Terminalia bellirica stimulates the secretion and action of insulin and inhibits starch digestion and protein glycation in vitro

Cold maceration extraction of wild fruit Terminalia bellirica (Gaertn.) Roxb.: exploring its bioactives for biomedical applications

Terminalia bellirica (T. bellirica) (Gaertn.) Roxb. is a well-known traditional medicinal plants that show promising treatment because of fewer side effects in humans. In the present study, the total phenol, flavonoid, condensed and hydrolyzable tannins extracted and analyzed from cold macerated (CM) T. bellirica (Gaertn.) Roxb. fruit (TBF) and leaves (TBL) extract with the identification of bioactive compounds using GC-MS/MS technique. The highest amount of bioactive content was found in ethanolic extract than toluene. Current experimental data of TBF extract shows the maximum and significant biological activity like free radical scavenging activity against DPPH and FRAP assays with IC50 values of 51.07 ± 0.52 μg/ml and 63.14 ± 0.59 μg/ml respectively. However, IC50 cytotoxicity values of TBF extract on MCF-7 cells for 24 hrs was found to be 6.34 ± 0.72 μg/ml. Minimum inhibitory concentration (MIC) for infectious pathogens Escherichia coli and Bacillus cereus was >12.5 μg/ml and >100 μg/ml respectively, however, anti-inflammatory activity was demonstrated as an IC50 value of 509.1 ± 1.72 μg/ml. Cold macerated fruit extract revealed threatening inhibitory potential against the α-amylase and α-glucosidase enzymes, with IC50 of 50.98 ± 0.23 μg/ml and 46.70 ± 1.38 μg/ml respectively. Finally, the outcome of this study showed that T. bellirica (Gaertn.) Roxb. fruit extract could be an effective source of bioactives with efficient biomedical properties.

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

OBJECTIVE

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

METHODS

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

KEY FINDINGS

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

CONCLUSIONS

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

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

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

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

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

Potential effect of tropical fruits Phyllanthus emblica L. for the prevention and management of type 2 diabetic complications: a systematic review of recent advances

Phyllanthus emblica is a fruit widely consumed in subtropical areas, which is rich in polyphenols and other nutrients. There are increasing evidences that as a daily and nutritious fruit, it may have a positive role in controlling diabetic complications. According to the new study, its mechanisms include enhancing the functioning of insulin, reducing insulin resistance, activating the insulin-signaling pathway, protecting β-cells, scavenging free radicals, alleviating inflammatory reactions, and reducing the accumulation of advanced glycation end products. Owing to its few side effects, and low price, it should be easily accepted by patients and has potential for preventing diabetes. Taken together, Phyllanthus emblica may be an ideal fruit for controlling diabetic complications. This review highlights the latest findings of the role of Phyllanthus emblica in anti-diabetes and its complications, especially clarifies the molecular mechanism of the chemical components related to this effect, and prospects some existing problems and future research directions.

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

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

Medicinal plants utilized in Thai Traditional Medicine for diabetes treatment: Ethnobotanical surveys, scientific evidence and phytochemicals

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetes mellitus remains the most lethal metabolic disease of contemporaneous times and despite the therapeutic arsenal currently available, research on new antidiabetic agents remains a priority. In recent years, the revitalization of Thai Traditional Medicine (TTM) became a clear priority for the Thai government, and many efforts have been undertaken to accelerate research on herbal medicines and their use in medical services in various hospitals. Additionally, and particularly in rural areas, treatment of diabetes and associated symptomatology frequently relies on herbal preparations recommended by practitioners of TTM. In the current work, medicinal plants used in Thailand for treating diabetes, as well as their hypoglycaemic pharmacological evidences and potential therapeutic use for diabetes-related complications were reviewed.

MATERIALS AND METHODS

Ethnopharmacological information on the plant materials used in TTM for diabetes treatment was collected through literature search in a range of scientific databases using the search terms: diabetes, folk medicine, Thailand medicinal plants, traditional medicine. Information regarding scientific evidence on the antidiabetic effects of surveyed species was obtained considering not only the most common taxonomic designation, but also taxonomic synonyms, and including the keywords 'diabetes' and 'hypoglycaemic effect'.

RESULTS

A total of 183 species known to be used for diabetes management in TTM were reviewed, with 30% of them still lacking experimental evidences to support claims regarding the mechanisms and phytochemicals underlying their antidiabetic properties. Moreover, a total of 46 bioactives displaying effective antidiabetic effects have been isolated from 24 species, their underlying mechanism(s) of action being fully or partially disclosed.

CONCLUSIONS

We deliver the most extensive survey dealing with the ethnomedicinal knowledge of Thai medicinal plants utilized on diabetes management. We are certain that the current review will spark further research on Thai plants for the development of new standardized phytomedicines through drug discovery programmes.

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

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

Terminalia bellirica (Gaertn.) roxb. (Bahera) in health and disease: A systematic and comprehensive review

BACKGROUND

Terminalia bellirica (Gaertn.) Roxb. is one of the oldest medicinal herbs of India, Pakistan, Nepal, Bangladesh and Sri Lanka as well as South-East Asia. Its medicinal utility has been described in the different traditional medicinal systems, such as Ayurveda, Unani, Siddha, and traditional Chinese medicine.

PURPOSE

The present study is aimed at providing a comprehensive overview on the traditional medicinal use, major phytoconstituents, biological and pharmacological activities and related mechanisms of actions and clinical studies of T. bellirica. Another objective is to describe current limitations and future direction of T. bellirica-related research.

METHODS

PubMed, ScienceDirect, Scopus, Cochrane Library, and EBOSCO host databases were selected to explore literature published between 1980 and 2020 (till March). Keywords used in various combinations comprised of Terminalia bellirica, phytoconstituents, health effects, pharmacological activities, molecular targets, in vitro, in vivo, clinical studies, and disease prevention.

RESULTS

A broad spectrum in vitro and in vivo studies suggested various biological and pharmacological effects, including antioxidant, anti-inflammatory, immunomodulatory, antimicrobial, hepatoprotective, renoprotective, antidiabetic, anti-hyperlipidemic, and anticancer activities. Diverse bioactivities of T. bellirica have been ascribed to the presence of many bioactive phytochemicals, such as glucoside, tannins, gallic acid, corilagin, ellagic acid, ethyl gallate, galloyl glucose, chebulagic acid, and arjunolic acid.

CONCLUSION

Preclinical and clinical studies have suggested that T. bellirica plant and its phytoconstituents have immense potential for prevention and treatment of various diseases. Additional in vivo studies and clinical trials are warranted to realize the complete medicinal attributes of this plant.

Ethnomedicinal Investigation of Medicinal Plants of Chakrata Region (Uttarakhand) Used in the Traditional Medicine for Diabetes by Jaunsari Tribe

The Himalayan region is the treasure house of natural wealth, particularly of medicinal and aromatic plants. These plants are used by the Indian traditional healers for the past many centuries to treat various ailments such as skin disorders, asthma, diabetes, snake bite, fever, pain, eye diseases, diarrhoea, indigestion, jaundice, burn, wound, liver disorder, CNS disorders and urinary tract infection. The indigenous traditional knowledge of medicinal plants and therapies of various local communities has been lost due to changes in traditional culture and the introduction of modern technologies. Therefore, it is essential to explore the traditional knowledge of the indigenous medicinal plants mainly in such areas where there is a severe threat to natural vegetation owing to human inhabitation. The present study aimed to explore the medicinal plants of Chakrata region (Jaunsar-Bawar Hills), Uttarakhand, India used in the folk medicine for the management of diabetes by Jaunsari Tribe. In a comprehensive field survey, the information about the medicinal plants have been mainly collected from the traditional healers and other elderly people belong to the tribal community. All the information about the medicinal plants of the study area was documented in a field book. Various tools have been used to collect the samples for identification purpose and the authentication of the plants was done with the help of taxonomists. The literature on these plants was also searched from online (PubMed and Scopus) as well as from some textbooks and Ayurvedic classical texts. The present survey-based work described a total of 54 plants belonging to 47 genera and 30 families used in the traditional medicine for the management of diabetes in Chakrata region. The information gathered from the local community revealed that the plants are effective in diabetes and one can use most of them without consulting a practitioner or traditional healer. The literature revealed that most of the surveyed plants are already used in the preparation of various antidiabetic formulations such as Chandraprabha vati, Nishamalaki chunra, Amritamehari churna and Nisakathakadi kashayam along with various patent drugs which are frequently prescribed by the Ayurvedic practitioners in India. The present study explored the traditional as well as scientific knowledge on the antidiabetic plants used by the tribal community. The documented information on these plants can be further used by the scientific community to develop new drugs/formulations with the help of modern techniques.

Uncovering potential of Indonesian medicinal plants on glucose uptake enhancement and lipid suppression in 3T3-L1 adipocytes

ETHNOPHARMACOLOGICAL RELEVANCE

As obesity is a key factor in the development of type 2 diabetes, lowering lipid accumulation in adipose tissues is as important as increasing insulin sensitivity in diabetic patients. The selected plant extracts used in this screen have been traditionally used in Indonesian medicine for the treatment of diabetes and its complications.

AIM OF THE STUDY

To investigate the ability of the selected plants to both increase insulin sensitivity through the enhancement of glucose uptake after insulin induction in adipocytes and suppress lipid production in the same target cells.

MATERIALS AND METHODS

Dried Indonesian medicinal plants were extracted with 50% (v/v) aq. methanol. The extracts were dissolved in 50% DMSO when tested in 3T3-L1 adipocytes. The screening platform consists of insulin-induced glucose uptake, lipid accumulation, and cell viability. Initially, an enzymatic fluorescence assay was designed to demonstrate the enhancement of 2-deoxyglucose (2-DG) uptake after insulin induction. Different concentrations of the extracts that enhanced glucose uptake were subjected to lipid accumulation assay using Oil Red O staining. Potential extracts based on lipid suppression were subsequently assessed by CCK-8 cell viability assay to distinguish lipid reduction activity from cytotoxicity.

RESULTS

Out of 59 plants, 13 plants demonstrated their ability to increase glucose uptake in 3T3-L1 adipocytes after insulin induction, and 4 of these plants' extracts suppressed lipid production of the cells. The CCK-8 assay results of those 4 plant extracts suggest that the lipid inhibition activity of Eurycoma longifolia Jack (root) and Piper nigrum L. (fruits) extracts is not attributed to their cytotoxicity in the adipose cells. Both of the plant extracts increased glucose uptake by more than 200% at 50 μg/mL and suppressed lipid accumulation in a concentration-dependent manner.

CONCLUSIONS

Screening of selected Indonesian medicinal plants has uncovered the potentials of E. longifolia Jack (root) and P. nigrum L. (fruits) with dual active functions, increasing insulin sensitivity through the enhancement of glucose uptake and reducing lipid accumulation in adipose cells. These findings suggest that the ability of both plants to suppress lipid production would provide additional benefits in the treatment of diabetes.

Aqueous extract of some indigenous medicinal plants inhibits glycation at multiple stages and protects erythrocytes from oxidative damage-an in vitro study

Azadirachta indica, Emblica officinalis, Syzygium cumini and Terminalia bellirica are common in Indian system of traditional medicine for the prevention of diabetes and its complications. The aim of the present study was to comprehensively and comparatively investigate the antiglycation potential of these plant extracts at multiple stages and their possible protective effect against glycated albumin mediated toxicity to erythrocytes. Antiglycation activities of these plant extracts was measured by co-incubation of plant extract with bovine serum albumin-fructose glycation model. The multistage glycation markers- fructosamines (early stage), protein carbonyls (intermediate stage) and AGEs (late stage) are investigated along with measurement of thiols and β aggregation of albumin using amyloid-specific dyes-Congo red and Th T. Protection of erythrocytes from glycated albumin induced toxicity by these plant extracts was assessed by measuring erythrocytes hemolysis, lipid peroxidation, reduced glutathione and intracellular antioxidant capacity. Total phenolics, reducing power and antioxidant activities of the plant extracts were also measured. In vitro glycation assays showed that plant extracts exerted site specific inhibitory effects at multiple stages, with T. bellirica showing maximum attenuation. In erythrocytes, along with the retardation of glycated albumin induced hemolysis and lipid-peroxidation, T. bellirica considerably maintained cellular antioxidant potential. Significant positive correlations were observed between erythrocyte protection parameters with total phenolics. These plant extracts especially T. bellirica prevents glycation induced albumin modifications and subsequent toxicity to erythrocytes which might offer additional protection against diabetic vascular complications.

Red Liriope platyphylla stimulated the insulin secretion through the regulation of calcium concentration in rat insulinoma cells and animal models

The aim of this study was to investigate the effects of Red L. platyphylla (RLP) on calcium and glucose levels during insulin secretion. To achieve this, alteration of insulin and calcium concentrations was measured in rat insulinoma-1 (INS-1) cells and animal models in response to RLP treatment. In INS-1 cells, maximum secretion of insulin was detected upon treatment with 200 µg/mL of RLP for 20 min. Nifedipine, an L-type calcium channel blocker, effectively inhibited insulin secretion from INS-1 cells. Regarding calcium levels, the maximum concentration of intracellular calcium in INS-1 cells was obtained by treatment with 100 µg/mL of RLP, whereas this level was reduced under conditions of 200 µg/mL of RLP. Further, RLP-treated INS-1 cells showed a higher level of intracellular calcium than that of L. platyphylla (LP), Korea White Ginseng (KWG), or Korea Red Ginseng (KRG)-treated cells. This RLP-induced increase in intracellular calcium was abrogated but not completely abolished upon treatment with 40 µM nifedipine in a dose-dependent manner. Furthermore, the insulin level was dramatically elevated upon co-treatment with high concentrations of glucose and RLP, whereas it was maintained at a low level in response to glucose and RLP co-treatment at low concentrations. In an animal experiment, the serum concentration of calcium increased or decreased upon RLP treatment according to glucose level compared to vehicle treatment. Therefore, these results suggest that insulin secretion induced by RLP treatment may be tightly correlated with calcium regulation, which suggests RLP is an excellent candidate for diabetes treatment.

Therapeutic potential of octyl gallate isolated from fruits of Terminalia bellerica in streptozotocin-induced diabetic rats

CONTEXT

Medicinal plants are a potential source of antidiabetic drugs. Terminalia bellerica Roxb. (Combretaceae) is used in Indian traditional systems of medicine to treat diabetes mellitus.

OBJECTIVE

The aim of this study was to isolate and identify antihyperglycemic principle(s) from the fruits of T. bellerica and assess the bioactivity in streptozotocin (STZ)-induced diabetic rats.

MATERIALS AND METHODS

Bioassay-guided fractionation was followed to isolate the active compound(s), structure was elucidated using (1)H and (13)C NMR, IR and mass spectrometry and administered intragastrically to diabetic Wistar rats at different doses (5, 10 and 20 mg/kg, body weight) for 28 d. Plasma glucose, insulin, C-peptide and other biochemical parameters were studied.

RESULTS

Octyl gallate (OG) isolated first time from the fruit rind of T. bellerica significantly (p < 0.05) reduced plasma glucose to near normal values (108.47 ± 6.9 mg/dl) after 14 d at the dose of 20 mg/kg. In addition, OG significantly increased plasma insulin, C-peptide, total protein, albumin, tissue glycogen, body weight and markedly decreased serum total cholesterol, triglyceride, LDL-cholesterol, urea, uric acid and creatinine in diabetic rats. Also OG restored the altered regulatory enzymes of carbohydrate metabolism.

DISCUSSION AND CONCLUSION

OG might have augmented the secretion of insulin by the modulation of cAMP and intracellular calcium levels in the β cells of the pancreas. Our findings indicate that OG isolated first time from the fruit rind of T. bellerica has potential antidiabetic effect as it augments insulin secretion and normalizes the altered biochemical parameters in experimental diabetic rat models.

Inhibitory activities of Ulva lactuca polysaccharides on digestive enzymes related to diabetes and obesity

The aim of this study was to evaluate the effect of alga Ulva lactuca polysaccharides (ULPS) on key enzymes related to diabetes and obesity. This marine natural product, ULPS, exerted potential inhibition on key enzymes related to starch digestion and absorption in both plasma and small intestine mainly α-amylase by 53% and 34% and maltase by 97 and 164% respectively, leading to a significant decrease in blood glucose rate by 297%. Moreover, ULPS potentially inhibited key enzymes of lipid metabolism and absorption as lipase activity in both plasma and small intestine by 235 and 287% respectively, which led to a notable decrease of blood LDL-cholesterol and triglycerides levels, and in the counterpart an increase in HDL-cholesterol level in surviving diabetic rats. Additively, ULPS significantly protected the liver-kidney functions, by decreasing of aspartate transaminase (AST), alanine transaminase (ALT) and gamma-glytamyl transpeptidase (GGT) activities and creatinine, urea and albumin rates in plasma.