OBJECTIVE

Manihot esculenta (Crantz) leaves have been used for the management of diabetes based on cited ethnopharmacological studies. However, scientific evidence to support its efficacy is lacking. The aim of the study was to assess the cytotoxicity of the aqueous leaf extract and fractions of Manihot esculenta and its potential hypoglycemic effect on male Swiss albino mice.

The cytotoxicity assay was necessary to screen which extract and fractions will be used for the in vivo hypoglycemic study.

Phytochemical screening identified the composition of the aqueous crude extract and its fractions. The phytochemical results showed the presence of alkaloids, anthraquinone glycosides, carbohydrates, phenolic glycosides, saponins, and flavonoids.

Cytotoxicity was screened using CytoTox 96® (Promega), a NonRadioactive Cytotoxicity Assay on liver cancer (HepG2) and normal kidney (HK-2) cell lines. Five samples were tagged as highly cytotoxic and were flagged for further assays. These samples were DCM fraction (100 ppm), n-Hexane fraction (1 and 10 ppm), Ethyl acetate fraction (1 ppm), and Aqueous fraction (100 ppm).

The hypoglycemic activity was examined in alloxan-induced diabetic mice using in vivo hypoglycemic study. The aqueous crude extract at dose levels of 200 mg/kg and 300 mg/kg body weight showed significant reduction in blood glucose levels compared to the diabetic control but not exceeding the results in the metformin treatment group. A p-value of 0.05 set a priori was used to consider whether the intervention had a statistically significant difference compared to the diabetic control.

The effectiveness of aqueous crude extract in reduction of blood glucose in mice may be attributed to the synergistic effects of phytochemicals present, especially the alkaloids which were retained in the extract but were undetectable in the fractionated samples. The results of this study also support the findings of existing ethnopharmacological studies on M. esculenta leaf extract as a hypoglycemic agent.

Humans ; Diabetes Mellitus, Type 1 ; Hypoglycemia/chemically induced* ; Hypoglycemic Agents/adverse effects* ; China ; Blood Glucose ; Insulin

Background: One of the therapeutic strategies for type 2 diabetes mellitus involves suppressing postprandial hyperglycemia by inhibiting key enzymes in carbohydrate digestion, α-glucosidase and α-amylase. While such inhibitors are commercially available, some researchers have turned to plants for potentially cheaper and safer alternatives. Objectives: The study aimed to investigate the in vitro α-glucosidase and α-amylase inhibitory activities of the leaf methanolic extracts of two native Philippine plants Ficus nota Blanco Merr. and Ficus septica Burm F, as well as their effects on postprandial blood glucose levels in a mouse model. Methodology: The in vitro activities of the leaf methanolic extracts were evaluated against porcine pancreatic α-amylase and yeast αglucosidase. The most active extract was partially purified into fractions by sequential solvent partitioning and subjected to in vitro testing. Postprandial antihyperglycemic activity was then assessed in normoglycemic ICR mice. Phytochemical analysis was also performed Results: The most active extract and fraction in vitro were FS-crude and FS-HexF, respectively, having significantly more potent αglucosidase inhibitory activity than the commercial drug acarbose. FS-crude and FS-HexF exhibited strong inhibition of αglucosidase and weak inhibition of α-amylase, which is considered favorable for novel inhibitors as it is hypothesized to reduce gastrointestinal adverse effects. However, FS-crude and FS-HexF did not significantly attenuate postprandial blood glucose levels in the oral starch tolerance test. Phytochemical analysis of FS-HexF putatively identified 6-gingerol as one of the possible bioactive components. Conclusion F. septica could be a potential source of glycoside inhibitors as it showed promising in vitro inhibition of α-amylase and α-glucosidase. While it did not exhibit significant postprandial antihyperglycemic activity in this study, more robust testing is recommended to make a definitive conclusion.
Amylases ; Glucosidases ; Hypoglycemic Agents

Objective: Manihot esculenta (Crantz) leaves have been used for the management of diabetes based on cited ethnopharmacological studies. However, scientific evidence to support its efficacy is lacking. The aim of the study was to assess the cytotoxicity of the aqueous leaf extract and fractions of Manihot esculenta and its potential hypoglycemic effect on male Swiss albino mice. Methods: The cytotoxicity assay was necessary to screen which extract and fractions will be used for the in vivo hypoglycemic study. : Phytochemical screening identified the composition of the aqueous crude extract and its fractions. The phytochemical results showed the presence of alkaloids, anthraquinone glycosides, carbohydrates, phenolic glycosides, saponins, and flavonoids. : Cytotoxicity was screened using CytoTox 96® (Promega), a NonRadioactive Cytotoxicity Assay on liver cancer (HepG2) and normal kidney (HK-2) cell lines. Five samples were tagged as highly cytotoxic and were flagged for further assays. These samples were DCM fraction (100 ppm), n-Hexane fraction (1 and 10 ppm), Ethyl acetate fraction (1 ppm), and Aqueous fraction (100 ppm). Results: The hypoglycemic activity was examined in alloxan-induced diabetic mice using in vivo hypoglycemic study. The aqueous crude extract at dose levels of 200 mg/kg and 300 mg/kg body weight showed significant reduction in blood glucose levels compared to the diabetic control but not exceeding the results in the metformin treatment group. A p-value of 0.05 set a priori was used to consider whether the intervention had a statistically significant difference compared to the diabetic control. Conclusion The effectiveness of aqueous crude extract in reduction of blood glucose in mice may be attributed to the synergistic effects of phytochemicals present, especially the alkaloids which were retained in the extract but were undetectable in the fractionated samples. The results of this study also support the findings of existing ethnopharmacological studies on M. esculenta leaf extract as a hypoglycemic agent.
alkaloids ; hypoglycemic agents ; ethnopharmacology

To develop a novel glucose-lowering biomedicine with potential benefits in the treatment of type 2 diabetes, we used the 10rolGLP-1 gene previously constructed in our laboratory and the CRISPR/Cas9 genome editing technique to create an engineered Saccharomyces cerevisiae strain. The gRNA expression vector pYES2-gRNA, the donor vector pNK1-L-PGK-10rolGLP-1-R and the Cas9 expression vector pGADT7-Cas9 were constructed and co-transformed into S. cerevisiae INVSc1 strain, with the PGK-10rolGLP-1 expressing unit specifically knocked in through homologous recombination. Finally, an S. cerevisiae strain highly expressing the 10rolGLP-1 with glucose-lowering activity was obtained. SDS-PAGE and Western blotting results confirmed that two recombinant strains of S. cerevisiae stably expressed the 10rolGLP-1 and exhibited the desired glucose-lowering property when orally administered to mice. Hypoglycemic experiment results showed that the recombinant hypoglycemic S. cerevisiae strain offered a highly hypoglycemic effect on the diabetic mouse model, and the blood glucose decline was adagio, which can avoid the dangerous consequences caused by rapid decline in blood glucose. Moreover, the body weight and other symptoms such as polyuria also improved significantly, indicating that the orally hypoglycemic S. cerevisiae strain that we constructed may develop into an effective, safe, economic, practical and ideal functional food for type 2 diabetes mellitus treatment.
Mice ; Animals ; Saccharomyces cerevisiae/metabolism* ; CRISPR-Cas Systems ; Glucose/metabolism* ; Blood Glucose/metabolism* ; Diabetes Mellitus, Type 2/therapy* ; Hypoglycemic Agents/metabolism*

In this study, we presented the isolation and characterization of eight novel seco-guaianolide sesquiterpenoids (1-8) and two known guaianolide derivatives (9 and 10), from the aerial part of Achillea alpina L.. Compounds 1-3 were identified as guaianolides bearing an oxygen insertion at the 2, 3 position, while compounds 4-8 belonged to a group of special 3-nor guaianolide sesquiterpenoids. The structural elucidation of 1-8, including their absolute configurations, were accomplished by a combination of spectroscopic data analysis and quantum electronic circular dichroism (ECD) calculations. To evaluate the potential antidiabetic activity of compounds 1-10, we investigated their effects on glucose consumption in palmitic acid (PA)-mediated HepG2-insulin resistance (IR) cells. Among the tested compounds, compound 7 demonstrated the most pronounced ability to reverse IR. Moreover, a mechanistic investigation revealed that compound 7 exerted its antidiabetic effect by reducing the production of the pro-inflammatory cytokine IL-1β, which was achieved through the suppression of the NLRP3 pathway.
Humans ; Hypoglycemic Agents/pharmacology* ; Circular Dichroism ; Cytokines ; Glucose ; Hep G2 Cells ; Insulin Resistance

OBJECTIVE: To explore the association between the use of metformin and the risk of ischemic stroke in patients with type 2 diabetes. METHODS: A prospective cohort study was designed from the Fangshan family cohort in Beijing. According to metformin use at baseline, 2 625 patients with type 2 diabetes in Fangshan, Beijing were divided into metformin group or non-metformin group and the incidence of ischemic stroke between the different groups during follow-up was estimated and compared by Cox proportional hazard regression model. The participants with metformin were first compared with all the parti-cipants who did not use metformin, and then were further compared with those who did not use hypoglycemic agents and those who used other hypoglycemic agents. RESULTS: The patients with type 2 diabetes were with an average age of (59.5±8.7) years, and 41.9% of them were male. The median follow-up time was 4.5 years. A total of 84 patients developed ischemic stroke during follow-up, with a crude incidence of 6.4 (95%CI: 5.0-7.7) per 1 000 person-years. Among all the participants, 1 149 (43.8%) took metformin, 1 476 (56.2%) were metformin non-users, including 593 (22.6%) used other hypoglycemic agents, and 883 (33.6%) did not use any hypoglycemic agents. Compared with metformin non-users, the Hazard ratio (HR) for ischemic stroke in metformin users was 0.58 (95%CI: 0.36-0.93; P = 0.024). Compared with other hypoglycemic agents, HR was 0.48 (95%CI: 0.28-0.84; P < 0.01); Compared with the group without hypoglycemic agents, HR was 0.65 (95%CI: 0.37-1.13; P=0.13). The association between metformin and ischemic stroke was statistically significant in the patients ≥ 60 years old compared with all the metformin non-users and those who used other hypoglycemic agents (HR: 0.48, 95%CI: 0.25-0.92; P < 0.05). Metformin use was associated with a lower incidence of ischemic stroke in the patients with good glycemic control (0.32, 95%CI: 0.13-0.77; P < 0.05). In the patients with poor glycemic control, and the association was not statistically significant (HR: 0.97, 95%CI: 0.53-1.79; P>0.05). There was an interaction between glycemic control and metformin use on incidence of ischemic stroke (P_interaction < 0.05). The results of the sensitivity analysis were consistent with the results in the main analysis. CONCLUSION Among patients with type 2 diabetic in rural areas of northern China, metformin use was associated with lower incidence of ischemic stroke, especially in patients older than 60 years. There was an interaction between glycemic control and metformin use in the incidence of ischemic stroke.
Humans ; Male ; Middle Aged ; Aged ; Female ; Metformin/adverse effects* ; Diabetes Mellitus, Type 2/drug therapy* ; Cohort Studies ; Ischemic Stroke/complications* ; Prospective Studies ; Hypoglycemic Agents/adverse effects* ; Stroke/prevention & control* ; Retrospective Studies

Metformin has been used for the treatment of type II diabetes mellitus for decades due to its safety, low cost, and outstanding hypoglycemic effect clinically. The mechanisms underlying these benefits are complex and still not fully understood. Inhibition of mitochondrial respiratory-chain complex I is the most described downstream mechanism of metformin, leading to reduced ATP production and activation of AMP-activated protein kinase (AMPK). Meanwhile, many novel targets of metformin have been gradually discovered. In recent years, multiple pre-clinical and clinical studies are committed to extend the indications of metformin in addition to diabetes. Herein, we summarized the benefits of metformin in four types of diseases, including metabolic associated diseases, cancer, aging and age-related diseases, neurological disorders. We comprehensively discussed the pharmacokinetic properties and the mechanisms of action, treatment strategies, the clinical application, the potential risk of metformin in various diseases. This review provides a brief summary of the benefits and concerns of metformin, aiming to interest scientists to consider and explore the common and specific mechanisms and guiding for the further research. Although there have been countless studies of metformin, longitudinal research in each field is still much warranted.
Humans ; Metformin/pharmacokinetics* ; Diabetes Mellitus, Type 2/metabolism* ; Hypoglycemic Agents/pharmacology* ; AMP-Activated Protein Kinases/metabolism* ; Aging

Diabetes mellitus is a chronic disease, typified by hyperglycemia resulting from failures in complex multifactorial metabolic functions, that requires life-long medication. Prolonged uncontrolled hyperglycemia leads to micro- and macro-vascular complications. Although antidiabetic drugs are prescribed as the first-line treatment, many of them lose efficacy over time or have severe side effects. There is a lack of in-depth study on the patents filed concerning the use of natural compounds to manage diabetes. Thus, this patent analysis provides a comprehensive report on the antidiabetic therapeutic activity of 6 phytocompounds when taken alone or in combinations. Four patent databases were searched, and 17,649 patents filed between 2001 and 2021 were retrieved. Of these, 139 patents for antidiabetic therapeutic aids that included berberine, curcumin, gingerol, gymnemic acid, gymnemagenin and mangiferin were analyzed. The results showed that these compounds alone or in combinations, targeting acetyl-coenzyme A carboxylase 2, serine/threonine protein kinase, α-amylase, α-glucosidase, lipooxygenase, phosphorylase, peroxisome proliferator-activated receptor-γ (PPARγ), protein tyrosine phosphatase 1B, PPARγ co-activator-1α, phosphoinositide 3-kinase and protein phosphatase 1 regulatory subunit 3C, could regulate glucose metabolism which are validated by pharmacological rationale. Synergism, or combination therapy, including different phytocompounds and plant extracts, has been studied extensively and found effective, whereas the efficacy of commercial drugs in combination with phytocompounds has not been studied in detail. Curcumin, gymnemic acid and mangiferin were found to be effective against diabetes-related complications. Please cite this article as: DasNandy A, Virge R, Hegde HV, Chattopadhyay D. A review of patent literature on the regulation of glucose metabolism by six phytocompounds in the management of diabetes mellitus and its complications. J Integr Med. 2023; 21(3): 226-235.
Humans ; PPAR gamma/metabolism* ; Curcumin/therapeutic use* ; Phosphatidylinositol 3-Kinases ; Diabetes Mellitus/drug therapy* ; Hypoglycemic Agents/pharmacology* ; Hyperglycemia/drug therapy* ; Glucose

Humans ; Child, Preschool ; Insulin/therapeutic use* ; Diabetes Mellitus, Type 1/drug therapy* ; Retrospective Studies ; Hypoglycemic Agents/therapeutic use* ; Diabetes Mellitus, Type 2 ; Blood Glucose