drive the use of CAM, and to measure outcomes and adherence. It was also our intent to have state-of-the-art information on CAM use in our region among patients with the two diseases above.

Materials and Methods: We conducted a non-interventional study using a self-developed questionnaire. It was distributed among adult patients with either epilepsy or DM who also suffered from cardiovascular consequences. A database was compiled from the anonymous questionnaires filled in voluntarily by the patients. Basic statistics were used to analyze this database.

Results: A total of 227 questionnaires were filled in by 127 patients (55.9%) with epilepsy and 100 patients (44.1%) with DM. Mean age was 54.54 ± 17.33 years. Of the patients, 50.2% were male. Average body weight was 80.3 ± 17.3 kg. Of the patients, 22 (9.7%) used CAM because they believed in CAM. Two of them reported ADRs. Among the patients with epilepsy, the ratio was only 7.9% compared to 12% among those with DM. While the number of CAM users was higher among younger patients with epilepsy, it was the elderly patients with DM who tended to use CAM.

Conclusion: Attention should be paid to reliance on CAM during the follow-up. Our finding that health-conscious patients tend to use CAM more often (than the general population) may indicate it is necessary to discuss CAM usage sincerely. CAMs modulating cytochrome P450 (CYP) enzymes were the most common, leading to interactions with medication used and resulting in ADRs. This shows the importance of educating patients and treating team including clinical pharmacists in this field.

Aloe vera carbohydrates regulate glucose metabolism through improved glycogen synthesis and downregulation of hepatic gluconeogenesis in diabetic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Aloe vera (L.) Burm.f. is an ancient medicinal plant that belongs to the family Asphodelaceae. It has a rich source of bioactive constituents such as carbohydrates, polyphenols, peptides, sterols and tannins, etc. Aloe vera has multiple biological activities such as anti-inflammatory, antioxidant and antidiabetic activity etc. AIM OF THE STUDY: The present study investigated the antidiabetic mechanism of Aloe vera carbohydrate fraction (AVCF) and aimed to provide insights into the regulation of carbohydrate metabolism enzymes in glucose homeostasis.

MATERIALS AND METHODS

The antidiabetic effect of AVCF was evaluated using α-amylase, α-glucosidase inhibition, glucose diffusion and glucose uptake assay. The in vitro AVCF effect on insulin secretion, cell proliferation and inflammatory markers were determined using streptozotocin-induced oxidative stress on RIN-m5F cells. Streptozotocin-induced male Wistar diabetic rats were treated for 21 days with AVCF (54 mg/kg bw). The in vivo AVCF effect was measured on fasting plasma glucose, insulin, glucagon, hexokinase, glycogen synthase and glucose-6-phosphatase, levels in diabetic rats. Histopathological studies for organ-specific effects in the pancreas, liver and small intestine were also conducted.

RESULTS

AVCF-treated RIN-m5F cells significantly increased BrdU levels, with insulin secretion, and decreased TNF-α, IL-6 and nitric oxide levels. AVCF treated streptozotocin-induced diabetic rats showed significantly decreased fasting plasma glucose, glucagon and glucose-6-phosphatase levels with a concomitant increase in insulin, hexokinase, and glycogen synthase levels and, glycogen content. These findings corroborate with the improved hepatic glycogen content in the PAS stained histological section of the liver of AVCF treated diabetic rats.

CONCLUSION

These results suggest that CF of Aloe vera improved glucose metabolism by activation of glycogenesis and down-regulation of gluconeogenesis thereby, maintaining glucose homeostasis. Hence, AVCF can be used as an alternative medicine in the alleviation of diabetes mellitus symptoms.

In Vitro Antioxidant Properties, Glucose-Diffusion Effects, α-Amylase Inhibitory Activity, and Antidiabetogenic Effects of C. Europaea Extracts in Experimental Animals

Caralluma europaea (Guss.) N.E.Br. (C. europaea), is a medicinal plant used traditionally to treat diabetes mellitus (DM) in Morocco. This study aimed to investigate the in vitro antioxidant properties, glucose diffusion effects, α-amylase inhibitory activity, and pancreatic protective effects of C. europaea in experimental alloxan-induced diabetes in mice. Total phenolic contents were determined by Folin–Ciocalteu colorimetric method, total flavonoid contents were measured by aluminum chloride colorimetric assay, and tannins contents were determined by employing the vanillin method. C. europaea ethyl acetate fraction exhibited high antioxidant potential in terms of radical scavenging (DPPH) (IC50 = 0.22 ± 0.01 mg/mL), β-carotene bleaching activity (IC50 = 1.153 ± 0.07 mg/mL), and Ferric-reducing antioxidant power. Glucose diffusion was significantly inhibited by the ethyl acetate fraction at 60,120and 180 min, while the aqueous extract did not have this inhibitory effect when compared with the control group. Potent α-amylase inhibitory activity was observed in the ethyl acetate fraction and the aqueous extract in vitro and in vivo using STZ-diabetic rats. On the other hand, the administration of the ethyl acetate fraction (60 mg/kg) significantly attenuated alloxan-induced death and hyperglycemia in treated mice. Furthermore, histopathological investigations revealed that the ethyl acetate fraction protected islets of Langerhans against alloxan-induced tissue alterations. These results suggest that C. europaea exhibited an important antihyperglycemic effect via the inhibition of glucose diffusion and pancreatic α-amylase activity. In addition, the antidiabetogenic effect of C. europaea might be attributed to their polyphenol and flavonoid compounds, which could be reacted alone, or in synergy, to scavenge the free radicals produced by the alloxan.

In vitro antidiabetic, antioxidant activities and GC-MS analysis of Rhynchostylis Retusa and Euphorbia Neriifolia leaf extracts

This study aimed to assess the antidiabetic, and antioxidant potential of Rhynchostylis retusa and Euphorbia neriifolia, well known for traditional ethnomedicinal uses in North-east India. Leaf extracts prepared in water, methanol and petroleum ether were evaluated for in vitro antidiabetic and antioxidant assay using α-amylase inhibition, glucose diffusion method and DPPH radical scavenging activity. The α-amylase inhibition with E. neriifolia methanolic extract at 400 μg/ml (66.67%) and R. retusa aqueous extract at 300 μg/ml (58.15%) were stronger than in equivalent concentrations of acarbose, i.e., 62.17, and 51.52%, respectively. Aqueous extract R. retusa showed a maximum 67.65% inhibition of glucose diffusion at 180 min in comparison to control without leaf extract. The DPPH radical scavenging activity of E. neriifolia extract in methanol was significantly better than equivalent aqueous or ether extract. However, the solvent choice had little impact on antioxidant activity in R. retusa. GC-MS analysis revealed the presence of a large number of phytochemicals in methanol fraction of E. neriifolia aqueous extracts in comparison to R. retusa. Though the in vitro α-amylase inhibition or glucose diffusion retardation implied potential medicinal use of endangered orchid R. retusa and E. neriifolia, further investigation may be warranted for identification of relevant bio-active compounds and in vivo validation of their pharmacological properties.

Identification of Multiple Pancreatic and Extra-Pancreatic Pathways Underlying the Glucose-Lowering Actions of Acacia arabica Bark in Type-2 Diabetes and Isolation of Active Phytoconstituents

Acacia arabica is used traditionally to treat a variety of ailments, including diabetes. This study elucidated the antidiabetic actions of A. arabica bark together with the isolation of bioactive molecules. Insulin secretion and signal transduction were measured using clonal β cells and mouse islets. Glucose uptake was assessed using 3T3-L1 adipocytes, and in vitro systems assessed additional glucose-lowering actions. High-fat-fed (HFF) obese rats were used for in vivo evaluation, and phytoconstituents were isolated and characterised by RP-HPLC followed by LC-MS and NMR. Hot-water extract of A. arabica (HWAA) increased insulin release from clonal β cells and mouse islets by 1.3-6.8-fold and 1.6-3.2-fold, respectively. Diazoxide, verapamil and calcium-free conditions decreased insulin-secretory activity by 30-42%. In contrast, isobutylmethylxanthine (IBMX), tolbutamide and 30 mM KCl potentiated the insulin-secretory effects. The mechanism of actions of HWAA involved membrane depolarisation and elevation of intracellular Ca2+ together with an increase in glucose uptake by 3T3-L1 adipocytes, inhibition of starch digestion, glucose diffusion, dipeptidyl peptidase-IV (DPP-IV) enzyme activity and protein glycation. Acute HWAA administration (250 mg/5 mL/kg) enhanced glucose tolerance and plasma insulin in HFF obese rats. Administration of HWAA (250 mg/5 mL/kg) for 9 days improved glucose homeostasis and β-cell functions, thereby improving glycaemic control, and circulating insulin. Isolated phytoconstituents, including quercetin and kaempferol, increased insulin secretion in vitro and improved glucose tolerance. The results indicate that HWAA has the potential to treat type 2 diabetes as a dietary supplement or as a source of antidiabetic agents, including quercetin and kaempferol.

Role of zonulin and GLP-1/DPP-IV in alleviation of diabetes mellitus by peptide/polypeptide fraction of Aloe vera in streptozotocin- induced diabetic wistar rats

ETHNO-PHARMACOLOGICAL RELEVANCE

The genus Aloe has a long history of usage in medicine. Aloe barbadensis Miller, commonly known as Aloe vera, is said to possess anti-diabetic, anti-inflammatory, anti-cancer, anti-microbial, immunomodulation, wound healing properties.

AIM OF THE STUDY

In diabetes mellitus, loss in intestinal permeability is observed with high levels of zonulin and low levels of glucagon-like peptide-1 (GLP-1) leading to hyperglycemia. The aim of the study was to understand the role of peptide/polypeptide fraction (PPF) of Aloe vera in the alleviation of diabetes through maintaining the intestinal permeability by regulating the zonulin and GLP-1 levels.

MATERIALS AND METHODS

The PPF of Aloe vera was obtained through trichloroacetic acid precipitation. The anti-diabetic potential of the PPF was tested through DPP-IV inhibition, glucose diffusion assay, and by using Rin-m5F cells. The anti-diabetic potential of the PPF was tested at a dose of 0.450 mg/kg bw in vivo using streptozotocin-induced diabetic Wistar rats. The effect of PPF on fasting plasma glucose, insulin, glucagon, Zonulin, GLP-1, DPP-IV, levels were studied in diabetic rats. The histopathological studies of the pancreas, small intestine, and liver were carried out for organ-specific effects.

RESULTS

PPF has the ability to reduce fasting plasma glucose levels with concomitant increase in insulin levels in streptozotocin-induced diabetic rats. It was also observed that increase in GLP-1 levels with a decrease in DPP-IV and zonulin levels thereby mitigating the loss of intestinal permeability. These findings correlate with the small intestine's histopathological observation where the excessive proliferation of epithelium in the small intestine of diabetic rats was reduced after PPF treatment.

CONCLUSION

These results suggest that the PPF of Aloe vera alleviates diabetes through islet cell rejuvenation via GLP-1/DPP-IV pathway and thereby suggesting the usage of PPF as an alternate medicine for diabetes mellitus with the possibility to reduce the intestinal permeability and zonulin levels.

Hypoglycemic and antioxidant effects of green tomato (Physalis ixocarpa Brot.) calyxes' extracts

The aim of this study was to evaluate the hypoglycemic and antioxidant potential of green tomato (Physalis ixocarpa Brot.) calyxes' extracts. Three methods were used to obtain the extracts: maceration (M), ultrasound-assisted (US), and infusion. Regarding in vitro hypoglycemic evaluation, glucose diffusion assay and enzymatic inhibitory action of α-amylase and α-glucosidase were performed. Whereas, for in vivo assessment an oral starch tolerance test (OSTT) was tested with aqueous extracts [infusion (40 mg/kg b. wt.), maceration (M) water (98 mg/kg b. wt.), and US water (82.24 mg/kg b. wt.)] on male Wistar rats. Additionally, in vitro antioxidant activity of P. ixocarpa calyxes' was evaluated through inhibition of scavenging radical assay and lipid peroxidation. Extracts decreased the glucose diffusion in a range of 18%-56% compared with the negative control. Additionally, extracts inhibited α-amylase (above 80%) and α-glucosidase enzymes (above 90%). All groups treated with P. ixocarpa calyxes' significantly reduced the glucose levels at 120 min (infusion = 13.3%, M Water = 12.7%, and US Water = 19.4%) in comparison with the negative control, and similar levels to acarbose at 120 min (13.1%). Finally, extracts showed IC₅₀ values in a range of 2.5-6.6 µg/µl for radical scavenging, and 118-199 µg/µl for lipid oxidation. Our results show that P. ixocarpa calyxes' extracts induce hypoglycemia and antioxidant effects in vitro and in vivo. PRACTICAL APPLICATIONS: The green tomato is usually consumed in Mexico, the United States, and Central America. This fruit grows inside a calyx, which is considered an agro-food waste. However, some regions of Latin America have a traditional medicine purpose for diabetes affections. To the best of our knowledge, there are no published data that supports its hypoglycemic action. The information provided will be useful to nutraceutical applications that allow value-added products and sustainable green tomato production.

Extract of Unifloral Camellia sinensis L. Pollen Collected by Apis mellifera L. Honeybees Exerted Inhibitory Effects on Glucose Uptake and Transport by Interacting with Glucose Transporters in Human Intestinal Cells

Bee pollen possesses potential hypoglycemic effects but its inhibitory mechanisms on glucose absorption and transportation in intestinal cells still need to be clarified. Here, we determined the inhibitory effects of bee pollen extract originating from Camellia sinensis L. (BP-Cs) as well as its representative phenolic compounds on glucose uptake and transport through a human intestinal Caco-2 cell monolayer model. It showed that three representative phenolic compounds, including gallic acid (GA), 3-O-[6'-O-(trans-p-coumaroyl)-β-d-glucopyranosyl]kaempferol (K1), and 3-O-[2',6'-di-O-(trans-p-coumaroyl)-β-d-glucopyranosyl]kaempferol (K2), with contents of 27.7 ± 0.86, 9.88 ± 0.54, and 7.83 ± 0.46 μg/mg in BP-Cs extract, respectively, exerted mutual antagonistic actions interacting with glucose transporters to inhibit glucose uptake and transport based on their combination index (CI) and molecular docking analysis. K1, K2, and GA might compete with d-glucose to form hydrogen bonds with the same active residues including GLU-412, GLY-416, GLN-314, and TRP-420 in GLUT2. These findings provide us a deep understanding of the mechanisms underlying the anti-hyperglycemia by bee pollen, which provide a new sight on dietary intervention strategies against diabetes.

Effects of 22 traditional anti-diabetic medicinal plants on DPP-IV enzyme activity and glucose homeostasis in high-fat fed obese diabetic rats

The present study investigated the effects of hot water extracts of 22 medicinal plants used traditionally to treat diabetes on Dipeptidyl peptidase-IV (DPP-IV) activity both in vitro and in vivo in high-fat fed (HFF) obese-diabetic rats. Fluorometric assay was employed to determine the DPP-IV activity. For in vivo studies, HFF obese-diabetic rats were fasted for 6 h and blood was sampled at different times before and after the oral administration of the glucose alone (18 mmol/kg body weight) or with either of the four most active plant extracts (250 mg/5 ml/kg, body weight) or established DPP-IV inhibitors (10 μmol/5 ml/kg). DPP-IV inhibitors: sitagliptin, vildagliptin and diprotin A, decreased enzyme activity by a maximum of 95-99% (P<0.001). Among the 22 natural anti-diabetic plants tested, AnogeissusLatifolia exhibited the most significant (P<0.001) inhibitory activity (96 ± 1%) with IC50 and IC25 values of 754 and 590 μg/ml. Maximum inhibitory effects of other extracts: Aegle marmelos, Mangifera indica, Chloropsis cochinchinensis, Trigonella foenum-graecum and Azadirachta indica were (44 ±7%; 38 ± 4%; 31±1%; 28±2%; 27±2%, respectively). A maximum of 45% inhibition was observed with >25 μM concentrations of selected phytochemicals (rutin). A.latifolia, A. marmelos, T. foenum-graecum and M. indica extracts improved glucose tolerance, insulin release, reduced DPP-IV activity and increased circulating active GLP-1 in HFF obese-diabetic rats (P<0.05-0.001). These results suggest that ingestion of selected natural anti-diabetic plants, in particular A. latifolia, A. marmelos, T. foenum-graecum and M. indica can substantially inhibit DPP-IV and improve glucose homeostasis, thereby providing a useful therapeutic approach for the treatment of T2DM.

The therapeutic effects of Agrimonia eupatoria L

Agrimonia eupatoria L. is an herb of the Rosaceae family, widely used in traditional (folk) medicine for its beneficial effects. Its water extracts (infusions and decoctions) are used in the treatment of airway and urinary system diseases, digestive tract diseases, and chronic wounds. Phytochemical analyses of Agrimonia eupatoria L. identified a variety of bioactive compounds including tannins, flavonoids, phenolic acids, triterpenoids and volatile oils possessing antioxidant, immunomodulatory and antimicrobial activities. The authors review the available literature sources examining and discussing the therapeutic and pharmacological effects of Agrimonia eupatoria L. at the molecular level in vitro and in vivo.

Anti-hyperglycaemic and insulin-releasing effects of Camellia sinensis leaves and isolation and characterisation of active compounds

Anti-diabetic actions of Camellia sinensis leaves, used traditionally for type 2 diabetes (T2DM) treatment, have been determined. Insulin release, membrane potential and intra-cellular Ca were studied using the pancreatic β-cell line, BRIN-BD11 and primary mouse pancreatic islets. Cellular glucose-uptake/insulin action by 3T3-L1 adipocytes, starch digestion, glucose diffusion, dipeptidyl peptidase-4 (DPP-IV) activity and glycation were determined together with in vivo studies assessing glucose homoeostasis in high-fat-fed (HFF) rats. Active phytoconstituents with insulinotropic activity were isolated using reversed-phase HPLC, LCMS and NMR. A hot water extract of C. sinensis increased insulin secretion in a concentration-dependent manner. Insulinotropic effects were significantly reduced by diazoxide, verapamil and under Ca-free conditions, being associated with membrane depolarisation and increased intra-cellular Ca2+. Insulin-releasing effects were observed in the presence of KCl, tolbutamide and isobutylmethylxanthine, indicating actions beyond K+ and Ca2+ channels. The extract also increased glucose uptake/insulin action in 3T3L1 adipocyte cells and inhibited protein glycation, DPP-IV enzyme activity, starch digestion and glucose diffusion. Oral administration of the extract enhanced glucose tolerance and insulin release in HFF rats. Extended treatment (250 mg/5 ml per kg orally) for 9 d led to improvements of body weight, energy intake, plasma and pancreatic insulin, and corrections of both islet size and β-cell mass. These effects were accompanied by lower glycaemia and significant reduction of plasma DPP-IV activity. Compounds isolated by HPLC/LCMS, isoquercitrin and rutin (464·2 Da and 610·3 Da), stimulated insulin release and improved glucose tolerance. These data indicate that C. sinensis leaves warrant further evaluation as an effective adjunctive therapy for T2DM and source of bioactive compounds.

Integration of in silico, in vitro and ex vivo pharmacology to decode the anti-diabetic action of Ficus benghalensis L. bark

BACKGROUND

Traditionally, Ficus benghalensis L. is used to treat metabolic disorders and is also recorded in the Ayurvedic pharmacopeia of India. The present study aimed to evaluate the anti-diabetic property of hydroalcoholic extract/fraction(s) of F. benghalensis L. bark via in silico, in vitro, and ex vivo approach.

METHODS

Enzyme inhibitory activity, glucose uptake in rat hemidiaphragm, and glucose permeability, and adsorption assays were performed using in vitro and ex vivo methods as applicable. Further, the PASS was used to identify the probable lead enzyme inhibitors. The presence of predicted enzyme inhibitors was confirmed via the LC-MS. Similarly, the docking of ligands with respective targets was performed using autodock4.0.

RESULTS

Flavonoids rich fraction possessed the highest α-amylase, and α-glucosidase inhibitory activity followed by maximum efficacy for glucose uptake in rat hemidiaphragm. Similarly, the hydroalcoholic extract showed the highest efficacy to inhibit glucose diffusion. Likewise, 3,4-dihydroxybenzoic acid was predicted for the highest pharmacological activity for α-amylase, ursolic acid for PTP1B, and apigenin for α-glucosidase inhibition respectively. The LC-MS analysis also identified the presence of the above hit molecules in the hydroalcoholic extract.

CONCLUSION

The analogs of 3,4-dihydroxybenzoic acid, apigenin, and ursolic acid could be the choice of lead hits as the α-amylase, α-glucosidase, and PTP1B inhibitors respectively. Additionally, the majority of secondary metabolites from the hydroalcoholic extract of F. benghalensis may be involved in enhancing the glucose uptake to support the process of glycogenesis.

Evaluation of the Antidiabetic and Insulin Releasing Effects of A. squamosa, Including Isolation and Characterization of Active Phytochemicals

Annona squamosa is generally referred to as a 'custard apple'. Antidiabetic actions of hot water extract of Annona squamosa (HWAS) leaves together with isolation of active insulinotropic compounds were studied. Insulin release, membrane potential and intracellular Ca2+ were determined using BRIN-BD11 cells and isolated mouse islets. 3T3L1 adipocytes and in vitro models were used to determine cellular glucose uptake, insulin action, starch digestion, glucose diffusion, DPP-IV activity and glycation. Glucose intolerant high-fat fed rats were used for in vivo studies. Active compounds were isolated and characterized by HPLC, LCMS and NMR. HWAS stimulated insulin release from clonal β-cells and mouse islets. Using fluorescent indicator dyes and modulators of insulin secretion, effects could be attributed to depolarization of β-cells and influx of Ca2+. Secretion was stimulated by isobutylmethylxanthine (IBMX), tolbutamide or 30 mM KCl, indicating additional non-KATP dependent pathways. Extract stimulated cellular glucose uptake and insulin action and inhibited starch digestion, protein glycation, DPP-IV enzyme activity and glucose diffusion. Oral HWAS improved glucose tolerance and plasma insulin in high-fat fed obese rats. Treatment for 9 days with HWAS (250 mg/5 mL/kg), partially normalised energy intake, body weight, pancreatic insulin content, and both islet size and beta cell mass. This was associated with improved oral glucose tolerance, increased plasma insulin and inhibition of plasma DPP-IV activity. Isolated insulinotropic compounds, including rutin (C27H30O16), recapitulated the positive actions of HWAS on beta cells and in vivo glucose tolerance and plasma insulin responses. Annona squamosa is attractive as a dietary adjunct in treatment of T2DM and as a source of potential antidiabetic agents including rutin.

Hypoglycemic and antioxidant properties of konjac (Amorphophallus konjac) in vitro and in vivo

The aim of this study was to evaluate the hypoglycemic and antioxidant potential of konjac in vitro and in vivo. Glucose diffusion and enzymatic starch digestion of konjac were assayed using α-amylase and α-glucosidase. Oral glucose tolerance test (OGTT) and oral starch tolerance test (OSTT) were performed at dose of 102 mg/Kg of body weight (equivalent to 1 g/meal in humans). Additionally, the antioxidant activity of konjac was evaluated through inhibition of lipid peroxidation. The konjac decreased glucose diffusion by 36% and 19% compared with the negative and positive controls, respectively. Additionally, konjac inhibited α-amylase and α-glucosidase activities by 14% and 90%, respectively. After OSTT, group treated with konjac showed significant lower glucose levels compared with control group (p = .03). Finally, konjac reduced lipid peroxidation in human plasma (93%) compared with the negative control. Our results suggest that konjac exhibits hypoglycemic and antioxidant activities in vitro and in vivo. PRACTICAL APPLICATIONS: Because the use of herbal products have emerged as an attractive therapeutic option for chronic diseases, konjac administration may be an adjuvant for the treatment of type 2 diabetes.

Functional food and nutra-pharmaceutical perspectives of date (Phoenix dactylifera L.) fruit

Date palm counts among the oldest fruit crops of the world and is mainly cultivated for its highly nutritious fruits consumed as a staple food in many countries, especially in the Gulf region. Dates are enriched with numerous therapeutic bioactives and functional compounds such as phenolics, flavonols, carotenoids, minerals, and vitamins that not only provide an appreciable amount of energy required for the human body but also act as an effective therapeutic agent against several diseases. This review aimed to provide a deep insight into the nutritional as well as phytochemicals profile of date fruit and its seeds in order to explore their biological (anti-cancer, anti-diabetic, cardio-protective, anti-inflammatory properties), functional food, and nutra-pharmaceutical attributes. PRACTICAL APPLICATIONS: This review provides updated information regarding the date fruits and seeds phytochemicals composition together with highlighting dates potential as a natural therapeutic agent against several diseases. The study also urges the importance of consuming dates as a great package to live a healthy life due to the functional food and nutraceutical properties of this valuable fruit. The study also provides information first time as recommending dates to cope with the hidden hunger or micronutrient deficiency faced by the third world inhabitants. Hence, the review may further help the industry and researchers to explore the potential of dates for future medicinal and nutra-pharmaceutical applications.

Evaluation of the Antioxidant and Antidiabetic Potential of the Poly Herbal Formulation: Identification of Bioactive Factors

BACKGROUND AND OBJECTIVES

The present investigation is intended to prepare a Poly Herbal Formulation (PHF) with Piper nigrum (fruits), Terminalia paniculata (bark) and Bauhinia purpurea (bark) and assess their antioxidant and glucose-lowering effects utilizing in vitro models.

METHODS

The individual plant methanolic extracts and PHF are exposed to phytochemical examination and to distinguish the bioactive factors by GC-MS. We assessed the antioxidant properties of individual plant extracts and the PHF by using the DPPH scavenging method, H2O2 scavenging assay, TBARS assay and total antioxidant estimation. Likewise, the anti-diabetic activity was assessed by ɑ-amylase and α-glucosidase enzyme inhibition and glucose diffusion inhibitory techniques.

RESULTS

We found that PHF contains a high measure of total phenolics, total flavonoids and tannin compared to individual plant extracts. The GC-MS identified the bioactive components. We also found that PHF had significantly higher antioxidant and glucose-lowering effects than the individual plant concentrates.

CONCLUSION

In conclusion, it could be reasoned that due to the nearness of antioxidant components, the PHF has good potential in the administration of hyperglycemia, diabetes and the related state of oxidative stress. This study shows that PHF is superior to individual plant extracts, supporting the conventional PHF concept.

In-Vitro Antioxidant, Hypoglycemic Activity, and Identification of Bioactive Compounds in Phenol-Rich Extract from the Marine Red Algae Gracilaria edulis (Gmelin) Silva

Obesity and diabetes are major metabolic disorders which are prevalent worldwide. Algae has played an important role in managing these disorders. In this study, Gracilaria edulis, a marine red algae, was investigated for antioxidant and hypoglycemic potential using in vitro models. De-polysaccharide methanol extract of G. edulis was sequentially partitioned with hexane, chloroform, ethyl acetate, and antioxidants, and hypoglycemic potentials were evaluated using multiple methods. High antioxidant potential was observed in the ethyl acetate fraction in terms of ferric reducing antioxidant power, iron chelating, and DPPH and ABTS radical scavenging activities, while the crude methanol extract exhibited potent oxygen radical-absorbance capacity. Potent α-amylase inhibitory activity was observed in the ethyl acetate fraction, while the ethyl acetate fraction was effective against α-glucosidase inhibition. Glucose diffusion was inhibited by the ethyl acetate fraction at 180 min, and the highest antiglycation activity was observed in both chloroform and ethyl acetate fractions. Additionally, gas chromatography-mass spectrometry analysis of the ethyl acetate fraction revealed the presence of several potent anti-diabetic compounds. In conclusion, G. edulis exhibited promising antidiabetic potential via multiple mechanisms. The ethyl acetate fraction exhibited the strongest hypoglycemic and antiglycation potential among the four fractions, and hence the isolation of active compounds is required to develop leads for new drugs to treat diabetes.

Potency of Okra flour (Abelmoschus esculentus) in improving adiponectin level and total antioxidant capacity of high fat diet streptozotocin rat model

T2DM has increase in global-morbidity and mortality. Oxidative stress and adiponectin-levels are important for insulin-resistance and pancreatic-b-cell-dysfunction in T2DM. Okra fruit is rich of quercetin and phytosterol which have positive-effect for T2DM. Research aimed was to study the effect of okra-flour to adiponectin-levels and total-antioxidant-capacity (TAC) in T2DM. Thirty Wistar-rats were divided randomly in five groups. K1 and (X1, X2 and X3)-treated-groups were in T2DM-condition-induced by high-fat-diet-(HFD)-Streptozotochin-(STZ)-nicotinamid-(NA). Healthy-controls-(K2)-group was also used. Okra-flour was given orally for 28 days at doses of 0.1; 0.2 and 0.3 g/Kg-body-weight/d to X1, X2 and X3-groups, respectively. Statistical program was used to analyse the different between pre-post-intervention, and between groups. Correlations between variables were also analysed. The serum-adiponectin and TAC-levels were measured by ELISA and ABTS-methods, respectively. By comparing pre and post-intervention, adiponectin levels of all-intervention-(X1, X2, X3)-group were  increase (p = 0.027 for X1 and X2; p = 0.028 for X3), while in the same period the decrease were found in group K1 (p = 0.026) and K2 (p = 0.028). Increase-TAC-levels pre-post-intervention was observed in group all-intervention-groups (p = 0.027), while no change in K1 (p = 0.66) and the decrease in group K2 (p = 0.039). Reduce-fasting-blood-glucose-levels pre-post-intervention were shown in the all-intervention-groups (p = 0.028), while for the K1 groups was increase (p = 0.028). There were significant differences between the five-groups on fasting-blood-glucose-levels, adiponectin and TAC-levels, and X3-group showed the highest adiponectin and TAC-levels. Very-strong-correlations were found between glucose-adiponectin-TAC-levels-post-intervention. Okra-flour make better glucose-adiponectin and TAC-levels in T2DM-conditions. Okra dose of 0.30 g/Kg-body-weight/day is the best in increasing adiponectin and TAC-levels.

Antidiabetic, antioxidant and antimicrobial activities of extracts of Tephrosia bracteolata leaves

AIMS

Plant extracts have long been used for the ethnomedical treatment of diabetes, microbial infections and as a source of antioxidant. This study was aimed at investigating the antidiabetic, antioxidant, and antimicrobial activities of the n-hexane and ethyl acetate extract of Tephrosia bracteolata leaves (TBL) as associated with the ethnobotanical knowledge of the local people of Nigeria.

MAIN METHODS

The phytochemical composition of the n-hexane and ethyl acetate extract of the leaves of T. bracteolata were determined following standard procedures in literature, and it's in vitro inhibitory activities against α-glucosidase enzyme. 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS.+) and 1,1-diphenyl-2-picrylhydrazyl (DPPH+) antioxidant activities were also examined. Well diffusion method was employed in evaluating the antimicrobial property of the extracts.

KEY FINDINGS

The ethyl acetate extract of T. bracteolata leaves had the greatest inhibitory effect on α-glucosidase, followed by the n-hexane with IC50 43.95 μg/ml and IC50 ˃50 μg/ml respectively. The ethyl acetate also exhibited significant DPPH+ and ABTS.+ antioxidant activity with IC50 of 24.96 μg/ml and 6.48 μg/ml as compared to Ascorbic acid and Trolox (12.24 μg/ml and 5.91 μg/ml) respectively. The zones of inhibition of the ethyl acetate extract of T. bracteolata leaves ranges from 10 - 25 mm at a concentration of 6.25-200 mg/ml, and it showed a greater antibacterial activity than the n-hexane extract, having a zone of inhibition from 10 - 20 mm at concentration of 12.5-200 mg/ml when compared to the standard Gentamycin. Similarly, the ethyl acetate extract of T. bracteolata showed a better anti fungi activity at concentration range 12.5-200 mg/ml than the n-hexane extract at concentration range of 25-200 mg/ml with reference to Tioconazole. These results indicated for the first time that the ethyl acetate extract of T. bracteolata leaves extracts exerted potent inhibitory effects against α-glucosidase, actively scavenge DPPH+ and ABTS.+ free radicals and successfully inhibits the proliferation of Gram positive and Gram negative microorganism.

SIGNIFICANCE

TBL is an important source of antidiabetic, antimicrobial and antioxidant agent.

Raffia palm (Raphia hookeri) wine inhibits glucose diffusion; improves antioxidative activities; and modulates dysregulated pathways and metabolites in oxidative pancreatic injury

Raffia palm wine is a natural drink from the stem of Raffia palm (Raphia hookeri) tree with nutritional and medicinal properties. The effect of fermentation was investigated on its antidiabetic and antioxidative effects in yeast cells and pancreatic tissues, respectively. Both unfermented and fermented palm wine significantly increased glucose uptake, reduced glutathione level (GSH), superoxide dismutase, and catalase activities. They also inhibited glucose diffusion, myeloperoxidase, and ATPase activities as well as decreased malondialdehyde and nitric oxide levels. They also led to the inactivation of oxidative metabolic pathways in oxidative pancreas with the generation of adenosine, sugar and inositol metabolites, selenium (enzyme co-factor) and vitamin metabolites owing to concomitant activation of vitamins, lipid, steroids, inositol, and sulfate/sulfite metabolic pathways. The results suggest the antidiabetic and antioxidative potentials of unfermented and fermented palm wine and may be attributed to the LC-MS-identified compounds which were mainly polyphenols and its glycosides, vitamins, and amino acids. PRACTICAL APPLICATIONS: Raffia palm wine is among the natural beverages employed for social, nutritional, and medicinal purposes. However, there are limited studies on its medicinal properties. This study reports for the first time, the ability of Raffia palm wine to stimulate glucose uptake, inhibit glucose diffusion, and ameliorate pancreatic oxidative injury, as well as the possible associated metabolic pathways that may be involved. These findings will further contribute in understanding the antidiabetic effect of Raffia palm wine, and the possible metabolic pathways involved.

Tunisian Clematis flammula Essential Oil Enhances Wound Healing: GC-MS Analysis, Biochemical and Histological Assessment

The aerial part of Clematis flammula (Ranunculaceae) has been traditionally used in the treatment of skin diseases including mycotic infection in the Tunisian traditional medicine. The study was undertaken to extract and determine the essential oil chemical composition of Clematis flammula aerial parts and to assess the potential of anemonin in wound healing on mechanically wounded wistar rats. The essential oil was obtained by hydrodistillation and analyzed by GC-MS. Anemonin was isolated and then incorporated as active in a cream for which the cytotoxicity was evaluated by methyl thiazolyl tetrazolium (MTT)-based colorimetric assay. Then, its potential in wound healing on mechanically wounded wistar rats was assessed. The GC-MS analysis showed that the major compound was protoanemonin (86.74%) which spontaneously dimerised in part to form the anemonin. The wound healing activity of anemonin cream exhibited a non toxic potential of anemonin at a concentration of 25 µg/mL with a cell migration efficiency that reaches more than 80% after 48 hours of treatment. Wound healing efficiency was evaluated by monitoring morphological and skin histological analyses. Comparable wound surface reduction of the group treated by anemonin cream (p ≥ 0.05) when compared to the reference treated group. The skin histological analysis showed the completely wound closure. Antioxidant activity was assessed by the malondialdehyde (MDA) rates and antioxidant enzymes (glutathione peroxidase (GPx) and catalase) determination. The results provided strong support for the effective wound healing activity of anemonin cream, making it a promising candidate as a therapeutic agent in tissue repairing processes.

The therapeutics effects and toxic risk of Heracleum persicum Desf. extract on streptozotocin-induced diabetic rats

There is an increasing interest against to fight of diabetes by using hypoglycemic plants in the world. The public thinks that Heracleum persicum (HP) has antidiabetic effect local consumer in Turkey. As far as our literature survey, no studies have been reported so far on antidiabetic effects and toxic risk potential of the HP lyophilized extract supplementation used in this study. The aim of this study, for the first time, was to investigate the therapeutic effects of diabetic complications, antioxidant properties and toxic risk potential of HP against experimentaly streptozotocin (STZ) induced diabetes in rats, which were evaluated by measuring the level of serum biomarker releated diabetes complications changes such glucose, insülin, c-peptide, lipid profile (LP), hepatic and renal damage biomarkers (HRDB), glucosylated hemoglobin (HbA1c), antioxidant defense system constituents (ADSCs), malondialdehyde (MDA) content measured in erythrocyte, brain, kidney and liver tissues, and α-glucosidase activitiy of small intestine. The plant aqueous extract was allowed to freeze-dried under a vacuum at -54 °C to obtain a fine lyophilized extract. The study was performed on STZ-induced diabetic rats (45 mg/kg, body weight (bw), intraperitonally) designed as normal control (NC), diabetic control (DC), diabetes + acarbose (DAC) (20 mg/kg, bw), diabetes + HP (100 mg/kg, bw) (DH1), diabetes + HP (200 mg/kg, bw) (DH2) and diabetes + HP (400 mg/kg, bw) (DH3)] groups. The experimental process lasted 21 days. According to results; the levels of blood glucose (BG), glucosylated hemoglobin (HbA1c) and malondialdehyde (MDA) of DC group increased significantly (p<0.05) compared to NC group, whereas these parameters of the groups treated with oral administrations of HP plant lyophilized extract were observed significant (p<0.05) declines compared to DC. The biochemical analyses showed a considerable decrease in insulin and c-peptide levels and the fluctuated ADSCs in the DC group as compared to control group, whereas the extract supplementations diet restored the diabetic complications parameters towards to the NC. On the other hands, liver damage serum enzymes as serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were incressed significantly (p<0.05) in the plant extract supplementations groups as compared to NC and DC groups. It was concluded that while the extracts of HP have had therapeutic effects on some complications caused by diabetes, but might be caused hepatocyte damage changes as the transport functions and membrane permeability of these cells, thus causing enzymes to leak.

Lipid peroxidation diminishing perspective of isolated theaflavins and thearubigins from black tea in arginine induced renal malfunctional rats

BACKGROUND

Recently oxidative stress induced maladies have amplified owing to sedentary lifestyle and monotonous diet. Introduction of plant based biomolecules may be a suitable strategy to cope with the lipid peroxidation. In this context, black tea polyphenols (theaflavin & thearubigins) are in fame among the scientific community as cost effective therapeutic agents owing to their safety, economics, structural diversity and ability to modulate various lipid peroxidation responses by halting the expression of different metabolic targets.

METHODS

The mandate of present investigation was to first time check the synergism among the isolated theaflavins & thearubigins against lipid peroxidative indicators both in vitro and in vivo. Purposely, theaflavins and thearubigins were isolated from black tea through solvent partition methods by using different solvents (Aqueous ethanol, Aqueous methanol & Water) and time intervals (30, 60 & 90 min) and subjected to in vitro characterization through different antioxidant indices to access the in vitro lipid peroxidation shooting effect of these bioactive moieties. Moreover, individual theaflavins contents also estimate through HPLC. For evaluation of in vivo antioxidant effect, renal malfunction was induced through arginine and forty rats were divided in four groups (10 each after power analysis) and 04 types of diets were given i.e. T0 (control diet without supplementation), T1 (Basic experimental Diet+ theaflavins supplementation @ 1 g), T2 (Basic experimental Diet+ Thearubigins supplementation @ 1 g) & T3 (Basic experimental Diet+ Supplementation of theaflavins+ thearubigins @ 0.5 + 0.5 g, respectively) for the period of 56 days. Alongside, a control study was also carried out for comparison by involving normal rats fed on arginine free diet. The body weight, lipid profile, glycemic responses, Renal function test, liver function test, antioxidant indices and hematological parameters were estimated at the termination of study.

RESULTS

The results indicated that theaflavins and thearubigins isolation was significantly affected by time of extraction and solvent. In this context, aqueous ethanol at 60 min extraction interval caused maximum extraction. Likewise, theaflavins isolate exhibited more antioxidant activity as compared to thearubigins. Moreover, the theaflavins and thearubigins based experimental diets imparted significant reduction in Lipid profile, glucose content, renal function tests and TBARS with enhancement in insulin, HDL and hematological parameters. In this context, theaflavin based diet caused maximum reduction in lipid profile and TBARS better as compared to thearubigins and theaflavins + thearubigins based. However, theaflavin+ thearubigins based diet caused highest glucose, urea & creatinine decline and maximum insulin increase & antioxidant indices as compared to other nutraceuticals.

CONCLUSIONS

It was deduced that theaflavins & thearubigins have strong antioxidative potential both in in vitro as well as in vivo to tackle the menace associated with lipid peroxidation.

Antiobesity and antihyperglycaemic effects of Adiantum capillus-veneris extracts: in vitro and in vivo evaluations

CONTEXT

Adiantum capillus-veneris L. (Adiantaceae) hypocholesterolemic activity is therapeutically praised.

OBJECTIVES

Pharmacological modulation of pancreatic triacylglycerol lipase (PL) and α-amylase/α-glucosidase by A. capillus-veneris are evaluated.

MATERIALS AND METHODS

Using positive controls (acarbose, orlistat, guar gum, atorvastatin, glipizide and metformin) as appropriate, crude aqueous extracts (AEs) of A. capillus-veneris aerial parts were tested via a combination of in vitro enzymatic (0.24-100 mg/mL), acute in vivo carbohydrate tolerance tests (125, 250 or 500 mg/kg body weight [b.wt]) and chronic in vivo studies (500 mg/kg b.wt) in high cholesterol diet (HCD) fed Wistar rats.

RESULTS

Like acarbose, A. capillus-veneris as well as chlorogenic acid, with respective IC₅₀ values (mg/mL) of 0.8 ± 0.0 and 0.2 ± 0.0, were identified as in vitro potent dual inhibitors of α-amylase/α-glucosidase. Unlike guar gum, A. capillus-veneris had no glucose diffusion hindrance capacity. Equivalent to orlistat, A. capillus-veneris and its phytoconstituents inhibited PL in vitro with an ascending order of PL- IC₅₀ values (μg/mL): ferulic acid; 0.48 ± 0.06 < ellagic acid; 13.53 ± 1.83 < chlorogenic acid; 38.4 ± 2.8 < A. capillus-veneris; 1600 ± 100. Incomparable to acarbose or metformin and glipizide, A. capillus-veneris (125, 250 and 500 mg/kg b.wt) lacked antihyperglycaemic efficacies in acute starch- or glucose-evoked postprandial hyperglycaemia increments in normoglycaemic overnight fasting rats. Superior to atorvastatin; A. capillus-veneris exerted significant antiobesity (p < 0.001) with marked triacylglycerol-reducing capacities (p < 0.001) in comparison to rats fed with HCD for 10 weeks.

DISCUSSION AND CONCLUSION

A. capillus-veneris, modulating pancreatic digestive enzymes, may be advocated as a combinatorial diabesity prevention/phytotherapy agent.

Coriander (Coriandrum sativum): A promising functional food toward the well-being

Coriandrum sativum (C. sativum) or coriander is one of the most popularly used spices in culinary worldwide, and its medicinal values has been recognized since ancient time. C. sativum contains bioactive phytochemicals that are accounted for a wide range of biological activities including antioxidant, anticancer, neuroprotective, anxiolytic, anticonvulsant, analgesic, migraine-relieving, hypolipidemic, hypoglycemic, hypotensive, antimicrobial, and antiinflammatory activities. The major compound, linalool, abundantly found in seeds is remarked for its abilities to modulate many key pathogenesis pathways of diseases. Apart from the modulating effects, the potent antioxidant property of the C. sativum provides a key mechanism behind its protective effects against neurodegenerative diseases, cancer, and metabolic syndrome. This review shed light on comprehensive aspects regarding the therapeutic values of the C. sativum, which indicate its significance of being a promising functional food for promoting the well-being in the era of aging and lifestyle-related diseases.