Evaluation of the effects of 80% methanolic leaf extract of Caylusea abyssinica (fresen.) fisch. & Mey. on glucose handling in normal, glucose loaded and diabetic rodents

Diabetes mellitus and risk of incident dementia in APOE ɛ4 carriers: an updated meta-analysis

BACKGROUND AND AIM

Diabetes raises the risk of dementia, mortality, and cognitive decline in the elderly, potentially because of hereditary variables such as APOE. In this study, we aim to evaluate Diabetes mellitus and the risk of incident dementia in APOE ɛ4 carriers.

METHOD

We thoroughly searched PubMed (Medline), Scopus, and Google Scholar databases for related articles up to September 2023. The titles, abstracts, and full texts of articles were reviewed; data were extracted and analyzed.

RESULT

This meta-analysis included nine cohorts and seven cross-sectional articles with a total of 42,390 population. The study found that APOE ɛ4 carriers with type 2 diabetes (T2D) had a 48% higher risk of developing dementia compared to non-diabetic carriers (Hazard Ratio;1.48, 95%CI1.36-1.60). The frequency of dementia was 3 in 10 people (frequency: 0.3; 95%CI (0.15-0.48). No significant heterogeneity was observed. Egger's test, which we performed, revealed no indication of publication bias among the included articles (p = 0.2).

CONCLUSION

Overall, diabetes increases the risk of dementia, but further large-scale studies are still required to support the results of current research.

In vitro and in vivo antitrypanosomal activity of the fresh leaves of Ranunculus Multifidus Forsk and its major compound anemonin against Trypanosoma congolense field isolate

BACKGROUND

Animal trypanosomiasis is a major livestock problem due to its socioeconomic impacts in tropical countries. Currently used trypanocides are toxic, expensive, and the parasites have developed resistance to the existing drugs, which calls for an urgent need of new effective and safe chemotherapeutic agents from alternative sources such as medicinal plants. In Ethiopian traditional medicine fresh leaves of Ranunculus multifidus Forsk, are used for the treatment of animal trypanosomiasis. The present study aimed to evaluate the antitrypanosomal activity of the fresh leaves of R. multifidus and its major compound anemonin against Trypanosoma congolense field isolate.

METHODS

Fresh leaves of R. multifidus were extracted by maceration with 80% methanol and hydro-distillation to obtain the corresponding extracts. Anemonin was isolated from the hydro-distilled extract by preparative TLC. For the in vitro assay, 0.1, 0.4, 2 and 4 mg/ml of the test substances were incubated with parasites and cessation or drop in motility of the parasites was monitored for a total duration of 1 h. In the in vivo assay, the test substances were administered intraperitoneally daily for 7 days to mice infected with Trypanosoma congolense. Diminazene aceturate and 1% dimethylsulfoxide (DMSO) were used as positive and negative controls, respectively.

RESULTS

Both extracts showed antitrypanosomal activity although the hydro-distilled extract demonstrated superior activity compared to the hydroalcoholic extract. At a concentration of 4 mg/ml, the hydro-distilled extract drastically reduced motility of trypanosomes within 20 min. Similarly, anemonin at the same concentration completely immobilized trypanosomes within 5 min of incubation, while diminazene aceturate (28.00 mg/kg/day) immobilized the parasites within 10 min. In the in vivo antitrypanosomal assay, anemonin eliminates parasites at all the tested doses (8.75, 17.00 and 35.00 mg/kg/day) and prevented relapse, while in diminazene aceturate-treated mice the parasites reappeared on days 12 to 14.

CONCLUSIONS

The current study demonstrated that the fresh leaves of R. multifidus possess genuine antitrypanosomal activity supporting the use of the plant for the treatment of animal trypanosomiasis in traditional medicine. Furthermore, anemonin appears to be responsible for the activity suggesting its potential as a scaffold for the development of safe and cost effective antitrypanosomal agent.

Validation of Blood Glucose and Lipid-Lowering Effect of Solvent Fractions of the Crinum Abyssinicum Shoot Tips in Streptozotocin-Induced Diabetic Mice

Background

Diabetes mellitus prevalence has reached epidemic levels despite the existence of contemporary treatments. People thus started looking at the possible therapeutic value of natural therapies. Crushed shoot tips of Crinum abyssinicum (Amaryllidaceae) are mixed with water in Ethiopia to treat diabetes, yet this practice is not well supported by science.

Objective

In this experiment, mice models were used to verify the blood sugar and lipid-lowering benefits of solvent fractions of C. abyssinicum shoot tips.

Materials and Methods

In a single-dose treated Streptozotocin (STZ)-induced diabetic model, mice were randomly grouped into eleven categories which include diabetic negative control, diabetic positive control, and 9 diabetic treatment groups. In repeated daily doses treated STZ-induced model, Mice were divided into 6 groups which included normal and diabetic negative control (TW80), diabetic positive control (5 mg/kg glibenclamide), and three diabetic treatment groups 100, 200, and 400 mg/kg). Finally, blood glucose, lipid level, and body weight were examined.

Results

In the single-dose treated diabetic model, there was a significant blood glucose reduction at 200 and 400 mg/kg doses of aqueous fraction and glibenclamide starting from the sixth-hour post-administration unlike ethyl acetate and chloroform fraction compared to baseline and negative control. In repeated daily dose-treated diabetic mice, all three doses (100, 200, and 400 mg/kg of aqueous fraction) resulted in a substantial reduction (P < .001) in blood glucose compared to baseline and negative control on the seventh day and 14th day. Besides the AQF shows improvement in lipid levels and body weight parameters.

Conclusion

The results of the study demonstrated that C. abyssinicum shoot tip fractions have the greatest potential to lower blood sugar and lipid levels, supporting conventional claims for the treatment of diabetes.

Antidiabetic Activities of 80% Methanol Extract and Solvent Fractions of Verbascum Sinaiticum Benth (Scrophulariaceae) Leaves in Mice

Background

Because of the scarcity, high cost, and severe side effects of current medications, it is necessary to discover novel, safe, and affordable anti-diabetic drugs. The current study was conducted to evaluate the antidiabetic activities of Verbascum sinaiticum Benth leaves in mice.

Methods

Leaf coarse powder was extracted with 80% methanol and then fractionated with n-hexane, ethyl acetate, and distilled water. The glucose-lowering effects of V. sinaiticum at 100, 200, and 400mg/kg were then studied. Glibenclamide was used as a positive control at a dose of 5 mg/kg. For oral glucose tolerance tests and hypoglycemia tests, Tween 2% was used as a negative control, while citrate buffer was used as a negative control for antihyperglycemic investigations. The results from the study were evaluated using one-way ANOVA, and then Tukey's post hoc multiple comparison test was performed.

Results

Blood glucose levels were significantly reduced by the V. sinaiticum 80% methanol extract at 400 mg/kg (p<0.05). The blood glucose levels were significantly lowered by the aqueous residue at 400 mg/kg (p<0.05) and the ethyl acetate fractions at 200 mg/kg (p<0.01) and 400 mg/kg (p<0.001); however, none of the fraction extracts resulted in hypoglycemic shock in healthy mice. Higher glucose tolerance was seen in orally glucose-loaded mice after exposure to 80% methanol extracts at 200 and 400 mg/kg (p<0.05), the aqueous residual fraction at 200 mg/kg (p<0.01), and the ethyl acetate fraction at 200 and 400 mg/kg (p<0.05). The ethyl acetate fraction at 200 and 400 mg/kg (p<0.01), the 80% methanol extract at 400 mg/kg (p<0.05) and the aqueous residue at 400 mg/kg (p 0.01) significantly lowered blood glucose levels in streptozotocin-induced diabetic mice.

Conclusion

The results of this study revealed that the 80% methanol extract and solvent fractions of V. sinaiticum Benth leaves are endowed with antidiabetic activity.

In Vivo Hypolipidemic, Hypoglycemic, Antihyperglycemic, and In Vitro Antioxidant Effects of Podocarpus gracilis Leaf Extract and Fractions in Diabetic Mice

Background

Podocarpus gracilis is an evergreen, dioecious tree found in Ethiopia and other African nations. It can reach a height of 60 meters. Without any scientific validation, ethnobotanical studies conducted in Ethiopia revealed that the Podocarpus gracilis plant's leaf is consumed orally to treat diabetes mellitus. Hence, this study aims to evaluate the in vivo blood glucose level lowering, lipid-lowering, and in vitro-free radical scavenging responses of Podocarpus gracilis leaf extract and fractions on experimental mice induced with diabetes.

Methods

The in vitro antioxidant activity of PGC (Podocarpus gracilis) leaf extract was assessed by using a diphenyl-2-picrylhydrazyl (DPPH) assay. The oral glucose-loaded, normoglycemic, and streptozotocin- (STZ-) induced diabetic mouse models were employed. In the STZ-induced mice model, the leaf extract and solvent fractions activity on serum lipid and weight were also measured. The extract and fractions were tested at 100, 200, and 400 mg/kg dosages. One-way ANOVA was used to determine the statistical significance of BGL (blood glucose level) changes within and between groups, and Tukey's post hoc multiple comparisons were then performed.

Results

In the acute toxicity study of Podocarpus gracilis leaf extract and fractions, there was no evidence of animal mortality at the maximum dose of 2 g/kg during the observation period. The extract-treated group with normoglycemia revealed a significant lowering in BGL at the 4-hour mark of 27.4% (p < 0.001) and 25.2% (p < 0.01) at doses of 200 mg/kg and 400 mg/kg, respectively, compared to that in negative control. In the oral glucose tolerance test (OGTT) model, only 400 mg/kg treated groups at 120 min after exposure showed a BGL reduction of 31.17% which was statistically significant (p < 0.05) in comparison to the negative control. In the single-dose STZ-induced model, eighth-hour BGL measurements from CE 100, CE 200, CE 400, and GLC5 showed drops in BGL of 43.1%, 44.1%, 45%, and 47.3% from baseline fasting BGL values. In the repeated streptozotocin (STZ)-induced model, at all doses of leaf extract and fractions, the fasting BGL was significantly (p < 0.001) reduced. Moreover, the leaf extract and solvent fractions have shown a significant (p < 0.001) reduction of serum lipids such as LDL, TC, and VLDL, and at the same time, it increases HDL at 14 days with body weight gained. In the test for antioxidant activity, the half-maximal inhibitory concentrations (IC50) for leaf extract and the standard medication (ascorbic acid) were 8.2 μg/ml and 3.3 μg/ml, respectively. The IC50 value denotes the concentration of the sample required to scavenge 50% DPPH radicals.

Conclusion

The 80% hydromethanolic leaf extract and fractions of Podocarpus gracilis exhibited blood glucose lowering, lipid-lowering activity in normoglycemic, oral glucose tolerance test (OGTT) mode, and STZ-induced diabetic mice with weight gains. There is scientific support for the alleged traditional use as an antidiabetic, lipid-lowering, and antioxidant activity. The results need to be confirmed by future studies.

Evaluation of physicochemical parameters, acute and subchronic toxicities, and anti-diabetic activity of Spondias venulosa (Engl.) Mart. ex Engl. leaf extract on alloxan-induced diabetic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Spondias venulosa is a medicinal plant whose leaves are popularly used for decades in Northeast Nigeria as a first-choice medicinal plants for the treatment of diabetes. This claim has not been proven scientifically.

AIM OF THE STUDY

The present study was carried out to determine the physicochemical profiles, acute, sub-chronic toxicities, and antidiabetic activity the leaf extract in alloxan-induced diabetic rats.

MATERIALS AND METHODS

The physicochemical parameters of S. venulosa leaves, acute, subchronic toxicities, and antidiabetic activity in alloxan-induced diabetic rats were determined using standard procedures. All physicochemical parameters were carried out triplicate. Acute and subchronic toxicity studies were carried out following OECD guidelines by administering maximum extract dose of 2000 mg/kg orally to Wistar rats. Subchronic toxicity and antidiabetic studies were carried out in rats of opposite sexes at doses 300, 600, and 1200 mg/kg (orally).

RESULTS

Results obtained showed that the moisture content, water soluble extractive, and organic matter had values of 4.98 ± 1.01, 12.04 ± 1.24 and 1.01 ± 0.01% w/w respectively. The metallic contents of the methanol leaf extract revealed the presence of zinc with value of 12.01 ± 1.01 ppm (normal range:< 100 mg/kg DM) and copper with value of 6.24 ± 2.14 ppm (normal range:< 30 mg/kg DM). Oral median lethal dose (LD₅₀) was estimated to be greater than 2000 mg/kg since the extract did not produce any sign of toxicity or death in short term while, subchronic toxicity study showed that there was no significant weight loss in the rats after 28 days of extract administration. All hematology and biochemical parameters showed no elevated values when compared to the control group (p < 0.05). Histopathological examinations of major organs do not show signs of organ damages which indicate that the extract was safe at the doses administered. Oral administration of extract doses for 30 days reduced blood glucose levels in alloxan-induced diabetic rats in dose-dependent manner compared (p < 0.05) to standard drug (Glibenclamide).

CONCLUSIONS

Our study showed some physicochemical parameters of S. venulosa leaf which are essential for its identification from closely related species in traditional medicine. The study further showed that S. venulosa methanol leaf extract possessed antidiabetic activity, thus, justifying its use for the treatment of diabetes in Nigeria. However, there is need to identify and investigate the bioactive compound(s) responsible for the activity towards drug discovery.

Medicinal plants utilized in the management of epilepsy in Ethiopia: ethnobotany, pharmacology and phytochemistry

Epilepsy is a common central nervous system (CNS) disorder that affects 50 million people worldwide. Patients with status epilepticus (SE) suffer from devastating comorbidities and a high incidence of mortalities. Antiepileptic drugs (AEDs) are the mainstream treatment options for the symptomatic relief of epilepsy. The incidence of refractory epilepsy and the dose-dependent neurotoxicity of AEDs such as fatigue, cognitive impairment, dizziness, attention-deficit behavior, and other side effects are the major bottlenecks in epilepsy treatment. In low- and middle-income countries (LMICs), epilepsy patients failed to adhere to the AEDs regimens and consider other options such as complementary and alternative medicines (CAMs) to relieve pain due to status epilepticus (SE). Plant-based CAMs are widely employed for the treatment of epilepsy across the globe including Ethiopia. The current review documented around 96 plant species (PS) that are often used for the treatment of epilepsy in Ethiopia. It also described the in vivo anticonvulsant activities and toxicity profiles of the antiepileptic medicinal plants (MPs). Moreover, the phytochemical constituents of MPs with profound anticonvulsant effects were also assessed. The result reiterated that a lot has to be done to show the association between herbal-based epilepsy treatment and in vivo pharmacological activities of MPs regarding their mechanism of action (MOA), toxicity profiles, and bioactive constituents so that they can advance into the clinics and serve as a treatment option for epilepsy.

Evaluation of in vivo Antidiabetic, Antidyslipidemic and in vitro Anti-Oxidant Activity of Extract and Solvent Fractions of Discopodium penninervum Hoschst Leaf in Mice: Normoglycemic and Streptozocin-Induced Model

BACKGROUND

Diabetes mellitus has become a huge global public health and economic issue. The shortcomings of current medicines, as well as their serious side effects, prompted a focused quest for natural medicinal agents. In Ethiopia, the leaf of Discopodium penninervum Hoschst has been utilized in the traditional health system to treat diabetes. The goal of this study was to confirm the anti-diabetic, anti-dyslipidemia, and anti-oxidant activity of Discopodium penninervum Hoschst leaf in both in vitro and in vivo.

METHODS

In the normoglycemic, glucose-loaded, and streptozotocin-induced diabetic mouse models, the blood glucose-lowering effects of extract and solvent fractions of the leaf of Discopodium penninervum Hoschst were tested. The weight and lipid profile of streptozotocin-induced diabetic mice were assessed after treatment with leaf extract and solvent fractions for 14 days. The DPPH test was used to assess the antioxidant activity of the plant leaf extract.

RESULTS

In the normoglycemic model and glucose loaded test, the leaf extract of Discopodium penninervum Hoschst demonstrated significant blood glucose decrease (34.1%, p<0.001) and 44.5%, p<0.001, respectively, when compared to the normal control. When compared to a diabetic control group, extract and solvent fractions significantly (p<0.001) reduced blood glucose levels on the 14th day in the streptozotocin-induced diabetic model. In addition, serum TC, STG, TG, LDL, and VLDL levels were reduced significantly (p<0.001). IC50 values of leaf extract and a standard medication (ascorbic acid) in the antioxidant activity test were 4.1g/mL and 10.23g/mL, respectively.

CONCLUSION

The hydro-alcoholic leaf extract and solvent fractions of Discopodium penninervum Hoschst leaves have demonstrated blood glucose-lowering effect, which justify ethnobotanical use, and can therefore be used as a good insight for new anti-diabetic medication source with a call for additional studies.

Antidiabetic Activity of Mung Bean or Vigna radiata (L.) Wilczek Seeds in Alloxan-Induced Diabetic Mice

Introduction

Despite the development of oral hypoglycemic medications, diabetes and its associated complications continue to be significant clinical issues. The purpose of this study was to examine the antidiabetic effects of Vigna radiata (L.) Wilczek seeds in mice that had been given alloxan to cause diabetes.

Methods

In Swiss albino mice, diabetes was brought on by a single intraperitoneal injection of the drug alloxan (150 mg/kg). For 14 days, glibenclamide (5 mg/kg) and methanol extract of V. radiata seeds (100, 200, and 400 mg/kg) were given orally. Following oral administration of V. radiata to mice, the blood glucose levels (BGL) and body weight were measured at 7 and 14 days. The mice were sacrificed at the end of the trial, and blood samples were taken for the evaluation of insulin, glycated hemoglobin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), high-density lipoprotein (HDL), total cholesterol (TC), and triglyceride (TG) levels. It was determined how much glycogen was present in the liver. Additionally, the total phenolic and flavonoid contents of V. radiata were determined, along with the in vitro DPPH (2, 2 diphenyl-1-picrylhrazyl) free radical-scavenging activity. P < 0.05 was chosen as the cutoff for statistical significance.

Results

Following oral administration of V. radiata for 14 days, diabetic mice's BGL and bad cholesterol (TC and TG) levels significantly decreased, while HDL levels increased. Treatment with V. radiata significantly decreased the levels of AST, ALT, and glycated hemoglobin when compared with diabetes control. On the other hand, it raised insulin levels and the amount of liver glycogen. V. radiata underwent phytochemical analysis, which identified the presence of tannins, saponins, phenols, alkaloids, terpenoids, steroids, flavonoids, and glycosides. Per gram of V. radiata seed extract, the total phenolic content was 43.12 ± 3.14 mg of gallic acid equivalents, while the total flavonoid content was 38.35 ± 2.6 mg of quercetin equivalents. Ascorbic acid was shown to have an IC₅₀ value of 18.64 µg/ml during a DPPH-scavenging assay, while V. radiata had an IC₅₀ value of 73.35 µg/ml.

Conclusion

According to the findings of the current study, the methanolic extract of the seeds from the plant V. radiata possesses significant antidiabetic characteristics that are on par with those of the commonly used drug glibenclamide. Hence, V. radiata seems to be effective as a natural antidiabetic.

Amelioration of hyperglycemia and hyperlipidemia in a high-fat diet-fed mice by supplementation of a developed optimized polyherbal formulation

This study evaluated in vivo anti-diabetic and anti-obesity activity of a polyherbal formulation's methanolic extract containing an optimized ratio of edible seeds (Salvia hispanica, Chenopodium quinoa, Nelumbo nucifera). Diet-induced obese mice model (C57BL/6) was developed by feeding the mice a high-fat diet for 10 weeks resulting in hyperglycemia and obesity. Different doses (125, 250 and 500 mg/kg of body weight) of formulation were administered orally daily for 6 weeks. Fasting blood glucose and body weight were monitored throughout the study. At the end of the study, serum parameters were analyzed and histological examinations were performed. There was a significant reduction in fasting blood glucose levels and body weight in animal groups receiving polyherbal formulation. Lipid profile was improved as revealed by a reduction in serum triglycerides and total cholesterol. Histological study showed an improvement in liver, kidney and pancreatic sections of treated mice. High-performance thin layer chromatography was performed to identify the phytochemicals responsible for the above-mentioned bioactivities. The results revealed the presence of flavonoid (rutin) in seeds of N.nucifera and in the polyherbal formulation. For the first time, this study demonstrated the anti-diabetic and anti-obesity potential of the optimized formulation. The formulation can be used as a potential therapy for management of diabesity.

Evaluation of the Antidiabetic Activity of Hydromethanolic Roots Extracts of Rumex abyssinicus Jacq: (Polygonaceae) in Swiss Albino Mice

Introduction

Diabetes Mellitus isa chronic metabolic disorder that required long-lasting treatment. In Ethiopian traditional medicine practices, abundant plants have been used for the treatment of diabetes mellitus for a long period. The root of Rumex abyssinicus is employed for the treatment of diabetes mellitus by Ethiopians. This study aimed to investigate the antidiabetic activity of the crude extract of Rumex abyssinicus root in Swiss albino mice.

Methods

Cold maceration technique and hydro methanolic (80% methanol) solvent with occasionally shaking were employed during the crude extraction processes. To evaluate the antidiabetic activity of the crude extract, normoglycemic, glucose-loaded, and streptozotocin-induced diabetic models were used. In each model, the overnight fasted mice were randomly divided into five groups for normoglycemic and glucose-loaded models as a negative control, positive control, and three tested groups, whereas, in streptozotocin-induced diabetic models, the mice were grouped into six groups like one diabetic and one normal negative control groups, three diabetic tested groups, and one diabetic positive group. Each group comprised six mice. For all models, the tested groups received the crude extract at 100, 200, and 400 mg/kg doses, both diabetic and nondiabetic negative control groups received 10 ml/kg distilled water, and positive groups received 5 mg/kg glibenclamide.

Results

The crude extract of the plant did not show any sign of toxicity up to 2000 mg/kg dose. In normoglycemic and oral glucose tolerance tests, the crude extract significantly (p < 0.01) reduced the blood glucose level at 200 and 400 mg/kg doses. In the streptozotocin-induced diabetes models, a significant effect was observed at all tested doses.

Conclusion

The finding of this study revealed that the crude extract of the plant owned antidiabetic activity and supports the traditional use of Rumex abyssinicus root for the treatment of diabetes mellitus.

Pharmacological evaluation of medicinal plants with antidiabetic activities in Ethiopia: A review

Diabetes mellitus is a serious, chronic disease that occurs either when the pancreas does not produce enough insulin, or when the body can't effectively use insulin. Herbal medicines have been commonly used by diabetic patients for the treatment of diabetes mellitus. To include findings from different studies, publications related to in vivo and invitro antidiabetic activities of medicinal plants in Ethiopia were searched from different databases, such as Web of Science, Google Scholar, Medline, Scopus, and PubMed, using English key terms. Different medicinal plant parts were used experimentally for antidiabetic effects in Ethiopia. Among these, leaves (69%) were the most commonly investigated medicinal plant parts followed by roots (14%) and seeds (7%). Most of the investigations were completed with hydro-methanolic extracts to obtain a higher percentage of yield. Medicinal plants such as Thymus schemperi R, Thymus vulgaris L, Hagenia abyssinica, Aloe megalacantha baker, Aloe moticola Reyonolds, Aloe pulecherrima Gilbert & sebseb, Bersama abyssinica fresen, and Rubus Erlangeri Engl have shown in vitro α-amylase inhibitory activity. However, only Hagenia abyssinica, Thymus schemperi R, and Thymus vulgaris L have exhibited α-glucosidase inhibitory activity. Likewise, only the extract of Aloe pulecherrima Gilbert & sebseb posses’ maltase and sucrose inhibitory activity. In vivo antidiabetic activity were conducted for the extract of medicinal plants such as A. remota, S. rebaudiani, T. schemperi, T. vulgaris, H. abyssinica, C. aurea, D. stramonium, A. megalacantha, A. moticola, A.integrifolia, A. pulecherrima, B. grandiflorum, B. abyssinica, P. schimperiana, M. stenopetala, C. aure, J. schimperiana, T. brownie, C. macrostachys, I. spicata, O. integrifolia, C. abyssinica, R. Erlangeri, L. culinaris, A. camperi, A. polystachyus, A. ilicifalius, C. tomentosa, and C. Edulis. This review gives collective evidence on the potential antidiabetic activities of medicinal plants in Ethiopia. Moreover, further studies are recommended to substantiate the use of these medicinal plants as an antidiabetic agent.

Antidiabetic Activity of Hydromethanolic Extract of Crude Dorstenia barnimiana Root: Validation of In Vitro and In Vivo Antidiabetic and Antidyslipidemic Activity

Background

Despite modern therapeutic armamentaria, DM remains a 21st-century public health menace. Novel phytomedicines are a rapidly expanding focus of research. The juice of Dorstenia barnimiana roots has long been used for the treatment of diabetes mellitus in traditional Ethiopian medicine, but its efficacy has not been supported by in vitro or in vivo scientific study. To investigate this, the present work was performed.

Methods

In this experimental study, simple random sampling was applied. Healthy male mice were used in normoglycemic and oral glucose-tolerance test (OGTT) models. Streptozotocin (IP, 150 mg/kg)–administered diabetic male mice were utilized. Animals were randomly divided into five groups of six each. Group I received 10 mL/kg distilled water, groups II–IV received 100 (DB100), 200 (DB200), and 400 (DB400) mg/kg crude extract, respectively, and group V received glibenclamide 5 mg/kg. A sham group (group VI) was added that received 10 mL/kg distilled water. All treatments were given orally. FBG, serum-lipid profiles, and body-weight changes were then measured. In vitro α-amylase inhibitory activity was also evaluated.

Results

The doses were atoxic up to 2,000 mg/kg. There was α-amylase inhibition activity of 67.52% at 500 μg/mL with an IC₅₀ of 4.595 μg/mL. The OGTT revealed an antihyperglycemic effect of the crude extract. This was not attributed to a hypoglycemic side effect. In the diabetic mouse model, it shrank FBG levels remarkably. There were also significant reductions in serum TC, TGs, VLDL-C, and LDL-C. Nevertheless, HDL-C and body-weight levels returned.

Conclusion

The present study confirmed the safety and promising in vivo antidiabetic and antidyslipidemic activity of D. barnimiana, thus corroborating the traditional claim.

Methanolic Extract of Myrsine africana Leaf Ameliorates Hyperglycemia and Dyslipidemia in Alloxan-Induced Diabetic Albino Mice

Background. Diabetes mellitus is one of the leading public health problems globally, and its prevalence is increasing in Ethiopia. The current drugs for people with diabetes are costly, less effective, and less safe with a challenging administration method. Thus, globally, the need for alternative herbal antidiabetic medicines is increasing. In the previous studies, antioxidant activities have been seen in crude extracts of M. africana leaves, which is an auspicious sign of antidiabetic property. Accordingly, this study has evaluated the antidiabetic and antidyslipidemic activities of methanolic extract of M. africana leaves. Methods. Hypoglycemic and antihyperglycemic activities of the three doses (250 mg/kg, 500 mg/kg, and 1000 mg/kg) of crude methanolic extract of M. africana leaf were studied on normoglycemic, oral glucose-loaded, and alloxan-induced diabetic mice models. The effect of the extract on diabetic dyslipidemia, insulin and glycated hemoglobin levels, carbohydrate-metabolizing enzymes, and body weight was also studied in alloxan-induced diabetic mice. Glibenclamide (5 mg/kg) was used as a standard drug in all cases. Data analysis was carried out using mixed-design ANOVA. A $P$ value of ≤0.05 was considered a statistically significant difference. Results. The methanolic extract of M. africana leaf did not show acute toxicity up to the dose of 5000 mg/kg and showed better glucose utilization in the oral glucose tolerance test. After 14 days of treatment, M. africana leaf extract decreased the blood glucose level, glycated hemoglobin, glucose-6-phosphatase, and fructose-1-6-bisphosphatase in diabetic mice. In contrast, it increased hexokinase and insulin levels in diabetic mice. Moreover, weight loss and dyslipidemia profiles have been corrected significantly in diabetic mice. Conclusion. M. africana leaves showed antihyperglycemic and antidyslipidemic effects in alloxan-induced diabetic mice. That suggests M. africana may be a potential treatment option for diabetes in the future. However, further molecular studies are required to analyze the mechanisms.

In vivo hypoglycemic, antihyperglycemic and antidyslipidemic effects of the solvent fractions of Hagenia abyssinica leaves in mice

Background

Hagenia abyssinica leaves have been used traditionally for the management of different diseases including diabetes mellitus (DM) although the antidiabetic effect of different solvent fractions of hydromethanol H. abyssinica leaf extract has not been scientifically studied. Thus, this study was conducted to investigate the in vivo hypoglycemic, antihyperglycemic and antidyslipidemic effects of the solvent fractions of Hagenia abyssinica leaf extract.

Methods

The antidiabetic effect of the solvent fractions was evaluated in normal, oral glucose loaded and streptozotocin-induced diabetic mice. Hypoglycemic, antihyperglycemic, antidyslipidemic activities and effect on body weight change were evaluated after administration of three different doses of the solvent fractions (100, 200, and 400 mg/kg). One-way ANOVA followed by Tukey's post hoc test was used for data analysis, and p<0.05 was considered as statistically significant.

Results

The crude hydromethanol extract of H. abyssinica leaves did not show any sign of toxicity at the dose of 2000 mg/kg in mice. In normoglycemic mice, both aqueous and ethyl acetate fractions of H. abyssinica leaves showed significant (P<0.05) hypoglycemic activity. In oral glucose loaded mice, the two doses of the aqueous fraction, 200 mg/kg (p<0.05) and 400 mg/kg (p<0.001), showed a significant antihyperglycemic effect at 60 and 120 minute post-oral glucose loading while the ethyl acetate fraction showed significant antihyperglycemic effect at 60 (P<0.05 for 200 mg/kg and P<0.001 for 400 mg/kg) and 120 min (P<0.01 for 400 mg/kg) post-oral glucose loading. In single dose-treated diabetic mice, all doses of the solvent fractions caused a significant (P<0.05) reduction in blood glucose level except 100 mg/kg of the aqueous and chloroform fractions. Additionally, repeated daily treatment with the aqueous fraction significantly reduced hyperglycemia, body weight loss, and improved dyslipidemia of diabetic mice.

Conclusion

This study has revealed that the solvent fractions of H. abyssinica leaves possess in vivo blood-glucose-lowering activities on normal, oral glucose loaded, and streptozotocin-induced diabetic mice. Additionally, the aqueous fraction prevented diabetic body weight loss and dyslipidemia in mice after repeated daily dose administration.

In Vivo Antimalarial Activity of Leaf Extracts and a Major Compound Isolated from Ranunculus multifidus Forsk

The leaves of Ranunculus multifidus Forsk. are traditionally used for the treatment of malaria in several African countries. In the present study, 80% methanol (RM-M) and hydrodistilled (RM-H) extracts of fresh leaves from R. multifidus and its major constituent anemonin were tested for their in vivo antimalarial activity against Plasmodium berghei in mice. Anemonin was also tested for its in vitro antimycobacterial activity against Mycobacterium smegmatis and M. abscessus in a microbroth dilution assay, and bacterial growth was analyzed by OD measurement. The isolation of anemonin from RM-H was carried out using preparative thin layer chromatography (PTLC). The chemical structures of anemonin and its hydrolysis product were elucidated using spectroscopic methods (HR–MS; 1D and 2D-NMR). Results of the study revealed that both RM-M and RM-H were active against P. berghei in mice, although the latter demonstrated superior activity (p < 0.001), as compared to the former. At a dose of 35.00 mg/kg/day, RM-H demonstrated a chemosuppression value of 70% in a 4-day suppressive test. In a 4-day suppressive, Rane’s and prophylactic antimalarial tests, anemonin showed median effective doses (ED₅₀s) of 2.17, 2.78 and 2.70 μM, respectively. However, anemonin did not inhibit the growth of M. smegmatis and M. abscessus.

Medicinal Plant Extracts Evaluated In Vitro and In Vivo for Antidiabetic Activities in Ethiopia: Bases for Future Clinical Trials and Related Investigations

Background

Diabetes mellitus (DM) is a metabolic disorder characterized by a persistent rise in the blood glucose level resulting from defects in cellular insulin function, secretion, or both, which affects millions of people every year. Several drawbacks have been stated with the use of marketed antidiabetic medicines such as drug resistance, adverse effects, toxicities, and even costs. Due to these several limitations, searching for novel antidiabetic medicines from medicinal plants (MPs) is becoming an active area of research. Therefore, MPs are exemplary sources of medicines with many accessible agents being obtained from them because numerous active constituents are isolated from them for direct use as pharmacological medicines or act as lead compounds. This paper was aimed to synthesize a concluding remark using in vitro and in vivo evaluations of extracts and fractions for antidiabetic potentials in Ethiopia, which can be used to direct future clinical trials and related investigations.

Method

So as to get data on the different investigations, publications related to experimental evaluations on animal diabetic models in Ethiopia were searched from databases, such as Google Scholar, Web of Science, Medline, PubMed, and Scopus using English key terms.

Results

In this paper, about 37 research findings based on data from various areas of Ethiopia published until the end of November 2020 were included. A total of 37 MP species extracts and fractions belonging to 19 families have been revealed in vitro or in vivo for potential antidiabetic activities. Crude extracts were carried out mostly by hydromethanolic whereas fractions were done mostly by chloroform. Leaves were the most commonly experimentally investigated plant part. Among the MP species experimentally studied, the most frequently used to treat DM in Ethiopia were Thymus schimperi Ronniger (Lamiaceae), Moringa stenopetala (Baker f.; Moringaceae), Ajuga remota Benth (Lamiaceae), and Datura stramonium Linn. (Solanaceae).

Conclusion

This paper gives aggregate evidences on the potential antidiabetic activities of MPs in Ethiopia. Antidiabetic MPs used in Ethiopia represent crucial input for the future development of novel antidiabetic drugs. To this end, more pharmacological and toxicological investigations need to be considered to prove the safety of constituents obtained from these MPs. Finally, we recommend upcoming research to ensure future success in the clinical study and development of novel medicines for DM treatment from these frequently evaluated MPs.

Evaluation of Antidiabetic and Antioxidant Activity of Leaf Extract and Solvent Fractions of Hypoestes forskaolii (Val) (Acanthaceae) in Mice

Background

Currently, there is a demand for new antidiabetic drugs from natural therapeutic agents, and diabetes mellitus disease is global epidemic. The leaf of Hypoestes forskaolii has been used in the traditional health system for the management of diabetes mellitus in Ethiopia and Eritrea. The aim of this study was to evaluate in vivo antidiabetic, antihyperlipidemic and in vitro antioxidant activity of leaf extract and solvent fractions of the leaf of H. forskaolii (Vahl) in mice.

Methods

The blood glucose-lowering activities of leaf extract and solvent fractions of the leaf of H. forskaolii were screened in the normoglycemic, glucose loaded, and streptozotocin-induced diabetic mice models. In the treatment of streptozotocin-induced diabetic mice with leaf extract and solvent fractions, weight and lipid profile was measured. Antioxidant activity of the plant leaf extract was determined using DPPH assay.

Results

The leaf extract of H. forskaolii showed significant blood glucose reduction in the normoglycemic model and glucose loaded test at doses of 200 mg/kg (34.1%, p < 0.001 and 55.5%, p < 0.001), respectively, as compared to the normal control. In the streptozotocin-induced diabetic model, extract and solvent fractions significantly (p < 0.001) reduced blood glucose level at all tested doses (100mg/kg, 200mg/kg and 400mg/kg) on the 14th day as compared to diabetic control. In addition, a significant reduction (p < 0.001) of serum TC, VLDL, LDL, TG was observed. In the antioxidant activity test, the IC₅₀ values of extract and a standard drug (ascorbic acid) were 4.87µg/mL and 15.7µg/mL, respectively.

Conclusion

The present study showed that the methanolic leaf extract and solvent fractions of H. forskaolii have antidiabetic, and antioxidant activity that provides a scientific support for the local use of the plant leaves in the treatment of diabetes.

Evaluation of In Vivo Antidiabetic, In Vitro α-Amylase Inhibitory, and In Vitro Antioxidant Activity of Leaves Crude Extract and Solvent Fractions of Bersama abyssinica Fresen (Melianthaceae)

Background.

The leaves of Bersama abyssinica are used for the treatment of diabetes mellitus in folk medicine system of Ethiopia. The present study was done based on the traditional claim of B abyssinica for the treatment of diabetes mellitus.

Methods.

The α-amylase inhibition and antioxidant activities of B abyssinica extracts were evaluated by using 3,5-dinitrosalicylic acid method and diphenyl-2-picrylhydrazyl assay model, respectively. Blood glucose lowering activity of the extracts was studied in 4 animal models; normoglycemic, oral glucose loaded, and streptozotocin-induced diabetic mice models.

Results.

Among the extracts, the crude extract showed the highest α-amylase enzyme inhibition activity with an IC₅₀ of 6.57 μg/mL. The water fraction showed the strongest antioxidant activity with an IC₅₀ of 3.43 μg/mL. The crude extract at doses of 200, and 400 mg/kg showed significant (P < .05) hypoglycemic activity in normoglycemic mice. All doses of the crude extract significantly (P < .05) reduced blood glucose levels of oral glucose-loaded mice. In streptozotocin-induced diabetic mice models, both the crude and solvent fractions showed a significant (P < .05) blood glucose lowering effect as compared with the negative control group post 8 hour treatment.

Conclusion.

The results demonstrated the beneficial biochemical effects of B abyssinica extract by inhibiting α-amylase and scavenging the free radicals. The crude extract and solvent fractions of B abyssinica had significant blood glucose lowering effect in all animal models.

Efficacy, safety and phytochemistry of medicinal plants used for the management of diabetes mellitus in Ethiopia: a systematic review

Background

Despite tremendous developments in synthetic medicine, medicinal plants are still commonly used for the management of diabetes mellitus. This study synthesized scientific evidence on commonly used medicinal plants for the management of diabetes mellitus (DM) in Ethiopia.

Methods

Databases (PubMed, Cochrane, CINAHL and Google Scholar) have been thoroughly sought and evidence was synthesized.

Results

Thirty studies conducted anti-diabetic activities studies on 19 medicinal plants in Ethiopia. Most of the studies were in vivo studies (25). Others include; clinical study (1), in vitro studies (2), and both in vivo and in vitro study (2). Trigonella foenum-graecum L., clinical study, showed an improved lipid profile in type II diabetic patients. Comparable blood sugar level (BSL) lowering effect to glibenclimide was observed with Persea Americana and Moringa stenopetala. Noteworthy in vitro half maximal inhibitory concentration (IC 50) of Aloe megalacantha B and Aloe monticola R were observed. Animal model studies demonstrated the relative safety of the plants extract and phytochemistry studies showed various components.

Conclusion

Medicinal plants used for management of diabetes mellitus in Ethiopia are worthy for further study for pharmacologically active ingredients and clinical evaluation.

Evaluation of Antidiabetic Activity of Ajuga integrifolia (Lamiaceae) Root Extract and Solvent Fractions in Mice

Traditional healers and the community have used the roots of Ajuga integrifolia for the treatment of diabetes mellitus. It is not scientifically validated for its antidiabetic activity previously. Therefore, the objective of the present study was to determine the hypoglycemic and antidiabetic activity of Ajuga integrifolia. Ajuga integrifolia roots' crude extract and solvent fractions were prepared. The doses of 100 mg/kg, 200 mg/kg, and 400 mg/kg of crude root extract and solvent fractions were used on normoglycemic, oral glucose loaded, and streptozotocin-induced diabetic mice models to determine their hypoglycemic and antihyperglycemic activities. The crude extract and solvent fractions' effect on bodyweight was also evaluated on streptozotocin-induced diabetic mice. A standard drug in all cases was glibenclamide (5 mg/kg), and the blood glucose level was measured by using a glucose meter. Data analysis was performed by using Statistical Package for Social Sciences version 21. One-way analysis of variance followed by Tukey's post hoc multiple comparison test was used to analyze the data. p value < 0.05 was considered statistically significant. Hydromethanolic crude extract and its aqueous fraction of Ajuga integrifolia root showed a considerable blood glucose lowering activity at all doses. Both the repeated daily doses of the crude extract and the repeated daily doses of the aqueous fraction of Ajuga integrifolia root extract revealed the similar effect in lowering the fasting blood glucose level in streptozotocin-induced diabetic mice models. It was also found that groups treated with the Ajuga integrifolia at the doses of 200 mg/kg and 400 mg/kg showed significant (p < 0.05) bodyweight improvement at the 14^th day of treatment compared to the respective baseline bodyweight, and the diabetic control group showed significant (p < 0.01) reduction in bodyweight at the 14^th day compared to the baseline. This study revealed that crude extract and solvent fractions of Ajuga integrifolia root possess significant antidiabetic activity which supports its traditional use for the treatment of diabetes mellitus.

Nutritional Effects of the Enteral Nutritional Formula on Regulation of Gut Microbiota and Metabolic Level in Type 2 Diabetes Mellitus Mice

PURPOSE

Due to the adverse effects of antidiabetic drugs, nowadays, nutraceuticals have been of much interest to investigators. Therefore, the present study aimed to explore the potential effects of enteral nutritional (EN) formulas on the gut microbiota and metabolic regulation of type 2 diabetes mellitus (T2DM) mice and compare the differences between whey protein and soy protein.

METHODS

EN formulas made of whey protein or soy protein were administered for five weeks and then mice tissue samples were obtained to examine the metabolic parameters and histopathology of the pancreas, liver, jejunum and colon. 16S rRNA V3-V4 region gene sequencing was used to analyze the changes in the gut microbiota.

RESULTS

After the five-week intervention, the alpha diversity had recovered slightly, and the soy protein group (SPG) achieved a better effect than the whey protein group (LPG). The overall composition of gut microbiota was regulated. The abundance of Bacteroidetes and TM7 had raised significantly and the abundance of Firmicutes and Deferribacteres had declined after treatment, with no significant difference between the LPG and SPG. The types of beneficial bacteria were increased at the genus and species level. The level of hexokinase (HK) and pyruvate kinase (PK) had significantly recovered and inhibited the level of α-glucosidase. In addition, the EN formulas treatment reduced the levels of inflammatory factor (TNF-α) in liver and muscle. The level of glucose transporter type 2 (GLUT-2) levels in the liver and intestine also significantly increased. Moreover, the metabolism regulation of the SPG was better than that of the LPG. The EN formulas treatment improved the pancreas, liver, jejunum and colon histology.

CONCLUSION

The EN formulas regulated the overall structure of the gut microbiota and improved the metabolic level in streptozotocin/high-fat diet (STZ/HFD) diabetic mice. Therefore, EN formula may potentially become an effective nutritional adjunctive therapy for T2DM.

In vivo anti-malarial activity of the hydroalcoholic extract of rhizomes of Kniphofia foliosa and its constituents

BACKGROUND

Kniphofia foliosa is a flamboyant robust perennial herb which has dense clumps and tick upright rhizomes with leaves at the base. In Ethiopia, it has several vernacular names including Abelbila, Ashenda, Amelmela, Yeznjero Ageda, Shemetmetie and Yezinjero Ageda. The plant is endemic to Ethiopian highlands, where its rhizomes are traditionally used for the treatment of malaria, abdominal cramps and wound healing. In the present study, the 80% methanol extract of K. foliosa rhizomes and its constituents are tested against Plasmodium berghei in mice.

METHODS

Isolation was carried out using column and preparative thin layer chromatography (PTLC). The chemical structures of the compounds were elucidated by spectroscopic methods (ESI-MS, 1D and 2D-NMR). Peters' 4-day suppressive test against P. berghei in mice was utilized for in vivo anti-malarial evaluation of the test substances.

RESULTS

Two compounds, namely knipholone and dianellin were isolated from the 80% methanolic extract of K. foliosa rhizomes, and characterized. The hydroalcoholic extract (400 mg/kg) and knipholone (200 mg/kg) showed the highest activity with chemosuppression values of 61.52 and 60.16%, respectively. From the dose-response plot, the median effective (ED₅₀) doses of knipholone and dianellin were determined to be 81.25 and 92.31 mg/kg, respectively. Molecular docking study revealed that knipholone had a strong binding affinity to Plasmodium falciparum l-lactate dehydrogenase (pfLDH) target.

CONCLUSION

Results of the current study support the traditional use of the plant for the treatment of malaria.

Evaluation of Antidiabetic Activity of the Leaf Latex of Aloe pulcherrima Gilbert and Sebsebe (Aloaceae)

The leaf latex of Aloe pulcherrima has been used as remedy for diabetes mellitus. This was carried out to determine in vitro and in vivo antidiabetic activities of the leaf latex of Aloe pulcherrima. Methods. Sucrase and maltase inhibitory activity of the leaf latex of A. pulcherrima was determined in glucose oxidase assay, and α-amylase inhibitory activity was determined in dinitrosalicylic acid assay. Normoglycemic, glucose-loaded, and streptozotocin-induced diabetic mice were treated orally to determine blood glucose lowering activity of the latex. Effect of the latex on serum lipid level and body weight was measured in streptozotocin-induced diabetic mice. Additionally, DPPH assay was used to determine free radical scavenging capacity of the latex. Results. Antioxidant activity of the latex was concentration dependent; the strongest inhibition was measured at 800 μg/ml (80.57%). The leaf latex of A. pulcherrima inhibited sucrase (IC₅₀ = 2.92 μg/ml), maltase (IC₅₀ = 11.81 μg/ml) and α-amylase (IC₅₀ = 14.92 μg/ml) enzymes. All doses of the leaf latex induced hypoglycemic effect after 4 h in normal mice, and low dose of the latex did not show significant effect after 6 h. Glucose reduction of the leaf latex of A. pulcherrima was significant (p < 0.05) in oral glucose-loaded mice compared to the vehicle control. Blood glucose level of diabetic mice was significantly (p < 0.05) reduced on week one and weak two in a streptozotocin-induced diabetic mouse model. Glucose reduction increased with increasing the doses of the leaf latex of A. pulcherrima on week one (p < 0.05 (200 mg/kg), p < 0.01 (400 mg/kg), and p < 0.001 (600 mg/kg)). Administration of the leaf latex of A. pulcherrima for two weeks significantly (p < 0.05) improved diabetic dyslipidemia and body weight of diabetic mice. Conclusion. The study confirmed that the leaf latex of the plant showed a significant antidiabetic activity justifying the traditional uses of the plant.

Evaluation of Antidiabetic and Antioxidant Potential of Hydromethanolic Seed Extract of Datura stramonium Linn (Solanaceae)

Background

Nature has gifted a variety of phytochemicals having a potential effect against diabetes mellitus. Datura stramonium has been used as a remedy for the treatment of diabetes mellitus. The study aimed to determine the in vivo antidiabetic potential of hydromethanolic seed extract of the plant.

Methods

Dried seeds of Datura stramonium were macerated in hydromethanol. Three doses (100, 200, and 400 mg/kg) of the seed extract were given orally to normoglycemic, glucose-loaded, and Streptozocin-induced diabetic mice. Diphenyl-1-picrylhydrazine (DPPH) assay was employed to determine antioxidant activity of the seed extract.

Results

All doses of hydromethanolic seed extract of D. stramonium were devoid of any significant hypoglycemic effect in normoglycemic mice compared to the negative control group. Acute glucose reduction was significant (P<0.05 at 100, P<0.01 at 200 and 400 mg/kg) with respect to negative control in oral glucose-loaded mice. All doses of seed extract significantly (P<0.0l) reduced blood glucose level on weeks 1 and 2 in STZ-induced daily-treated diabetic mice. The seed extract at the doses of 200 and 400 mg/kg significantly (P<0.05) improved the body weight of diabetic mice on weeks 1 and 2. A low (100 mg/kg) dose of the seed extract delayed and significantly (P<0.05) increased body weight of mice on week 2 compared to negative control. The finding showed that the antioxidant activity of the hydromethanolic seed extract was concentration dependent and comparable with ascorbic acid. IC50 of the seed extract and ascorbic acid was found to be 11.95 and 5.07 mg/mL, respectively.

Conclusion

The findings of the study showed that hydromethanolic seed extract of Datura stramonium endowed significant antihyperglycemic and antioxidant activity.

Evaluation of in vitro and in vivo Anti-Diabetic, Anti-Hyperlipidemic and Anti-Oxidant Activity of Flower Crude Extract and Solvent Fractions of Hagenia Abyssinica (Rosaceae)

BACKGROUND

The flower of Hagenia abyssinica (Rosaceae) has been used in traditional health systems to treat diabetes mellitus in Ethiopia and Tanzania. However, the antidiabetic activity of this medicinal plant is not scientifically validated and authenticated. The present study aimed to investigate the in vitro and in vivo anti-diabetic activity of flower crude extract and solvent fractions of Hagenia abyssinica.

METHODS

The in vitro α-amylase inhibition and antioxidant activity of the crude extract and solvent fractions of Hagenia abyssinica were evaluated by using 3,5-dinitrosalicylic acid (DNSA) and diphenyl-2-picrylhydrazyl (DPPH) assay model, respectively. Blood glucose lowering activity of 80% methanolic flower crude extract and solvent fraction was studied in four animal models: normoglycemic mice model, oral glucose loaded mice model, single dose-treated streptozotocin-induced diabetic mice model, and repeated dose-treated streptozotocin-induced diabetic mice model. The effect of the crude extract and solvent fraction of Hagenia abyssinica on diabetic lipid profile and body weight was also studied.

RESULTS

The acute toxicity study of Hagenia abyssinica flower extract did not show mortality in the animals at the limit dose of 2g/kg during the observation period. The result of α-amylase enzyme inhibition activity was found in a dose-dependent manner, the strongest activity was shown by ethyl acetate fraction (54.23% inhibition at 800 μg/mL) compared to the standard acarbose having 91.87% inhibition at 800 μg/mL. Among these extracts, the crude extract had the highest antioxidant activity (58.38% inhibition at 500 μg/mL). The crude extract of H. abyssinica showed significant blood glucose-lowering effect on normoglycemic mice and oral glucose loaded mice. In streptozotocin-induced diabetic mice model, the crude extract and ethyl acetate fraction significantly decreased the fasting blood glucose level after 14 days of treatment. There were significant reductions in serum total cholesterol, serum triglycerides, very low-density lipoprotein, and low-density lipoprotein. However, there were significant increments in body weight and high-density lipoprotein as compared to untreated diabetic mice.

CONCLUSION

The result demonstrated the beneficial biochemical effects of Hagenia abyssinica extract by inhibiting α-amylase, scavenging diphenyl-2-picrylhydrazyl (DPPH) and improving serum lipid profile levels. The flower crude extract and solvent fractions of Hagenia abyssinica are effective in lowering blood glucose levels in diabetic and normoglycemic mice. The claimed traditional use as antidiabetic has scientific ground.

Galangin controls streptozotocin-caused glucose homeostasis and reverses glycolytic and gluconeogenic enzyme changes in rats

Galangin is a natural compound with anticancer, anti-inflammatory, and antioxidant properties. However, the ameliorating effect of streptozotocin (STZ)-induced glucose homeostasis has not yet been evaluated. Hence, this study was aimed at exploring the role of galangin in STZ-induced glucose homeostasis, glycolytic and gluconeogenic enzyme changes in rats. STZ-treated rats were characterised by increased plasma glucose and glycosylated haemoglobin and decreased plasma insulin and haemoglobin compared with the normal cage. Administration of galangin to STZ-treated rats effectively reversed the adverse biochemical and haematological changes. Significant alterations in glycogen levels as well as glycolytic and gluconeogenic enzyme activities were witnessed in STZ-treated rats, and these changes were reversed upon treatment with galangin. The compound exerts potent anti-hyperglycemic effects by regulating the glucose homeostasis and reversing the glycolytic and gluconeogenic enzyme changes in rats. However, the exact mechanism through which galangin prevents diabetic complications needs to be studied in detail.

Antidiabetic Activity of Extracts of Terminalia brownii Fresen. Stem Bark in Mice

Background

Diabetes mellitus is a chronic metabolic disorder that imposes a huge health and economic burden on societies. Because the currently available medications have many drawbacks, it is important to search for alternative therapies. Medicinal plants used in traditional medicines are ideal candidates. Hence, this study was undertaken to investigate the antidiabetic activity of crude extract and solvent fractions from the stem bark of Terminalia brownii Fresen. (Combretaceae) in mice.

Materials and Methods

The in vitro α-amylase inhibition assay was performed using the chromogenic 3, 5-dinitrosalicylic acid (DNSA) method while the antihyperglycemic activity was assessed using three mouse models: streptozotocin-induced diabetic mice, normoglycemic mice, and oral glucose challenged mice. Experimental diabetes was induced by a single intraperitoneal injection of streptozotocin at a dose of 150 mg/kg and animals with fasting blood glucose level (BGL) >200 mg/dL were considered diabetic. Glibenclamide (5 mg/kg) was used as a standard drug. Fasting BGL and body weight were used to assess the antidiabetic activity. The result was analyzed using GraphPad Prism software version 8 and one-way ANOVA followed by Tukey’s post hoc test with p<0.05 considered as statistically significant.

Results

The crude extract of T. brownii at all tested dose levels (250, 500 and 750 mg/kg) showed a significant BGL reduction in all the three animal models. Moreover, the ethyl acetate and aqueous fractions (at 500 mg/kg) significantly (p<0.01) reduced the BGL in the streptozotocin induced diabetic model. The crude extract and different solvent fractions also showed a dose-dependent in vitro α-amylase inhibitory activity and improvement of body weight.

Conclusion

T. brownii crude extract and its solvent fractions showed a significant antihyperglycemic activity in STZ induced diabetic mice, hypoglycemic activity and improvement of oral glucose tolerance in normal mice.

Antidiabetic and Anti-hyperlipidemic Effects of the Crude Hydromethanol Extract of Hagenia abyssinica (Rosaceae) Leaves in Streptozotocin-Induced Diabetic Mice

BACKGROUND

The leaves of Hagenia abyssinica (Rosaceae) have been used traditionally for the management of diabetes mellitus. Thus, this study aimed to evaluate the antidiabetic and anti-hyperlipidemic activity of Hagenia abyssinica leaves crude extract in streptozotocin-induced diabetic mice.

METHODS

Antidiabetic and anti-hyperlipidemic activity of the crude extract of Hagenia abyssinica was studied in streptozotocin-induced diabetic mice. The effects of the extract on fasting blood glucose level, body weight, and serum lipid profiles were analyzed. One-way ANOVA followed by Tukey's post hoc test was used for data analysis and p<0.05 was considered as statistically significant.

RESULTS

Hagenia abyssinica leaves crude extract showed significant (p<0.05-p<0.001) blood-glucose-lowering activity. Moreover, the crude extract of H. abyssinica reduced the fasting blood glucose level by 23.21%, 38.20%, 43.53%, and 58.99%, respectively, for CE100, CE 200, CE 400, and GLC 5 mg/kg on the 14th day of treatment. After diabetic mice were treated with H. abyssinica (100, 200 and 400 mg/kg) for 14 days, there was a significant decrease in serum total cholesterol, very-low-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and serum triglyceride and a significant increase in body weight, and HDL-cholesterol level as compared to diabetic control.

CONCLUSION

The present findings revealed that H. abyssinica leaves could be useful for the management of diabetes mellitus and other abnormalities related to this metabolic disorder. Thus, the present study may support the traditional use of H. abyssinica for diabetes mellitus treatment.

Evaluation of hypoglycemic, antihyperglycemic and antihyperlipidemic activities of 80% methanolic seed extract of Calpurnia aurea (Ait.) Benth. (Fabaceae) in mice

Background

Diabetes mellitus is one of the most common chronic health problems in the world. As currently available antidiabetic medications have limitations in terms of safety, efficacy, and cost, it is an important research area to investigate medicinal plants for new antidiabetic compounds that can lead to effective, safe and less costly pharmacotherapy. The present study was done to evaluate the antidiabetic and antidyslipidemic activities of 80% methanolic seed extract of Calpurnia aurea (Ait.) Benth. (Fabaceae) in mice.

Methods

Blood glucose lowering activity of three doses (2.75 mg/kg, 5.5 mg/kg and 11 mg/kg) of the hydromethanolic seed extract of Calpurnia aurea was studied in three animal models: normoglycemic mice, oral glucose-loaded mice, and streptozotocin-induced diabetic mice. Additionally, the effect of the seed extract on body weight and serum lipid profile was studied in the streptozotocin-induced diabetic mice. Glibenclamide (5 mg/kg) was used as a standard drug in all animal models of the study. Blood glucose level was measured using a glucose meter, whereas serum lipid level was measured using an automated chemistry analyzer. Data were analyzed using one-way analysis of variance followed by Tukey's post hoc multiple comparison test.

Results

Hydromethanolic extract of C. aurea seeds showed blood glucose lowering activity in all animal models, and it improved body weight loss and diabetic dyslipidemia in diabetic mice after 14 days of treatment.

Conclusion

This study revealed that hydromethanolic extract of Calpurnia aurea seeds has significant hypoglycemic, antihyperglycemic and antihyperlipidemic activities.

Evaluation of in vivo antidiabetic, antidyslipidemic, and in vitro antioxidant activities of hydromethanolic root extract of Datura stramonium L. (Solanaceae)

BACKGROUND

The global morbidity and mortality rates of diabetes mellitus are persistently increasing. There is a demand for new antidiabetic drugs because the safety and efficacy of currently available medications are limited. The present study was therefore conducted to study the antidiabetic activities of the hydromethanolic root extract of Datura stramonium L. (Solanaceae) in mice.

METHODS

Blood glucose lowering activity of three doses (100, 200, and 400 mg/kg) of the hydromethanolic root extract of D. stramonium was tested on normoglycemic, oral glucose-loaded, and streptozotocin (STZ)-induced diabetic mice models. The effect of the extract on body weight and diabetic dyslipidemia was also studied on STZ-induced diabetic mice. Additionally, antioxidant activity of the plant extract was determined using 2,2-diphenyl-1-picrylhydrazine free radical scavenging assay. Data were analyzed using one way ANOVA followed by Tukey's post hoc multiple comparison test.

RESULTS

The hydromethanolic root extract did not show significant hypoglycemic activity in normoglycemic mice. The plant extract at doses of 100, 200, and 400 mg/kg significantly (P<0.05) reduced blood glucose levels of oral glucose-loaded and diabetic mice. All the three doses of the root extract significantly improved diabetic dyslipidemia and the body weight of diabetic mice. Free radical scavenging activity of the root extract was found to be comparable to ascorbic acid with an IC50 of 13.47 µg/mL.

CONCLUSION

This study demonstrated that the hydromethanolic root extract of D. stramonium possesses significant antidiabetic, antidyslipidemic, and antioxidant activities.

Antidiabetic and Antihyperlipidemic Activities of the Leaf Latex Extract of Aloe megalacantha Baker (Aloaceae) in Streptozotocin-Induced Diabetic Model

BACKGROUND

Diabetes mellitus has become a major public health and economic problem across the globe. The inadequacies, as well as serious adverse effects associated with conventional medicines, led to a determined search for alternative natural therapeutic agents. The leaf latex extract of Aloe megalacantha has been used for the management of diabetes mellitus in Ethiopian folk medicine. This study aimed to evaluate the antidiabetic and antihyperlipidemic effects of the leaf latex extract of A. megalacantha in streptozotocin- (STZ-) induced diabetic model.

METHODS

The experimental diabetes was induced in Swiss albino mice by the administration of a single dose of STZ (150 mg/kg), intraperitoneally. The leaf latex extract of A. megalacantha at three different doses (100, 200, and 400 mg/kg) was administered for a period of 14 days. Fasting blood glucose levels (BGLs) were measured by glucose-oxidase and peroxidase reactive strips. After fourteen days, mice from all groups fasted and the blood was collected through puncturing the retroorbit of the eyes under mild anesthetic condition. The collected blood sample was used to determine serum biochemical parameters such as total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), very low-density lipoprotein (VLDL), and high-density lipoprotein (HDL) cholesterol. The statistical analysis of results was carried out using one-way analysis (ANOVA) followed by post hoc multiple comparison tests.

RESULTS

Oral administration of A. megalacantha leaf latex extract at doses of 100, 200, and 400 mg/kg daily for 14 days results in a significant (p < 0.05) decrease in fasting BGL as compared to negative control STZ-induced diabetic mice. The leaf latex has significantly reduced the level of TC, TG, and LDL, VLDL cholesterol while a significant (p < 0.05) HDL cholesterol increment was observed.

CONCLUSIONS

The findings of the present investigation indicated that the leaf latex of A. megalacantha possessed significant antihyperglycemic and antihyperlipidemic potential which may prove the claimed use of the plant in amelioration of diabetes and associated complications in Ethiopian folk medicine.

Antidiabetic Activities of Hydromethanolic Leaf Extract of Calpurnia aurea (Ait.) Benth. Subspecies aurea (Fabaceae) in Mice

Diabetes mellitus is one of the largest global health problems demanding preventive and new therapeutic interventions. Currently, there is a need for safe, effective, and less costly antidiabetic medications, and investigating medicinal plants for new antidiabetic medication is an interesting research area. Thus, the present study was done to evaluate the antidiabetic activities of 80% methanolic leaf extract of Calpurnia aurea (Ait.) Benth. subspecies aurea (Fabaceae) in mice. Hypoglycemic and antihyperglycemic activity of the three doses (100mg/kg, 200 mg/kg, and 400 mg/kg) of crude hydromethanolic leaf extract was studied on normoglycemic, oral glucose loaded, and streptozotocin-induced diabetic mice models. The effect of the extract on body weight and diabetic dyslipidemia was also studied on streptozotocin-induced diabetic mice. Glibenclamide (5 mg/kg) was used as a standard drug in all cases. A glucose meter and an automated chemistry analyzer were used to measure blood glucose and serum lipid level respectively. Data were analyzed using one-way analysis of variance followed by Tukey's post hoc multiple comparison test. All the three doses of the plant extract (100mg/kg, 200 mg/kg, and 400 mg/kg) showed a significant (p<0.05) antihyperglycemic activity in the diabetic mice at the 7th and 14th day of repeated daily dose administration as compared to the negative diabetic control. But, the extract did not show significant blood glucose lowering activity in normoglycemic, oral glucose loaded, and diabetic mice after single dose administration, and it did not significantly improve the body weight loss and diabetic dyslipidemia of diabetic mice after repeated daily dose administration for 14 days. This study revealed that the hydromethanolic extract of Calpurnia aurea leaves possesses significant antihyperglycemic activity justifying the traditional use of the plant for diabetes.

Prevalence and correlates of herbal medicine use among type 2 diabetic patients in Teaching Hospital in Ethiopia: a cross-sectional study

BACKGROUND

Type 2 Diabetes Mellitus (T2DM) patients are increasingly using herbal remedies due to the fact that sticking to the therapeutic regimens is becoming awkward. However, studies towards herbal medicine use by diabetic patients is scarce in Ethiopia. Therefore, the aim of the current study was to explore the prevalence and correlates of herbal medicine use with different sociodemographic variables among type 2 diabetes patients visiting the diabetic follow-up clinic of University of Gondar comprehensive specialized hospital (UOGCSH), Ethiopia.

METHODS

A hospital-based cross sectional study was employed on 387 T2DM patients visiting the diabetes illness follow-up care clinic of UOGCSH from October 1 to November 30, 2016. An interviewer-administered questionnaire regarding the demographic and disease characteristics as well as herbal medicine use was completed by the study subjects. Descriptive, univariate and multivariate logistic regression statistics were performed to determine prevalence and come up with correlates of herbal medicine use.

RESULTS

From 387 participants, 62% were reported to be herbal medicine users. The most prevalent herbal preparations used were Garlic (Allium sativum L.) (41.7%), Giesilla (Caylusea abyssinica (fresen.) (39.6%), Tinjute (Otostegia integrifolia Benth) (27.2%), and Kosso (Hagenia abyssinicaa) (26.9%). Most of herbal medicine users (87.1%) didn't consult their physicians about their herbal medicine use. Families and friends (51.9%) were the frontline sources of information about herbal medicine followed by other DM patients who used herbal medicines (28.9%).

CONCLUSIONS

The present study revealed a high rate of herbal medicine use along with a very low rate use disclosure to the health care professionals. Higher educational status, a family history of DM, duration of T2DM and presence of DM complications were identified to be strong predictors of herbal medicine use. From the stand point of high prevalence and low disclosure rate, it is imperative for health care providers to strongly consult patients regarding herbal medicine use.

Complementary and alternative medicine use among elderly patients living with chronic diseases in a teaching hospital in Ethiopia

BACKGROUND

The use of complementary and alternative medicine (CAM) among patients with chronic diseases has grown rapidly worldwide. Yet, little has been known about CAM use by elderly patients with chronic diseases in Ethiopia. This study aimed at assessing the prevalence and reasons for CAM utilization among elderly patients living with chronic diseases in Ethiopia.

METHODS

An institution-based quantitative cross-sectional survey was conducted among elderly patients with chronic disease attending outpatient ambulatory clinics of University of Gondar referral and teaching hospital (UoGRTH). An interviewer-administered and semi-structured questionnaire were utilized to collect the data.

RESULT

Of the total respondents, 240 (74%) reported the use of CAM, with herbal medicine and spiritual healing being the most commonly utilized CAM modalities (50.4% and 40.8% respectively). Dissatisfaction with conventional therapy (40.8%) and belief in the effectiveness of CAM (30.8%) are the most commonly cited reasons for the use of CAM therapies. Rural residency, higher educational status, higher average monthly income and presence of co-morbidity were positively associated with the use of CAM.

CONCLUSION

This survey revealed a higher rate of CAM use among elderly patients with chronic diseases, along with a very low rate of disclosing their use to their health care providers. Special attention should be given for these patient population due to the potentially harmful interaction of different herbal remedies with the prescribed medications, thereby predisposing the patient to untoward adverse effects and compromised overall health outcome.

Anti-Diabetic Potential of Ocimum gratissimum Leaf Fractions in Fortified Diet-Fed Streptozotocin Treated Rat Model of Type-2 Diabetes

Background: Ocimum gratissimum (OG) is used in the traditional management of diabetes in Nigeria. This study investigated the anti-diabetic potential of OG leaf fractions (OGLF) in a rat model of Type-2 diabetes (T2D). Methods: Methanol crude extract of OG leaf was fractionated with solvents of increasing order of polarity (n-hexane, chloroform, ethyl-acetate, n-butanol and water). The anti-diabetic potential of the fractions was evaluated in vivo. T2D was induced in Albino Wistar rats and treated with OGLF. Results: The T2D rats showed significant elevation in serum levels of fasting blood glucose (FBG), liver and kidney function biomarkers. At 4-week of intervention with OGLF, the untreated diabetic control group maintained severe hyperglycaemia in the presence of 61.7% serum insulin, 17.3% pancreatic β-cell function (HOMA-β) and 51.5% Insulin sensitivity. The glucose tolerance ability was enhanced in the n-butanol-fraction (OGb) treated group. With 74.8% available serum insulin and 38.6% improvement in insulin sensitivity, the OGb treated group had a 63.5% reduction in FBG and it was found to be most effective as it ameliorates a majority of the changes caused in the studied parameters in diabetic rats. Conclusions: The data from this study suggest that OGb fraction is a potential candidate for the development of an effective drug for the management of T2D.

Antidiabetic efficacy of citronellol, a citrus monoterpene by ameliorating the hepatic key enzymes of carbohydrate metabolism in streptozotocin-induced diabetic rats

Diabetes mellitus is a clinically complex disease characterized by chronic hyperglycemia with metabolic disturbances. During diabetes, endogenous hepatic glucose production is increased as a result of impaired activities of the key enzymes of carbohydrate metabolism. The purpose of the present study was to evaluate the antidiabetic efficacy of citronellol, a citrus monoterpene in streptozotocin (STZ)-induced diabetic rats. Diabetes mellitus was induced by a single intraperitoneal injection of STZ (40 mg/kg b.w). STZ induced diabetic rats received citronellol orally at the doses of 25, 50, and 100 mg/kg b.w for 30 days. In this study the levels of plasma glucose, insulin, hemoglobin (Hb), glycated hemoglobin (HbA1C), glycogen, and the activities of carbohydrate metabolic enzymes, liver and kidney markers were evaluated. Oral administration of citronellol (50 mg/kg) for 30 days dose dependently improved the levels of insulin, Hb and hepatic glycogen with significant decrease in glucose and HbA1C levels. The altered activities of carbohydrate metabolic enzymes, hepatic and kidney markers were restored to near normal. Citronellol supplement was found to be effective in preserving the normal histological appearance of hepatic cells and insulin-positive β-cells in STZ-rats. Our results suggest that administration of citronellol attenuates the hyperglycemia in the STZ-induced diabetic rats by ameliorating the key carbohydrate metabolic enzymes and could be developed as a functional and nutraceutical ingredient in combating diabetes mellitus.

Effect of hydroalcoholic leaves extract of Indigofera spicata Forssk. on blood glucose level of normal, glucose loaded and diabetic rodents

BACKGROUND

Diabetes mellitus is found in all parts of the world and is rapidly increasing in its coverage with alarming rate especially in Asia and Africa. Research is increasingly done with the aim of developing a relatively safe and efficacious anti-diabetic plant based products. Parallelly, this investigation was carried out to evaluate the effect of the hydro alcoholic leaves crude extract of Indigofera spicata (ISP) on the blood glucose level(BGL) of normoglycemic, oral glucose loaded and alloxan induced diabetic rodents.

METHODS

The animals were randomly divided into five groups (n = 6) for all the aforementioned three models. In all models, group-I mice provided 2%tween-80, group-II were treated with 5 mg/kg glibenclamide and the remaining three groups (III, IV & V) were treated with 100, 200, and 400 mg/kg dose of the extract respectively. Statistical significance of differences in BGLs within and between groups was analyzed by SPSS version-21 using one way ANOVA followed by Tukey's post hoc multiple comparison.

RESULT

200 mg/kg and 400 mg/kg extract treated groups of normoglycemic mice showed significant (p < 0.05) BGL reduction compared to the pre-exposure level. In case of OGTT model BGL reduction was statistically significant (p < 0.05) in only 400 mg/kg exposed groups at the 120 min of post-exposure compared to the initial level. However, the BGL reducing effect of doses of the extract at the 4(th), 6(th) and 10(th) hours of post treatment on diabetic mice was found statistically significant compared to both the negative control (p < 0.001) and their respective pretreatment levels (p < 0.05).

CONCLUSION

As it is claimed in ethnobotanical studies, the hydroalcoholic crude extract of ISP leaves have shown prominent anti-diabetic effect and can be therefore used as a good insight for new anti-diabetic drug source with a call for further studies.

In vitro antibacterial activities of compounds isolated from roots of Caylusea abyssinica

BACKGROUND

Caylusea absyssinica, a plant used as vegetable and for medicinal purposes was selected for in vitro antibacterial evaluation in this study. The main aim of this study was to isolate compounds from the plant roots and evaluate their antibacterial activities on clinical bacterial test strains.

METHODS

Compounds from roots of Caylusea absyssinica (fresen) were identified based on observed spectral (1H-NMR, 13C-NMR and IR) data and physical properties (melting point) as well as reported literature. Disk diffusion method was employed to evaluate the antibacterial activities of the isolated compounds on four test bacterial strains namely, Staphylococcus aureus (ATCC25903), Escherichia coli (ATCC25722), Pseudomonas aeruginosa (DSMZ1117) and Salmonella thyphimurium (ATCC13311).

RESULTS

Two compounds, CA1 and CA2 were isolated from the methanol crude extract of the roots of Caylusea absyssinica (fresen). The compounds were identified as β-sitosterol and stigmasterol, respectively. Evaluation of antibacterial activities revealed that the compounds are active against all the bacterial strains in the experiment, showing inhibition zones ranging from 12 mm-15 mm by CA1 and 11 mm-18 mm by CA2 against the different test strains. However, the compounds were less active than the reference drug (Gentamycine), which showed minimum inhibition zone of 21 mm (Pseudomonas aeruginosa) and maximum of 28 mm (Escherichia coli) inhibition zone.

DISCUSSION AND CONCLUSION

The isolation of the compounds is the first report from roots of Caylusea abyssinica and could be potential candidates for future antibacterial drug development programs.

Methanolic leaf exctract of Otostegia integrifolia Benth reduces blood glucose levels in diabetic, glucose loaded and normal rodents

Background

Although the leaves of Otostegia integrifolia traditionally claimed in Ethiopian folklore medicine for management of diabetes mellitus, it has not been validated. The aim of this study was therefore to investigate the antidiabetic activity of Otostegia integrifolia in rodents.

Methods

Male rats or mice were randomly divided into five groups for diabetic, hypoglycemic and glucose tolerance test (OGTT) studies. In all models, group I received Tween 80, 2% v/v, Group II (GL5) treated with 5 mg/kg of glibenclamide and the remaining group: III, IV and V were given the plant extract at doses of 100 mg/kg 200 mg/kg and 400 mg/kg respectively. Blood glucose levels (BGL) were measured by collecting blood samples at different time points. Data was analyzed using one way ANOVA followed by Dunnet’s post hoc test to carry out between and within group comparisons. P < 0.05 was considered as statistically significant.

Results

Inter-group analysis revealed that O. integrifolia at 100 mg/kg and 200 mg/kg reduced the 4^th hour fasting blood BGL significantly (p < 0.001) compared to the control group. The intra-group analysis result has shown O. integrifolia at 200 mg/kg produced a significant (p < 0.05) reduction in BGL at the 1^st, 2^nd, 3rd and 4th hours of post treatment compared to their respective initial levels. Moreover, in the hypoglycemic and OGTT models, O. integrifolia extract at 200 mg/kg, has shown a significant reduction in blood glucose levels compared to negative controls and across all time points.

Conclusion

The crude extract of O. integrifolia has shown significant antidiabetic, hypoglyceamic and oral glucose tolerating effects. The effective dose of the extract was found to be 200 mg/kg in time dependent manner.

Anti-diabetic effects of the acetone fraction of Senna singueana stem bark in a type 2 diabetes rat model

ETHNOPHARMACOLOGICAL RELEVANCE

Senna singueana is currently used in the traditional treatment of diabetes mellitus in Nigeria. The present study examined the anti-diabetic activity of the Senna singueana acetone fraction (SSAF) of stem bark in a type 2 diabetes (T2D) rat model.

MATERIALS AND METHODS

Crude ethyl acetate extract of the Senna singueana stem bark was fractionated with various solvents and the acetone fraction was selected for in vivo studies based on the high α-glucosidase and α-amylase inhibitory activities. In the in vivo study, male Sprague-Dawley rats were induced with T2D and treated with the SSAF at 150 and 300 mg/kg body weight. Several T2D-related parameters were measured in the study.

RESULTS

After 4 weeks of intervention, non-fasting blood glucose concentrations were significantly decreased and the glucose tolerance ability was significantly improved in the SSAF treated groups compared to the diabetic control group. Serum insulin concentrations, pancreatic β-cell function (HOMA-β) and liver glycogen were significantly (P<0.05) increased while serum alanine transaminase, alkaline phosphatase and urea were significantly decreased in the SSAF treated diabetic rats compared to the diabetic control group. Though insignificantly (P>0.05), other T2D-induced abnormalities such as food and fluid intake, body weight, serum lipids, serum fructosamine level and peripheral insulin resistance (HOMA-IR) were also partially ameliorated by the SSAF treatment.

CONCLUSION

Data of this study suggest that orally administered SSAF could ameliorate most of the T2D-induced abnormalities in a T2D model of rats.