Catechin-loaded Eudragit microparticles for the management of diabetes: formulation, characterization andin vivoevaluation of antidiabetic efficacy

A Comprehensive Review of Natural Flavonoids with Anti-SARS-CoV-2 Activity

The COVID-19 pandemic caused by SARS-CoV-2 has majorly impacted public health and economies worldwide. Although several effective vaccines and drugs are now used to prevent and treat COVID-19, natural products, especially flavonoids, showed great therapeutic potential early in the pandemic and thus attracted particular attention. Quercetin, baicalein, baicalin, EGCG (epigallocatechin gallate), and luteolin are among the most studied flavonoids in this field. Flavonoids can directly or indirectly exert antiviral activities, such as the inhibition of virus invasion and the replication and inhibition of viral proteases. In addition, flavonoids can modulate the levels of interferon and proinflammatory factors. We have reviewed the previously reported relevant literature researching the pharmacological anti-SARS-CoV-2 activity of flavonoids where structures, classifications, synthetic pathways, and pharmacological effects are summarized. There is no doubt that flavonoids have great potential in the treatment of COVID-19. However, most of the current research is still in the theoretical stage. More studies are recommended to evaluate the efficacy and safety of flavonoids against SARS-CoV-2.

A nutraceutical combination of cinnamon, purple onion, and tea linked with key enzymes on treatment of type 2 diabetes

Diabetes mellitus (DM) is concomitant with significant morbidity and mortality and its prevalence is accumulative worldwide. The conventional antidiabetic agents are known to mitigate the symptoms of diabetes; however, they may also cause adverse effects. This study was to explore the efficacy of polyherbal dietary supplement cinnamon, purple onion, and tea on the mediation of postprandial hyperglycemia in the search of combinations with a maximal response. A starch solution (3 g/kg Bwt) of oral starch tolerance test (OSTT) and glucose solution (4 g/kg Bwt) of oral glucose tolerance test (OGTT) with and without cinnamon, purple onion, tea extract (15 mg/kg Bwt), and mixture (each 5 mg/kg Bwt, 1:1:1), metformin (14 mg/kg Bwt), or acarbose (50 mg/kg Bwt) was administered to high fat plus high fructose-induced diabetic mice after an overnight fast. Postprandial plasma glucose levels were measured and changed areas under the response curve were calculated to find out the maximal efficacy of optimal polyherbal combinations. Compared with acarbose, the mixture of extracts (purple onion, cinnamon, and tea) indicated the decreasing blood glucose in OSTT. In OGTT, the mixture of extracts showed greater efficacy for hypoglycemia when compared with metformin. The molecular docking of α-amylase, α-glucosidase, and AMPK was further confirmed the putatively acting molecules from the extracts of purple onion, cinnamon, and tea. Overall, this investigation evidenced a beneficial mediation for the progression of lowering blood glucose with a combinatory extract of cinnamon, dietary onion, and tea, implicating their prospective as nutraceuticals that might ameliorate hyperglycemia in diabetes. PRACTICAL APPLICATIONS: Diabetes mellitus (DM), one of metabolic syndrome, attributes to risk factors like obesity, physical inactivity, ageing, life style, and genetic predisposition even with significant morbidity and mortality. DM is increasing and accounts for an estimated annual medical expenditure of US$ 827 billion worldwide. Therefore, maintaining blood glucose levels within the normal range is critical for preventing diabetes and its co-morbidities. The conventional antidiabetic agents are known to mitigate the symptoms of diabetes; nevertheless, they may also cause adverse or side effects. In an effort to design novel and well-tolerated solutions to halt the progression of DM, however evidence-base is extremely limited regarding the efficacy of polyherbal dietary supplement individual herbs for the management of glycemia. In this investigation evidenced a beneficial mediation for the progression of lowering blood glucose with a combinatory extract of cinnamon, dietary onion, and tea, implicating their prospective as nutraceuticals that might ameliorate hyperglycemia in diabetes.

Oral Nano Drug Delivery Systems for the Treatment of Type 2 Diabetes Mellitus: An Available Administration Strategy for Antidiabetic Phytocompounds

In view of the worldwide serious health threat of type 2 diabetes mellitus (T2DM), natural sources of chemotherapies have been corroborated as the promising alternatives, with the excellent antidiabetic activities, bio-safety, and more cost-effective properties. However, their clinical application is somewhat limited, because of the poor solubility, instability in the gastrointestinal tract (GIT), low bioavailability, and so on. Nowadays, to develop nanoscaled systems has become a prominent strategy to improve the drug delivery of phytochemicals. In this review, we primarily summarized the intervention mechanisms of phytocompounds against T2DM and presented the recent advances in various nanosystems of antidiabetic phytocompounds. Selected nanosystems were grouped depending on their classification and structures, including polymeric NPs, lipid-based nanosystems, vesicular systems, inorganic nanocarriers, and so on. Based on this review, the state-of-the-art nanosystems for phytocompounds in T2DM treatment have been presented, suggesting the preponderance and potential of nanotechnologies.

Catechins within the Biopolymer Matrix-Design Concepts and Bioactivity Prospects

Epidemiological studies and clinical investigations proposed that catechins extracts alone may not provide a sufficient level of bioactivities and promising therapeutic effects to achieve health benefits due to a number of constraints related to poor oral absorption, limited bioavailability, sensitivity to oxidation, etc. Modern scientific studies have reported numerous techniques for the design of micro- and nano-bio-delivery systems as novel and promising strategies to overcome these obstacles and to enhance catechins' therapeutic activity. The objective assessment of their benefits, however, requires a critical comparative estimation of the advantages and disadvantages of the designed catechins-biocarrier systems, their biological activities and safety administration aspects. In this respect, the present review objectively outlines, compares and assesses the recent advances related to newly developed design concepts of catechins' encapsulation into various biopolymer carriers and their release behaviour, with a special emphasis on the specific physiological biofunctionalities of the innovative bioflavonoid/biopolymer delivery systems.

Controlling Particle Size and Release Kinetics in the Sustained Delivery of Oral Antibiotics Using pH-Independent Mucoadhesive Polymers

Copolymers synthesized from acrylic acid and methacrylic acid used as gastroprotective and mucoadhesive enteric coatings have been used to prepare micro- (∼2 μm), submicro- (∼200 nm), and nanoparticles (∼20 nm) containing rifampicin (Rif) to obtain time-controlled drug release kinetics. Different particle sizes and drug release kinetics have been obtained using different synthesis conditions and fabrication techniques including the use of an electrosprayer and an interdigital microfabricated micromixer. The antimicrobial action of the encapsulated Rif has been demonstrated against Staphylococcus aureus ATCC 25923 and compared with the effect of the equivalent dose of the free macrolide antibiotic. At low concentrations, the encapsulated antibiotic showed superior antimicrobial activity than the free drug. The stability of the developed particles has been evaluated in vitro under simulated gastric and intestinal conditions. At the concentrations tested, a reduced cytotoxicity against different human cell lines was observed after analyzing their subcytotoxic doses and the influence on their cell cycle by flow cytometry. Drug release kinetics can be tuned by adjusting particle sizes, and it would be possible to reach the minimum inhibitory concentration or the minimum bactericidal concentration at different time points depending on the medical needs.

Identifying potential active components of walnut leaf that action diabetes mellitus through integration of UHPLC-Q-Orbitrap HRMS and network pharmacology analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Walnut leaf (WL) is a hypoglycemic herbal medication with blood glucose-lowering activity that can affect diabetes mellitus (DM). However, the active components of WL and the mechanisms by which these compounds affect DM are unclear.

AIM OF STUDY

This study aimed to determine these effective ingredients and elucidate the potential mechanisms by which they affect DM via ultra-high performance liquid chromatography-hybrid quadrupole-Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) coupled with network pharmacology analysis.

MATERIALS AND METHODS

First, UHPLC-Q-Orbitrap HRMS was utilized to identify components of WL. Second, the putative targets of the components were identified and predicted based on chemical similarity and online databases. Third, the key candidate targets and potential active components were identified through topological analysis of a component-disease target interaction network. Finally, interactions between active components and therapeutic targets were confirmed by molecular docking analysis.

RESULTS

One hundred and thirty components were identified in WL, among which 38 were considered potentially bioactive, as they showed hypoglycemic effects. Among these 38, 8 key active components possessed high similarities and shared 4 targets with approved drugs. These findings were confirmed by molecular docking analysis.

CONCLUSION

The approach combining UHPLC-Q-Orbitrap HRMS with network pharmacology analysis is a rapid and effective tool to identify potentially bioactive constituents in medicinal plants and prescriptions.

The Exploration of Natural Compounds for Anti-Diabetes from Distinctive Species Garcinia linii with Comprehensive Review of the Garcinia Family

Approximately 400 Garcinia species are distributed around the world. Previous studies have reported the extracts from bark, seed, fruits, peels, leaves, and stems of Garcinia mangostana, G. xanthochymus, and G. cambogia that were used to treat adipogenesis, inflammation, obesity, cancer, cardiovascular diseases, and diabetes. Moreover, the hypoglycemic effects and underlined actions of different species such as G. kola, G. pedunculata, and G. prainiana have been elucidated. However, the anti-hyperglycemia of G. linii remains to be verified in this aspect. In this article, the published literature was collected and reviewed based on the medicinal characteristics of the species Garcinia, particularly in diabetic care to deliberate the known constituents from Garcinia and further focus on and isolate new compounds of G. linii (Taiwan distinctive species) on various hypoglycemic targets including α-amylase, α-glucosidase, 5'-adenosine monophosphate-activated protein kinase (AMPK), insulin receptor kinase, peroxisome proliferator-activated receptor gamma (PPARγ), and dipeptidyl peptidase-4 (DPP-4) via the molecular docking approach with Gold program to explore the potential candidates for anti-diabetic treatments. Accordingly, benzopyrans and triterpenes are postulated to be the active components in G. linii for mediating blood glucose. To further validate the potency of those active components, in vitro enzymatic and cellular function assays with in vivo animal efficacy experiments need to be performed in the near future.