Natural products used for diabetes

Natural hypoglycaemic bioactives: Newer avenues and newer possibilities

The incidences of endocrine and metabolic disorders like diabetes have increased worldwide. Several proposed molecular pathways mechanisms for the management of diabetes have been identified, but glycaemic control is still a challenging task in the drug discovery process. Most of the drug discovery processes lead to numerous scaffolds that are prominent in natural products. The review deals with the natural bioactives as an α-amylase inhibitors, α-glucosidase inhibitors, protein tyrosine phosphatase-1B inhibitors, dipeptidyl peptidase-IV inhibitors, G-protein coupled receptors-40 agonists, PPAR-γ agonists and the activators of 5'-adenosine monophosphate-activated protein kinase and glucokinase. So, in this review, we focused on the hypoglycaemic bioactives, which will assist scientific developers, traditional medicinal practitioners, and readers to discover some potent antidiabetic molecules. Strategies like chemometric approaches, scaffold hopping, and total synthesis of natural products by group modification or ring opening/closing mechanism could be useful for the development of novel hit/lead antidiabetic molecules. The study concludes that each phyto molecule inherits a potential to get explored by repurposing techniques for various antidiabetic targets and offer an alternative antidiabetic therapeutic medicinal potential.

Antidiabetic Evaluation of Kigelia pinnata Root Bark Extract in Streptozotocin-Induced Type-2 Diabetes Model of Rats

Diabetes mellitus (DM) is the most common endocrine disorder characterized by increased blood glucose levels resulting from defective insulin secretion, resistance to insulin action, or both. DM is often associated with severe complications, and there is an increasing appreciation that cognitive function declines in DM. The aim of this research work was to evaluate Kigelia pinnata root bark extract in Streptozotocin (STZ)-induced type-2 diabetes. Experimental diabetes was induced by a single administration of STZ (60 mg/kg, intraperitoneal [i.p.]), immediately after the STZ administration, and all animals were fed with normal food and water. Nicotinamide was administered (120 mg/kg, i.p.) 15 min before STZ. The development of hyperglycemia was confirmed by the elevated blood glucose levels determined at fixed intervals, which was confirmed by measuring fasting blood glucose levels in rats' blood taken from the tail vein. Supplementation with ethanolic extract of K. pinnata root bark (EEKP) significantly reduced the elevated blood glucose in STZ-induced hyperglycemia in rats. EEKP significantly restored the biochemical and antioxidant defense system. On the final day of the protocol, the extract also reduced inflammatory cytokines in the blood serum.

Physicochemical, Nutritional, and Medicinal Properties of Opuntia ficus-indica (L.) Mill. and Its Main Agro-Industrial Use: A Review

The cactus, Opuntia ficus-indica (L.) Mill. (OFI) belongs to the Cactaceae family, which contains about 130 genera and nearly 1600 species. This review aims to evaluate this plant from several perspectives, namely, botanic, physicochemical, nutritional, and medicinal properties, as well as agro-industrial use. The botanical aspects and morphological characteristics of OFI enable genetic variability, ecological adaptation, and broad geographic distribution. Due to its physicochemical and nutritional composition, it has several medicinal properties appropriate (or suitable) for several industries, such as pharmaceutical, food, and cosmetics. Its fruit, the prickly pear (PP), has potential agro-industrial expansion through the application of different conservation and transformation methods, making it possible to obtain a variety of products. The PP is a source of several nutrients and is an effective system to produce varied foods, which have several advantages from a nutritional, sensory, economic, and shelf-life point of view.

(1'S)-1'-Acetoxyeugenol Acetate Enhances Glucose-Stimulated Insulin Secretion

Alpinia galanga have been widely used as spice or traditional medicine in East Asia, commonly known as Thai ginger. In the present study, seven major phenylpropanoids, (±)-1'-hydoxychavicol acetate (1; HCA), (1'S)-1'-acetoxychavicol acetate (2; ACA), (1'S)-1'-acetoxyeugenol acetate (3; AEA), eugenyl acetate (4), trans-p-coumaraldehyde (5), trans-p-acetoxycinnamyl alcohol (6), and trans-p-coumaryl diacetate (7), were isolated from the 95% EtOH and hot water extracts of the rhizomes of A. galanga by chromatographic method. Phenylpropanoids 1-7 were evaluated for glucose-stimulated insulin secretion (GSIS) effect and α-glucosidase inhibitory activity. Phenylpropanoids 1-4 increase GSIS effect without cytotoxicity in rat INS-1 pancreatic β-cells. In addition, INS-1 cells were treated with AEA (3) to determine a plausible mechanism of β-cell function and insulin secretion through determining the activation of insulin receptor substrate-2 (IRS-2), phosphatidylinositol 3-kinase (PI3K), Akt, and pancreatic and duodenal homeobox-1 (PDX-1). Upon treatment with AEA (3), INS-1 cells showed an increase in these protein expressions. Meanwhile, AEA (3) exhibited α-glucosidase inhibitory activity. On the basis of the above findings, we suggest AEA (3) as a potential antidiabetic agent.

Cross-Talk between Obesity and Diabetes: Introducing Polyphenols as an Effective Phytomedicine to Combat the Dual Sword Diabesity

: Obesity-associated diabetes mellitus, a chronic metabolic affliction accounting for 90% of all diabetic patients, has been affecting humanity extremely badly and escalating the risk of developing other serious disorders. It is observed that 0.4 billion people globally have diabetes, whose major cause is obesity. Currently, innumerable synthetic drugs like alogliptin and rosiglitazone are being used to get through diabetes, but they have certain complications, restrictions with severe side effects, and toxicity issues. Recently, the frequency of plant-derived phytochemicals as advantageous substitutes against diabesity is increasing progressively due to their unparalleled benefit of producing less side effects and toxicity. Of these phytochemicals, dietary polyphenols have been accepted as potent agents against the dual sword "diabesity". These polyphenols target certain genes and molecular pathways through dual mechanisms such as adiponectin upregulation, cannabinoid receptor antagonism, free fatty acid oxidation, ghrelin antagonism, glucocorticoid inhibition, sodium-glucose cotransporter inhibition, oxidative stress and inflammation inhibition etc. which sequentially help to combat both diabetes and obesity. In this review, we have summarized the most beneficial natural polyphenols along with their complex molecular pathways during diabesity.

Opuntia genus in Human Health: A Comprehensive Summary on Its Pharmacological, Therapeutic and Preventive Properties. Part 1

Opuntia spp. is a diverse and widely distributed genus in Africa, Asia, Australia, and America. Mexico has the largest number of wild species; mainly O. streptacantha, O. hyptiacantha, O. albicarpa, O. megacantha and O. ficus-indica. The latter being the most cultivated and domesticated species. Throughout history, plants and their phytochemicals have played an important role in health care and Opuntia spp. has shown a high nutritional, medicinal, pharmaceutical, and economic impacts. Its main bioactive compounds include pigments (carotenoids, betalains and betacyanins), vitamins, flavonoids (isorhamnetin, kaempferol, quercetin) and phenolic compounds. Together, they favor the different plant parts and are considered phytochemically important and associated with control, progression and prevention of some chronic and infectious diseases. This first review (Part 1), compiles information from published research (in vitro, in vivo, and clinical studies) on its preventive effects against atherosclerotic cardiovascular diseases, diabetes and obesity, hepatoprotection, effects on human infertility and chemopreventive and/or antigenotoxic capacity. The aim is to provide scientific evidences of its beneficial properties and to encourage health professionals and researchers to expand studies on the pharmacological and therapeutic effects of Opuntia spp.

Propolis Can Improve Caudal Fin Regeneration in Zebrafish (Danio rerio) Induced by The Combined Administration of Alloxan and Glucose

Hyperglycemia, a primary symptom in diabetes mellitus, is associated with difficulties in wound healing and regeneration. This condition is due to the length of the inflammatory phase and free radicals. Furthermore, there is evidence that molecular pathogenesis is involved in impaired wound healing in diabetics. As an animal model, zebrafish have many shared orthologous genes with human that are involved in protein regulation of wound healing and regeneration. Little is known about natural drugs that may be used to treat complications of wound healing in diabetes. Propolis, however, is known to consist of various organic compounds such as phenols and flavonoids with antioxidant and anti-inflammatory activities. This research aims to study propolis' effect on caudal fin regeneration and relative expression of several genes belonging to Hedgehog, bone morphogenetic protein (BMP), and Wnt signaling hyperglycemic (HG) zebrafish. GC-MS analysis and antioxidant activity testing were performed on ethanolic extract of propolis (EEP). Caudal fin regeneration was analyzed using ImageJ; blood glucose levels were measured; and relative gene expression analysis of shha, igf2a, bmp2b, and col1a2 was performed by the real-time polymerase chain reaction method with the β-actin housekeeping gene. Impairment of caudal fin regeneration in zebrafish hyperglycemia was characterized by a low percentage of regeneration and decreased relative gene expression. EEP at 15 ppm could increase the percentage of caudal fin regeneration and the expression of shha, igf2a, bmp2b, and col1a2. Based on the results, it appears that phenols and flavonoids from the EEP can improve the caudal fin regeneration of HG zebrafish.

Synergistic effects of high-intensity interval training (HIIT) and intake of nettle on serum levels of chemerin and beta cells function in type 2 diabetic rats

OBJECTIVES

This animal study aimed to demonstrate the synergistic effect of high-intensity interval training (HIIT) and alcoholic extract of nettle on serum chemerin and beta cells function in type 2 diabetic male rats.

METHODS

Thirty-two STZ-induced diabetic male Wistar rats were randomly divided into four groups including the control group, the supplemented group with 200 mg/day of nettle, the training group with five sessions per week of HIIT, and the group with combined nettle and HITT intervention. Body weight, lipid profile, beta cells function, and chemerin level were assessed after eight weeks of the intervention.

RESULTS

The values of chemerin significantly decreased in combined HIIT and nettle intervention group compared to the control group (p=0.001). The levels of glucose and insulin decreased significantly in nettle group, exercise group, and combined HIIT and nettle group (p=0.001).

CONCLUSIONS

The present study found that intense interval exercise with the consumption of alcoholic extract of nettle can affect the performance of beta cells, glucose, and insulin. Future human studies are warranted.

5-Bromoprotocatechualdehyde Combats against Palmitate Toxicity by Inhibiting Parkin Degradation and Reducing ROS-Induced Mitochondrial Damage in Pancreatic β-Cells

Pancreatic β-cell loss is critical in diabetes pathogenesis. Up to now, no effective treatment has become available for β-cell loss. A polyphenol recently isolated from Polysiphonia japonica, 5-Bromoprotocatechualdehyde (BPCA), is considered as a potential compound for the protection of β-cells. In this study, we examined palmitate (PA)-induced lipotoxicity in Ins-1 cells to test the protective effects of BPCA on insulin-secreting β-cells. Our results demonstrated that BPCA can protect β-cells from PA-induced lipotoxicity by reducing cellular damage, preventing reactive oxygen species (ROS) overproduction, and enhancing glucose-stimulated insulin secretion (GSIS). BPCA also improved mitochondrial morphology by preserving parkin protein expression. Moreover, BPCA exhibited a protective effect against PA-induced β-cell dysfunction in vivo in a zebrafish model. Our results provide strong evidence that BPCA could be a potential therapeutic agent for the management of diabetes.

Antidiabetic effect of aqueous-ethanol extract from the aerial parts of Artemisia roxburghiana

Artemisia roxburghiana is used for the management of diabetes mellitus in the Indian subcontinent. The present work aimed to validate the traditional claim of the plant in diabetes mellitus. In vitro studies were conducted using α-glucosidase and α-amylase assays whereas streptozotocin-nicotinamide-induced diabetic Wistar rats were used for in vivo study. The aqueous-ethanol extract from the aerial parts was found to exhibit α-glucosidase and α-amylase inhibitory activities with the IC₅₀ values of 31.0 and 17.2 mg/mL, respectively when compared with acarbose (IC₅₀ = 8.6 and 16.25 mg/mL, respectively). The extract showed a significant glucose-lowering effect in diabetic rats at the doses of 200 and 400 mg/kg in a dose-dependent manner, while acarbose (10 mg/kg) was used as a standard. The results revealed that A. roxburghiana aerial parts showed antidiabetic activity via inhibiting α-glucosidase and α-amylase enzymes. The present study also validated the ethnomedicinal claim of the plant in diabetes mellitus.

Pasta Supplemented with Opuntia ficus-indica Extract Improves Metabolic Parameters and Reduces Atherogenic Small Dense Low-Density Lipoproteins in Patients with Risk Factors for the Metabolic Syndrome: A Four-Week Intervention Study

Food supplementation with Opuntia ficus-indica (OFI) has been associated with a significant reduction in total cholesterol, body fat, hyperglycemia and blood pressure. Since OFI may also have antioxidant and anti-atherogenic properties, we hypothesized that its supplementation might reduce atherogenic lipoproteins, including small, dense low-density lipoproteins (sdLDL). Forty-nine patients (13 men and 36 women, mean age: 56 ± 5 years) with one or two criteria for the metabolic syndrome weekly consumed 500 g of pasta supplemented with 3% OFI extract (30% of insoluble polysaccharides with high antioxidant power) for 1 month. The full LDL subclass profile was assessed by gel electrophoresis (Lipoprint, Quantimetrix, Redondo Beach, CA, USA). After 1 month of pasta supplementation, waist circumference (p = 0.0297), plasma glucose (p < 0.0001), triglycerides (p = 0.0137), plasma creatinine (p = 0.0244), urea and aspartate transaminase (p < 0.0001 for each) significantly decreased. A percentage increase in larger, less atherogenic LDL-1 (p = 0.0002), with a concomitant reduction in smaller, denser LDL-2 (p < 0.0001) and LDL-3 (p = 0.0004), were found. LDL-4 and-5 decreased, although not significantly. This is the first intervention study suggesting that pasta enriched with an OFI extract may have beneficial effects on some metabolic parameters and the LDL particle sizes, reducing atherogenic sdLDL. Future studies will help to establish if these findings impact cardiovascular outcomes.

Natural products in diabetes research: quantitative literature analysis

The current study aimed to identify which natural products and which research directions are related to the major contributors to academic journals for diabetes therapy. Bibliometric data were extracted from the Web of Science online database using the search string TOPIC = (''natural product*' OR ''natural compound*' OR ''natural molecule*' OR 'phytochemical*' OR ''secondary metabolite*') AND TS = ('diabet*') and analysed by a bibliometric software, VOSviewer. The search yielded 3694 publications, which were collectively cited 80,791 times, with an H-index of 117 and 21.9 citations per publication on average. The top-contributing countries were India, the USA, China, South Korea and Brazil. Curcumin, flavanone, resveratrol, carotenoid, polyphenols, flavonol, flavone and berberine were the most frequently cited natural products or compound classes. Our results provide a brief overview of the major directions of natural product research in diabetes up to now and hint on promising avenues for future research.

In Vitro Hypoglycemic and Radical Scavenging Activities of Certain Medicinal Plants

The purpose of this study is to investigate in vitro hypoglycemic and free radical scavenging activities of some medicinal plants including Ficus glomerata (FG), Pandanus amaryllifolia (PaA), Artocarpus altilis (AA), Gomphrena celosioides (GC) and Gynostemma pentaphyllum (GP). Alpha-amylase inhibitory assay was examined by dinitrosalicylic acid reaction. Glucose up-take assay was investigated by LO-2 cell model. DPPH and ABTS+ scavenging assays were performed by spectrophotometry. Cell viability was determined by MTT method. It was found that the extracts including FG, PaA, AA, GC and GP were able to inhibit alpha-amylase activity up to 38.4 ± 4.2%, 47.8 ± 4.3%, 49.3 ± 3.5%, 40.1 ± 4.4% and 38.5 ± 3.8%, respectively. Moreover, glucose adsorption and glucose uptake capacity of these extracts were evidenced. In addition, free radical scavenging activity of these extracts was indicated in a range of 30.6-54.5% for DPPH radical and 31.8-51.1% for ABTS+ radical. Especially, these extracts exhibited no cytotoxicity effect on human hepatic LO-2 cells and human gastric BGC-823 cells at the concentration of 100 µg/ml. The results indicated that A. altilis leaves were effective in inhibiting alpha-amylase activity, increasing glucose adsorption and glucose uptake and scavenging free radicals. Therefore, it could be suggested to be a promising hypoglycemic agent for managing type 2 diabetes.

A systematic analysis of natural α-glucosidase inhibitors from flavonoids of Radix scutellariae using ultrafiltration UPLC-TripleTOF-MS/MS and network pharmacology

BACKGROUND

Flavonoids from plant medicines are supposed to be viable alternatives for the treatment of type 2 diabetes (T2D) as less toxicity and side effects. Radix scutellariae (RS) is a widely used traditional medicine in Asia. It has shown great potential in the research of T2D. However, the pharmacological actions remain obscured due to the complex chemical nature of plant medicines.

METHODS

In the present study, a systematic method combining ultrafiltration UPLC-TripleTOF-MS/MS and network pharmacology was developed to screen α-glucosidase inhibitors from flavonoids of RS, and explore the underlying mechanism for the treatment of T2D.

RESULTS

The n-butanol part of ethanol extract from RS showed a strong α-glucosidase inhibition activity (90.55%, IC50 0.551 mg/mL) against positive control acarbose (90.59%, IC50 1.079 mg/mL). A total of 32 kinds of flavonoids were identified from the extract, and their ESI-MS/MS behaviors were elucidated. Thirteen compounds were screened as α-glucosidase inhibitors, including viscidulin III, 2',3,5,6',7-pentahydroxyflavanone, and so on. A compound-target-pathway (CTP) network was constructed by integrating these α-glucosidase inhibitors, target proteins, and related pathways. This network exhibited an uneven distribution and approximate scale-free property. Chrysin (k = 87), 5,8,2'-trihydroxy-7-methoxyflavone (k = 21) and wogonin (k = 20) were selected as the main active constituents with much higher degree values. A protein-protein interaction (PPI) weighted network was built for target proteins of these α-glucosidase inhibitors and drug targets of T2D. PPARG (Cd = 0.165, Cb = 0.232, Cc = 0.401), ACACB (Cd = 0.155, Cb = 0.184, Cc = 0.318), NFKB1 (Cd = 0.233, Cb = 0.161, Cc = 0.431), and PGH2 (Cd = 0.194, Cb = 0.157, Cc = 0.427) exhibited as key targets with the highest scores of centrality indices. Furthermore, a core subnetwork was extracted from the CTP and PPI weighted network. Type II diabetes mellitus (hsa04930) and PPAR signaling pathway (hsa03320) were confirmed as the critical pathways.

CONCLUSIONS

These results improved current understanding of natural flavonoids on the treatment of T2D. The combination of ultrafiltration UPLC-TripleTOF-MS/MS and network pharmacology provides a novel strategy for the research of plant medicines and complex diseases.

Mechanisms of Herbal Nephroprotection in diabetes mellitus

Diabetic nephropathy (DN) is a leading cause of kidney morbidity. Despite the multilayered complexity of the mechanisms involved in the pathogenesis of DN, the conventional treatment is limited to just a few drug classes fraught with the risk of adverse events, including the progression of renal dysfunction. Phytoceuticals offer a promising alternative as they act on the many-sidedness of DN pathophysiology, multitargeting its intricacies. This paper offers a review of the mechanisms underlying the protective action of these phytoagents, including boosting the antioxidant capabilities, suppression of inflammation, averting the proliferative and sclerosing/fibrosing events. The pathogenesis of DN is viewed as a continuum going from the original offense, high glucose, through the noxious products it generates (advanced glycation end-products, products of oxidative and nitrosative stress) and the signaling chains consequently brought into action, to the harmful mediators of inflammation, sclerosis, and proliferation that eventually lead to DN, despite the countervailing attempts of the protective mechanisms. Special attention was given to the various pathways involved, pointing out the ability of the phytoagents to hinder the deleterious ones (especially those leading to, driven by, or associated with TGF-β activation, SREBP, Smad, MAPK, PKC, NF-κB, NLRP3 inflammasome, and caspase), to promote the protective ones (PPAR-α, PPAR-γ, EP4/Gs/AC/cAMP, Nrf2, AMPK, and SIRT1), and to favorably modulate those with potentially dual effect (PI3K/Akt). Many phytomedicines have emerged as potentially useful out of in vitro and in vivo studies, but the scarcity of human trials seriously undermines their usage in the current clinical practice-an issue that stringently needs to be addressed.

Effect of Wheat Straw as a Cover Crop on the Chlorophyll, Seed, and Oilseed Yield of Trigonella foeunm graecum L under Water Deficiency and Weed Competition

The effects of water stress on fenugreek crops are well documented. However, little is known about how these plants respond to water deficits under a soil-mulching system when the surface is protected. Therefore, the current research aims to demonstrate the possibility of reducing the impact of water stress and weed competition on the fenugreek crop through the use of wheat residues as a cover crop on the soil surface. A field experiment was carried out during the winter season (2016-2017) using a split-plot design arrangement with three replicates. The experiments included four levels of water deficit, which consisted of a 40% depletion treatment as a control plot, and 50%, 60%, and 70% depletion from the field capacity (DFC) for the other studied fields. The subplot division consisted of mulching the soil with wheat residues. The results demonstrated that soil-mulching systems and a water deficit are able to impact the fenugreek yield of seed and oil. Additionally, soil mulching led to a decrease in weed density and biomass, chlorophyll content, and biological yield. Although high water deficit (70% DFC) led to yield and growth reduction, the use of wheat residue as a cover crop moderated the effect of a strong water deficit on plants and showed clear reduction of weed growth. Therefore, the results suggest that soil mulching can mitigate the adverse effects of water deficit by conserving soil moisture and decreasing weeds, which can be considered an acclimation mechanism under water-deficit conditions to avoid yield loss. Moreover, the allelopathic effects of wheat residue were observed on fenugreek crops subjected to irrigation after depleting 40% soil water moisture, but these effects disappeared within 90 days of sowing. We conclude that these results can help future agricultural planning and systems in order to increase productivity, reduce irrigation costs, and conserve soil quality.

Phytochemicals and antidiabetic activity of the aqueous extract of the Punica granatum fruit in streptozotocin-induced diabetic mice

The present study investigated the phytochemicals and antidiabetic effect of the aqueous extract of the fruit of Punica granatum Linn. in streptozotocin (STZ)-induced diabetic mice. The fruit of P. granatum was extracted with water. The phytochemicals of the water extract were investigated by the liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. The water extract of P. granatum at doses of 150 and 300 mg/kg body weight (bw) was administered to mice for 21 days, and blood glucose level, triglyceride, total cholesterol, low-density lipoprotein (LDL)-cholesterol, high-density lipoprotein-cholesterol, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) enzyme were estimated. Analyzed phytochemicals showed the fruit of P. granatum Linn has a high amount of phenolic and flavonoid compounds, which provide beneficial effect for this plant. The oral administration of the fruit extract of P. granatum at doses of 150 and 300 mg/kg bw for 21 days significantly reduced blood glucose level, triglycerides, serum cholesterol, LDL-cholesterol, AST and ALT enzyme. Our results suggested that the fruit extract of P. granatum has strong antidiabetic effect in STZ-induced diabetic mice. The fruit of this plant might be a potential source of drug for treatment of diabetes.

Ginseng for the treatment of diabetes and diabetes-related cardiovascular complications: a discussion of the evidence 1

Diabetes mellitus (DM) is a chronic metabolic disorder associated with elevated blood glucose levels due either to insufficient insulin production (type 1 DM) or to insulin resistance (type 2 DM). The incidence of DM around the world continues to rise dramatically with more than 400 million cases reported today. Among the most serious consequences of chronic DM are cardiovascular complications that can have deleterious effects. Although numerous treatment options are available, including both pharmacological and nonpharmacological, there is substantial emerging interest in the use of traditional medicines for the treatment of this condition and its complications. Among these is ginseng, a medicinal herb that belongs to the genus Panax and has been used for thousands of years as a medicinal agent especially in Asian cultures. There is emerging evidence from both animal and clinical studies that ginseng, ginseng constituents including ginsenosides, and ginseng-containing formulations can produce beneficial effects in terms of normalization of blood glucose levels and attenuation of cardiovascular complications through a multiplicity of mechanisms. Although more research is required, ginseng may offer a useful therapy for the treatment of diabetes as well as its complications.

Polysiphonia japonica Extract Attenuates Palmitate-Induced Toxicity and Enhances Insulin Secretion in Pancreatic Beta-Cells

Beta-cell loss is a major cause of the pathogenesis of diabetes. Elevated levels of free fatty acids may contribute to the loss of β-cells. Using a transgenic zebrafish, we screened ~50 seaweed crude extracts to identify materials that protect β-cells from free fatty acid damage. We found that an extract of the red seaweed Polysiphonia japonica (PJE) had a β-cell protective effect. We examined the protective effect of PJE on palmitate-induced damage in β-cells. PJE was found to preserve cell viability and glucose-induced insulin secretion in a pancreatic β-cell line, Ins-1, treated with palmitate. Additionally, PJE prevented palmitate-induced insulin secretion dysfunction in zebrafish embryos and mouse primary islets and improved insulin secretion in β-cells against palmitate treatment. These findings suggest that PJE protects pancreatic β-cells from palmitate-induced damage. PJE may be a potential therapeutic functional food for diabetes.

Effect of lactating sows' diet supplemented with cactus (Opuntia ficus-indica) on feed intake and reproductive and productive post-weaning performances

The effect of cactus (Opuntia ficus-indica) added to the diet of lactating (21 days of lactation) sows on voluntary feed intake, and its impact on the productive and reproductive post-weaning performance was evaluated. Data collected of 72 farrowings from 37 hybrid sows were analyzed during 12-month period. The sows were divided into two groups: (i) control group (CG; n = 18 sows), sows fed only with commercial feed, and (ii) experimental group (EG; n = 19 sows), sows fed with commercial feed plus cactus supplement. The variables evaluated were blood glucose (BG), daily feed intake (DFI) and total feed intake (TFI), loss of body weight (LBW), weaning-estrus interval (WEI), and subsequent litter size (SLS). Data analysis was carried out using fixed effects models. A nested effect was found for farrowing number (FN) into of group and an interaction group × season on the analyzed variables (P < 0.001). EG observed lower levels of BG with 47.0 ± 7.9 mg dL-1 pre-prandial and 56.1 ± 5.9 mg dL-1 post-prandial at the 10th day of lactation (P < 0.05). DFI and TFI were higher in the sows of the EG independently of the FN and season (P < 0.05). No differeces were observed on the nested effect of FN into group on the levels of BG (P < 0.05). Autumn showed the higher TFI: 121.4 kg-1 sow-1 (P < 0.05). Sows from CG 3rd farrowing and from EG 4th farrowing observed higher LBW (13.8 and 6.9%, respectively) (P < 0.05). Summer showed a higher LBW with 12.7% for CG and 8.2% for EG (P < 0.05). EG showed a lower WEI (5.5 days) and greater SLS up to 1.8 piglets more depending upon the season (P < 0.05). The lactating sow's diet supplemented with cactus can counterbalance the negative effects of lactational hypophagia due to reduction on levels of BG during lactation and an increase on DFI and, therefore, improves performance of LBW, WEI, and SLS.

Diphlorethohydroxycarmalol Attenuates Methylglyoxal-Induced Oxidative Stress and Advanced Glycation End Product Formation in Human Kidney Cells

Diabetic nephropathy is the leading cause of end-stage renal disease in patients with diabetes mellitus. Oxidative stress has been shown to play an important role in pathogeneses of renal damage in diabetic patients. Here, we investigated the protective effect of diphlorethohydroxycarmalol (DPHC), which is a polyphenol isolated from an edible seaweed, Ishige okamurae, on methylglyoxal-induced oxidative stress in HEK cells, a human embryonic kidney cell line. DPHC treatment inhibited methylglyoxal- (MGO-) induced cytotoxicity and ROS production. DPHC activated the Nrf2 transcription factor and increased the mRNA expression of antioxidant and detoxification enzymes, consequently reducing MGO-induced advanced glycation end product formation. In addition, DPHC increased glyoxalase-1 mRNA expression and attenuated MGO-induced advanced glycation end product formation in HEK cells. These results suggest that DPHC possesses a protective activity against MGO-induced cytotoxicity in human kidney cells by preventing oxidative stress and advanced glycation end product formation. Therefore, it could be used as a potential therapeutic agent for the prevention of diabetic nephropathy.

Zanthoxylum armatum DC extracts from fruit, bark and leaf induce hypolipidemic and hypoglycemic effects in mice- in vivo and in vitro study

Background

Zanthoxylum armatum DC is an important medicinal plant of south East Asia, and has been used to treat various ailments in traditional medicine including diabetes. This study investigated the in vitro and in vivo antidiabetic and biochemical effects of extracts of Z. armatum in mice.

Method

The extracts of fruit, bark and leaf from Z. armatum were tested for α-glucosidase inhibition activity. Albino mice of either sex weighing (26–30 g) assigned into groups. Diabetes was induced by IP injection of alloxan monohydrate (150 mg/kg). The extracts (500 mg/kg) and standard (Glibenclamide 10 mg/kg) were administered to mice for 15 days. Serum biochemical parameters were monitored for the period of study.

Results

The leaves and bark extracts showed maximum α-glucosidase inhibition (96.61 ± 2.13 and 93.58 ± 2.31% respectively). The extracts treated and the standard treated groups showed significant decrease in the fasting blood glucose levels compared to diabetic control. The effect was more pronounced in mice treated with leaves extract. In the in vivo studies body weights of diabetic mice treated with Z. armatum extracts and the standard did not reduced to extent as observed in diabetic control and this difference was significant (p < 0.05). There was a significance (p < 0.001) improvement in blood hemoglobin, urea, creatinine, cholesterol, and triglycerides of the extracts treated diabetic mice. The extracts showed hypolipidemic effect by reducing the LDL level. The extracts produced no prominent changes in proteins levels.

Conclusion

It can be concluded that Z. armatum extracts showed excellent antidiabetic potential in vivo and in vitro and could be considered for further appraisal in clinical assessment and drug development.

Opuntia spp.: Characterization and Benefits in Chronic Diseases

Opuntia species have been used for centuries as food resources and in traditional folk medicine for their nutritional properties and their benefit in chronic diseases, particularly diabetes, obesity, cardiovascular diseases, and cancer. These plants are largely distributed in America, Africa, and the Mediterranean basin. Opuntia spp. have great economic potential because they grow in arid and desert areas, and O. ficus-indica, the domesticated O. species, is used as a nutritional and pharmaceutical agent in various dietary and value-added products. Though differences in the phytochemical composition exist between wild and domesticated (O. ficus-indica) Opuntia spp., all Opuntia vegetatives (pear, roots, cladodes, seeds, and juice) exhibit beneficial properties mainly resulting from their high content in antioxidants (flavonoids, ascorbate), pigments (carotenoids, betalains), and phenolic acids. Other phytochemical components (biopeptides, soluble fibers) have been characterized and contribute to the medicinal properties of Opuntia spp. The biological properties of Opuntia spp. have been investigated on cellular and animal models and in clinical trials in humans, allowing characterization and clarification of the protective effect of Opuntia-enriched diets in chronic diseases. This review is an update on the phytochemical composition and biological properties of Opuntia spp. and their potential interest in medicine.

Dual Effect of Curcumin-Zinc Complex in Controlling Diabetes Mellitus in Experimentally Induced Diabetic Rats

Ultrasound-assisted extraction of curcumin from Curcuma longa was performed in an ultrasonic bath at 30°C using ethanol for 40 min. A successful attempt has been made to prepare curcumin-zinc (Zn) complex using a simple chemical procedure. The complex formation and its stoichiometry were characterized using elemental analysis, Fourier transform (FT)-IR and UV spectroscopy which revealed the interaction of Zn(II) ion (M) with curcumin (ligand, L) to proceed via (ML) complex type formation. Oral administration of curcumin-Zn complex at a concentration of 150 mg/kg body weight/rat/d for 45 d in streptozotocin-induced diabetic rats in comparison to curcumin and/or Zn administration exerted a hypoglycemic effect. A significant reduction in blood glucose, glycosylated hemoglobin (Hb)A1c, and lipid profile parameters with an excellent improvement in plasma insulin levels have been attained. Also, the reduced activities of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea, and creatinine in the diabetic rats treated with the complex exhibited the non-toxic nature of the curcumin-Zn complex. Finally, the larger extent of the complex in hyperglycemic improvement in comparison to curcumin and/or Zn supplementation was interpreted by its dual action on glucose and insulin maintenance.

Comparative evaluation of antidiabetic potential of partially purified bioactive fractions from four medicinal plants in alloxan-induced diabetic rats

Background

Syzygiumcumini, Terminaliachebula, Trigonellafoenumgraecum and Salvadora persica are medicinally important plants well known for their pharmacological activities.

Aim

The aim of this study is to compare the antidiabetic potential of partially purified bioactive fractions isolated from four targeted medicinal plants in diabetic rats.

Methods

Alloxan was administered (125 mg/kg, IP) in albino Wistar rats to produce diabetes. The partially purified bioactive fractions, namely S. cumini tannin fraction (ScTF), T. foenumgraecum (Fenugreek) saponin fraction (FgSF), T. chebula flavonoid fraction (TcFF) and S. persica flavonoid fraction (SpFF), were administered to diabetic rats with the dose of 100 mg/kg, per oral (PO) and the effect of the fractions on body weight, liver glycogen and serum glucose were studied up to 15 days.

Results

The results have indicated that diabetic rats treated with fractions showed a statistically significant (P < 0.05) decrease in serum glucose and increase in body weight and liver glycogen. Among ScTF, FgSF, TcFF and SpFF possesse better hypoglycemic activity in all models.

Conclusion

The present investigation reveals that flavonoid isolated from S. persica is useful in the management of diabetes mellitus because of ability to regulate glucose level and reduce related complications.

Effects of aqueous extract of alfalfa on hyperglycemia and dyslipidemia in alloxan-induced diabetic Wistar rats

BACKGROUND

The aim of this study was to investigate the effects of aqueous extract of alfalfa on blood glucose and serum lipids in alloxan-induced diabetic rats.

MATERIALS AND METHODS

Thirty-two adult male Wistar rats weighing 210-250 g were selected and divided randomly into four groups of eight animals each for 21 days as follows: (1) control group, (2) diabetic control group, (3) diabetic group plus aqueous extract of alfalfa (250 mg/l), and (4) diabetic group plus aqueous extract of alfalfa (500 mg/l). Serum concentrations of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), very low-density lipoprotein (VLDL), glucose, and the liver enzymes such as aspartate transaminase (AST) and alanine transaminase (ALT) were measured at the end of period in all studied groups.

RESULTS

Administration of 250 and 500 mg/l aqueous alfalfa extract resulted in a significantly decreased glucose, TC, TG, LDL-C, VLDL, ALT, and AST levels and increased HDL levels as compared with the control group and diabetic control group (p < 0.05). Histological examination showed that the aqueous alfalfa extract caused reconstruction of damaged liver and pancreas.

CONCLUSION

These results suggest that aqueous alfalfa extract revealed significant effects on blood lipids and glucose levels in diabetic rats and might be useful in prevention and treatment of diabetes. However, further studies are needed to determine the exact impacts of those effects.

Controlling type 2 diabetes mellitus with herbal medicines: A triple-blind randomized clinical trial of efficacy and safety

BACKGROUND

The use of alternative medicines is common in patients with diabetes mellitus. The primary aim of the present study was to determine the effects of cinnamon and Caucasian whortleberry (Vaccinium arctostaphylos L.) on blood glucose control, lipid profile and body mass index (BMI) in patients with type 2 diabetes (T2DM).

METHODS

In all, 105 T2DM patients were recruited to the present randomized triple-blinded clinical trial. Patients were randomly divided into three groups and administered either placebo, cinnamon or whortleberry supplements (1 g/day) for 90 days. Fasting blood glucose (FBG), serum insulin, lipid profiles, and HbA1c were measured before and after the study.

RESULTS

There were no significant differences in baseline characteristics among the three groups. After treatment, FBG, 2-h blood postprandial glucose and homeostasis model assessment of insulin resistance (HOMA-IR) scores were significantly reduced in patients in the whortleberry group, but not in the placebo group. After treatment, there was a significant difference in BMI between the cinnamon and control groups (P = 0.02). There were no significant differences in any variables between the cinnamon and whortleberry groups (P>0.05 for all). In addition, there was a significant decrease in all indices of glucose control in all the cinnamon and whortleberry groups (P < 0.05).

CONCLUSIONS

There were no significant differences in blood glucose levels, insulin sensitivity or lipid profile among the three groups. However, the use of cinnamon and whortleberry in addition to conventional medical treatment is recommended to adjust weight and blood glucose levels in patients with T2DM, respectively.

Interaction of Glucagon G-Protein Coupled Receptor with Known Natural Antidiabetic Compounds: Multiscoring In Silico Approach

Glucagon receptor (GCGR) is a secretin-like (class B) family of G-protein coupled receptors (GPCRs) in humans that plays an important role in elevating the glucose concentration in blood and has thus become one of the promising therapeutic targets for treatment of type 2 diabetes mellitus. GCGR based inhibitors for the treatment of type 2 diabetes are either glucagon neutralizers or small molecular antagonists. Management of diabetes without any side effects is still a challenge to the medical system, and the search for a new and effective natural GCGR antagonist is an important area for the treatment of type 2 diabetes. In the present study, a number of natural compounds containing antidiabetic properties were selected from the literature and their binding potential against GCGR was determined using molecular docking and other in silico approaches. Among all selected natural compounds, curcumin was found to be the most effective compound against GCGR followed by amorfrutin 1 and 4-hydroxyderricin. These compounds were rescored to confirm the accuracy of binding using another scoring function (x-score). The final conclusions were drawn based on the results obtained from the GOLD and x-score. Further experiments were conducted to identify the atomic level interactions of selected compounds with GCGR.

Complementary and alternative medicines for diabetes mellitus management in ASEAN countries

AIM

The aim of this study was to explore complementary or alternative practices used to promote health and reduce complications of patients with diabetes mellitus (DM).

DESIGN

This qualitative, interpretative study recruited 30 adults including practitioners (n=15) and DM patients (n=15). The participants reside in the northeast of Thailand and in Vientiane of Lao People's Democratic Republic, and they have undergone treatment with at least a kind of complementary and alternative medicines (CAMs) for the care and management of DM. They were interviewed about their experiences, and the data were analyzed thematically. The study methodology was informed by hermeneutic phenomenology.

RESULT

After several years of ineffective treatments, practitioners looked for an alternative to conventional health care to treat patients on long-term antidiabetic drugs, yet the patients suffered from progressive complications. They sought out health care that would more effectively meet their self-perceived needs in treatment particularly of a chronic disease such as DM. The result suggested that CAMs such as acupuncture, massage, exercise, and herbalism were able to meet their requirement in terms of health-care effectiveness obtained from experiences, additional cheap cost and availability in their community, and in accordance with the culture and lifestyles in the context of the ASEAN (Association of Southeast Asian Nations) community.

CONCLUSION

The study explored and revealed the social perceptions of practitioners and patients using Chinese acupuncture, Thai massage, stretching exercise, and herbalism, as CAMs for DM management. The perceptions attributed to patient-practitioner consensus can hold a key to a more comprehensive health care, as a means to expand the boundaries for contemporary health-care provision. However, more study is needed in the future clinical trial research.

Natural products for the management of type 2 diabetes mellitus and comorbid conditions

OBJECTIVE

To provide pharmacists with practical information to guide consumers in their choices of herbal products and dietary supplements for the management of type 2 diabetes mellitus (T2DM) and its comorbid disease states.

SUMMARY

The herbal and dietary supplement market has grown exponentially over the past decade as Americans increasingly use such agents for generalized health and the prevention and treatment of chronic disease states.1 Pharmacist advice is often requested on the use of these agents for the management of T2DM; however, this is an area that has insufficient evidence to support confident recommendations. Many published studies involving herbal agents and dietary supplements are small and poorly designed, with heterogeneous results. Pharmacists should be aware of the safety and efficacy data available for these agents, recognize potential drug interactions, and identify acceptable manufactured products.

CONCLUSION

The strongest scientific evidence for blood glucose lowering effect is associated with alpha-lipoic acid and fenugreek. There is also good evidence supporting the use of ivy gourd, gymnema, and vitamin E for management of hyperglycemia; however, caution should be used when recommending vitamin E. Pharmacists should advise consumers to disclose use of any of these products to all of their health care providers.

C-4 gem-dimethylated oleanes of Gymnema sylvestre and their pharmacological activities

Gymnema sylvestre R. Br., one of the most important medicinal plants of the Asclepiadaceae family, is a herb distributed throughout the World, predominantly in tropical countries. The plant, widely used for the treatment of diabetes and as a diuretic in Indian proprietary medicines, possesses beneficial digestive, anti-inflammatory, hypoglycemic and anti-helmentic effects. Furthermore, it is believed to be useful in the treatment of dyspepsia, constipation, jaundice, hemorrhoids, cardiopathy, asthma, bronchitis and leucoderma. A literature survey revealed that some other notable pharmacological activities of the plant such as anti-obesity, hypolipidemic, antimicrobial, free radical scavenging and anti-inflammatory properties have been proven too. This paper aims to summarize the chemical and pharmacological reports on a large group of C-4 gem-dimethylated pentacyclic triterpenoids from Gymnema sylvestre.

Curcumin and diabetes: a systematic review

Turmeric (Curcuma longa), a rhizomatous herbaceous perennial plant of the ginger family, has been used for the treatment of diabetes in Ayurvedic and traditional Chinese medicine. The active component of turmeric, curcumin, has caught attention as a potential treatment for diabetes and its complications primarily because it is a relatively safe and inexpensive drug that reduces glycemia and hyperlipidemia in rodent models of diabetes. Here, we review the recent literature on the applications of curcumin for glycemia and diabetes-related liver disorders, adipocyte dysfunction, neuropathy, nephropathy, vascular diseases, pancreatic disorders, and other complications, and we also discuss its antioxidant and anti-inflammatory properties. The applications of additional curcuminoid compounds for diabetes prevention and treatment are also included in this paper. Finally, we mention the approaches that are currently being sought to generate a "super curcumin" through improvement of the bioavailability to bring this promising natural product to the forefront of diabetes therapeutics.

Tes, Licuados, and Capsulas: herbal self-care remedies of Latino/Hispanic immigrants for type 2 diabetes

PURPOSE

The purpose of this cross-sectional, descriptive study was to explore the characteristics of herbal remedy use for diabetes among Latinos/Hispanics with type 2 diabetes.

METHODS

A convenience sample of 75 Latino/Hispanic adults with type 2 diabetes was recruited from community-based settings in North Carolina. Data were collected through face-to-face bilingual interviews. Measures included a demographic questionnaire; the Traditional, Complementary, and Alternative Practices Questionnaire; and biophysical indicators of A1C and body mass index.

RESULTS

Sixty-nine percent of the sample reported using herbal remedies for diabetes self-care. Forty-nine herbal products were identified. The most commonly reported products were prickly pear cactus, aloe vera, celery, and chayote. The perceived effectiveness of products varied; some said they helped "a lot" while others noted the development of side effects. Over three quarters (77%) of persons using herbal remedies reported concurrent use with prescribed medications. Also, some participants reported skipping or altering the dose of diabetes medications when using herbal remedies. Most (77%) reported not disclosing herbal remedy use to health care providers.

CONCLUSIONS

Diabetes educators and other health care providers need to ask Latino/Hispanic clients about their use of herbal remedies and become knowledgeable about herbal products to provide advice about safety.

An evidence-based systematic review of gymnema (Gymnema sylvestre R. Br.) by the Natural Standard Research Collaboration

An evidence-based systematic review of gymnema (Gymnema sylvestre R. Br.), including written and statistical analysis of scientific literature, expert opinion, folkloric precedent, history, pharmacology, kinetics/dynamics, interactions, adverse effects, toxicology, and dosing.

Antidiabetic effects of Corni Fructus extract in streptozotocin-induced diabetic rats

PURPOSE

Diabetes is the leading cause of end-stage renal failure. The present study was undertaken to characterize the effects of Corni Fructus on diabetic nephropathy in streptozotocin-induced diabetic rats and their mechanisms.

MATERIALS AND METHODS

Streptozotocin-diabetic rats were orally administrated with Corni Fructus at a dose of 100, 200 or 400 mg/kg body mass for 40 days.

RESULTS

Corni Fructus-treated diabetic rats showed significant decreases of blood glucose, urinary protein levels and water consumption. Corni Fructus also reduced serum total cholesterol, total triglyceride and low-density lipoprotein cholesterol levels, and showed a tendency of enhancing high-density lipoprotein cholesterol level. Levels of serum albumin and creatinine in diabetic rats were also significantly reduced by Corni Fructus administration at a dose of 200 and 400 mg/kg body mass compared with non-treated diabetic rats. Corni Fructus increased catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidose (GSH-px) activities in the kidneys of diabetic rats. Furthermore, Corni Fructus treatment enhanced renal peroxisome proliferator-activated receptor-γ (PPARγ) expression in diabetic rats.

CONCLUSION

These results demonstrated that Corni Fructus may have the potential to protect the animals from diabetic nephropathy by amelioration of oxidative stress and stimulation of PPARγ expression.

Effect of Opuntia streptacantha Lem. on alpha-glucosidase activity

ETHNOPHARMACOLOGICAL RELEVANCE

In Mexico, Opuntia streptacantha is used as part of a traditional medicine in the treatment of diabetes mellitus. Several studies have reported an anti-hyperglycemic effect from the plant, but none have focused on finding a mechanism of action to explain these results. This paper focuses on one of the most recurrent hypotheses for the effect of O. streptacantha: the mechanism of action is the hydrolysis of disaccharides, either by enzymatically inhibiting the alpha glucosidase inhibitors (AGIs) or mechanically acting as a barrier.

MATERIALS AND METHODS

To test our hypothesis, three different experiments were performed. A maltose tolerance test was carried out using the total extract (TE) and the juice of the plant. Six different extracts were tested in a free-enzyme assay, four of which were aqueous extracts varying according to the procedure of removing the insoluble particles in an attempt to reduce the loss of the water-soluble compounds. The main component of the total extract, a derivative of (4-hydroxy)-phenyl acetic acid, was also tested. For both the maltose tolerance test and the free-enzyme assay, acarbose was used as a control drug. Finally, an everted small intestine assay was also performed.

RESULTS AND CONCLUSIONS

The maltose tolerance test confirmed that an anti-hyperglycemic effect occurs at doses of 100 mg/kg TE and 4 mL/kg juice. No inhibition on AGIs was observed in the free-enzyme assay, and neither a mechanic nor enzymatic effect on disaccharide hydrolysis was observed in the everted intestine assay.

CONCLUSIONS

The anti-hyperglycemic effect of O. streptacantha was confirmed, and the results presented here contribute to the understanding that this effect is not due to the action on alpha-glucosidases or related to the intestinal hydrolysis of disaccharides.

Antiparasitic antioxidant phenylpropanoids and iridoid glycosides from Tecoma mollis

A radical scavenging guided phytochemical study on the stem bark of Tecoma mollis afforded seven active phenylpropanoid glycosides (1-7), including a new one (4), and one iridoid (8). The structures of the isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Compounds (1-7) displayed promising antioxidant activity (DPPH assay) in relation to ascorbic acid (positive control). The antimicrobial activity for compounds (1-8) was evaluated against five bacterial and five fungal strains. The isolated compounds exhibited nonselective weak to moderate antimicrobial activity. The highest antileishmanial activity against Leishmania donovani was observed for compound (7) with an IC₅₀ value of 6.71 μg/ml, using pentamidine and amphotericin B as drug controls. Compound (5) exhibited moderate antimalarial activity (45% inhibition) against chloroquine sensitive (D6) clones of Plasmodium falciparum.

The efficacy and safety study of dietary supplement PURIAM110 on non-insulin taking Korean adults in the stage of pre-diabetes and diabetes mellitus: protocol for a randomized, double-blind, placebo-controlled, and multicenter trial-pilot study

Background

Diabetes has already become a threat to the nation and the individual due to its high prevalence rates and high medical expenses. Therefore, preventing diabetes at an earlier stage is very important. Despite advances in antidiabetic agents, we have not yet achieved any satisfying results in treating diabetes. Among various treatments, medicinal herbs and supplements for diabetes are reported to show generally good efficacy and safety data. In particular, PURIAM110, a compound from orange fruits and mulberry leaves, is supposed to prevent the progress of type II diabetes mellitus and improve diabetic symptoms. This is the first reported pilot study about the protective effect of the orange fruits and mulberry leaves mixture against pre-diabetes on Korean adults. Based on these positive results of herb-derived components, extended studies of dietary supplements have to be done to suggest confirmative evidences.

Methods/Design

The efficacy and safety study of PURIAM110 is a double-blinded, placebo-controlled, randomized, and multi-center clinical trial. A total of 45 subjects will participate in this study for 6 weeks.

Discussion

The present protocol will confirm the efficacy and safety of PURIAM110 for pre-diabetes, suggesting more basic knowledge to conduct further randomized controlled trials (RCT). In addition, PURIAM110 can be an alternative dietary supplemental remedy for diabetes patients.

Trial Registration

ISRCTN: ISRCTN44779824

Anti-hyperglycemic effect of Opuntia streptacantha Lem

AIM OF THE STUDY

This experiment studied two extracts of Opuntia streptacantha, a plant used by the Mexican population to treat type 2 diabetes, in different assays to contribute to the understanding of the hypoglycemic mechanism of this plant.

MATERIALS AND METHODS

Two different extracts were prepared and tested: the first extract was a filtrate of the traditional liquefied extract (LE) preparation of the cladode; and the second filtrate extract (FE) is a filtered sample of the first. Both extracts contained a newly identified compound for Opuntia (4-hydroxy)-phenyl acetic acid derivate, they were tested on streptozotocin (STZ)-diabetic rats in a series of two tests. The first test was performed to confirm if STZ-diabetic rats presented a hypoglycemic effect after administration of the extracts (LE 135 mg/kg and FE 27 mg/kg). In the second experiment, the extracts were administered before an oral glucose tolerance test (OGTT) to confirm if they have an anti-hyperglycemic effect (LE 135 mg/kg, FE 12 and 27 mg/kg).

RESULTS

The extracts administered to STZ-diabetic rats did not produce a significant hypoglycemic effect compared to the control group, while the same extracts administered before an OGTT produced an anti-hyperglycemic effect compared to the control group.

CONCLUSIONS

The filtered, traditional LE of the cladode of Opuntia streptacantha produces an anti-hyperglycemic effect when administered before a glucose challenge, and this anti-hyperglycemic effect is maintained after filtering the extract. Administration of both plants can improve glycemic control by blocking the hepatic glucose output, especially in the fasting state. These data support the traditional use of the plants as "agua de uso", a cold infusion of the plant consumed over the course of a day.