Curative Effect of Catechin Isolated from Elaeagnus Umbellata Thunb. Berries for Diabetes and Related Complications in Streptozotocin-Induced Diabetic Rats Model

Review on the Anti-Hyperglycemic Potential of Psidium guajava and Seriphium plumosum L

The treatment and management of diabetes mellitus (DM) with conventional therapies, such as insulin injections and oral hypoglycemic agents, present significant challenges due to their side effects and burdensome administration. Therapies often manage symptoms rather than addressing insulin regulation, akin to medications like thiazolidinediones and glinides, which resemble many medicinal plants. Medicinal plants offer potential alternative treatments due to bioactive compounds targeting diabetes causes. We aimed to explore the antidiabetic potential of two medicinal plants, Psidium guajava and Seriphium plumosum L., by investigating their phytochemical constituents, medicinal uses, pharmacological actions, and mechanisms. This review followed specific guidelines and searched databases including PubMed, Scopus, ScienceDirect, and Web of Science for studies on medicinal plants and DM. Eligible studies underwent quality assessment and were categorized based on their design and interventions for data synthesis. This review identified the phytochemical constituents in Psidium guajava and Seriphium plumosum L., including tannins, flavonoids, phenols, and steroids, exerting antidiabetic effects through various mechanisms like antioxidant activity, anti-inflammatory effects, stimulation of insulin secretion, glucose regulation, and inhibition of carbohydrate-digesting enzymes. Psidium guajava and Seriphium plumosum L. exhibit promising antidiabetic potential, offering alternative approaches to diabetes management. Polyherbalism, combining multiple plant extracts, may enhance therapeutic efficacy in diabetes treatment. Comprehensive research is needed to explore the combined therapeutic effects of these plants and develop more effective antidiabetic treatments. This review highlights the importance of harnessing natural resources to combat the global burden of DM. Further research is warranted to fully explore the combined therapeutic effects of these plants and develop novel treatments.

Dietary phenolic compounds as promising therapeutic agents for diabetes and its complications: A comprehensive review

In the middle of an ever-changing landscape of diabetes care, precision medicine, and lifestyle therapies are becoming increasingly important. Dietary polyphenols are like hidden allies found in our everyday meals. These biomolecules, found commonly in fruits, vegetables, and various plant-based sources, hold revolutionary potential within their molecular structure in the way we approach diabetes and its intimidating consequences. There are currently numerous types of diabetes medications, but they are not appropriate for all patients due to limitations in dosages, side effects, drug resistance, a lack of efficacy, and ethnicity. Currently, there has been increased interest in practicing herbal remedies to manage diabetes and its related complications. This article aims to summarize the potential of dietary polyphenols as a foundation in the treatment of diabetes and its associated consequences. We found that most polyphenols inhibit enzymes linked to diabetes. This review outlines the potential benefits of selected molecules, including kaempferol, catechins, rosmarinic acid, apigenin, chlorogenic acid, and caffeic acid, in managing diabetes mellitus as these compounds have exhibited promising results in in vitro, in vivo, in silico, and some preclinical trials study. This encompassing exploration reveals the multifaceted impact of polyphenols not only in mitigating diabetes but also in addressing associated conditions like inflammation, obesity, and even cancer. Their mechanisms involve antioxidant functions, immune modulation, and proinflammatory enzyme regulation. Furthermore, these molecules exhibit anti-tumor activities, influence cellular pathways, and activate AMPK pathways, offering a less toxic, cost-effective, and sustainable approach to addressing diabetes and its complications.

Flavonoids as dual-target inhibitors against α-glucosidase and α-amylase: a systematic review of in vitro studies

Diabetes mellitus remains a major global health issue, and great attention is directed at natural therapeutics. This systematic review aimed to assess the potential of flavonoids as antidiabetic agents by investigating their inhibitory effects on α-glucosidase and α-amylase, two key enzymes involved in starch digestion. Six scientific databases (PubMed, Virtual Health Library, EMBASE, SCOPUS, Web of Science, and WHO Global Index Medicus) were searched until August 21, 2022, for in vitro studies reporting IC50 values of purified flavonoids on α-amylase and α-glucosidase, along with corresponding data for acarbose as a positive control. A total of 339 eligible articles were analyzed, resulting in the retrieval of 1643 flavonoid structures. These structures were rigorously standardized and curated, yielding 974 unique compounds, among which 177 flavonoids exhibited inhibition of both α-glucosidase and α-amylase are presented. Quality assessment utilizing a modified CONSORT checklist and structure-activity relationship (SAR) analysis were performed, revealing crucial features for the simultaneous inhibition of flavonoids against both enzymes. Moreover, the review also addressed several limitations in the current research landscape and proposed potential solutions. The curated datasets are available online at https://github.com/MedChemUMP/FDIGA .

Natural Functional Beverages as an Approach to Manage Diabetes

Diabetes mellitus is a chronic disease, commonly associated with unhealthy habits and obesity, and it is becoming a serious health issue worldwide. As a result, new approaches to treat diabetes are required, and a movement towards more natural approaches is emerging. Consuming fruit and vegetables is advised to prevent diabetes since they contain several bioactive compounds. A simple and effective strategy to include them in the diets of diabetic and obese people is through beverages. This review aims to report the anti-diabetic potentials of different vegetable and fruit beverages. These functional beverages demonstrated in vitro potential to inhibit α-glucosidase and α-amylase enzymes and to improve glucose uptake. In vivo, beverage consumption showed a reduction of blood glucose, increase of insulin tolerance, improvement of lipid profile, control of obesity, and reduction of oxidative stress. This suggests the potential of vegetable- and fruit-based functional beverages to be used as a natural innovative therapy for the management of diabetes.

Evaluation of Anti-Hyperglycemia and Complications of Red and Black Thai Jasmine Rice Cultivars in Streptozotocin-Induced Diabetic Rats

The phytochemical constituents of red (RR) and black (BR) rice extracts were determined using high-pressure liquid chromatography (HPLC). Phytochemical screening revealed the presence of catechin, rutin, isoquercetin, cyanidin 3-glucoside, cyanidin 3-O-rutinoside, peonidin and quercetin. The anti-diabetic activities of RR and BR extracts on diabetic complications were examined in a streptozotocin-induced diabetic rat model. Rats (n = 80) were divided into 10 groups (n = 8 rats per group). Healthy and diabetic RR or BR-treated groups received 10, 50, or 200 mg of RR or BR per kg of body weight daily for 45 days. The results demonstrated significantly improved glucose control in rats administered RR or BR, while triglyceride and cholesterol levels were reduced in the diabetic groups. Moreover, RR or BR treatment led to decreased levels of malondialdehyde, aspartate aminotransferase, alanine aminotransferase, blood urea nitrogen, and creatinine. Further, glutathione concentration was significantly increased in both serum and liver tissue from RR- and BR-treated diabetic rats.

Pre-clinical evidence for the therapeutic effect of Pitaya (Hylocereus lemairei) on diabetic intestinal microenvironment

Intestinal glucose absorption plays a central role in the regulation of glucose plasmatic; however, current clinical management does not target the gut for treating diabetes. This study evaluated the effects of peel and pulp aqueous extract from Hylocereus lemairei on human enterocytes under high glucose concentration. Anti-hyperglycemic and antiobesity activities in vitro were also evaluated. Extracts did not cause cytotoxicity at 1 to 500 μg/mL. Moreover, they were effective in attenuating oxidative stress (DCFH-DA assay) and inflammation (^•ON production) caused by high glucose. Intestinal enzymes (α- glucosidase and pancreatic lipase) were inhibited by pulp and peel extracts (>60% and >95%, respectively). Extracts exhibited a redox capacity superior to ascorbic and chlorogenic acids, presenting high phenolic content, mainly anthocyanins. The main compounds for both extracts were chlorogenic acid and naringin, and peel stood both qualitatively and quantitatively. Data suggest red Pitaya has potential as a new medicine for diabetes.

Anabasis articulata (Forssk.) Moq: A Good Source of Phytochemicals with Antibacterial, Antioxidant, and Antidiabetic Potential

Anabasis articulata is medicinally used to treat various diseases. In this study, A. articulata was initially subjected to extraction, and the resultant extracts were then evaluated for their antimicrobial, antioxidant, and antidiabetic potentials. After obtaining the methanolic extract, it was subjected to a silica gel column for separation, and fractions were collected at equal intervals. Out of the obtained fractions (most rich in bioactive compounds confirmed through HPLC), designated as A, B, C, and D as well hexane fraction, were subjected to GC-MS analysis, and a number of valuable bioactive compounds were identified from the chromatograms. The preliminary phytochemical tests were positive for the extracts where fraction A exhibited the highest total phenolic and flavonoid contents. The hexane fraction as antimicrobial agent was the most potent, followed by the crude extract, fraction A, and fraction D. DPPH and ABTS assays were used to estimate the free radical scavenging potential of the extracts. Fraction C was found to contain potent inhibitors of both the tested radicals, followed by fraction D. The potential antidiabetic extracts were determined using α-glucosidase and amylase as probe enzymes. The former was inhibited by crude extract, hexane, and A, B, C and D fractions to the extent of 85.32 ± 0.20, 61.14 ± 0.49, 62.15 ± 0.84, 78.51 ± 0.45, 72.57 ± 0.92 and 70.61 ± 0.91%, respectively, at the highest tested concentration of 1000 µg/mL with their IC₅₀ values 32, 180, 200, 60, 120 and 140 µg/mL correspondingly, whereas α-amylase was inhibited to the extent of 83.98 ± 0.21, 58.14 ± 0.75, 59.34 ± 0.89, 81.32 ± 0.09, 74.52 ± 0.13 and 72.51 ± 0.02% (IC₅₀ values; 34, 220, 240, 58, 180, and 200 µg/mL, respectively). The observed biological potentials might be due to high phenolic and flavonoid content as detected in the extracts. The A. articulata might thus be considered an efficient therapeutic candidate and could further be investigated for other biological potentials along with the isolation of pure responsible ingredients.

Rosinidin Flavonoid Ameliorates Hyperglycemia, Lipid Pathways and Proinflammatory Cytokines in Streptozotocin-Induced Diabetic Rats

Diabetes is one of the world’s most important public health issues, impacting both public health and socioeconomic advancement; moreover, current pharmacotherapy is still insufficient. The natural flavonoid rosinidin has a long history of use in pharmaceuticals and nutritional supplements, but its role in diabetes has been unknown. The current study was intended to confirm the anti-diabetic activity of rosinidin in our laboratory setting, along with its mechanism. Streptozotocin (60 mg/kg, ip) treatment used to induce type II diabetes in rats and the test medication rosinidin was then administered orally (at doses of 10 mg/kg and 20 mg/kg) for biochemical and histopathological analysis. Treatment with rosinidin reduced negative consequences of diabetes. Rosinidin exerted a protective effect on a number of characteristics, including anti-diabetic responses (lower blood glucose, higher serum insulin and improved pancreatic function) and molecular mechanisms (favorable effects on lipid profiles, total protein, albumin, liver glycogen, proinflammatory cytokine, antioxidant and oxidative stress markers, AST, ALT and urea). Furthermore, the improved pancreatic architecture observed in tissues substantiated the favourable actions of rosinidin in STZ-induced diabetic rats.

Does Oxidative Stress Management Help Alleviation of COVID-19 Symptoms in Patients Experiencing Diabetes?

Severe acute respiratory syndrome (SARS)-CoV-2 virus causes novel coronavirus disease 2019 (COVID-19) with other comorbidities such as diabetes. Diabetes is the most common cause of diabetic nephropathy, which is attributed to hyperglycemia. COVID-19 produces severe complications in people with diabetes mellitus. This article explains how SARS-CoV-2 causes more significant kidney damage in diabetic patients. Importantly, COVID-19 and diabetes share inflammatory pathways of disease progression. SARS-CoV-2 binding with ACE-2 causes depletion of ACE-2 (angiotensin-converting enzyme 2) from blood vessels, and subsequently, angiotensin-II interacts with angiotensin receptor-1 from vascular membranes that produce NADPH (nicotinamide adenine dinucleotide hydrogen phosphate) oxidase, oxidative stress, and constriction of blood vessels. Since diabetes and COVID-19 can create oxidative stress, we hypothesize that COVID-19 with comorbidities such as diabetes can synergistically increase oxidative stress leading to end-stage renal failure and death. Antioxidants may therefore prevent renal damage-induced death by inhibiting oxidative damage and thus can help protect people from COVID-19 related comorbidities. A few clinical trials indicated how effective the antioxidant therapy is against improving COVID-19 symptoms, based on a limited number of patients who experienced COVID-19. In this review, we tried to understand how effective antioxidants (such as vitamin D and flavonoids) can act as food supplements or therapeutics against COVID-19 with diabetes as comorbidity based on recently available clinical, preclinical, or in silico studies.

In Vivo and Ex Vivo Evaluation of 1,3-Thiazolidine-2,4-Dione Derivatives as Euglycemic Agents

Thiazolidinediones (TZDs), used to treat type 2 diabetes mellitus, act as full agonists of the peroxisome proliferator-activated receptor gamma. Unfortunately, they produce adverse effects, including weight gain, hepatic toxicity, and heart failure. Our group previously reported the design, synthesis, in silico evaluation, and acute oral toxicity test of two TZD derivatives, compounds 40 (C40) and 81 (C81), characterized as category 5 and 4, respectively, under the Globally Harmonized System. The aim of this study was to determine whether C40, C81, and a new compound, C4, act as euglycemic and antioxidant agents in male Wistar rats with streptozotocin-induced diabetes. The animals were randomly divided into six groups (n = 7): the control, those with diabetes and untreated, and those with diabetes and treated with pioglitazone, C40, C81, or C4 (daily for 21 days). At the end of the experiment, tissue samples were collected to quantify the level of glucose, insulin, triglycerides, total cholesterol, and liver enzymes, as well as enzymatic and nonenzymatic antioxidant activity. C4, without a hypoglycemic effect, displayed the best antioxidant activity. Whereas C81 could only attenuate the elevated level of blood glucose, C40 generated euglycemia by the end of the treatment. All compounds produced a significant decrease in triglycerides.

In Silico Approaches to Identify Polyphenol Compounds as α-Glucosidase and α-Amylase Inhibitors against Type-II Diabetes

Type-II diabetes mellitus (T2DM) results from a combination of genetic and lifestyle factors, and the prevalence of T2DM is increasing worldwide. Clinically, both α-glucosidase and α-amylase enzymes inhibitors can suppress peaks of postprandial glucose with surplus adverse effects, leading to efforts devoted to urgently seeking new anti-diabetes drugs from natural sources for delayed starch digestion. This review attempts to explore 10 families e.g., Bignoniaceae, Ericaceae, Dryopteridaceae, Campanulaceae, Geraniaceae, Euphorbiaceae, Rubiaceae, Acanthaceae, Rutaceae, and Moraceae as medicinal plants, and folk and herb medicines for lowering blood glucose level, or alternative anti-diabetic natural products. Many natural products have been studied in silico, in vitro, and in vivo assays to restrain hyperglycemia. In addition, natural products, and particularly polyphenols, possess diverse structures for exploring them as inhibitors of α-glucosidase and α-amylase. Interestingly, an in silico discovery approach using natural compounds via virtual screening could directly target α-glucosidase and α-amylase enzymes through Monte Carto molecular modeling. Autodock, MOE-Dock, Biovia Discovery Studio, PyMOL, and Accelrys have been used to discover new candidates as inhibitors or activators. While docking score, binding energy (Kcal/mol), the number of hydrogen bonds, or interactions with critical amino acid residues have been taken into concerning the reliability of software for validation of enzymatic analysis, in vitro cell assay and in vivo animal tests are required to obtain leads, hits, and candidates in drug discovery and development.

Multi-Mechanistic In Vitro Evaluation of Antihyperglycemic, Antioxidant and Antiglycation Activities of Three Phenolic-Rich Indian Red Rice Genotypes and In Silico Evaluation of Their Phenolic Metabolites

The study evaluated the antidiabetic potential of three traditional Indian red rice genotypes/RR (Kattuyanam/KA, Chennangi/CH & Karungkuruvai/KU) using a combination of in vitro, metabolomics (Quadrupole-Time of Flight-Liquid chromatography-Mass spectrometry/Q-TOF-LC-MS/MS), and in silico techniques. In terms of antihyperglycemic potential, KA exhibited the highest inhibitory activity against α-amylase; CH against α-glucosidase; and KU against DPPIV and PTP1B enzymes. KA exhibited the highest antioxidant activity (DPPH, FRAP, and ABTS) and greater inhibition of protein glycation compared to other RR indicating its potential to mitigate diabetic complications. The metabolomic analysis confirmed the presence of 99 phenolics in the sample extracts (KU-71, KA-70, CH-68). Molecular docking studies revealed seven metabolites to be good inhibitors of the four target enzymes and activators of insulin receptor substrate/IRS. The antihyperglycemic and oxidation-glycation reduction composite index revealed KA to have the highest overall antidiabetic potential. Hence, the RR could be utilized in functional foods with a multi-barrelled strategy for diabetes prevention/management.

Antioxidants Isolated from Elaeagnus umbellata (Thunb.) Protect against Bacterial Infections and Diabetes in Streptozotocin-Induced Diabetic Rat Model

The increase in resistance of microbes against conventional drugs is currently a hot issue, whereas diabetes is another main cause of mortalities encountered throughout the world after cancer and heart attacks. New drug sources in the form of plants are investigated to get effective drugs for the mentioned diseases with minimum side effects. Elaeagnus umbellata Thunb. is a medicinal plant used for the management of stress related disorders like diabetes and other health complications. The active constituents of the chloroform extract derived from E. umbellata berries was isolated by silica gel column chromatography which were identified as morin, phloroglucinol, and 1-hexyl benzene through various spectroscopic techniques (electron ionization mass spectrometry, 1H-NMR, and 13C-NMR spectroscopy). The possible protective effects (antioxidant, antibacterial, and antidiabetic activity) of isolated compounds were evaluated using reported methods. Morin exhibited strong in vitro antiradical potential against DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid) radicals along with prominent antibacterial activities against selected bacterial strains (Escherichia coli, Bacillus cereus, Salmonella typhi, Klebsiella pneumonia, Pseudomonas aeruginosa and Proteus mirabilis). Among the isolated compounds the more potent one (morin) was assessed for its in vivo antidiabetic potential in streptozotocin-induced diabetic rat model. The in vivo effects observed were further confirmed in ex vivo experiments where the effect of isolated compound on antioxidant enzyme like glutathione peroxidase (GPx), total content of reduced glutathione (GSH), % DPPH inhibition, and the lipid peroxidation MDA (Malondialdehyde) level in pancreatic tissues homogenates were evaluated. In vivo morin at tested doses (2, 10, 15, 30 and 50 mg/kg body weight) significantly restored the alterations in the levels of fasting blood glucose level and body weight loss along with significant decrease in levels of cholesterol, triglycerides, low density lipoprotein, HbA1c level, and significantly increased the high-density lipoprotein in diabetic rats. Morin also effectively ameliorated the hepatic enzymes, and renal functions like serum creatinine. Morin significantly increased the antioxidant enzyme like GPx activity, GSH content, and % DPPH inhibition activity, while reduced the lipid peroxidation MDA (malondialdehyde) level in pancreatic tissues homogenates, and modification of histopathological changes in diabetic rats. Morin exhibited high antioxidant, antibacterial, and antidiabetic potentials as compared to phloroglucinol and 1-hexyl benzene, that could, therefore, be considered as a promising therapeutic agent to treat diabetes mellitus and bacterial infections.

Determination of Activation Energies and the Optimum Temperatures of Hydrolysis of Starch by α-Amylase from Porcine Pancreas

The present paper reports the determination of the activation energies and the optimum temperatures of starch hydrolysis by porcine pancreas α-amylase. The parameters were estimated based on the literature data on the activity curves versus temperature for starch hydrolysis by α-amylase from porcine pancreas. It was assumed that both the hydrolysis reaction process and the deactivation process of α-amylase were first-order reactions by the enzyme concentration. A mathematical model describing the effect of temperature on porcine pancreas α-amylase activity was used. The determine deactivation energies Ea were from 19.82 ± 7.22 kJ/mol to 128.80 ± 9.27 kJ/mol, the obtained optimum temperatures Topt were in the range from 311.06 ± 1.10 K to 326.52 ± 1.75 K. In turn, the values of deactivation energies Ed has been noted in the range from 123.57 ± 14.17 kJ/mol to 209.37 ± 5.17 kJ/mol. The present study is related to the starch hydrolysis by α-amylase. In the industry, the obtained results the values Ea, Ed, Topt can be used to design and optimize starch hydrolysis by α-amylase porcine pancreas. The obtained results might also find application in research on the pharmaceutical preparations used to treat pancreatic insufficiency or prognosis of pancreatic cancer.

A Review on Antidiabetic Activity of Centaurea spp.: A New Approach for Developing Herbal Remedies

Objective

Diabetes mellitus (DM) is a long-life metabolic disorder, characterized by high blood glucose levels. The hyperglycemic condition generally leads to irreversible nerve injury and vascular damage. Among different types of diabetes, type 2 is more common and has spread all over the world. Although various therapeutic approaches have been developed to control type 2 DM, regulating blood glucose levels has still remained a controversial challenge for patients. Also, most prescription drugs cause different side effects, such as gastrointestinal disorders. Thus, developing novel and efficient antidiabetic agents possessing fewer adverse effects is in high demand.

Method

The literature was comprehensively surveyed via search engines such as Google Scholar, PubMed, and Scopus using appropriate keywords.

Results

Medicinal plants, both extracts and isolated active components, have played a significant role in controlling the blood glucose levels. Good-to-excellent results documented in the literature have made them a precious origin for developing and designing drugs and supplements against DM. Centaurea spp. have been traditionally used for controlling high blood glucose levels. Also, the antidiabetic properties of different species of Centaurea have been confirmed in recent studies through in vitro assays as well as in vivo experiments.

Conclusion

Potent results encouraged us to review their efficacy to open a new horizon for development of herbal antidiabetic agents.

Modulatory effects of catechin hydrate on benzo[a]pyrene-induced nephrotoxicity in adult male albino rats

Benzo [a] pyrene (B[a]P) is a potent mutagen and carcinogen, considered one of the commonest concomitants in the environment. The study aimed to evaluate the effect of catechin hydrate on benzo pyrene-induced kidney toxicity. Thirty-six adult male albino rats were divided into six groups: group I untreated control, group II received 10 mL/kg of corn oil (solvent of benzo [a] pyrene) twice a week, group III received 1 mL/kg 0.5% dimethyl sulfoxide (DMSO) (solvent of catechin) once per day, group IV received 50 mg/kg body weight of benzo[a]pyrene twice a week, group V received 20 mg/kg body weight of catechin in 1 mL/kg 0.5% DMSO once daily, and group VI received both catechin+benzo [a] pyrene with the same doses. All treatment was given by oral gavage for four weeks. At the end of the experiment, blood samples were collected for biochemical investigations, tissues were obtained for genotoxicity, RT-PCR, and histopathological studies. B[a]P exposure induced an increase in serum urea and creatinine levels along with severe renal histopathological changes. Our results showed a subsequent decrease in the antioxidant enzyme activities (catalase and superoxide dismutase), and conversely, (malondialdehyde) levels markedly elevated. Also, B[a]P induced DNA damage as well as activated an apoptotic pathway confirmed by upregulation of Bax, caspase-3, and downregulation of Bcl-2 expression. However, treatment with catechin-corrected kidney functions and antioxidant enzymes as well as regulated apoptosis. Histological results also supported the protective effects of catechin. These findings suggested that catechin hydrate is an effective natural product that attenuates benzo pyrene-induced kidney toxicity.

In Vitro α-Amylase and α-Glucosidase Inhibitory and Antioxidant Activities of the Crude Extract and Solvent Fractions of Hagenia abyssinica Leaves

BACKGROUND

The leaves of Hagenia abyssinica have been used in the management of diabetes mellitus in Ethiopian folk medicine. Thus, this study is aimed at investigating the in vitro α-amylase and α-glucosidase inhibitory and antioxidant activities of the crude extract and solvent fractions of H. abyssinica leaves.

METHODS

The in vitro α-amylase and α-glucosidase inhibitory and antioxidant activities of the plant extract were assessed using 3,5-dinitrosalicylic acid (DNSA), p-nitro-phenyl-a-D glucopyranoside (p-NPG), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays, respectively. Each value of percent inhibition of α-amylase, α-glucosidase, and DPPH scavenging effect was presented as means ± SEM (n = 3).

RESULTS

The α-amylase inhibitory activity of the crude extract and solvent fractions was found to be concentration-dependent. The strongest activity was exhibited by the crude extract at the highest concentration with a percentage inhibition of 74.52% (IC50, 14.52 μg/ml) followed by water fraction 68.24% (IC50, 16.31 μg/ml), ethyl acetate fraction 61.57% (IC50, 18.73 μg/ml), and chloroform fraction 56.87% (IC50, 21.57 μg/ml) of H. abyssinica leaves. In the α-glucosidase inhibition assay, the maximum activity was exhibited by the aqueous fraction 62.54% (IC50, 11.67 μg/ml) followed by ethyl acetate fraction 54.97% (IC50, 15.89 μg/ml), crude extract 46.79% (IC50, >16.5 μg/ml), and chloroform fraction 36.44% (IC50, >16.5 μg/ml). In the antioxidant assay, the crude extract exhibited the highest antioxidant activity 86.36% (IC50, 10.25 μg/ml) followed by water fraction 78.59% (IC50, 13.86 μg/ml), ethyl acetate fraction 71.58% (IC50, 16.34 μg/ml), and chloroform fraction 63.65% (IC50, 18.83 μg/ml).

CONCLUSION

This study has revealed that H. abyssinica leaves possess noticeable in vitro α-amylase and α-glucosidase inhibitory and antioxidant activities.

Phytochemicals against anti-diabetic complications: targeting the advanced glycation end product signaling pathway

The role of advanced glycation end products (AGEs) is not limited to diabetes and diabetes-related complications. There are multiple modulators, including the receptor for advanced glycation end products, high mobility group box 1, glyoxalase 1, nuclear factor-kappa B, tumor necrosis factor-α, chronic unpredictable stress, reactive oxygen species, and inflammatory cytokines, which interact with AGE signaling and control diabetes, modulating these interacting modulators. The progression of diabetes, as well as related complications, can be controlled and treated. Natural products rich in bioactive constituents can interact with AGEs and their related mediators through various signaling cascades, thereby controlling and preventing the progression of diabetes. This review provides a deeper assessment of the signaling pathway, interactions between phytochemicals and AGEs, and its mediators, to develop a multifold therapeutic approach to prevent and treat diabetes and its related complications.