The Role of Natural Products on Diabetes Mellitus Treatment: A Systematic Review of Randomized Controlled Trials

"GC-MS profiling, sub-acute toxicity study and total phenolic and flavonoid content analysis of methanolic leaf extract of Schima wallichii (D.C.) Korth-a traditional antidiabetic medicinal plant"

ETHNOPHARMACOLOGICAL RELEVANCE

Schima wallichii (D.C.) Korth is traditionally used in Manipur, India for treatment of diabetes and hypertension. However, there is no data reported regarding safety profile of this medicinal plant upon repeated per oral administration over a period of time.

AIM OF THE STUDY

In the current study phytochemical profile, toxicological profile and total phenolic and flavonoid compound content of Schima wallichii leaves extract were evaluated.

MATERIALS AND METHODS

Gas chromatography coupled to mass spectrometry was performed for chemical profiling by using Gas Chromatography-Mass Spectrometry/Mass Spectrometry (GC-MS/MS), Shimadzu, TQ8040 system. A 28 days sub-acute toxicity study was carried out using albino Wistar rats by administering 3 different doses (200, 400 and 800 mg/kg body weight per oral) of methanol leaves extract. Changes in body weights were recorded weekly. Serum biochemical parameters were estimated as well as blood-cell count was done to check the effect of extract on haematopoietic system. Histopathology of vital organs viz. kidney, heart, brain, liver was performed to find any pathological indications. Since, liver is main the site for xenobiotic metabolism, estimation of the level of glutathione, catalase and lipid peroxidation were done. Further, total phenolic and flavonoid compound content estimation was performed for the leaves extract.

RESULTS

GC-MS revealed 14 major compounds with area percentage >1% of which quinic acid, n-Hexadecanoic acid, 9,12,15-Octadecatrienoic acid, (Z,Z,Z)-, Octatriacontyl trifluoroacetate, are three major compounds. No mortality was observed after the treatment with extract. Blood-cell count and biochemical parameters didn't show significant deviation as compared to control group. Histopathology study of vital organs viz. (liver, kidney, heart and brain) showed normal cellular construction comparing to control group. There was no sign of membrane lipid peroxidation, depletion of catalase level and glutathione level in liver. The result demonstrates that NOAEL (no-observed-adverse-effect levels) in the sub-acute toxicity was above 800 mg/kg. The leaves extract showed significant total phenol and flavonoid content.

CONCLUSION

The present study revealed that Schima wallichii possessed important bioactive compounds with therapeutic values. The plant was safe for consumption after repeated high doses administration in rats and possesses significant amount of total phenol and flavonoid content.

Antidiabetic potency and molecular insights of natural products bearing indole moiety: A systematic bioinformatics investigation targeting AKT1

Diabetic mellitus (DM) is a chronic disorder, and type 2 DM (T2DM) is the most prevalent among all categories (nearly 90%) across the globe every year. With the availability of potential drugs, the prevalence rate has remained uncontrollable, while natural resources showed a promising potency, and exploring such potential candidates at the preclinical stage is essential. An extensive literature search selected 89 marine and plant-derived indole derivatives with anti-inflammatory, antioxidant, lipid-lowering, etc., activities. However, as we know, drugs have not been able to convert from 'lead' to 'mainstream' due to inadequate drug-ability profiles, as our systematic investigation proved and selected herdmanine_A (HERD_A) and penerpene_D (PENE_D) as the most potential antidiabetic candidates from the library of indole derivatives. Based on our previous network pharmacology study, we selected three new target enzymes: Acetyl-CoA carboxylase 2 (ACACB; PDB ID: 3JRX), cyclin-dependent kinase 4 (CDK4; PDB ID: 3G33), and alpha serine/threonine-protein kinase 1 (AKT1; PDB ID: 3O96) to assess the antidiabetic potency of selected indole derivatives through binding energy or docking score. To conduct molecular docking studies with these enzymes, we used the PyRx-AutoDock platform. Furthermore, molecular dynamic simulation at 100 ns, physicochemical analysis, pharmacokinetics, toxicity assessment, and drug-likeness evaluation suggested that HERD_A and penerpene PENE_D were the most potent inhibitors against AKT1 compared to koenimbine (most potential based on the recorded IC50 value) and murrayakonine_A (most potential based on the docking score). In summary, HERD_A and/or PENE_D have the potential to be used as alternative therapeutic agent for the treatment of diabetes after some pharmacological investigation.

Beneficial Effects of Echinacoside on Cognitive Impairment and Diabetes in Type 2 Diabetic db/db Mice

INTRODUCTION

Cognitive dysfunction is an important comorbidity of diabetes. Insulin resistance may play a critical role in diabetes-related cognitive impairment. Echinacoside (ECH), a natural phenylethanoid glycoside, is the active component of anti-diabetes prescriptions in traditional Chinese medicine. Its effect on modulating insulin resistance has been confirmed but modulating neurodegenerative disease remains unclear.

METHODS

Db/db mice, a spontaneous type 2 diabetes mode, were intragastrically administered ECH by 300 mg/kg or an equivalent volume of saline. Weight, blood glucose, and insulin resistance index were measured. Morris water maze test was performed to observe the compound effects on cognition. Hippocampal lesions were observed by histochemical analysis.

RESULTS

In db/db mice, ECH alleviated diabetes symptoms, memory loss, and hippocampal neuronal damage. Next, the expression of CD44 and phosphorylated tau was upregulated in diabetic mice. In addition, the insulin receptor substrate-1/phosphatidylinositol 3-kinase /protein kinase B signaling pathway was dysregulated in diabetic mice. All these dysregulations could be reversed by ECH.

DISCUSSION

This study provides theoretical support and experimental evidence for the future application of ECH in diabetic cognition dysfunction treatment, promoting the development of traditional medicines.

Application of effect-directed analysis using TLC-bioautography for rapid isolation and identification of antidiabetic compounds from the leaves of Annona cherimola Mill

INTRODUCTION

Type 2 diabetes mellitus is a globally prevalent chronic disease characterised by hyperglycaemia and oxidative stress. The search for new natural bioactive compounds that contribute to controlling this condition and the application of analytical methodologies that facilitate rapid detection and identification are important challenges for science. Annona cherimola Mill. is an important source of aporphine alkaloids with many bioactivities.

OBJECTIVE

The aim of this study is to isolate and identify antidiabetic compounds from alkaloid extracts with α-glucosidase and α-amylase inhibitory activity from A. cherimola Mill. leaves using an effect-directed analysis by thin-layer chromatography (TLC)-bioautography.

METHODOLOGY

Guided fractionation for α-glucosidase and α-amylase inhibitors in leaf extracts was done using TLC-bioassays. The micro-preparative TLC was used to isolate the active compounds, and the identification was performed by mass spectrometry associated with web-based molecular networks. Additionally, in vitro estimation of the inhibitory activity and antioxidant capacity was performed in the isolated compounds.

RESULTS

Five alkaloids (liriodenine, dicentrinone, N-methylnuciferine, anonaine, and moupinamide) and two non-alkaloid compounds (3-methoxybenzenepropanoic acid and methylferulate) with inhibitory activity were isolated and identified using a combination of simple methodologies. Anonaine, moupinamide, and methylferulate showed promising results with an outstanding inhibitory activity against both enzymes and antioxidant capacity that could contribute to controlling redox imbalance.

CONCLUSIONS

These high-throughput methodologies enabled a rapid isolation and identification of seven compounds with potential antidiabetic activity. To our knowledge, the estimated inhibitory activity of dicentrinone, N-methylnuciferine, and anonaine against α-glucosidase and α-amylase is reported here for the first time.

Myricetin encapsulated chitosan nanoformulation for management of type 2 diabetes: Preparation, optimization, characterization and in vivo activity

Type 2 diabetes mellitus (T2DM) is a serious and alarming disease attracting widespread attention. It is not a single metabolic disease; over time, it leads to serious disorders, namely, diabetic nephropathy, neuropathy, retinopathy and several cardiovascular, hepatocellular complications. The increase in T2DM cases in recent times has attracted significant attention. Currently, the medications available have side effects, and injectables are painful, causing trauma to the patients. Therefore, it is imperative to come up with oral delivery. In this background we report here a nanoformulation carrying natural small molecule Myricetin (MYR) encapsulated within Chitosan nanoparticles (CHT-NPs). MYR-CHT-NPs were prepared by ionic gelation method and evaluated using different characterization techniques. The in vitro release of MYR from CHT NPs in different physiological media showed pH dependence. in vivo pharmacodynamic study followed by oral administration in Albino Wistar rats showed better glycaemic control than existing drug. Further, the optimized nanoparticles also exhibited controlled increase in weight as compared to Metformin. The biochemistry profile of rats treated with nanoformulation reduced the levels of several pathological biomarkers, indicating additional benefits of MYR. Histopathological images exhibited no toxicity or changes in the major organs section in contrast to normal control, suggesting safe oral administration of the encapsulated MYR. Thus, we conclude that MYR-CHT-NPs represent an attractive delivery vehicle in improving the blood glucose level with controlled weight and have the potential to be safely administered orally for the management of T2DM.

Algae-Derived Natural Products in Diabetes and Its Complications-Current Advances and Future Prospects

Diabetes poses a significant global health challenge, necessitating innovative therapeutic strategies. Natural products and their derivatives have emerged as promising candidates for diabetes management due to their diverse compositions and pharmacological effects. Algae, in particular, have garnered attention for their potential as a source of bioactive compounds with anti-diabetic properties. This review offers a comprehensive overview of algae-derived natural products for diabetes management, highlighting recent developments and future prospects. It underscores the pivotal role of natural products in diabetes care and delves into the diversity of algae, their bioactive constituents, and underlying mechanisms of efficacy. Noteworthy algal derivatives with substantial potential are briefly elucidated, along with their specific contributions to addressing distinct aspects of diabetes. The challenges and limitations inherent in utilizing algae for therapeutic interventions are examined, accompanied by strategic recommendations for optimizing their effectiveness. By addressing these considerations, this review aims to chart a course for future research in refining algae-based approaches. Leveraging the multifaceted pharmacological activities and chemical components of algae holds significant promise in the pursuit of novel antidiabetic treatments. Through continued research and the fine-tuning of algae-based interventions, the global diabetes burden could be mitigated, ultimately leading to enhanced patient outcomes.

Chemical Constituents from the Roots of Angelica reflexa That Improve Glucose-Stimulated Insulin Secretion by Regulating Pancreatic β-Cell Metabolism

The aim of this study was to discover bioactive constituents of Angelica reflexa that improve glucose-stimulated insulin secretion (GSIS) in pancreatic β-cells. Herein, three new compounds, namely, koseonolin A (1), koseonolin B (2), and isohydroxylomatin (3), along with 28 compounds (4-31) were isolated from the roots of A. reflexa by chromatographic methods. The chemical structures of new compounds (1-3) were elucidated through spectroscopic/spectrometric methods such as NMR and HRESIMS. In particular, the absolute configuration of the new compounds (1 and 3) was performed by electronic circular dichroism (ECD) studies. The effects of the root extract of A. reflexa (KH2E) and isolated compounds (1-31) on GSIS were detected by GSIS assay, ADP/ATP ratio assay, and Western blot assay. We observed that KH2E enhanced GSIS. Among the compounds 1-31, isohydroxylomatin (3), (-)-marmesin (17), and marmesinin (19) increased GSIS. In particular, marmesinin (19) was the most effective; this effect was superior to treatment with gliclazide. GSI values were: 13.21 ± 0.12 and 7.02 ± 0.32 for marmesinin (19) and gliclazide at a same concentration of 10 μM, respectively. Gliclazide is often performed in patients with type 2 diabetes (T2D). KH2E and marmesinin (19) enhanced the protein expressions associated with pancreatic β-cell metabolism such as peroxisome proliferator-activated receptor γ, pancreatic and duodenal homeobox 1, and insulin receptor substrate-2. The effect of marmesinin (19) on GSIS was improved by an L-type Ca²⁺ channel agonist and K+ channel blocker and was inhibited by an L-type Ca²⁺ channel blocker and K⁺ channel activator. Marmesinin (19) may improve hyperglycemia by enhancing GSIS in pancreatic β-cells. Thus, marmesinin (19) may have potential use in developing novel anti-T2D therapy. These findings promote the potential application of marmesinin (19) toward the management of hyperglycemia in T2D.

Formulation and Optimization of Repaglinide Nanoparticles Using Microfluidics for Enhanced Bioavailability and Management of Diabetes

The technologies for fabrication of nanocrystals have an immense potential to improve solubility of a variety of the poor water-soluble drugs with subsequent enhanced bioavailability. Repaglinide (Rp) is an antihyperglycemic drug having low bioavailability due to its extensive first-pass metabolism. Microfluidics is a cutting-edge technique that provides a new approach for producing nanoparticles (NPs) with controlled properties for a variety of applications. The current study’s goal was to engineer repaglinide smart nanoparticles (Rp-Nc) utilizing microfluidic technology (Dolomite Y shape), and then to perform in-vitro, in-vivo, and toxicity evaluations of them. This method effectively generated nanocrystals with average particle sizes of 71.31 ± 11 nm and a polydispersity index (PDI) of 0.072 ± 12. The fabricated Rp’s crystallinity was verified by Differential scanning calorimetry (DSC) and Powder X-ray diffraction (PXRD). In comparison to the raw and commercially available tablets, the fabricated Rp’s nanoparticles resulted in a higher saturation solubility and dissolving rate (p < 0.05). Rp nanocrystals had a considerably lower (p < 0.05) IC50 value than that of the raw drug and commercial tablets. Moreover, Rp nanocrystals at the 0.5 and 1 mg/kg demonstrated a significant decrease in blood glucose level (mg/dL, p < 0.001, n = 8) compared to its counterparts. Rp nanocrystals at the 0.5 mg/kg demonstrated a significant decrease (p < 0.001, n = 8) in blood glucose compared to its counterparts at a dose of 1 mg/kg. The selected animal model’s histological analyses and the effect of Rp nanocrystals on several internal organs were determined to be equivalent to those of the control animal group. The findings of the present study indicated that nanocrystals of Rp with improved anti-diabetic properties and safety profiles can be successfully produced using controlled microfluidic technology, an innovative drug delivery system (DDS) approach.

Chemical and Biological Review of Endophytic Fungi Associated with Morus sp. (Moraceae) and In Silico Study of Their Antidiabetic Potential

The chronic nature of diabetes mellitus motivates the quest for novel agents to improve its management. The scarcity and prior uncontrolled utilization of medicinal plants have encouraged researchers to seek new sources of promising compounds. Recently, endophytes have presented as eco-friendly leading sources for bioactive metabolites. This article reviewed the endophytic fungi associated with Morus species and their isolated compounds, in addition to the biological activities tested on their extracts and chemical constituents. The relevant literature was collected from the years 2008-2022 from PubMed and Web of Science databases. Notably, no antidiabetic activity was reported for any of the Morus-associated endophytic fungal extracts or their twenty-one previously isolated compounds. This encouraged us to perform an in silico study on the previously isolated compounds to explore their possible antidiabetic potential. Furthermore, pharmacokinetic and dynamic stability studies were performed on these compounds. Upon molecular docking, Colletotrichalactone A (14) showed a promising antidiabetic activity due to the inhibition of the α-amylase local target and the human sodium-glucose cotransporter 2 (hSGT2) systemic target with safe pharmacokinetic features. These results provide an in silico interpretation of the possible anti-diabetic potential of Morus endophytic metabolites, yet further study is required.