Protective effect of tannins from Ficus racemosa in hypercholesterolemia and diabetes induced vascular tissue damage in rats

Protective Role of Dietary Polyphenols in the Management and Treatment of Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM), a serious metabolic disorder, is a worldwide health problem due to the alarming rise in prevalence and elevated morbidity and mortality. Chronic hyperglycemia, insulin resistance, and ineffective insulin effect and secretion are hallmarks of T2DM, leading to many serious secondary complications. These include, in particular, cardiovascular disorders, diabetic neuropathy, nephropathy and retinopathy, diabetic foot, osteoporosis, liver damage, susceptibility to infections and some cancers. Polyphenols such as flavonoids, phenolic acids, stilbenes, tannins, and lignans constitute an extensive and heterogeneous group of phytochemicals in fresh fruits, vegetables and their products. Various in vitro studies, animal model studies and available clinical trials revealed that flavonoids (e.g., quercetin, kaempferol, rutin, epicatechin, genistein, daidzein, anthocyanins), phenolic acids (e.g., chlorogenic, caffeic, ellagic, gallic acids, curcumin), stilbenes (e.g., resveratrol), tannins (e.g., procyanidin B2, seaweed phlorotannins), lignans (e.g., pinoresinol) have the ability to lower hyperglycemia, enhance insulin sensitivity and improve insulin secretion, scavenge reactive oxygen species, reduce chronic inflammation, modulate gut microbiota, and alleviate secondary complications of T2DM. The interaction between polyphenols and conventional antidiabetic drugs offers a promising strategy in the management and treatment of T2DM, especially in advanced disease stages. Synergistic effects of polyphenols with antidiabetic drugs have been documented, but also antagonistic interactions that may impair drug efficacy. Therefore, additional research is required to clarify mutual interactions in order to use the knowledge in clinical applications. Nevertheless, dietary polyphenols can be successfully applied as part of supportive treatment for T2DM, as they reduce both obvious clinical symptoms and secondary complications.

A review of Ficus L. genus (Moraceae): a source of bioactive compounds for health and disease. Part 1

The Ficus L. genus, belonging to the Moraceae family, includes around 850 species that are widely distributed in tropical and subtropical regions around the world; including the Eastern Mediterranean, Asia, Africa, Australia, and a large territory of America. Among the most important species are F. deltoidea, F. exasperata, F. sycomorus, F. religiosa, F. microcarpa, F. hirta Vahl, F. benghalensis, F. racemosa, F. elástica, and F. carica. Different parts of Ficus plants (root, stem bark, latex, leaves, pulp and fruits) contain bioactive compounds [flavonoids (flavanols, flavones, flavonols, isoflavones, chalcones, anthocyanins), phenolic acids (hidroxylcinnamic acids, hidroxylbenzoic acids), phytosterols, terpenes (triterpenes, tetraterpenes, diterpenes, sesquiterpenes, monoterpenes), coumarins, hydroxybenzoates, phenylpropanoids, chlorins, pheophytins, megastigmanes, chitinases, organic acids, fatty acids, amino acids, alkaloids, glycosides] which together, are currently useful to more than 30 traditional ethnomedical uses. The present manuscript is the result of scientific search processed with the main electronic databases (PubMEd, SciELO, Latindex, Redalyc, BiologyBrowser, ScienceResearch, ScienceDirect, Academic Journals, Ethnobotany, and Scopus). This first review (Part 1), compiles information from published research (in vitro, in vivo and clinical studies) on its antimicrobial, antifungal, antiviral, anti-helminthic, hypoglycemic, hypolipidemic, hepatoprotective, anti-inflammatory, analgesic, and antipyretic properties; as well as its possible adverse and/or toxicological effects. Given the amount of evidence described in this review it aims to trigger a more detailed scientific research on the important pharmacological properties of all angiosperm plants of the genus Ficus L.

Anti-diabetic Effects of Two Species of Eryngium on Streptozotocin-induced Diabetic Mice

Background: Eryngium is a genus with 274 species, which belongs to the Umbelliferae family. The nine species of this genus are endemic to Iran. The existence of terpenoids, saponins, flavonoids, and steroid components in most Eryngium species is the reason behind their anti-inflammatory, anti-cancer, and, especially, anti-diabetic effects among the well-known medicinal plants. Objectives: This study aimed to evaluate the effects of anti-diabetic features of Eryngium thyrsoideum and caucasicum on streptozotocin (STZ)-induced diabetic mice. Methods: The extract of the plants’ dried samples was prepared by using 70% ethanol solvent and adopting the maceration method. The mice were divided into eight groups, and the mice with a high blood glucose of more than 200 mg/dL were assigned to diabetic groups. Diabetic animals received different doses of the extract orally or through intraperitoneal (IP) injection for eighteen days. The animals were anesthetized by IP injection of ketamine and xylazine, and serum samples were isolated. Results: The results showed that hydroalcoholic extract of E. thyrsoideum significantly reduced the blood sugar level in diabetic groups receiving the extract (oral and IP) in low (100 mg/kg) and high (300 mg/kg) doses. Overall, oral glucose tolerance decreased significantly after two hours. Coincidental management of STZ and 300 mg/kg of the extract consumed orally reduced the blood sugar level remarkably. Serum malondialdehyde (MDA) and serum insulin levels significantly decreased and increased, respectively, in the diabetic groups receiving low and high doses (oral and IP) of the E. thyrsoideum extract. Conclusions: In sum, receiving 100 mg/kg and 300 mg/kg of hydroalcoholic extract (oral and IP) decreased the blood sugar level, while receiving oral glucose tolerance, serum MDA, and serum insulin caused a significant increase.

Bioactive Compounds in Ficus Fruits, Their Bioactivities, and Associated Health Benefits: A Review

Bioactive compounds are secondary metabolites synthesized by plants for maintaining homeostasis; however, they also modulate metabolic processes and demonstrate valuable effects in the human body. The fig was cherished as food and for its pharmaceutical properties. The presence of a wide range of biologically active compounds such as carotenoids, flavonoids, phenols, and vitamin C is obligated for their functional properties as well as their technological capability as a dietary supplement is responsible for most health impacts. Owing to the rich and diversified composition of biologically active compounds these compounds possess different biological properties such as antioxidant, anti-inflammatory, antidiabetic, antimicrobial, and hepatoprotective activity that implies those bioactive substances might be used in the creation of novel culinary and medicinal products. Fig fruit should be widely recognized as a natural functional product. This systematic and comprehensive review gives the notion of developing figs species as a viable and innovative component for its varied food and nonfood applications as a remarkable and primitive source of medication and nourishment.

Pharmaceutical Drugs and Natural Therapeutic Products for the Treatment of Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is the most widespread form of diabetes, characterized by chronic hyperglycaemia, insulin resistance, and inefficient insulin secretion and action. Primary care in T2DM is pharmacological, using drugs of several groups that include insulin sensitisers (e.g., biguanides, thiazolidinediones), insulin secretagogues (e.g., sulphonylureas, meglinides), alpha-glucosidase inhibitors, and the newest incretin-based therapies and sodium-glucose co-transporter 2 inhibitors. However, their long-term application can cause many harmful side effects, emphasising the importance of the using natural therapeutic products. Natural health substances including non-flavonoid polyphenols (e.g., resveratrol, curcumin, tannins, and lignans), flavonoids (e.g., anthocyanins, epigallocatechin gallate, quercetin, naringin, rutin, and kaempferol), plant fruits, vegetables and other products (e.g., garlic, green tea, blackcurrant, rowanberry, bilberry, strawberry, cornelian cherry, olive oil, sesame oil, and carrot) may be a safer alternative to primary pharmacological therapy. They are recommended as food supplements to prevent and/or ameliorate T2DM-related complications. In the advanced stage of T2DM, the combination therapy of synthetic agents and natural compounds with synergistic interactions makes the treatment more efficient. In this review, both pharmaceutical drugs and selected natural products, as well as combination therapies, are characterized. Mechanisms of their action and possible negative side effects are also provided.

Medicinal Plants and Bioactive Compounds for Diabetes Management: Important Advances in Drug Discovery

BACKGROUND

Diabetes is a major public health problem in the world. It affects each and every part of the human body and also leads to organ failure. Hence, great progress is made in the field of herbal medicine and diabetic research.

OBJECTIVES

Our review will focus on the effect of bioactive compounds of medicinal plants which are used to treat diabetes in India and other countries.

METHODS

Information regarding diabetes, oxidative stress, medicinal plants and bioactive compounds was collected from different search engines like Science direct, Springer, Wiley online library, Taylor and francis, Bentham Science, Pubmed and Google scholar. Data was analyzed and summarized in the review.

RESULTS

Anti-diabetic drugs that are in use have many side effects on vital organs like heart, liver, kidney and brain. There is an urgent need for alternative medicine to treat diabetes and their disorders. In India and other countries, herbal medicine was used to treat diabetes. Many herbal plants have antidiabetic effects. The plants like ginger, phyllanthus, gymnea, aswagandha, aloe, hibiscus and curcuma showed significant anti-hyperglycemic activities in experimental models and humans. The bioactive compounds like Allicin, azadirachtin, cajanin, curcumin, querceitin, gingerol possess anti-diabetic, antioxidant and other pharmacological properties. This review focuses on the role of bioactive compounds of medicinal plants in the prevention and management of diabetes.

CONCLUSION

Moreover, our review suggests that bioactive compounds have the therapeutic potential against diabetes. However, further in vitro and in vivo studies are needed to validate these findings.

Terminalia catappa Fruit Extract Reverses Streptozotocin-Induced Diabetic Retinopathy in Rats

OBJECTIVE AND BACKGROUND

Diabetic retinopathy is amongst the most common microvascular complications associated with diabetes. Controlling blood glucose level alone cannot manage diabetes associated complications. Thus, mechanisms that additionally prevent diabetes associated complications are the need of the hour, driving the researchers towards herbal therapies. Terminalia catappa is renowned for its anti-inflammatory, antioxidant, anti-hyperglycemic and anti-angiogenic activity. The current study explores the effect of Terminalia catappa fruit extract on streptozotocin-induced diabetic retinopathy in rats.

METHODS

Streptozotocin-induced chronic diabetic rat model was utilized in the study. The hydroalcoholic fruit extract of T. catappa in 20mg/kg, 30mg/kg and 40mg/kg dose and standard anti-diabetic drug, glibenclamide (10mg/kg) was given orally. Retinopathy was evaluated by monitoring lenticular, fundus images and measuring arteriole and venule tortuosity index. Oxidative, angiogenic and inflammatory biomarkers were assessed at the 12th week in the retinal homogenate. Histopathological changes in the retina were also examined. Data was analyzed using one-way Repeated Measure ANOVA followed by the Mann-Whitney test.

RESULTS

The hydro-alcoholic fruit extract of T. catappa significantly decreased blood glucose (p<0.001) in a dose-dependent manner in diabetic rats. Cataract lens was observed in all experimental groups and became clear (grade 0) with 40mg/kg and with 40mg/kg along with glibenclamide at the eighth and sixth week, respectively. The hydro-alcoholic fruit extract in all three doses significantly reduced (p<0.01) arteriole and venule tortuosity in diabetic rats. T. catappa in all three doses in diabetic rats showed a modulatory effect in oxidative, angiogenic and inflammatory biomarkers.

CONCLUSION

T. catappa reverses diabetes-induced retinopathy by anti-hyperglycemic, anti-oxidant, anti-angiogenic and anti-inflammatory actions, and thus has a potential to be used in diabetes-induced retinopathy.

Tannins and vascular complications of Diabetes: An update

BACKGROUND

Diabetes mellitus is a chronic metabolic disorder associated with persistent increased level of glucose in the blood. According to a report by World Health Organisation (WHO), prevalence of diabetes among adults over 18 years of age had reached to 8.5% in year 2014 which was 4.7% in 1980s. The Prolong increased level of glucose in blood leads to development of microvascular (blindness, nephropathy and neuropathy) and macrovascular (cardiovascular and stroke) degenerative complications because of uncontrolled level of glucose in blood. This also leads to the progression of oxidative stress and affecting metabolic, genetic and haemodynamic system by activation of polyol pathway, protein kinase C pathway, hexosamine pathway and increases advanced glycation end products (AGEs) formation. Diabetes mellitus and its associated complications are one of the major leading causes of mortality worldwide. Various natural products like alkaloids, glycosides, flavonoids, terpenoids and polyphenols are reported for their activity in management of diabetes and its associated diabetic complications. Tannins are systematically studied by many researchers in past few decades for their effect in diabetes and its complications.

AIM

The present review was designed to compile the data of tannins and their beneficial effects in the management of diabetic complications.

METHOD

Literature search was performed using various dataset like pubmed, EBSCO, proQuest Scopus and selected websites including the National Institutes of Health (NIH) and the World Health Organization (WHO).

RESULTS

Globally, more than 400 natural products have been investigated in diabetes and its complications. Tannins are the polyphenolic compounds present in many medicinal plants and various dietary sources like fruits, nuts, grains, spices and beverages. Various reports have shown that compounds like gallic acid, ellagic acid, catechin, epicatechin and procynidins from medicinal plants play major role in controlling progression of diabetes and its related complications by acting on molecular pathways and key targets involved in progression. Many chemists used above mentioned phyto-constituents as a pharmacophore for the developing new chemical entities having higher therapeutic benefits in management of diabetic complications.

CONCLUSION

This review focuses on the role of various tannins in prevention and management of diabetic complications like diabetic nephropathy, diabetic neuropathy, diabetic retinopathy and diabetic cardiomyopathy. It will help researchers to find some leads for the development of new cost effective therapy using dietary source for the management of diabetic complications.

The genus Ficus (Moraceae) used in diet: Its plant diversity, distribution, traditional uses and ethnopharmacological importance

ETHNOPHARMACOLOGICAL RELEVANCE

A new field of enthnopharmacology has opened, where pharmacological studies draw their attention from the conventional only-medicine approach towards the dietary dimension. The uses of Ficus species in the human diet have been extensively documented by ethnobotanical field surveyors. Overlap commonly exist between the dietary and medicinal selection of Ficus species but not for choices of the plant parts and development stages, which leave a large space for ethnopharmacological study.

AIMS OF THE STUDY

1) To review published works on the dietary uses of Ficus species and their food-medicine overlap based on traditional uses, and 2) to spark interest in ethnopharmacological studies on the dietary uses of Ficus species.

MATERIALS AND METHODS

Data was collected and analyzed from many sources, including published and unpublished ethnobotanical field surveys, taxonomic and distribution information, international journals, books, thesis, floras, reports and professional databases. The possible biases arising from data sources are assessed to make sure that the dataset are global representative.

RESULTS

A total of 132 Ficus species are reported for dietary uses, including one subspecies and four varieties. Those species are found across all of the six subgenera of the genus Ficus. For distribution, 98 species from the Indo-Australasian region, 27 species from the African tropics (with one species, F. palmata, from both the two regions) and 8 from the Neotropics. The parts most commonly used are the figs (i.e. syconium or fruits) (110 species) and leaves (67 species), in various growth stages. It is also found that the certain plant parts of 78 species are used both for dietary and medicinal purpose. Among which the figs are frequently cited in the treatment of diarrhea and oligogalactia, the leaves in the treatment of diarrhea, stomach complaintsas, antidote and diabetes, the latex in the treatment of intestinal worms and wounds, and the barks in the treatment of diarrhea.

CONCLUSIONS

We demonstrate that throughout its area of distribution, the genus Ficus is generally used as a dietary plant, although use of a individual species seems uncommon. Furthermore, we highlight the diet-medicine overlap of the uses of this genus, which should enable further understanding of the potential for broader health benefits, rather than limiting studies in this genus to its only-medicinal properties.

Phytochemical characterization of polyphenolic compounds with HPLC-DAD-ESI-MS and evaluation of lipid-lowering capacity of aqueous extracts from Saharan plant Anabasis aretioides (Coss & Moq.) in normal and streptozotocin-induced diabetic rats

OBJECTIVE

Anabasis aretioides (Coss & Moq.), a Saharan plant belonging to Chenopodiaceae family, is widely distributed in semi-desert areas from the Tafilalet region of Morocco. This plant is extensively used by local population against diabetes and cardiovascular disorders. The purpose of the study was to investigate the effect of the aqueous A. aretioides extract on lipid metabolism in normal and streptozotocin (STZ)-induced diabetic rats and to identify the polyphenolic compounds present. In addition, the in vitro antioxidant activity of the aqueous A. aretioides extract was also evaluated.

METHODS

The effect of an aerial part aqueous extract (APAE) of A. aretioides (5 mg/kg of lyophilized A. aretioides APAE) on plasma lipid profile was investigated in normal and STZ-induced diabetic rats (n = 6) after once daily oral administration for 15 days. The aqueous extract was tested for its 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity. Polyphenolic compounds in the extracts were definitively characterized by high-performance liquid chromatography-diode array detection-electrospray ionization-mass spectrometry.

RESULTS

In diabetic rats, oral administration of A. aretioides APAE provoked a significant decrease in both plasma cholesterol and triglyceride levels from the first to the second week (P < 0.01). A significant decrease on plasma triglyceride levels was also observed in normal rats (P < 0.01), where the reduction was 53%. In addition, the phytochemical analysis revealed the presence of 12 polyphenolic compounds. Moreover, according to the DPPH radical-scavenging activity, the aqueous extract showed an in vitro antioxidant activity.

CONCLUSION

Aqueous A. aretioides APAE exhibits lipid-lowering and in vitro antioxidant activities. Many polyphenols were present in this extract and these phytoconstituents may be involved in the pharmacological activity of this plant.

A role of Ficus species in the management of diabetes mellitus: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetes mellitus is one of the most common global health concerns, with a rapidly increasing incidence. A variety of medicinal plants, particularly those belonging to the genus Ficus (Moraceae), and their active compounds have been used to treat diabetes and related chronic disorders since ancient times.

AIM OF THE STUDY

The aim of this review is to provide information regarding traditional and scientific knowledge of Ficus species with antidiabetic activity to researchers.

MATERIALS AND METHODS

A literature search was conducted to obtain information about the antidiabetic properties of Ficus from the electronic databases. Common and scientific names of various Ficus species were used as keywords for the search, along with the terms antidiabetic, hypoglycemic and diabetes.

RESULTS

Among the assorted species of Ficus that were included in our search, F. benghalensis, F. carica, F. glomerata, F. glumosa, F. racemosa, and F. religiosa exhibited remarkable antidiabetic properties with various mechanisms of action. Moreover, Ficus species are versatile sources of bioactive metabolites such as flavonoids, phenolic acids, tannins, alkaloids, glycosides, coumarins, triterpenoids, sterols and vitamin E. These extracts and isolated compounds significantly have enhanced insulin secretion and subsequently reduced blood glucose level in various in vivo studies.

CONCLUSION

This review summarizes the antidiabetic potentials of the genus Ficus, including pharmacological studies with mechanisms of action as well as ethnobotanical uses. This review can help inform future scientific research towards the development of novel antidiabetic drugs.

Effect of Diabetea tea ™ consumption on inflammatory cytokines and metabolic biomarkers in type 2 diabetes patients

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetea tea™ (DT) is an anti-diabetic alternative medicine in some Asian countries. The main constituent of DT is black tea originating from Camellia sinensis that is supplemented by 12 other medicinal plants. Black tea contains a large amount of the flavonoids catechins especially epigallocatechin gallate (EGCG) which has anti-inflammatory and antioxidative capacity. This study was undertaken to evaluate the possible effects of DT intake on inflammatory cytokines, regulatory T cells (Tregs) and metabolic biomarkers in T2DM.

MATERIALS AND METHODS

The study included 50 patients with T2DM. The patients had received 3 cups (600ml) of DT extract or placebo (PL) extract per day during a period of 12 weeks. Intracellular cytokine expression in peripheral blood mononuclear cell (PBMC) as well as the glycemic and lipid profiles were measured at baseline and after the treatment period. The active constituents of the medicinal plants included in DT were investigated by gas chromatography-mass spectrometry (GC/MS).

RESULTS

Ingestion of DT suppressed CD4+ T cell expression of IL-1β and Il-8 (p<0.05) and up-regulated the expression of IL-10 and the Treg/IL-17 ratio (p<0.05) which was not shown in PL. A significant decrease in HbA1c and LDL was observed at the end of the study period (p<0.05) in DT. The GC/MS analyses of DT indicated the presence of lupeol, β-Amyrin and β-sitosterol. Also analyses of individual herbs showed the presence of higher levels of lupeol and β-Amyrin in Nuga Ficus bengalensis and β-sitosterol in the Attikka Ficus racemosa, indicating that the active ingredients of DT are concentrated in these two herbs.

CONCLUSION

The present study provides evidence that DT has hypoglycemic and antihyperlipidemic properties. Interestingly, DT has anti-inflammatory effects. These properties are attributed to the flavonoids, triterpenes and phytosterol contents of the tea. We suggest that DT protects against diabetes complications in the long term.

Antihyperglycemic Effect of Methanol Extract of Syzygium polyanthum (Wight.) Leaf in Streptozotocin-Induced Diabetic Rats

Syzygium polyanthum (S. polyanthum), a plant belonging to Myrtaceae, is widely used in Indonesian and Malaysian cuisines. Diabetic patients in Indonesia also commonly use it as a traditional medicine. Hence, this study was conducted to investigate the antihyperglycemic effect of the methanol extract (ME) of S. polyanthum leaf and its possible mechanisms of action. To test for hypoglycemic activity, ME was administered orally to normal male Sprague Dawley rats after a 12-h fast. To further test for antihyperglycemic activity, the same treatment was administered to glucose-loaded (intraperitoneal glucose tolerance test, IPGTT) and streptozotocin (STZ)-induced diabetic rats, respectively. Hypoglycemic test in normal rats did not show significant reduction in blood glucose levels (BGLs) by the extract. Furthermore, IPGTT conducted on glucose-loaded normal rats also did not show significant reduction of BGLs. However, repeated administration of metformin and three doses of ME (250, 500 and 1000 mg/kg) for six days caused significant reduction of fasting BGLs in STZ-induced diabetic rats. The possible mechanisms of action of S. polyanthum antihyperglycemic activity were assessed by measurement of intestinal glucose absorption and glucose uptake by isolated rat abdominal muscle. It was found that the extract not only inhibited glucose absorption from the intestine but also significantly increased glucose uptake in muscle tissue. A preliminary phytochemical qualitative analysis of ME indicated the presence of tannins, glycosides, flavonoids, alkaloids and saponins. Additionally, Gas Chromatography-Mass Spectrometry (GC-MS) analysis detected squalene. In conclusion, S. polyanthum methanol leaf extract exerts its antihyperglycemic effect possibly by inhibiting glucose absorption from the intestine and promoting glucose uptake by the muscles.

Blood glucose level and lipid profile of alloxan-induced hyperglycemic rats treated with single and combinatorial herbal formulations

The current study sought to investigate the capacities of single and combinatorial herbal formulations of leaf extracts of Acanthus montanus, Asystasia gangetica, Emilia coccinea, and Hibiscus rosasinensis to reverse hyperglycemia and dyslipidemia in alloxan-induced diabetic male rats. Phytochemical composition of the herbal extracts, fasting plasma glucose concentration (FPGC), and serum lipid profile (SLP) of the rats were measured by standard methods. The relative abundance of phytochemicals in the four experimental leaf extracts was in the following order: flavonoids > alkaloids > saponins > tannins. Hyperglycemic rats (HyGR) treated with single and combinatorial herbal formulations showed evidence of reduced FPGC compared with the untreated HyGR and were normoglycemic (FPGC < 110.0 mg/dL). Similarly, HyGR treated with single and combinatorial herbal formulations showed evidence of readjustments in their SLPs. Generally, HyGR treated with triple herbal formulations (THfs) exhibited the highest atherogenic index compared with HyGR treated with single herbal formulations (SHfs), double herbal formulations (DHfs), and quadruple herbal formulation (QHf). The display of synergy or antagonism by the composite herbal extracts in ameliorating hyperglycemia and dyslipidemia depended on the type and number of individual herbal extract used in constituting the experimental herbal formulations. Furthermore, the capacities of the herbal formulations (SHfs, DHfs, THfs, and QHf) to exert glycemic control and reverse dyslipidemia did not follow predictable patterns in the animal models.

The biochemical and histological effects of lichens in normal and diabetic rats

Oxidative stress plays an important role in causing diabetes; however, no studies have thoroughly reported on the toxic and beneficial effects of lichen extracts in patients with diabetes mellitus (DM). This study covers a previously unrecognized effect of two well-known lichen species Cetraria islandica and Pseudevernia furfuracae in streptozotocin (STZ)-induced diabetes. In experimental design, control or diabetic rats were either untreated or treated with aqueous lichen extracts (250–500 mg/kg /day) for 2 weeks starting at 72 h after STZ injection. On day 14, animals were anaesthetized, and metabolic and biochemical parameters were appreciated between control and treatment groups. The histopathology of liver was examined using three different staining methods: hematoxylin–eosin (H&E), periodic acid Schiff (PAS), and reticulin and Sudan Black B. Our experimental data showed that increasing doses of C. islandica and P. furfuracae alone did not have any detrimental effects on studied parameters and the malondialdehyde level of liver. C. islandica extract showed positive results for antioxidant capacity compared to doses of P. furfuracae extract. However, the protective effect of C. islandica extract on diabetes-induced disorders and hepatic damages is still unclear. Moreover, unfortunately, animals subjected to DM therapy did not benefit from the usage of increasing lichen doses due to their unchanged antioxidant activity in tissues. The results obtained in present study suggested that C. islandica and P. furfuracae is safe but the power of these is limited because of intensive oxidative stress in liver of type 1 diabetic rats. It is also implied that C. islandica extract is especially suitable for different administration routes in DM animals.

The effects of Cetraria islandica and Pseudevernia furfuracea extracts in normal and diabetic rats

Lichens are symbiotic organisms composed of a fungus joined to a photosynthesizing partner that can be either an alga or a cyanobacterium. They can be used as a novel bioresource for natural antioxidants. However, there is also a need for further studies to validate the lichens used in medicinal remedies. This study covers a previously unrecognized effects of Cetraria islandica (CIAE) and Pseudevernia furfuracea (PFAE) in streptozotocin (STZ)-induced diabetes. In experimental design, control or diabetic rats were either untreated or treated with aqueous lichen extracts (250–500 mg/kg/day) for 2 weeks starting at 72 h after STZ injection. On day 14, animals were anesthetized, metabolic and biochemical parameters were appreciated between control and treatment groups. The histopathology of kidney was examined using four different staining methods: hematoxylin–eosin (H&E), periodic acid-Schiff (PAS), Masson trichrome and Congo red. Our experimental data showed that increasing doses of CIAE and PFAE did not have any detrimental effects on the studied parameters and the malondialdehyde level of kidney. CIAE extract showed prominent results compared to doses of PFAE extract for antioxidant capacity. However, the protective effect of CIAE extract was inadequate on diabetes-induced disorders and kidney damages. Moreover, animals subjected to diabetes mellitus (DM) therapy did not benefit unfortunately from the usage of increasing lichen doses due to their unchanged antioxidant activity to tissue. The results obtained in present study suggested that CIAE and PFAE are safe but the power of these is limited because of the intensive oxidative stress in kidney of type 1 diabetic rats. It is also implied that CIAE extract is especially suitable for different administration routes in DM.

Traditional medicinal plants used for the treatment of diabetes in rural and urban areas of Dhaka, Bangladesh--an ethnobotanical survey

BACKGROUND

The usage of medicinal plants is traditionally rooted in Bangladesh and still an essential part of public healthcare. Recently, a dramatically increasing prevalence brought diabetes mellitus and its therapy to the focus of public health interests in Bangladesh. We conducted an ethnobotanical survey to identify the traditional medicinal plants being used to treat diabetes in Bangladesh and to critically assess their anti-diabetic potentials with focus on evidence-based criteria.

METHODS

In an ethnobotanical survey in defined rural and urban areas 63 randomly chosen individuals (health professionals, diabetic patients), identified to use traditional medicinal plants to treat diabetes, were interviewed in a structured manner about their administration or use of plants for treating diabetes.

RESULTS

In total 37 medicinal plants belonging to 25 families were reported as being used for the treatment of diabetes in Bangladesh. The most frequently mentioned plants were Coccinia indica, Azadirachta indica, Trigonella foenum-graecum, Syzygium cumini, Terminalia chebula, Ficus racemosa, Momordica charantia, Swietenia mahagoni.

CONCLUSION

Traditional medicinal plants are commonly used in Bangladesh to treat diabetes. The available data regarding the anti-diabetic activity of the detected plants is not sufficient to adequately evaluate or recommend their use. Clinical intervention studies are required to provide evidence for a safe and effective use of the identified plants in the treatment of diabetes.