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

Hepatoprotective effect of hydromethanol extract of Otostegia integrifolia benth leaves in isoniazid and rifampicin induced Swiss albino mice

Introduction

Drug-induced liver injury is the most common cause of acute liver failure. Off-Target effect "hepatotoxicity "frequently detected during clinical examination of patients on anti-Tb medication particularly isoniazid (INH), and rifampin (RMP). However, there is no any treatment option against isoniazid and rifampicin induced hepatotoxicity. It is, therefore, necessary to search for effective affordable and safe drugs from medicinal plants for the prevention of liver toxicity caused by isoniazid and rifampicin. The aim the current study is to evaluate hepatoprotective effect of hydro methanol extract from Otostegia integrifolia leaves in isoniazid and rifampicin-induced hepatotoxicity in Swiss albino mice.

Methods

O. integrifolia leaves powder was macerated in hydromethanol and thirty Swiss albino mice 29.0-40.6 g were grouped in to five groups. Group I were given 20 ml/kg distilled water, group II were given 100 mg INH and 150 mg RIF per kg body weight. Group III, group IV, and group V were given 200 mg extract, 400 mg extract, and 100 mg of N-acetyl cysteine respectively per kg 1hr before induction with 100 mg INH plus 150 mg RIF per kg. The treatments were followed for 14 days. On the 15th day, all mice were anaesthetized with diethyl ether; blood samples were collected for the assessment liver enzyme and function test.

Results

Group II mice's serum ALT, AST and total bilirubin levels were significantly increased and serum total protein and albumin levels were significantly decreased as compared with group I mice. The groups of mice treated with O. integrifolia at a dose of 400 mg/kg and N-acetyl cysteine AST, ALT and total bilirubin level were significantly decreased; and total protein and albumin levels were significantly (P < 0.05) increased as compared with group II. The liver index of the group IV showed decreased (P < 0.05) as compared to the group II.

Conclusion

Evidence from our study revealed that the hydromethanol extract of O. integrifolia has a hepatoprotective effect against isoniazid and rifampicin-induced hepatotoxicity in Swiss Albino mice. This protective effect of O. integrifolia extract may be based on its metal ion reducing power, free radical scavenging activity, and anti-inflammatory activity and could be used as a potential therapeutic option.

Oral empagliflozin-loaded tri-layer core-sheath fibers fabricated using tri-axial electrospinning: Enhanced in vitro and in vivo antidiabetic performance

Empagliflozin (EM) was successfully loaded in polycaprolactone/poly (L-lactic acid)/polymethyl methacrylate (PCL/PLA/PMMA) fibers. In the rat β-cell line (BRIN-BD11), the insulin expression ratio of pancreatic β-cells was stimulated at high and low glucose by culturing with tri-layer EM-loaded fiber (EMF) for 48 h. The expression ratios of glucokinase and GLUT-2 proteins increased after EMF treatment. According to the in vitro drug release test, 97% of all drug contained in fibers was released in a controlled manner for 24 h. The pharmacokinetic test revealed that the bioavailability was improved ∼4.8-fold with EMF treatment compared to EM-powder and blood glucose level was effectively controlled for 24 h with EMF. Oral administration of EMF exhibited a better sustainable anti-diabetic activity even in the half-dosage than EM-powder in streptozotocin/nicotinamide-induced T2DM rats. The levels of GLP-1, PPAR-γ, and insulin were increased while the levels of SGLT-2 and TNF-α were decreased with EMF treatment. Also, EMF recovered the histopathological changes in the liver, pancreas, and kidney in T2DM rats and protected pancreatic β-cells. Consequently, EMF is suggested as an unprecedented and promotive treatment approach for T2DM with a higher bioavailability and better antidiabetic effect compared to conventional dosage forms.

Anti-Diabetic Activities of Hydro-Methanolic Crude Extract and Solvent Fractions of Heteromorpha arborescens (Apiaceae) Leaves in Mice

Background

Heteromorpha arborescens has been used to treat diabetes traditionally. There was no in vivo study to support the claim. This study aimed to confirm anti-diabetic activity of 80% methanol in water extract and solvent fractions of H. arborescens leaves in mice.

Methods

H. arborescens leaves were macerated and extracted in 80% methanol in water. Hydro-methanol extract of H. arborescens leaves were tested in mice models. 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 each comprised six mice: diabetic negative control and normal negative control groups treated with 10 mL/kg distilled water, diabetic positive control group treated with Glibenclamide 5 mg/kg and three diabetic tested groups treated with extract at 100, 200, and 400 mg/kg doses. A one-way ANOVA was performed to analyze the data, and the post hoc Tukey's test was utilized for multiple comparisons. The P-value <0.05 was considered statistically significant.

Results

Hydro-methanol extract of H. arborescens leaves at 400 mg/kg in normoglycemic mice significantly lowered blood glucose levels (BGLs) (P< 0.01). Mice with oral glucose-loaded test lowered BGLs at dosages of 200 mg/kg (P < 0.05) and 400 mg/kg (P < 0.01) respectively. Single-dose of ethyl acetate, n-hexane fractions and hydro-methanol extract at 100 mg/kg, 400 mg/kg and 200 mg/kg reduced BGLs (P < 0.05, P < 0.001, and P < 0.01) respectively. BGL drops in diabetic mice given daily repeated doses of 200 mg/kg of hydro-methanol extract and 400 mg/kg of ethyl acetate fraction (P < 0.001). Diabetic mice gained weight at a 400 mg/kg hydro-methanol extract and ethyl acetate fraction (P < 0.05 and P < 0.01) respectively. Hydro-methanol extract and ethyl acetate fraction and at 200 mg/kg decreased total cholesterol, triglycerides, and low-density lipoprotein and increased high-density lipoprotein (P < 0.001).

Conclusion

80% methanol in water extract and solvent fractions of H. arborescens leaves showed anti-diabetic effects and significantly reduced hyperlipidemia in diabetics, this study supported the traditional usage of H. arborescens for treating diabetes; however, species variation could also limit such a straightforward extrapolation of the findings of this study in humans.

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.

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.

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.

Methanol (80%) leaf extract of Otostegia integrifolia Benth (Lamiaceae) lowers blood pressure in rats through interference with calcium conductance

Background

Otostegia integrifolia Benth. (Lamiaceae) leaves are used to treat hypertension in Ethiopian folk medicine. However, the claim has so far not been investigated scientifically. Thus, the objective of this study was to evaluate the antihypertensive activity of 80% methanol leaf extract of O. integrifolia in animal model of hypertension and possible underlying mechanisms in isolated rat aorta.

Methods

Antihypertensive effect of various oral doses of the extract (250, 500 and 1000 mg/kg) was determined in fructose-induced hypertensive rats using the non-invasive tail-cuff method. Thoracic aortic strips of rats were isolated and suspended in organ bath, and the vasodepressor effect as well as the possible mechanism (s) of action were studied by means of isometric tension recording experiments ex vivo. Phytochemical analysis was also performed to suggest possible constituents related to the activity.

Results

Blood pressure was significantly lowered in a dose-dependent manner following extract administration, suggesting that the extract possesses antihypertensive activity. The extract also caused a dose-dependent relaxation of aortic strip precontracted with KCl at a concentration of 6.25–125 μg/L, with a maximum relaxation (100%) achieved at a cumulative concentration of 318.75 μg/ml. The relaxation mechanism was found to be independent of muscarinic receptors, prostanoids, histamine receptors, ATP dependent K⁺ channels, sarcoplasmic reticulum stored Ca²⁺ and the endothelium system. The extract shifted the Ca²⁺ concentration-response curve to the right similar to that caused by nifedipine, suggesting that vasorelaxation could possibly be mediated via calcium channel blockade. The extract was found to contain phenolic compounds (164.3 mg/g, expressed as gallic acid equivalents) and flavonoids (125.7 mg/g, expressed as quercetin equivalents).

Conclusion

The findings revealed that the plant is endowed with antihypertensive activity, providing evidence for its traditional use. The effect maybe, at least in part, due to dilation of blood vessels through blockade of Ca^+ 2 channels mediated by phenolic and flavonoid constituents.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-021-03222-4.

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.

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.

Evaluation of Analgesic and Anti-inflammatory Potential of 80% Methanol Leaf Extract of Otostegia integrifolia Benth (Lamiaceae)

Introduction

Pain and inflammatory disorders are the most prevalent syndromes. Different herbs were used for treatment of pain and inflammation including members of the genus Otostegia. As a result, this research investigated the in vivo analgesic and anti-inflammatory effects of 80% methanol leaf extract of Otostegia integrifolia in mice.

Methods

The analgesic and anti-inflammatory effects of the plant was evaluated using hot plate method, acetic-acid induced writhing test, and carrageenan and formalin induced paw edema. Three experimental groups (100, 200, and 400 mg/kg) received the extract while morphine 10 mg/kg and aspirin 150 mg/kg were used as a positive control for analgesic and anti-inflammatory tests accordingly. Distilled water (10 mL/kg) was used as negative control.

Results

From the experimental groups, OI400 displayed significant analgesic and anti-inflammatory activities (P<0.001). In acetic acid induced writhing tests, the number of writhes decreased significantly (P<0.001) in all experimental groups. Similarly, OI400 reduced the mean paw edema significantly in carrageenan and formalin induced paw edema (P<0.05 and P<0.001, respectively).

Conclusion

In general, the results obtained in this study demonstrated that the extract exhibited significant analgesic and anti-inflammatory potential in mice.

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.

Anil Kumar N, Sharopov F, Ramírez-Alarcón K, Ruiz-Ortega A, Abdulmajid Ayatollahi S, Valere Tsouh Fokou P, Kobarfard F, Amiruddin Zakaria Z, Iriti M, Taheri Y, Martorell M, Sureda A, N. Setzer W, Durazzo A, Lucarini M, Santini A, Capasso R, Adrian Ostrander E, -ur-Rahman A, Iqbal Choudhary M, C. Cho W, Sharifi-Rad J. Antidiabetic Potential of Medicinal Plants and Their Active Components

Diabetes mellitus is one of the major health problems in the world, the incidence and associated mortality are increasing. Inadequate regulation of the blood sugar imposes serious consequences for health. Conventional antidiabetic drugs are effective, however, also with unavoidable side effects. On the other hand, medicinal plants may act as an alternative source of antidiabetic agents. Examples of medicinal plants with antidiabetic potential are described, with focuses on preclinical and clinical studies. The beneficial potential of each plant matrix is given by the combined and concerted action of their profile of biologically active compounds.

The methanolic extract of Thymus praecox subsp. skorpilii var. skorpilii restores glucose homeostasis, ameliorates insulin resistance and improves pancreatic β-cell function on streptozotocin/nicotinamide-induced type 2 diabetic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Thymus praecox subsp. skorpilii var. skorpilii (syn. Thymus praecox subsp. jankae (Celak.) Jalas) is consumed as a Turkish folk medicine for the treatment of spasm, sore throat and shortness of breath, also having strong antioxidant activity and the leaves of the plant have been utilized for the treatment of diabetes as the decoction in Turkey.

AIM OF THE STUDY

In the present study, we aimed to investigate the potential mechanism of antidiabetic action of Thymus praecox subsp. skorpilii var. skorpilii methanolic extract (TPSE) on streptozotocin (STZ)/nicotinamide (NA)-induced type 2 diabetic rats.

MATERIALS AND METHODS

Sprague Dawley rats were randomly divided into four groups; control, diabetes, TPSE (100 mg/kg b.w, p.o.) and metformin group (400 mg/kg b.w, p.o.). Diabetes was established in all groups except control group by 55 mg/kg STZ (i.p.) for once 15 min after 100 mg/kg NA injection. 3 days after STZ/NA injection, treatments were administered for three weeks and then rats were decapitated; tissue and blood samples were obtained for measuring the level of glucose transporters (both GLUTs and sodium glucose co-transporters (SGLTs)), enzymes related to glucose (Hexokinase (HK), phosphoenolpyruvate carboxykinase (PEPCK), α-glucosidase) and lipid metabolism (Acetyl-coenzyme carboxylase (ACC)), AST, ALT, creatinine, insulin, anti-inflammatory (IL-10) and inflammatory (TNF-α, IL-1β, IL-6) cytokines, AMP-activated protein kinase (AMPK), peroxisome proliferator-activated receptor gamma (PPAR-γ) and glucagon like peptide-1 (GLP-1). Histopathological alterations of the pancreas were examined.

RESULTS

After three weeks of treatment, TPSE has exhibited a significant reduction of plasma levels of the proinflammatory cytokines. Besides, TPSE treatment elevated plasma insulin levels and normalized blood glucose levels. Moreover, it improved the values of AMPK in liver and GLP-1 in pancreas. Increased α-glucosidase, PEPCK, GLUT-2 and SGLTs levels with the induction of diabetes considerably lowered with TPSE treatment. Especially on SGLT-2, TPSE achieved a more prominent decrease. After the atrophy in Langerhans islets due to diabetes induction, treatment was found to prevent the damage of islets.

CONCLUSIONS

Based on the findings presented here, it has been concluded that TPSE has marked antidiabetic effects through various pathways on STZ/NA-induced diabetic rats and it may potentially be used as an effective treatment for type 2 diabetes mellitus (T2DM). Further research on isolation of the bioactive components is underway.

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.

Hypoglycemic and hypolipidemic activity of aqueous leaf extract of Passiflora suberosa L

Leaves of Passiflora suberosa L. (Family: Passifloraceae; common name: wild passion fruit, devil's pumpkin) are used in Sri Lankan traditional medicine for treating diabetes. The present study investigated the in vivo ability of P. suberosa leaves to manage blood sugar status and associated cholesterol levels. Mechanisms of action and toxicity were also determined. Phytochemical screening of aqueous extracts of P. suberosa leaves and carbohydrate content of the leaves were determined according to previously published methods. In two group of male mice (n = 9), effects on fasting and random blood glucose levels (BGLs) of different acute doses (0, 25, 50, 100 and 200 mg/kg) of the aqueous leaf extract (ALE) were evaluated at 1, 3, and 5 h post-treatment. In another set of mice, the fasting BGL was evaluated following treatment of 0 or 50 mg/kg ALE (dose prescribed in traditional medicine) for 30 consecutive days. The lipid profile, some mechanism of ALE action (diaphragm glucose uptake, glycogen content in the liver and skeletal muscles) and its toxicity (behavioural observation, food and water intake, hepatoxicity) were also assessed following 30-day treatment. However, sucrose and glucose tolerance tests and intestinal glucose uptake were conducted to determine portion of mechanisms of action following single dose of 50 mg/kg ALE. Phytochemical screening revealed the presence of alkaloids, unsaturated sterols, triterpenes, saponins, flavonoids, tannins and proanthocyanidins. Carbohydrate content of the leaves was 12.97%. The maximum hypoglycemic effect was observed after 4 h of 50 and 100 mg/kg ALE administration. The extract decreased fasting BGL (18%) following an oral sucrose challenge and inhibited (79%) glucose absorption from the intestine. Correspondingly, the levels of glycogen in the liver (61%) and in the skeletal muscles (57%) were found be higher than that of the control group. The levels of total cholesterol (17%) and tri-glyceraldehyde levels (12%) found to be reduced in treated groups. Furthermore, no significant toxic effects were observed in treated groups. The present results suggest that the leaves of P. suberosa can be used to manage blood glucose and cholesterol levels. Isolation of active compounds are recommended for further analysis.

Attenuation of diabetic nephropathy in streptozotocin-induced diabetic rats by Punica granatum Linn. leaves extract

With an objective to develop Complementary and Alternative Medicine for the treatment of diabetic nephropathy, the present study investigated the protective effects of methanolic extract of Punica granatum leaves (MPGL) in streptozotocin-induced diabetic nephropathy. Diabetic nephropathy has become a leading cause of end stage renal failure worldwide. P. granatum, due to its anti-diabetic, anti-inflammatory and antioxidant activities may retard the progression of diabetic nephropathy. In this study, diabetes was induced by a single injection of streptozotocin (STZ, 45 mg/kg, i.p.) in rats. STZ-diabetic rats were treated with oral doses of MPGL (100, 200 and 400 mg/kg) for 8 weeks. At the end of the experimental period, body and kidney weight and blood glucose levels were determined. Serum and urine parameters were investigated. Antioxidant enzymes and lipid peroxide levels were determined in the kidney along with histopathological examination of the same. MPGL significantly increased body weight, lowered blood glucose levels and ameliorated kidney hypertrophy index in the STZ-diabetic rats. The extract also decreased the levels of creatinine, blood urea nitrogen, total cholesterol, triglycerides, advanced glycation end products and albumin in serum and urine, respectively. MPGL significantly increased the antioxidant parameters in the kidney. Histological evaluation revealed that MPGL treated STZ-diabetic rats demonstrated reduced vacuolar degeneration of tubules; periodic acid Schiff base (PAS) positivity staining intensity in glomeruli and basement membrane thickening. Present findings provide experimental evidence that MPGL has potential antioxidant, antihyperglycemic and anti-glycation activities which might be helpful in slowing the progression of diabetic nephropathy.

Hypoglycemic and hypolipidemic activities of aqueous extract of flowers from Nycantus arbor-tristis L. in male mice

BACKGROUND

Boiled aqueous extract of flowers (AEF) from Nyctanthes arbor-tristis L. are used in Sri Lankan traditional Ayruvedic Medicine to manage diabetes mellitus. AEF has widely been used as a folk medicine for the treatment of various ailments due to its therapeutic activity. However, little is known concerning therapeutic activity of the extract as well as its underline mechanisms and safety. Diabetes is known to increase low-density cholesterol and decrease high-density cholesterol thus triggering coronary diseases. Hence, the primary objective of the present study is to investigate the hypoglycemic and hypolipidemic activities of the AEF.

METHODS

AEF was prepared and male mice (n = 9 group) were gavaged either with 250, 500 and 750 mg/kg of AEF or distilled water (DW). Subsequently, fasting and random blood glucose concentrations were determined. To investigate mechanisms of actions of AEF, animals were orally administered with 500 mg/kg or the vehicle (DW) and glucose tolerance was performed before and after glucose challenge. For further studies, in vitro alpha-amylase assay and glucose absorption from the gastrointestinal tract were performed using 500 mg/kg of the extract. Additionally, glycogen content in the liver and skeletal muscles, a complete lipid profile assay, and toxicological and biochemical parameters were conducted after a chronic study.

RESULTS

Five hundred mg/kg and 750 mg/kg of AEF significantly (p < 0.01) reduced fasting blood glucose levels respectively by 49 and 39% at 4 h post-treatment, while 500 mg/kg of AEF also decreased the random blood glucose level significantly (p < 0.01) by 32% at 4 h post-treatment. AEF significantly inhibited glucose absorption by 85% from the intestine and increased diaphragm uptake of glucose by 64%. The extract also exhibited inhibition (16.66%) of alpha-amylase enzyme activity. It also decreased the level of total cholesterol (by 44.8%), triglyceride (by 53%) and increased (by 57%) the high-density lipoprotein cholesterol. Treatment with AEF did not induce any overt signs of toxicity or hepatotoxicity.

CONCLUSION

Results the present study indicated that AEF possess hypoglycemic and hypolipdemic properties. Therefore, AEF could be used as an alternative medicine in management of diabetes mellitus.