In vitro alpha-amylase inhibition and in vivo antioxidant potential of Momordica dioica seeds in streptozotocin-induced oxidative stress in diabetic rats

Effect of Hibiscus sabdariffa L. leaf flavonoid-rich extract on Nrf-2 and HO-1 pathways in liver damage of streptozotocin-induced diabetic rats

This study investigated the effects of flavonoid-rich extract from Hibiscus sabdariffa L. (Malvaceae) leaves on liver damage in streptozotocin-induced diabetic rats by evaluating various biochemical parameters, including the molecular gene expressions of Nrf-2 and HO-1 as well as histological parameters. The extract was found to significantly reduce liver damage, as evidenced by lower levels of fragmented DNA and protein carbonyl concentrations. Oxidative stress markers, including malondialdehyde (MDA) level, were also significantly (p < 0.05) decreased, while antioxidant biomarkers, like reduced glutathione (GSH), catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione-S-transferase (GST) were enhanced. Additionally, the extract improved the activities of key liver enzymes, including phosphatases and transaminases, and increased albumin levels. Importantly, the study demonstrated that H. sabdariffa extract effectively regulated the expression of Nrf-2 and HO-1, suggesting a significant role in mitigating liver damage. These findings highlight its potential as a therapeutic agent for liver protection in diabetic conditions.

Evaluation of <i>Saussurea lappa</i> on Oxidative Stress and Cognition in Aluminium-induced Alzheimer’s Disease Rats

Background: Oxidative stress and neurodegenerative illnesses, such as Alzheimer's disease (AD), are closely associated. There has been a lot of thought put into finding medicinal plants with nootropic properties to slow the onset and course of AD. Objective: The study aimed to evaluate the methanolic extract of Saussurea lappa clarke (MESC) on oxidative stress and cognitive ability induced by aluminium exposure.  Methods: Wistar albino rats were chosen for the study. About 30 animals were selected and grouped into 5 with 6 animals in each group. Group I served as control, group II served as disease induced (Aluminium-induced), group III, IV and V were administered with standard drug – Donepezil Hcl, and MESC at two doses – 200 and 400 mg/kg. The behavioural studies were examined by using certain apparatus like Passive Avoidance (PA) test, Elevated Plus Maze, Y- Maze and Actophotometer. Determination of anti-oxidant enzymes – Catalase (CAT) and thiobarbituric acid reactive substances (TBARS) along with acetylcholinesterase (AChE) levels which was done in rat’s brain homogenate. Results: In the PA test, administration of MESC at doses of 200 and 400 mg/kg significantly (**p< 0.01) lengthened step-through latency (STL) in rats on day 30 compared to the positive control group. Animals at MESC (200 & 400 mg/kg) showed noticeably higher memory retention (MR) rates as compared to the disease-control group. Additionally, administration of MESC (200 and 400 mg/kg) significantly (**p< 0.01) raised CAT and declined the concentration of TBARS. AChE concentration was significantly (**p< 0.01) reduced at the dose of MESC at 200 and 400 mg/kg as compared to the positive control group. Conclusion: The present study showed that MESC had a strong nootropic effect on brain antioxidant indicators and cognitive function in rats exposed to aluminium-induced oxidative stress and cognitive impairment. These findings may be investigated in the treatment of neurodegenerative diseases, including AD.

Experimental approaches for induction of diabetes mellitus and assessment of antidiabetic activity: An in vitro and in vivo methodological review

BACKGROUND

Diabetes mellitus poses a global health challenge, driving the need for innovative therapeutic solutions. Experimental methods play a crucial role in evaluating the efficacy of potential antidiabetic drugs, both in vitro and in vivo. Yet concerns about reproducibility persist, necessitating comprehensive reviews.

OBJECTIVES

This review aims to outline experimental approaches for inducing diabetes and evaluating antidiabetic activity, synthesizing data from authoritative sources and academic literature.

METHODS

We conducted a systematic search of prominent databases, including PubMed, ScienceDirect, and Scopus, to identify relevant articles spanning from 1943 to the present. A total of 132 articles were selected for inclusion in this review, focusing on in vitro and in vivo experimental validations of antidiabetic treatments.

RESULTS

Our review highlights the diverse array of experimental methods employed for inducing diabetes mellitus and evaluating antidiabetic interventions. From cell culture assays to animal models, researchers have employed various techniques to study the effectiveness of novel therapeutic agents.

CONCLUSION

This review provides a comprehensive guide to experimental approaches for assessing antidiabetic activity. By synthesizing data from a range of sources, we offer valuable insights into the current methodologies used in diabetes research. Standardizing protocols and enhancing reproducibility are critical for advancing effective antidiabetic treatments.

Mesoporous silica and alumina nanoparticles to improve drug delivery of pioglitazone on diabetic type 1 nephropathy in rats

Background and purpose

Diabetic nephropathy leads to end-stage renal disease. The present study aimed to evaluate the prophylactic effect of pioglitazone-loaded mesoporous silica and alumina scaffold on renal function and the underlying mechanisms in streptozotocin-induced diabetic rats.

Experimental approach

The mesoporous nanoparticles were synthesized by chemical methods from tetraethylorthosilicate and aluminum isopropoxide and characterized by Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. The soaking method was applied to load pioglitazone into the mesoporous silica and alumina. Subsequently, the most capable formulation was evaluated for lipid profile, blood glucose, renal function biomarkers, malondialdehyde, and kidney histopathological changes in diabetic rats.

Findings/Results

Pioglitazone loaded in the mesoporous included a superior release of about 80%. No interaction was observed in Fourier transform infrared spectroscopy and X-ray diffraction was shown crystalline. Scanning electron microscopy showed the size of the nanometer in the range of 100 - 300 nm. Mesoporous silica containing the drug significantly decreased urinary parameters, triglycerides, low-density lipoprotein, blood urea nitrogen, blood glucose, malondialdehyde, and creatinine. In addition, it showed increased high-density lipoprotein, significantly. The renal histopathological changes indicated improvement compared with the untreated diabetic group.

Conclusion and implications

It was concluded that the mesoporous was potent to serve as a promising drug carrier and a platform aimed at the delivery of poorly water-soluble drugs for improving oral bioavailability. Furthermore, it has the potential to provide a beneficial effect on the changes in diabetic parameters.

Unveiling the breadmaking transformation: Structural and functional insights into Arabinoxylan

To understand the changes in arabinoxylan (AX) during breadmaking, multi-step enzyme digestion was conducted to re-extract arabinoxylan (AX-B) from AX-fortified bread. Their structural changes were compared using HPSEC, HPAEC, FT-IR, methylation analysis, and 1H NMR analysis; their properties changes in terms of enzymatic inhibition activities and in vitro fermentability against gut microbiota were also compared. Results showed that AX-B contained a higher portion of covalently linked protein while the molecular weight was reduced significantly after breadmaking process (from 677.1 kDa to 15.6 kDa); the structural complexity of AX-B in terms of the degree of branching was increased; the inhibition activity against α-amylase (76.81 % vs 73.89 % at 4 mg/mL) and α-glucosidase (64.43 % vs 58.08 % at 4 mg/mL) was improved; the AX-B group produced a higher short-chain fatty acids concentration than AX (54.68 ± 7.86 mmol/L vs 44.03 ± 4.10 mmol/L). This study provides novel knowledge regarding the structural and properties changes of arabinoxylan throughout breadmaking, which help to predict the health benefits of fibre-fortified bread and achieve precision nutrition.

Explicit mechanistic insights of Prosopis juliflora extract in streptozotocin-induced diabetic rats at the molecular level

Background

The Ancient system of medicine showed the limelight on the use of herbal remedies and was found to possess minimal side effects and acceptable therapeutic outcomes. In this context, Prosopis juliflora gained importance in managing chronic diseases such as cancer, dermatological diseases, and chronic inflammatory disorders. Hence, P. juliflora was selected for further investigation associated with diabetes and inflammation.

Aim

The present study aimed to evaluate the anti-diabetic activity in chemically induced experimental rats and explore the nature of phytocomponents that may produce this activity.

Methods

Experimentally, diabetes was induced by a single administration of streptozotocin at 50 mg/kg intraperitoneally in Wistar rats. The animals were treated orally with P. juliflora at low and high doses (200 and 400 mg/kg) for 10 days. Blood collected from the retro-orbital plexus was analyzed for parameters like blood glucose levels, insulin, adiponectin, Keap1 and Nrf2. PPAR-γ, AMPK and GLUT 2 levels were analyzed in the pancreatic tissue. Besides, at the end of the experiment, animals were sacrificed, and the pancreatic tissue sections were subjected for histopathological, morphometrical and immune histochemical exploration. The phytochemical composition of the plant was investigated by GC-MS.

Results

The administration of P. juliflora higher dose showed a significant decrease (**p< 0.001) in blood glucose levels with a rise in adiponectin, PPARγ, Keap1, Nrf2, Glut 2, and AMPK significantly (**p< 0.001). The inflammatory cytokine TNFα was also estimated and was found to be lowered significantly (**p< 0.001) in test drug-treated animals. Furthermore, in the pancreatic tissue, the number of Islets, the area, and the number of β-cells were improved significantly with the sub-chronic treatment of P. juliflora extract. The structure and function of β-cells were also revamped.

Conclusion

The study results demonstrated a significant effect of P. juliflora on glycemic status, inflammatory condition, and the architecture of pancreatic tissue. In the identification and isolation process by GC MS, it was noticed that P. juliflora contained few phytochemical constituents from which it might be considered a promising drug for type 2 diabetes mellitus.

Bioanalytical method development for momordicinin and its application to long-term pharmacokinetics in diabetic rats

OBJECTIVE

To develop and validate bioanalytical RP-HPLC method to evaluate pharmacokinetics and tissue distribution pattern of momordicinin (MRN).

SIGNIFICANCE

MRN is one of the major cucurbitane triterpenoid found in Momordica charantia Linn (MC). However, MRN has not been explored for its pharmacokinetic profile, tissue distribution, and stability in order to establish it as an antidiabetic agent.

METHODS

In 28 days pharmacokinetic study, 54 diabetic male wistar rats were divided into three different groups and administered with 25, 50, and 100 mg/kg MRN orally. The blood samples were collected at 1, 7, 14, 21, and 28th day of the treatment and plasma quantification of MRN was done by validated RP-HPLC method. The rats were sacrificed at end of the study for tissue distribution.

RESULTS

The developed method was successfully applied to investigate pharmacokinetic profile of MRN. In pharmacokinetic analysis, the C_max for 25, 50, and 100 mg/kg was found to be 8.412, 10.443, and 11.829 µg/mL respectively suggesting the dose dependent activity. The maximum plasma concentration was achieved at 2 h for all doses. MRN showed major distribution in liver followed by kidney, spleen, and pancreas.

CONCLUSION

The newly developed and validated method was used to assay MRN in plasma as well as in tissues to evaluate pharmacokinetics of the drug for the first time. Undoubtedly, these findings can be taken into consideration while concluding its therapeutic effects after oral administration.

Nutritional Composition, Total Phenolic Content, Antioxidant and α-Amylase Inhibitory Activities of Different Fractions of Selected Wild Edible Plants

Wild plants are considered the richest source of essential nutrients and other beneficial phytochemicals. Hence, the objective of this study was to evaluate the nutritional composition, antioxidant- and α-amylase inhibition activities of leaves and roots of selected Bangladeshi wild plants. These wild plants were found to have high fiber (13.78-22.26 g/100 g), protein (7.08-21.56 g/100 g) and ash (8.21-21.43 g/100 g) contents. The total phenolic and total flavonoid contents were significantly higher in the leaves than the roots. Additionally, antioxidant activity was evaluated using ferric-reducing antioxidant power, 2, 2-diphenyl-1-picrylhydrazyl radical (DPPH) and trolox equivalent antioxidant capacity assays and was strongly correlated with phenolic compounds. The leaf extracts of the selected plants also exhibited potent α-amylase inhibition (~71%) and were significantly higher than their root counterparts. Thus, the study findings concluded that the investigated plants were good sources of fiber, protein, mineral, natural antioxidant compounds and α-amylase inhibitors, and their increased intake could provide health benefits. The principal component analysis (PCA) of analyzed variables divided the samples into three clear groups, and the first two principal components accounted for 86.05% of the total data set variance.

Identification of Bioactive Peptides with α-Amylase Inhibitory Potential from Enzymatic Protein Hydrolysates of Red Seaweed (Porphyra spp)

Inhibition of α-amylase enzyme is one therapeutic approach in lowering glucose level in the blood to manage diabetes mellitus. In this study α-amylase inhibitory peptides were identified from proteolytic enzymes hydrolysates of red seaweed laver ( Porphyra species) using consecutive chromatographic techniques. In the resultant fractions from RP-HPLC (D₁-₁₀), D₂ inhibited α-amylase activity (88.67 ± 1.05%) significantly ( p ≤ 0.5) at 1 mg/mL protein concentration. A mass spectrometry (ESI-Q-TOF- MS) analysis was used to identify peptides from this fraction. Two novel peptides were identified as Gly-Gly-Ser-Lys and Glu-Leu-Ser. To validate their α-amylase inhibitory activity, these peptides were synthesized chemically. The peptides were demonstrated inhibitory activity at IC₅₀ value: 2.58 ± 0.08 mM (Gly-Gly-Ser-Lys) and 2.62 ± 0.05 mM (Glu-Leu-Ser). The inhibitory kinetics revealed that these peptides exhibited noncompetitive binding mode. Thus, laver can be a potential source of novel ingredients in food and pharmaceuticals in diabetes mellitus management.

An improved micropropagation system, ex vitro rooting and validation of genetic homogeneity in wild female Momordica dioica: an underutilized nutraceutical vegetable crop

Momordica dioica Roxb. ex Willd., is a perennial and dioecious (2n = 28) plant of family Cucurbitaceae. Conventional methods of propagation through seeds, stem cuttings and rhizomatous/tuberous roots are inadequate for its mass cultivation as a vegetable crop. This paper reports an improved and efficient micropropagation method for wild female M. dioica using nodal explants. Shoot amplification was achieved using subculturing of in vitro raised shoots on MS medium supplemented with various concentrations of 6-benzylaminopurine (BAP) alone or in combination with indole-3-acetic acid (IAA). The maximum number of shoots (45.30 ± 3.83) with an average length 6.52 ± 0.89 cm were differentiated on MS medium containing 0.5 mg L-1 BAP, 0.1 mg L-1 IAA and additives (50 mg L-1 ascorbic acid, 25 mg L-1 each of adenine sulphate, citric acid and l-arginine). The cloned shoots were rooted ex vitro. Each shoot treated with 250 mg L-1 IBA for 5 min produced 12.3 ± 1.33 with a mean length 5.4 ± 0.73 cm. More than 85% (46 plants) of ex vitro rooted plantlets were successfully hardened in a greenhouse with normal growth characteristics. In order to evaluate the genetic stability of micropropagated plants, the two PCR-based techniques, Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeats (ISSR) were used. The amplification patterns of the micropropagated and mother plant were monomorphic thus depicting genetic stability of the micropropagation system. This protocol could be effectively employed for the mass multiplication of wild female M. dioica, a popular summer vegetable crop.

Evaluation of the Cellular and Animal Models for the Study of Antioxidant Activity: A Review

The mechanisms of antioxidant activities of phytochemicals are highly complex, so various methods to study them have been developed. However, the diverse available methods show inconsistent results. Different stressors, cell models, and animal models have been used to evaluate the antioxidant properties of phytochemicals. However, the literature still lacks a summary of the effects of different stressors, cell models, and animal models on the evaluation of antioxidant activities. Therefore, the mechanisms of action of different oxidative stimuli and the characteristics of the available cell models and animal models are summarized in this review.