Evaluation of antidiabetic activity of bud and flower of Avaram Senna (Cassia auriculata L.) In high fat diet and streptozotocin induced diabetic rats

Antioxidative and anti-diabetic effects of Tapinanthus cordifolius leaf extract on high-fat diet and streptozotocin-induced type 2 diabetic rats

Type 2 diabetes mellitus (T2DM) remains a global health concern despite current treatment options. This study investigated the potential of Tapinanthus cordifolius (TC) leaf extract as a therapeutic agent for T2DM. T2DM was induced in rats using a high-fat diet and streptozotocin. Diabetic rats received daily oral administration of TC extract (200, 400, or 800 mg/kg) and metformin (400 mg/kg) or remained untreated for 21 days. Blood glucose levels, body weight, diabetic symptoms, oxidative stress markers, and gene expression of metabolic regulators were assessed. TC treatment significantly reduced blood glucose levels and restored body weight in diabetic rats, comparable to the effects of metformin. TC also increased antioxidant enzyme activities (SOD, GST, and CAT) and decreased lipid peroxidation in various tissues. Furthermore, TC upregulated gene expression of glucose transporter type 4 (GLUT-4) and adiponectin receptor 2 (ADIPOR-2) while downregulating pro-inflammatory cytokines TNF-α and IL-6. This study provides the first in vivo evidence supporting TC leaf extract's anti-diabetic and antioxidant efficacy. The findings suggest that TC holds promise as a natural therapeutic agent for managing T2DM through multiple mechanisms, including improved glycemic control, enhanced insulin sensitivity, and protection against oxidative stress and tissue damage. In conclusion, this study validates the ethnobotanical use of TC as an anti-diabetic agent. Further research is warranted to isolate the bioactive compounds responsible for these effects.

Diabetes Warriors from Heart Wood: Unveiling Dalbergin and Isoliquiritigenin from Dalbergia latifolia as Potential Antidiabetic Agents in-vitro and in-vivo

Diabetes mellitus is a serious and complex metabolic disorder characterized by hyperglycemia. In recent years natural products has gained much more interest by researchers as alternative sources for diabetes treatment. Though many potential agents are identified so far but their clinical utility is limited because of their adverse effects. Therefore, there is a keen interest in discovering natural compounds to treat diabetes efficiently with less side effects. Dalbergia latifolia is well explored because of its diverse pharmacological activities including diabetes. Therefore, the present research work aimed to identify and isolate the potential antidiabetic agents from the heart wood of Dalbergia latifolia. We successfully extracted DGN and ISG from the heartwood and evaluated their antidiabetic potential both in-vivo and in-vitro. Alpha amylase activity inhibition of ISG and DGN was found to be 99.05 ± 8.54% (IC50 = 0.6025 µg/mL) and 84.68 ± 5.2% (IC50 = 0.0216 µg/mL) respectively. Glucose uptake assay revealed DGN (158%) promoted maximum uptake than ISG (77%) over control. In vivo anti diabetic activity was evaluated by inducing diabetes in SD rats with the help of HFD and STZ (35 mg/kg body weight). After the continuous administration of DGN (5 mg/kg, 10 mg/kg) and ISG (5 mg/kg, 10 mg/kg) for 14 days, we observed the reduction in the blood glucose levels, body weight, total cholesterol, low density lipoprotein, very low-density lipoprotein, blood urea, serum creatinine, serum glutamate oxaloacetic transaminase, serum glutamate pyruvate transaminase and alkaline phosphatase levels than vehicle group indicates the potency of ISG and DGN against diabetes.

Influence of chitosan and hydroxyethyl cellulose modifications towards the design of cross-linked double networks hydrogel for diabetic wound healing

The wound dressings' lack of antioxidant and antibacterial properties, and delayed wound healing limit their use in wound treatment and management. Recent advances in dressing materials are aimed at improving the limitations discussed above. Therefore, the aim of this study includes the preparation and characterization of oxidized hydroxyethyl cellulose (OHEC) and ferulic acid-grafted chitosan (CS-FA) hydrogel loaded with green synthesized selenium nanoparticles (Se NPs) (OHEC-CS-FA-Se NPs named as nanohydrogel) for diabetic wound healing. The structure and properties of the hydrogel was characterized by FTIR, FE-SEM, HR-TEM, EDAX, UV-Vis spectrophotometry, XRD, DLS, zeta potential and rheological studies. The findings of these experiments demonstrate that nanohydrogel possesses a variety of outstanding qualities, including an optimal gel time, good swelling characteristics, a fair water retention rate, a good degradation rate, and strong mechanical stability. Nanohydrogel has been shown to have a synergistic impact by significantly increasing antioxidant activity by scavenging ABTS and DPPH radicals. The nanohydrogel's strong biocompatibility was confirmed by cytocompatibility testing using L929 mouse fibroblast cells. In addition, the wound healing potential of nanohydrogel was tested on L929 cells by an in vitro scratch assay and the nanohydrogel showed a wound closure rate of 100 % after 12 h. In addition to this study, nanohydrogel has demonstrated significant antimicrobial properties against human and wound infection causing pathogens such as Bacillus subtilis, methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, and Pseudomonas aeruginosa. In the animal model, almost complete diabetic wound healing was achieved on day 14 after application of the nanohydrogel. The results obtained indicate that the multifunctional bioactive nature of OHEC-CS-FA-Se NPs showed exceptional antioxidant and antibacterial potential for the treatment of infected and chronic wounds.

Gelatine nanoparticles encapsulating three edible plant extracts as potential nanonutraceutical agents against type 2 diabetes mellitus

AIM

To optimise, and characterise gelatine nanoparticles (GNPs) encapsulating plant extracts and evaluate the glucose-lowering potential.

METHODS

GNPs encapsulating plant extracts were prepared by desolvation method followed by adsorption. The GNPs were characterised by loading efficiency, loading capacity, particle size, zeta potential, SEM and FTIR. The glucose-lowering activity of GNPs was determined using oral glucose tolerance test in high-fat diet fed streptozotocin-induced Wistar rats.

RESULTS

Loading efficiency and capacity, particle mean diameter, and zeta potential of optimised GNPs 72.45 ± 13.03% w/w, 53.05 ± 26.16% w/w, 517 ± 48 nm and (-)23.43 ± 9.96 mV respectively. GNPs encapsulating aqueous extracts of C. grandis, S. auriculata, and ethanol 70% v/v extracts of M. koenigii showed glucose-lowering activity by 17.62%, 11.96% and 13.73% (p < 0.05) compared to the non-encapsulated extracts. FTIR analysis confirmed the encapsulation of phytoconstituents into GNPs. SEM imaging showed spherical GNPs (174 ± 46 nm).

CONCLUSION

GNPs encapsulating plant extracts show promising potential to be developed as nanonutraceuticals against diabetes.

Green synthesis of silver nanoparticles from Cassia Auriculata: Targeting antibacterial, antioxidant activity, and evaluation of their possible effects on saltwater microcrustacean, Artemia Nauplii (non-target organism)

Due to their huge surface area to volume ratio, metallic nanoparticles are becoming increasingly important in numerous spheres of life. Here, initially, we aimed to evaluate the potential use of Cassia auriculata (CA) extract to synthesize silver nanoparticles (AgNPs). Then, we evaluated its antimicrobial potential and antioxidant capacity, as well as performed in silico analysis, and investigated the possible non-toxic effect of AgNPs on Artemia nauplii. Fourier transform infrared (FTIR) spectroscopy, scanning and transmission electron microscopy (SEM/TEM), energy dispersive spectroscopy (EDX), X-ray diffraction (XRD), and dynamic light scattering (DLS) studies were used to characterize the biosynthesized AgNPs. Our data indicate that Bacillus cereus, Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus bacteria were susceptible to the biosynthesized AgNPs, whose effect was concentration-response. With a ZOI of 10 mm, the AgNPs were most efficient against gram-positive B. cereus bacteria at the highest concentration (75 μg/mL). The biosynthesized AgNPs (at 25 to 125 μg/mL) showed good antioxidant activity in the DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) and FRAP (ferric reducing antioxidant power) assays. Oleanolic acid from CA exhibited strong binding affinity and high binding energy to E. coli and B. cereus (-9.66 and - 9.74 kcal/mol) on in silico research. According to the comparative non-toxicity analysis, AgNPs, AgNO₃, and CA bark extract had the least toxic effects on A. nauplii, with respective mortality rates of 28.14, 32.26, and 38.42 %, respectively. In conclusion, the current work showed that AgNPs produced from CA bark could be a promising material for diverse applications.

A Review of Medicinal Plants with Renoprotective Activity in Diabetic Nephropathy Animal Models

Diabetic nephropathy (DN), also recognized as diabetic kidney disease, is a kidney malfunction caused by diabetes mellitus. A possible contributing factor to the onset of DN is hyperglycemia. Poorly regulated hyperglycemia can damage blood vessel clusters in the kidneys, leading to kidney damage. Its treatment is difficult and expensive because its causes are extremely complex and poorly understood. Extracts from medicinal plants can be an alternative treatment for DN. The bioactive content in medicinal plants inhibits the progression of DN. This work explores the renoprotective activity and possible mechanisms of various medicinal plant extracts administered to diabetic animal models. Research articles published from 2011 to 2022 were gathered from several databases including PubMed, Scopus, ProQuest, and ScienceDirect to ensure up-to-date findings. Results showed that medicinal plant extracts ameliorated the progression of DN via the reduction in oxidative stress and suppression of inflammation, advanced glycation end-product formation, cell apoptosis, and tissue injury-related protein expression.

Antioxidant and antidiabetic activities of a polyphenol rich extract obtained from Abelmoschus esculentus (okra) seeds using optimized conditions in microwave-assisted extraction (MAE)

Functional foods have gained popularity in recent decades. They are exploited for their bioactive compounds like polyphenols, which are highly demanded in cosmetic, pharmaceutical and nutraceutical industries. However, extractive techniques and conditions used up to recently are almost obsolete and must be optimized for higher efficiency. The current study aimed to evaluate the antidiabetic potential of an optimized extract of Abelmoschus esculentus (okra) seeds. The optimal conditions for extracting polyphenolic compounds from okra seeds were determined using Microwave Assisted Extraction (MAE). A Face Center Composite Design (FCCD) was used for optimization. Solvent/dry matter ratio, wavelength and time were considered while the response studied was the polyphenolic content. The extract obtained at optimal conditions was characterized using Thin Layer Chromatography (TLC) and Fourier Transform Infra-Red (FTIR) spectroscopy, then tested for its antioxidant, alpha amylase inhibitory and antidiabetic activities. Response Surface Methodology (RSM) permitted the determination of the optimal conditions for phenols extraction as: microwave power 330 W, with a solvent ratio of 97.04/1 mL/g for 9.5 min of extraction time. The optimized extract showed a phenolic content up to 86.37 ± 1.13 mg GAE/g containing quercetin and catechin as revealed by the TLC. Functional groups characteristic of polyphenols were identified on FTIR spectra, and the extract exhibited good in vitro antioxidant capacities with DPPH (2, 2-diphenyl-1-picrylhydrazyl) radical scavenging capacity and FRAP (Ferric Reducing Antioxidant Power Assay). An IC50 of 3.99 ± 0.15 μg/mL was obtained with the DPPH scavenging test. Alpha amylase inhibitory assay revealed that the optimized okra extract behaved as a non-competitive inhibitor of porcine pancreatic amylase with an IC50 of 484.17 ± 2.33 μg/mL. Antidiabetic activity of the extract was observed in streptozotocin-induced diabetic males Wistar rats, as shown by the fasting blood glucose levels, food intake, changes in body weight and serum lipid profile among others.

Antidiabetic and antihyperlipidemic effects of crude fractions and isolated compound from Striga orobanchioides Benth on streptozotocin induced diabetic rats

Background

Striga orobanchioides Benth is a traditionally used Ayurvedic medicinal plant for the treatment of diabetes. Scientific validation of the claim is studied in this research. The significant bioactivity of the plant components is obligatory for its use in medicine.

Objective

The present work is to extract bioactive fractions and chemicals, biological activity of the chemicals and to identify potentially bioactive compound(s) from ethanolic extract of the plant.

Materials and methods

Ethanolic extract of the authenticated plant was fractionated and subjected to in vitro and in vivo antidiabetic and antihyperlipidemic activity. In vitro α-amylase and α-glucosidase enzyme activity was carried out on digestive enzyme. Streptozotocin (STZ) induced diabetes mellitus in rats model was preferred for in vivo activity where antidiabetic parameters body weight, urine volume, blood glucose level, glycosylated hemoglobin, serum insulin, liver glycogen and lipid profile as an antihypertensive parameters were assessed. Isolation of bioactive compounds was carried out by chromatographic techniques and identification of the compound was done by FTIR, Mass spectrometry and NMR spectroscopy. The molecular docking study with α-amylase, α-glucosidase, dipeptidyl peptidase-IV (DPP-IV), glucokinase (GK) as diabetic markers and on 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) and Niemann-Pick C1-Like 1 (NPC1L1) was carried out.

Results

Ethyl acetate-methanol fraction of the ethanol extract showed presence of pentacyclic triterpenoids (81.5% w/w) in GC-HRMS study. Spectroscopic analysis of the isolated compound revealed presence betulin. In vitro antidiabetic activity pointed out robust inhibition of the digestive enzymes by the fractions known as bioactive fraction and betulin. Betulin at a dose of 40 mg/kg treated group showed significant improvement of diabetic conditions. The gene expression studies revealed that betulin in 40 mg/kg dose has positive effects for carbohydrate metabolism in liver, lowers the hepatic inflammation and increases insulin secretion. The plant compound demonstrated significant inhibitory potential on α-amylase, α-glucosidase, DPP-IV and GK enzymes in silico.

Conclusion

The biological study reveals that betulin could dominate the succession of diabetes in dose dependent manner. The plant and specifically Betulin exerts a significant antidiabetic and antihyperlipidemic effects that are more possibly through stimulation of insulin secretion, increase in PPAR-α level with an increase in GRIA2 mRNA expression.

Green route synthesis of ZnO nanoparticles using Senna auriculata aqueous flower extract as reducing agent and evaluation of its antimicrobial, antidiabetic and cytotoxic activity

The nanoparticles have unique and superior properties which make them applicable in almost every field of human life. Among the various methods that exist for the synthesis of nanoparticles, green synthesis is one of the best economic and eco-friendly methods compared with other conventional chemical methods. The nanoparticles synthesized by this method are also free from toxicity properties. This paper describes one such green synthesis method for zinc oxide nanoparticles (ZnO NPs) using the aqueous flower extract of Senna auriculata. The synthesized nanoparticles (SA-ZnO NPs) have been examined using UV-Vis spectrophotometer, photoluminescence spectroscopy, Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD) analysis. The antibacterial and antifungal activities of the synthesized NPs were evaluated against gram-positive bacteria (S. aureus, B. subtilis), gram-negative bacteria (E. coli, S. typhi) and fungal organisms (C. albicans, A. nigar) using disc diffusion method. Furthermore, the antidiabetic and anticancer activities of the NPs were also been examined by α-amylase inhibition assay and MTT assay, respectively. These studies ensured that the SA-ZnO NPs have significant antimicrobial, antidiabetic and anticancer activities.

A Review of Recent Studies on the Antioxidant and Anti-Infectious Properties of Senna Plants

The use of phytochemicals is gaining interest for the treatment of metabolic syndromes over the synthetic formulation of drugs. Senna is evolving as one of the important plants which have been vastly studied for its beneficial effects. Various parts of Senna species including the root, stem, leaves, and flower are found rich in numerous phytochemicals. In vitro, in vivo, and clinical experiments established that extracts from Senna plants have diverse beneficial effects by acting as a strong antioxidant and antimicrobial agent. In this review, Senna genus is comprehensively discussed in terms of its botanical characteristics, traditional use, geographic presence, and phytochemical profile. The bioactive compound richness contributes to the biological activity of Senna plant extracts. The review emphasizes on the in vivo and in vitro antioxidant and anti-infectious properties of the Senna plant. Preclinical studies confirmed the beneficial effects of the Senna plant extracts and its bioactive components in regard to the health-promoting activities. The safety, side effects, and therapeutic limitations of the Senna plant are also discussed in this review. Additional research is necessary to utilize the phenolic compounds towards its use as an alternative to pharmacological treatments and even as an ingredient in functional foods.

Digestive recovery of polyphenols, antioxidant activity, and anti-inflammatory activity of selected edible flowers from the family Fabaceae

Edible flowers are regaining popularity as therapeutic agents, due to their phytochemical composition. The present study assessed the recovery of phenolics along with the antioxidant and anti-inflammatory properties of seven edible flowers of the Fabaceae family after being subjected to simulated gastrointestinal conditions and dialysis. The total phenolic content of all the flowers decreased after the gastric phase, whereas the total flavonoid content increased. The total anthocyanin content of four flower species decreased after the intestinal phase of digestion. Cassia auriculata expressed the highest hydrogen peroxide and nitric oxide scavenging activities in the dialyzed fraction. Bauhinia racemose had the highest activity in the inhibition of heat-induced hemolysis of red blood cells after dialysis (4.43 ± 01.5%). In general, the results suggest a reduction in the phenolic contents after gastrointestinal digestion and dialysis; however, phenolics, flavonoids and anthocyanins were sufficiently available to be absorbed with the dialysis to exert antioxidant and anti-inflammatory activities. PRACTICAL APPLICATION: The presence of various phenolic compounds in edible flowers has attracted the attention of consumers as well as the food industry, due to their potential to be incorporated in functional foods and drugs. However, the availability of phenolics after digestion is an important measure to get a realistic view of the health effects exerted upon the consumption of these edible flowers. The present study provides new information on the antioxidant and anti-inflammatory potential of selected edible flowers before and after in vitro digestion. This would be more useful for nutritionists, policymakers and consumers to effectively utilize edible flowers by understanding the changes undergone by the phenolic compounds upon digestion.

Cassia auriculata and its role in infection / inflammation: A close look on future drug discovery

The herbal plants contain various active compounds which have the ability to treat several human diseases without any side effects like cancer chemotherapeutic drugs used currently. It is reported that majority of the presently used drugs are derived from natural resources like plants or their products and hence, there is an urgent need to search for novel drugs from natural resources. Accordingly, the present study was designed to exploit an ethnomedicinally important plant Cassia auriculata Linn. for the identification of its phytoconstituents responsible for various properties such as antioxidant, anti-microbial and anti-diabetic activities. Different extracts of the plant were subjected to chromatographic techniques like high-performance liquid chromatography (HPLC), gas chromatography, and mass spectrometry (GC-MS) analysis to acquire the fingerprint of the phytoconstituents present in the plant. The extracts were analyzed by Ultra Violet-Visible (UV-Visible) and Fourier-Transform Infrared Spectroscopy (FT-IR). The efficacy of the extracts was examined through different in vitro assay methods. The GC-MS study exhibited the occurrence of 48 phytoconstituents in all the tested extracts and the HPLC study revealed the presence of quercetin. Different in vitro evaluations of the plant revealed that both ethyl acetate (DPPH-IC₅₀: 340.9 μg/ml) and ethanol fractions (DPPH-IC₅₀: 205.5 μg/ml) exhibited a potent activity. Hence, using the above study, novel potent antimicrobial and anti-diabetic principles from C. auriculata can be formulated in the future towards the clinical progress of therapeutic remedies against these ailments.

Chemical composition, antioxidant, and anti-diabetic activities of ethyl acetate fraction of Stachys riederi var. japonica (Miq.) in streptozotocin-induced type 2 diabetic mice

This work analysed the chemical composition, antioxidant, and enzyme inhibitory activities of solvent extract (SJ-ME) and fractions (SJ-HF, SJ-EAF, and SJ-MF) of the Stachys riederi var. japonica (Miq.) (SJ). Furthermore, the effect of SJ-EAF in STZ induced type 2 diabetic mice was examined. Among the samples, SJ-EAF exhibited a lower IC50 concentration of 64.2 ± 0.48 μg/mL for DPPH and 82.6 ± 0.09 μg/mL for ABTS+. The SJ-EAF concentration of 2.89 ± 0.03 μg and 2.27 ± 0.98 μg was equivalent to 1 μg of acarbose mediated enzyme inhibitory effect against α-amylase and α -glucosidase, respectively. The SJ-EAF did not show cytotoxicity (<80%) to NIH3T3 nor HepG2 cells but enhanced the glucose uptake in the IR-HepG2. LC-MS/MS of SJ-EAF showed the presence of a total of 16 compounds. Among the identified compounds, rosmarinic acid, caffeic acid, oleanolic acid, and ursolic acid showed high catalytic activity of α-amylase and α-glucosidase. The treatments of SJ-EAF restored the level of blood glucose, body weight, insulin, HDL and mRNA level of IRS1, GLUT2, GLUT4 and Akt whereas it reduced the excess elevation of total cholesterol, total triglycerides, LDL, AST, ALT, ALP, BUN, and creatinine in STZ induced diabetic mice. Overall, the present study concluded that the SJ-EAF exhibited promising antidiabetic activity.

Ethnopharmacological, Phytochemical, Pharmacological, and Toxicological Review on Senna auriculata (L.) Roxb.: A Special Insight to Antidiabetic Property

Avartaki (Senna auriculata (L.) Roxb. syn. Cassia auriculata L.; Family- Fabaceae ) is a traditional medicinal plant, widely used for the treatment of various ailments in Ayurveda and Siddha system of medicine in India. Almost all the parts of the plant, such as flowers, leaves, seeds, barks, and roots have been reported for their medicinal uses. Traditionally, it has been used in the treatment of diabetes, asthma, rheumatism, dysentery, skin disease, and metabolic disorders. The principle phytochemicals in Senna auriculata (L.) Roxb. are alkaloids, anthraquinone, flavone glycosides, sugar, saponins, phenols, terpenoids, flavonoids, tannins, steroids, palmitic acid, linoleic acid, benzoic acid 2-hydroxyl methyl ester, 1-methyl butyl ester, resorcinol, α-tocopherol-β-D-mannosidase, epicatechin, ferulic acid, quercetin-3-O-rutinoside, quercetin, proanthocyanidin B1. The extracts from its different parts and their isolated compounds possess a wide range of pharmacological activities such as antidiabetic, antioxidant, anti-inflammatory, antihyperlipidemic, hepatoprotective, nephroprotective, cardioprotective, anti-atherosclerotic, anticancer, antimutagenic, antimicrobial, antiulcer, antipyretic, anthelmintic, immunomodulatory, antifertility, anti-venom, and anti-melanogenesis. The toxicological findings from preclinical studies ensured the safety of the plant, but comprehensive clinical studies are required for the safety and efficacy of the plant in humans. The current review article aimed to provide up-to-date information about Senna auriculata (L.) Roxb. covering its ethnomedicinal, phytochemical, pharmacological, and toxicological aspects with special emphasis on its clinical implications in diabetes.

Ameliorative potential of Operculina turpethum against streptozotocin-induced diabetes in rats: biochemical and histopathological studies

The study aimed to investigate the acute toxicity, antidiabetic potential (in-vitro and in-vivo) of the Operculina turpethum (L.) Silva Manso at fraction level. The plant was fractionated into different fractions, i.e., flavonoid fraction (OTFF), tannin fraction (OTTF), saponin fraction (OTSF). In-vitro alpha-amylase inhibition assay revealed that OTFF was found to be more potent than standard Acarbose. The plant fractions were evaluated by MTT assay at different concentrations ranging from 100 to 1000 µg/ml. All the fractions were further evaluated for their safety profile, and the biochemical, hematology and histopathology result exhibits that the OTFF fraction produces mild toxicity at organ level at a concentration of 2000 mg/kg in albino mice. The in-vivo antidiabetic study was carried out on Sprague-Dawley rats using high-fat diet (HFD) feeding streptozotocin (STZ) diabetic model, and the biochemical, histopathology research findings represent that OTFF at a concentration of 500 mg/kg, p.o. was found to be highly significant among all the fractions and found to be more potent than the standard Acarbose. LC-MS characterization of the bioactive fraction OTFF showed the presence of rutin with m/z 610.52 in 50.50% and Apigenin 7-O-6'' acetyl-glucoside with m/z 475.42 in 24.10%; from molecular docking study, it is predicted that the fraction primarily acts as an alpha-amylase inhibitor and PPAR gamma agonist. In conclusion, the plant's OTFF fraction acts as a potential therapeutic agent for Type II diabetes mellitus.

Protective effects of calorie restriction on insulin resistance and islet function in STZ-induced type 2 diabetes rats

Background

Caloric restriction (CR) has become increasingly attractive in the treatment of type 2 diabetes mellitus (T2DM) because of the increasingly common high-calorie diet and sedentary lifestyle. This study aimed to evaluate the role of CR in T2DM treatment and further explore its potential molecular mechanisms.

Methods

Sixty male Sprague–Dawley rats were used in this study. The diabetes model was induced by 8 weeks of high-fat diet (HFD) followed by a single dose of streptozotocin injection (30 mg/kg). Subsequently, the diabetic rats were fed HFD at 28 g/day (diabetic control) or 20 g/day (30% CR regimen) for 20 weeks. Meanwhile, normal rats fed a free standard chow diet served as the vehicle control. Body mass, plasma glucose levels, and lipid profiles were monitored. After diabetes-related functional tests were performed, the rats were sacrificed at 10 and 20 weeks, and glucose uptake in fresh muscle was determined. In addition, western blotting and immunofluorescence were used to detect alterations in AKT/AS160/GLUT4 signaling.

Results

We found that 30% CR significantly attenuated hyperglycemia and dyslipidemia, leading to alleviation of glucolipotoxicity and thus protection of islet function. Insulin resistance was also markedly ameliorated, as indicated by notably improved insulin tolerance and homeostatic model assessment for insulin resistance (HOMA-IR). However, the improvement in glucose uptake in skeletal muscle was not significant. The upregulation of AKT/AS160/GLUT4 signaling in muscle induced by 30% CR also attenuated gradually over time. Interestingly, the consecutive decrease in AKT/AS160/GLUT4 signaling in white adipose tissue was significantly reversed by 30% CR.

Conclusion

CR (30%) could protect islet function from hyperglycemia and dyslipidemia, and improve insulin resistance. The mechanism by which these effects occurred is likely related to the upregulation of AKT/AS160/GLUT4 signaling.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12986-021-00575-y.

Evaluation of antidiabetic activity of dietary phenolic compound chlorogenic acid in streptozotocin induced diabetic rats: Molecular docking, molecular dynamics, in silico toxicity, in vitro and in vivo studies

BACKGROUND

Chlorogenic acid is amongst the well-known polyphenolic compounds being used in human food and beverages. Its presence has been reported in tea leaves, roasted green beans, coffee, cocoa, berry fruits, apples, citrus fruits, and pears.

OBJECTIVE

The present study aims to elucidate the effectiveness of chlorogenic acid on in silico and in vitro inhibition of glucose metabolising enzymes (α-amylase and α-glucosidase) and on blood-based markers associated with diabetic complications in vivo.

METHODS

Docking and molecular dynamics studies were performed using GLIDE (Schrodinger, LLC, NY, 2019-2) and Maestro-Desmond Interoperability Tools, version 4.1 (Schrödinger, NY, 2015), respectively. α-Amylase and α-glucosidase inhibitory activities of chlorogenic acid were measured in vitro. Diabetes was induced in adult Wistar rats by injecting streptozotocin (50 mg/kg). Biochemical assays were performed using standard kits.

RESULT

The in silico studies for α-amylase and α-glucosidase with chlorogenic acid suggested that the ligand was stable and strongly bound with the above-mentioned proteins. During in vitro studies, chlorogenic acid inhibited both the enzymes in a dose-dependent manner (5-30 μg/mL). In addition, chlorogenic acid treatment for 28 days significantly suppressed the increase in blood glucose, total cholesterol, triglyceride, glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, γ-glutamyl transferase, alkaline phosphatase, total bilirubin, creatinine, urea, uric acid, and feed intake levels in diabetic rats. Chlorogenic acid also caused significant improvement in body weight, serum HDL-cholesterol, total protein, and albumin levels leading to betterment in atherogenic indices related to diabetes-associated cardiovascular risks.

CONCLUSION

The findings indicated that chlorogenic acid inhibited α-amylase and α-glucosidase and significantly decreased diabetes associated hyperglycemia, hyperlipidemia, and hepatorenal damage, making it a possible functional food ingredient and drug candidate for the management of diabetes and related complications.

Nutraceutical potential of dietary phytochemicals in edible flowers-A review

Edible flowers have been in traditional cuisine and phytotherapy for centuries. Recently, the consumption of edible flowers has increased significantly as the phytochemicals in them are known to have numerous health benefits. Information on nutraceutical potentials and health benefits of the phytochemicals available in different varieties of edible flowers and their uses are discussed. It is found that the major groups of dietary phytochemicals in edible flowers include flavonoids, phenolic acids, and anthocyanins and they are capable of exerting antioxidant, anti-inflammatory, anti-diabetic, anticancer, cardioprotective, hepatoprotective gastroprotective, and genoprotective effects. PRACTICAL APPLICATIONS: Edible flowers are good sources of phytochemicals and possessing antioxidant, anti-inflammatory properties, anticancer, anti-diabetic, and cardio-protective properties. However, many edible flowers remain unexplored and underutilized. This review gives eye openings that more in-depth investigations need to be conducted on different edible flowers and they need to be incorporated into commercialized foods and drugs or need to be used for novel nutraceutical development to deliver the potential health benefits to consumers.

Ameliorative Efficacy of the Cassia auriculata Root Against High-Fat-Diet + STZ-Induced Type-2 Diabetes in C57BL/6 Mice

Diabetes mellitus is a major metabolic disorder worldwide. Several herbs are being tested for the management of diabetes. Cassia auriculata is one of those herbs known for its nutritional value and health benefits. However, limited scientific evidence has been shown on the elucidation of its root bioactives as well as biological activity. This study attempted to identify and characterize phenolic compounds from the potent root extract and to evaluate its antioxidant as well as antidiabetic properties in both in vitro and in vivo models. The results revealed that the total polyphenol and flavonoid contents were highest in the methanolic extract. The methanolic extract of the C. auriculata root showed the highest antioxidant and antidiabetic activities in vitro than other extracts. These biological activities may be because the extract is rich in coumaric acid and -OH groups as revealed by high-performance liquid chromatography and Fourier-transform infrared spectroscopy analyses, respectively. Further, the antidiabetic activity of the methanolic extract was studied in a diet-induced type-2 diabetes mellitus (T2DM) C57BL/6 mouse model. A significant increase in fasting blood glucose and decreased plasma insulin levels in T2DM mice confirmed the development of the diabetic condition. In addition, the T2DM mice showed oxidative stress in the plasma as well as muscle tissue and significant alterations in the plasma biochemistry, viz., lipid profile, liver, and renal function tests. However, the administration of the ethanolic extract of the C. auriculata root (150 mg/kg body weight) to T2DM mice normalized the condition comparable to that of control mice. Thus, the extract can be used as a potent antioxidant and antidiabetic agent in pharmaceutical companies.

Hypoglycemic, antidyslipidemic and antioxydant effects of Vitellaria paradoxa barks extract on high-fat diet and streptozotocin-induced type 2 diabetes rats

Backgroud

Vitellaria paradoxa is a plant belonging to the Sapotaceae family and used in traditional medicine in the treatment of diabetes mellitus. The aim of this work was to evaluate the hypoglycemic, antidyslipidemic and antioxidant effects of V. paradoxa on type 2 diabetic rats.

Methods

To induce type 2 diabetes mellitus (T2DM), animals were fed a high-fat diet for 4 weeks followed by an intraperitoneal injection of 35 mg/kg of streptozotocin. Diabetic rats were divided into groups and treated for 28 days with V. paradoxa extract (AEVP) at doses of 125, 250 and 500 mg/kg. Body weight, urine volume, food and water consumption were assessed at the start and end of treatment. The glucose tolerance test was performed on the last day of treatment. Blood samples were taken for the assay of biochemical parameters, organs (kidneys and liver) for markers of oxidative stress and pancreas for histological sections.

Results

AEVP (250 and 500 mg/kg) improved the drop in body weight, polyphagia, polydipsia and polyuria in diabetic rats. AEVP significantly reduced the concentrations of glucose, total cholesterol, triacylglycerol, urea, creatinine, activities of transaminases, and increased the levels of high density lipoprotein cholesterol and serum insulin. AEVP resulted in a decrease in malondialdehyde levels and an increase in catalase and superoxide dismutase activities. An increase in the size and number of islets in the pancreas has also been observed after administration of the extract.

Conclusion

AEVP has antidiabetic, antidyslipidemic and antioxidant properties, thus confirming its traditional use for the treatment of diabetes. These effects could be due to the presence of phytoconstituents, phenols and flavonoids presents in the plant extract.

Cichorium intybus attenuates Streptozotocin-induced pancreatic β-cell damage by inhibiting NF-κB activation and oxidative stress

The aqueous extract of Cichorium intybus (CIE) leaves have shown the properties of protecting against pancreatic β-cell damage by streptozotocin (STZ), but the molecular mechanisms of its protection are not completely elucidated yet. Our current study focuses on elucidating the mechanisms of these preventive effects of CIE in MIN6 cells and an in-vivo model of Wistar rats. CIE offers protection against STZ in MIN6 cells by reducing the pro-oxidants and increasing the activity of the antioxidant enzymes. In vitro results also indicated that CIE inhibited cytotoxicity, reduced Reactive oxygen species (ROS), maintained glucose-stimulated insulin secretion and reduced NF-κB p65 translocation into the nucleus. The group administered with a 250 mg/kg dose of CIE in vivo has shown an ability to maintain blood glucose level and also to preserve the number and morphology of pancreatic islets when compared to the diabetic group treated with STZ. Probably, active compounds like quercetin, rutin, and catechin present in CIE, preserve the integrity of pancreatic islets thereby protecting β-cells from the adverse effects of STZ.

Therapeutic Effects of 5,7-Dihydroxy-6-Oxoheptadecanoic Acid on Dysglycemia, Dyslipidemia, and Other Complications in Diabetic Rats

The current study aimed to investigate the therapeutic effects of 5,7-dihydroxy-6-oxoheptadecanoic acid (DHA) from Tiliacora triandra on rat models of type 2 diabetes mellitus (T2DM). T2DM was induced with a combination of high-fat diet/streptozotocin (HFD/STZ), and diabetic rats were treated with DHA (25 mg/kg) for 30 days. The body weight, fasting blood glucose (FBG), serum, and liver biochemical parameters, as well as histological evaluations of the liver and pancreas, were evaluated. Diabetic rats displayed a significant increase in FBG, serum lipid profiles (triglycerides, total cholesterol, and low-density lipoprotein cholesterol), liver function enzymes (aspartate transaminase, alkaline phosphatase, and alanine transaminase), creatinine, liver malondialdehyde (MDA), and myeloperoxidase (MPO) contents. Furthermore, insulin level and liver antioxidant enzyme activities (catalase [CAT], superoxide dismutase [SOD], and glutathione peroxidase [GSH-Px]) were significantly reduced in the diabetic rats. Whereas, treatment with DHA significantly reduced FBG, serum lipids, liver function enzymes, serum creatinine, liver MDA, and MPO contents. In addition, treatment with DHA significantly increased serum insulin level and liver SOD, CAT, and GSH-Px activities. In addition, DHA alleviated histopathological changes in the pancreas and liver caused by T2DM. These results portray the antidiabetic and antioxidative properties of DHA and can be considered as a potential treatment for T2DM.

Genome-wide identification of lncRNAs during hickory (Carya cathayensis) flowering

Non-coding RNAs with lengths greater than 200 bp are known as long non-coding RNAs (lncRNAs), and these RNAs play important role in gene regulation and plant development. However, to date, little is known regarding the role played by lncRNAs during flowering in hickory (Carya cathayensis). Here, we performed whole transcriptome RNA-sequencing of samples from hickory female and male floral buds, in which three samples (H0311PF, H0318PF, and H0402PF) represent pre-flowering, flowering, and post-flowering, respectively, while eight male samples collected from May 8th to June 13th as this time course are the key stage for male floral bud differentiation. We identified 2163 lncRNAs in hickory during flowering, containing 213 intronic, 1488 intergenic, and 462 antisense lncRNAs. We noticed that 510 and 648 lncRNAs were differentially expressed corresponding to female and male floral buds, respectively. And some of the lncRNAs were in a tightly tissue-specific or stage-specific manner. To further understand the roles of the lncRNAs, we predicted the function of the lncRNAs in cis- and trans-acting modes. The results showed that 924 lncRNAs were cis-correlated with 1536 protein-coding genes, while 1207 lncRNAs co-expressed (trans-acting) with 7432 protein-coding genes (R > 0.95 or R < - 0.95). These lncRNAs were all enriched in flower development-associated biological processes, i.e., circadian rhythm, vernalization response, response to gibberellin, inflorescence development, floral organ development, etc. To further understand the relationships between lncRNAs and floral-core genes, we build a co-expressing lncRNA-mRNA flowering network. We classified these floral genes into different pathway (photoperiod, vernalization, gibberellin, autonomous, and sucrose pathway) according to their particular functions. We found a set of lncRNAs that preferentially expressed in these pathways. The network showed that some lncRNAs (i.e., XLOC_038669, XLOC_017938) functioned in a particular flowering time pathway, while others (i.e., XLOC_011251, XLOC_04110) were involved in multiple pathway. Furthermore, some lncRNAs (i.e., XLOC_038669, XLOC_009597, and XLOC_049539) played roles in single or multiple pathways via interaction with each other. This study provides a genome-wide survey of hickory flower-related lncRNAs and will contribute to further understanding of the molecular mechanism underpinning flowering in hickory.

Synergistic effect of novel chitosan combined metformin drug on streptozotocin-induced diabetes mellitus rat

Metformin is widely used as a frontline medicine of type-II diabetes. Frequent overdose side-effects and their consequent adversative need to be reduced. The novel source of marine hydrozoa, Thyroscyphus ramosus derived chitosan combined metformin drug was administrated to evaluate the antidiabetic potential on a high-fat diet (HFD) with streptozotocin (STZ) induced diabetic rats. The primary analysis of In vitro antioxidant activity was tested for various solvent dissolved chitosan. Based on their IC₅₀ dose values, CsnAA was chosen for further experiments. The chitosan was combined with metformin by sonication and confirmed through XRD, FTIR and SEM analysis. The enhanced activity was observed in 100 mg/kg metformin combined with CSN500mg/kg. The level of serum bilirubin, total protein, SGH, liver glycogen, Glucose-6-phosphatase and fructose-1,6- phosphatase values were significantly similar to metformin 300 mg/kg treated group. With this beneficiary, the novel chitosan was recommended to administrate with metformin to improve the drug efficacy and reduction of overdose lethal effects.