Antidiabetic activity of aqueous stem bark extract of Annickia polycarpa in alloxan-induced diabetic mice

Preparation, in vitro and in vivo evaluation of a novel mitiglinide microemulsions

This study aimed to prepare an o/w mitiglinide microemulsion (MTGME) to improve the drug solubility and bioavailability. The formulation of o/w MTGME was optimized by the solubility study of drug, pseudo-ternary phase diagram and Box-Behnken design successively. MTGME was characterized by dynamic laser light scattering (DLS), zeta potential and transmission electron microscopy (TEM), moreover, the storage stability, pharmacodynamics and pharmacokinetics were investigated. The optimal prescription for MTGME consisted of Maisine 35-1 (oil), Cremophor EL (surfactant) and propylene glycol (PG, cosurfactant). MTGME with a spherical dimension of 58.1 ± 5.86 nm was stable when stored at 4 °C for 3 months. The blood glucose levers (BGL) of diabetic mice were uniformly and significantly decreased by intragastric (i.g.) administration of 1-4 mg/kg MTGME, in which BGL (i.g. 4 mg/kg MTGME) was reduced by 69% during 24 h. The pharmacokinetics study of MTGME (i.g., 20 mg/kg) in Wistar rats showed higher plasma drug concentration (Cmax, 2.9 folds), larger area under curve (AUC, 4.6 folds) and oral bioavailability than those of MTG suspensions. Generally, the MTGME (o/w) showed good effect on controlling hyperglycemia. Therefore, microemulsion can be used as an effective oral drug delivery system to improve the bioavailability of MTG.

Radical oxygen species: an important breakthrough point for botanical drugs to regulate oxidative stress and treat the disorder of glycolipid metabolism

Background: The incidence of glycolipid metabolic diseases is extremely high worldwide, which greatly hinders people's life expectancy and patients' quality of life. Oxidative stress (OS) aggravates the development of diseases in glycolipid metabolism. Radical oxygen species (ROS) is a key factor in the signal transduction of OS, which can regulate cell apoptosis and contribute to inflammation. Currently, chemotherapies are the main method to treat disorders of glycolipid metabolism, but this can lead to drug resistance and damage to normal organs. Botanical drugs are an important source of new drugs. They are widely found in nature with availability, high practicality, and low cost. There is increasing evidence that herbal medicine has definite therapeutic effects on glycolipid metabolic diseases. Objective: This study aims to provide a valuable method for the treatment of glycolipid metabolic diseases with botanical drugs from the perspective of ROS regulation by botanical drugs and to further promote the development of effective drugs for the clinical treatment of glycolipid metabolic diseases. Methods: Using herb*, plant medicine, Chinese herbal medicine, phytochemicals, natural medicine, phytomedicine, plant extract, botanical drug, ROS, oxygen free radicals, oxygen radical, oxidizing agent, glucose and lipid metabolism, saccharometabolism, glycometabolism, lipid metabolism, blood glucose, lipoprotein, triglyceride, fatty liver, atherosclerosis, obesity, diabetes, dysglycemia, NAFLD, and DM as keywords or subject terms, relevant literature was retrieved from Web of Science and PubMed databases from 2013 to 2022 and was summarized. Results: Botanical drugs can regulate ROS by regulating mitochondrial function, endoplasmic reticulum, phosphatidylinositol 3 kinase (PI3K)/protein kinase B (AKT), erythroid 2-related factor 2 (Nrf-2), nuclear factor κB (NF-κB), and other signaling pathways to improve OS and treat glucolipid metabolic diseases. Conclusion: The regulation of ROS by botanical drugs is multi-mechanism and multifaceted. Both cell studies and animal experiments have demonstrated the effectiveness of botanical drugs in the treatment of glycolipid metabolic diseases by regulating ROS. However, studies on safety need to be further improved, and more studies are needed to support the clinical application of botanical drugs.

Ranunculus ternatus Thunb extract attenuates renal fibrosis of diabetic nephropathy via inhibiting SMYD2

CONTEXT

Ranunculus ternatus Thunb (Ranunculaceae), (RTT) is used clinically for the treatment of tuberculosis or as tumour adjuvant therapy, but its potential effect on diabetic nephropathy (DN) has not been studied.

OBJECTIVE

To investigate the effect of RTT extract in renal fibrosis of DN.

MATERIALS AND METHODS

C57BL/6 mice were randomly divided into four groups (n = 12). Diabetes mellitus (DM) mice were induced by streptozotocin (STZ, 55 mg/kg/day) for five consecutive days and treated by RTT extract (2 g/kg). Afterward, blood glucose, HE and Masson staining were assayed. The expression levels of Vimentin, ɑ-SMA, TNF-ɑ, NF-κB p-p65, NF-κB p65, SMYD2, H3K36me3, H3K4me3 were determined by western blots. Firbronectin was respectively assayed by western blot and immunofluorescent staining.

RESULTS

RTT extract significantly ameliorated renal injury and renal fibrosis in the renal tissue of STZ-induced diabetic mice as demonstrated by the decreased expression level of Fibronectin (65%), Vimentin and α-SMA (75% & 53%). In addition, the levels of TNF-α (57%), NF-κB p-p65 and NF-κB p65 (35% & 25%) were elevated in the DN mice. Importantly, these were alleviated after RTT extract treatment. Moreover, we observed that the protein levels of SMYD2 (30%), H3K36me3 and H3K4me3 (53% & 75%) were reduced in DN mice after treatment with RTT extract.

DISCUSSION AND CONCLUSIONS

RTT extract mediates antifibrotic effects and anti-inflammatory responses in STZ-induced DN mainly through suppressing SMYD2 activation and H3K36me3 and H3K4me3 protein expression. RTT extract might have therapeutic potential against high glucose-induced nephropathy.

Annickia polycarpa extract attenuates inflammation, neutrophil recruitment, and colon damage during colitis

Inflammatory bowel diseases (IBD) including Crohn's disease (CD) and ulcerative colitis (UC) are complex inflammatory disorders of the digestive tract. Dysfunctional intestinal epithelial barrier, uncontrolled neutrophil recruitment into the colon, and oxidative stress are major features of IBD. IBD cannot be cured, but symptoms can be alleviated with anti-inflammatory drugs, which often show adverse effects. Thus, safer alternative treatment options are needed. Given the known anti-inflammatory properties of Annickia polycarpa extract (APE), we hypothesized that APE improves the outcome of the inflammatory response during colitis. We assessed APE effects on colon histology, epithelial barrier function and neutrophil recruitment during DSS-induced colitis in mice treated with APE. APE treatment significantly reduced the disease activity index and prevented DSS-induced colon damage as evidenced by reduced colon shortening, ulcerations, crypt dysplasia, edema formation, and leukocyte infiltration. Expression of the pro-inflammatory cytokines TNF-α, IL-6, and IL-1β were significantly diminished in APE-treated mice. Importantly, APE administration reduced neutrophil infiltration into the lamina propria leading to reduced oxidative stress, tight junction disruption and epithelial permeability in the colon. Thus, we propose APE as additional treatment strategy to attenuate colitis symptoms and enhance life quality of individuals with IBD.

Echinops spinosus effect against diabetes and its hepatorenal complications: total extract and flavonoids fraction

The perennial plant Echinops spinosus (ES) grows in the Hail area of Saudi Arabia, and its traditional formulations are often employed in folk medicine. The goal of this study is to identify the active components present in Hail Echinops spinosus and to investigate the anti-diabetic properties of both ES total extract (ESTE) and its high flavonoids fraction (ESHFF) in experimental diabetes induced by streptozotocin (STZ) injection in rats. Forty-two rats were divided into six groups. Diabetes was induced using STZ (55 mg/kg). Seven days after STZ administration, the diabetic animals were treated daily with ESTE, ESHFF, or metformin (MET) as a standard anti-diabetic drug for 28 days. Blood and tissues samples were collected for biochemical, molecular, and histological investigations. Both ESTE and ESHFF demonstrated anti-diabetic properties, as evidenced by lowering glucose levels and increasing the levels of insulin, insulin receptor expression rate, and glycogen synthesis. Additionally, ESTE as well as ESHFF alleviated diabetic complications in the kidneys and liver by decreasing oxidative stress, modulating inflammatory mediators, and suppressing the apoptotic cascade along with correcting diabetic dyslipidemia. It could be deduced that Hail ES extracts could play a role in the treatment of type 2 diabetes and diabetes-related lesions as well as oxidative damage in hepatic and renal tissues.

Exploring of novel 4-hydroxy-2H-benzo[e][1,2]thiazine-3-carbohydrazide 1,1-dioxide derivative as a dual inhibitor of α-glucosidase and α-amylase: Molecular docking, biochemical, enzyme kinetic and in-vivo mouse model study

Diabetes mellitus (DM) is a metabolic disorder that leads to hyperglycemia due to improper insulin secretion. The study aims to investigate the anti-diabetic potential of benzothiazine derivatives. Molecular docking and Molecular Dynamics simulation study revealed that Compound S6 (4-hydroxy-2H-benzo[e][1,2]thiazine-3-carbohydrazide 1,1-dioxide) and S7 (4-Hydroxy-2-methyl-2H-1,2-benzothiazine-3-carbohydrazide 1,1-dioxide) had less conformational changes during MD simulation analysis at 100 ns. Compound S6 and S7 showed potent activity with IC50 values of 5.93 μM, 6.91 μM and 75.17, 29.10 μM for α-glucosidase and α-amylase respectively and competitive type of inhibition was observed during enzyme kinetic study with a low value of Ki and Ki' for α-glucosidase and α-amylase, respectively. S6 has the lowest Ki (0.0736) and Ki' (-0.0982) for α-glucosidase. Furthermore, in vivo studies were carried out to distinguish the effects of the drug on the body. Histology analysis on mice model showed that compound S6 has a low necrosis rate in the liver, kidney, and pancreas compared to S7. Biochemical results of S6 revealed lower sugar level (112 mg/dL), increase insulin secretion (23, 25 μM/L), and low level of cholesterol (80, 85 mg/dL) and creatinine (1.6, 1.4 mg/dL). The results conclude that compound S6 is a new anti-diabetic agent that minimizes hyperglycemia complications.

Evaluation of pancreatic regeneration activity of Tephrosia purpurea leaves in rats with streptozotocin-induced diabetes

Background and aim

Flavonoid rich plant Tephrosia purpurea (T. purpurea), commonly known as Sarpunkha has been used in traditional systems of medicine to treat diabetes mellitus. However, its effectiveness in promoting regeneration of pancreas in diabetes has not been investigated. Therefore, the present study was undertaken to evaluate pancreatic β-cells regeneration, antioxidant and antihyperlipidemic potentials of T. purpurea leaves extract, its fractions and main constituent Rutin in diabetic rats.

Experimental procedure

The leaves extract and its fractions were first screened for acute and sub-chronic antidiabetic activity in a dose range of 250–500 mg/kg orally. Further, fractions with potent antidiabetic activity were screened for pancreatic β-cells regeneration activity using histopathological studies and morphometric analysis, which was followed by estimation of biochemical parameters.

Results and conclusion

The most significant antidiabetic, pancreatic regeneration and antihyperlipidemic activity was exhibited by n-butanol soluble fraction of ethanol extract at the dose level of 500 mg/kg. Histopathology revealed that treatment with this fraction improved the β-cell granulation of islets and prevented the β-cells damage which was further confirmed by morphometric analysis. Thus, the present study validated the traditional use of T. purpurea plant in the treatment of diabetes, which might be attributed to pancreatic β-cells regeneration potential of its active constituent Rutin.

Taxonomy (classification by EVISE)

Traditional Medicine; Metabolic Disorder; Experimental Design; Cell Regeneration and Histopathology.

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Polyphenol rich extract possesses potent in vitro antioxidant activity.

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Extract and its fractions are having pancreatic regeneration potential in STZ induced diabetic model.

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Histopathological study of the pancreas extract and fraction treated diabetic rats showed islets expansion and decreased fatty infiltrate of the islets.

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Study validates the use of plant in treatment of diabetes.

Herbal Medicines Targeting the Improved β-Cell Functions and β-Cell Regeneration for the Management of Diabetes Mellitus

There is an increasing trend of investigating natural bioactive compounds targeting pancreatic β-cells for the prevention/treatment of diabetes mellitus (DM). With the exploration of multiple mechanisms by which β-cells involve in the pathogenesis of DM, herbal medicines are gaining attention due to their multitasking ability as evidenced by traditional medicine practices. This review attempts to summarize herbal medicines with the potential for improvement of β-cell functions and regeneration as scientifically proven by in vivo/in vitro investigations. Furthermore, attempts have been made to identify the mechanisms of improving the function and regeneration of β-cells by herbal medicines. Relevant data published from January 2009 to March 2020 were collected by searching electronic databases “PubMed,” “ScienceDirect,” and “Google Scholar” and studied for this review. Single herbal extracts, polyherbal mixtures, and isolated compounds derived from approximately 110 medicinal plants belonging to 51 different plant families had been investigated in recent years and found to be targeting β-cells. Many herbal medicines showed improvement of β-cell function as observed through homeostatic model assessment-β-cell function (HOMA-β). Pancreatic β-cell regeneration as observed in histopathological and immunohistochemical studies in terms of increase of size and number of functional β-cells was also prominent. Increasing β-cell mass via expression of genes/proteins related to antiapoptotic actions and β-cell neogenesis/proliferation, increasing glucose-stimulated insulin secretion via activating glucose transporter-2 (GLUT-2) receptors, and/or increasing intracellular Ca²⁺ levels were observed upon treatment of some herbal medicines. Some herbal medicines acted on various insulin signaling pathways. Furthermore, many herbal medicines showed protective effects on β-cells via reduction of oxidative stress and inflammation. However, there are many unexplored avenues. Thus, further investigations are warranted in elucidating mechanisms of improving β-cell function and mass by herbal medicines, their structure-activity relationship (SAR), and toxicities of these herbal medicines.

Does Rabeprazole Sodium Alleviate the Anti-diabetic Activity of Linagliptin? Drug-Drug Interaction Analysis by In vitro and In vivo Methods

Drug interaction has turned into the preeminent regarding issues for a prescriber during polypharmacy. The foremost objective of this research was to form a complex between linagliptin and rabeprazole sodium by in vitro interactions. The interactions between the drugs have been examined by monitoring some chromatographic and spectroscopic analyses viz. TLC, HPLC, FT-IR, UV, Job's plot, conductometric titrations, and Ardon's spectrophotometric strategy. Rabeprazole sodium formed a stable complex with linagliptin, which was ensured from the insight of these analytical data. The developed complex's bright spot was clearly watched in the TLC plate. The retention time (R_t) of the formed complex was 5.303 min, where the R_t were 3.364 and 3.103 min for linagliptin and rabeprazole sodium, respectively, in HPLC chromatograms. In FT-IR and UV spectra of the formed complex revealed some disappearance of characteristic peaks that affirmed the complexation. All of the variations of the spectrophotometric and chromatographic properties from the antecedent drugs indicated the drug-drug interaction. Another crucial fact for the experimental aim was to affirm the assumed drug interaction by in vivo model examination. The assessment of anti-diabetic property on alloxan-induced Swiss albino mice proved significant in vivo interaction between the drugs. It was outlined from the animal study that the hypoglycemic activity of linagliptin might be significantly affected due to the complex formation of the drug with a proton pump inhibitor (PPI). Nonetheless, it is the primary outcome of the interaction, which recommends the bigger in vivo study or clinical monitoring on the human model.