Antihyperglycemic effect of Ginkgo biloba extract in streptozotocin-induced diabetes in rats

Vasorelaxant effects of biochemical constituents of various medicinal plants and their benefits in diabetes

Endothelial function plays a pivotal role in cardiovascular health, and dysfunction in this context diminishes vasorelaxation concomitant with endothelial activity. The nitric oxide-cyclic guanosine monophosphate pathway, prostacyclin-cyclic adenosine monophosphate pathway, inhibition of phosphodiesterase, and the opening of potassium channels, coupled with the reduction of calcium levels in the cell, constitute critical mechanisms governing vasorelaxation. Cardiovascular disease stands as a significant contributor to morbidity and mortality among individuals with diabetes, with adults afflicted by diabetes exhibiting a heightened cardiovascular risk compared to their non-diabetic counterparts. A plethora of medicinal plants, characterized by potent pharmacological effects and minimal side effects, holds promise in addressing these concerns. In this review, we delineate various medicinal plants and their respective biochemical constituents, showcasing concurrent vasorelaxant and anti-diabetic activities.

Harmine alleviated STZ-induced rat diabetic nephropathy: A potential role via regulating AMPK/Nrf2 pathway and deactivating ataxia-telangiectasia mutated (ATM) signaling

Diabetic nephropathy (DN) is a serious kidney disorder driven by diabetes and affects people all over the world. One of the mechanisms promoting NF-κB-induced renal inflammation and injury has been theorized to be ATM signaling. On the other hand, AMPK, which can be activated by the naturally occurring alkaloid harmine (HAR), has been proposed to stop that action. As a result, the goal of this study was to evaluate the therapeutic effectiveness of HAR against streptozotocin (STZ)-induced DN in rats through AMPK-mediated inactivation of ATM pathways. Twenty male Wistar rats were grouped into 4 groups, as follow: CONT, DN, HAR (10 mg/kg), DN + HAR, where HAR was daily administered I.P. once for 2 weeks. The renal AMPK and PGC-1α expressions, as well as Sirt1 levels, were assessed. To ascertain the oxidative reactions, renal Nrf2 expression, HO-1, MDA, and TAC concentrations were measured. As parts of ATM pathways, ATM and p53 expressions, in addition to GSK-3β levels were determined. Renal expression of NEMO, TNF-α, and IL-6 levels were also estimated. Moreover, histopathological and immunohistochemical detection of Bcl-2, Bax, and caspase 3 were reported. Results indicated that HAR intake notably alleviated STZ-induced kidney damage by triggering AMPK and Sirt1, which in turn boosted PGC-1α, improved NRf2/HO-1 axis, and lowered ROS production. As a consequence, HAR blocked the ATM-triggered renal inflammation and minimized caspase-3 expression by repressing the Bax/Bcl2 ratio. Because of its ability to activate AMPK/Nrf2 axis, HAR may represent an emerging avenue for future DN therapy by blocking ATM pathways.

Morin ameliorates myocardial injury in diabetic rats via modulation of inflammatory pathways

BACKGROUND

High blood glucose levels in diabetes lead to vascular inflammation which accelerates atherosclerosis. Herein, Morin was orally administered in male Wistar rats, at the dose of 40 mg/kg for 28 days, and on the 27th and 28th day, ISO was administered to designate groups at the dose of 85 mg/kg s.c., to induce myocardial infarction.

RESULTS

Free radical generation, including ROS, in diabetes following ISO administration, leads to the activation of both intrinsic and extrinsic pathways of apoptosis. Morin significantly (p ≤ 0.05) reduced oxidative stress (GSH, MDA, SOD), cardiac injury markers (CK-MB, LDH), inflammation (TNF, IL-6), and apoptosis (Bax, BCl2, Caspase-3). In addition, it also reduced insulin and blood glucose levels. Akt/eNOS, Nrf2/HO-1, MAPK signaling pathways, and Insulin signal transduction pathways were positively modulated by morin pre-treatment.

CONCLUSIONS

Morin attenuated oxidative stress and inflammation and also modified the activity of various molecular pathways to mitigate cardiomyocyte damage during ISO-induced MI in diabetic rats.

Nrf2 Pathway and Oxidative Stress as a Common Target for Treatment of Diabetes and Its Comorbidities

Diabetes is a chronic disease that induces many comorbidities, including cardiovascular disease, nephropathy, and liver damage. Many mechanisms have been suggested as to how diabetes leads to these comorbidities, of which increased oxidative stress in diabetic patients has been strongly implicated. Limited knowledge of antioxidative antidiabetic drugs and substances that can address diabetic comorbidities through the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway calls for detailed investigation. This review will describe how diabetes increases oxidative stress, the general impact of that oxidative stress, and how oxidative stress primarily contributes to diabetic comorbidities. It will also address how treatments for diabetes, especially focusing on their effects on the Nrf2 antioxidative pathway, have been shown to similarly affect the Nrf2 pathway of the heart, kidney, and liver systems. This review demonstrates that the Nrf2 pathway is a common pathogenic component of diabetes and its associated comorbidities, potentially identifying this pathway as a target to guide future treatments.

Alleviate oxidative stress in diabetic retinopathy: antioxidant therapeutic strategies

OBJECTIVES

This review outlines the function of oxidative stress in DR and discusses therapeutic strategies to treat DR with antioxidants.

METHODS

Published papers on oxidative stress in DR and therapeutic strategies to treat DR with antioxidants were collected and reviewed via database searching on PubMed.

RESULTS

The abnormal development of DR is a complicated process. The pathogenesis of DR has been reported to involve oxidative stress, despite the fact that the mechanisms underlying this are still not fully understood. Excessive reactive oxygen species (ROS) accumulation can damage retina, eventually leading to DR. Increasing evidence have demonstrated that antioxidant therapy can alleviate the degeneration of retinal capillaries in DR.

CONCLUSION

Oxidative stress can play an important contributor in the pathogenesis of DR. Furthermore, animal experiments have shown that antioxidants are a beneficial therapy for treating DR, but more clinical trial data is needed.

Effect of Prunetin on Streptozotocin-Induced Diabetic Nephropathy in Rats - a Biochemical and Molecular Approach

In the modern era, chronic kidney failure due to diabetes has spread across the globe. Prunetin (PRU), a component of herbal medicines, has a broad variety of pharmacological activities; these may help to slow the onset of diabetic kidney disease. The anti-nephropathic effects of PRU have not yet been reported. The present study explored the potential nephroprotective actions of PRU in diabetic rats. For 28 days, nephropathic rats were given oral doses of PRU (20, 40, and 80 mg/kg). Body weight, blood urea, creatinine, total protein, lipid profile, liver marker enzymes, carbohydrate metabolic enzymes, C-reactive protein, antioxidants, lipid peroxidative indicators, and the expression of insulin receptor substrate 1 (IRS-1) and glucose transporter 2 (GLUT-2) mRNA genes were all examined. Histological examinations of the kidneys, liver, and pancreas were also performed. The oral treatment of PRU drastically lowered the blood glucose, HbA1c, blood urea, creatinine, serum glutamic-oxaloacetic transaminase, serum glutamic pyruvic transaminase, alkaline phosphatase, lipid profile, and hexokinase. Meanwhile, the levels of fructose 1,6-bisphosphatase, glucose-6-phosphatase, and phosphoenol pyruvate carboxykinase were all elevated, but glucose-6-phosphate dehydrogenase dropped significantly. Inflammatory marker antioxidants and lipid peroxidative markers were also less persistent due to this administration. PRU upregulated the IRS-1 and GLUT-2 gene expression in the nephropathic group. The possible renoprotective properties of PRU were validated by histopathology of the liver, kidney, and pancreatic tissues. It is therefore proposed that PRU (80 mg/kg) has considerable renoprotective benefits in diabetic nephropathy in rats.

Antioxidant Effect of the Ethyl Acetate Extract of Potentilla indica on Kidney Mitochondria of Streptozotocin-Induced Diabetic Rats

Diabetes mellitus (DM) is a metabolic disorder characterized by persistent hyperglycemia. This state may lead to an increase in oxidative stress, which contributes to the development of diabetes complications, including diabetic kidney disease. Potentilla indica is a traditional medicinal herb in Asia, employed in the treatment of several diseases, including DM. In this study, we investigated the antioxidant effect of the ethyl acetate extract of Potentilla indica both in vitro and on kidneys of streptozotocin-induced diabetic male rats. Firstly, phytochemicals were identified via UPLC-MS/MS, and their in vitro antioxidant capabilities were evaluated. Subsequently, male Wistar rats were assigned into four groups: normoglycemic control, diabetic control, normoglycemic treated with the extract, and diabetic treated with the extract. At the end of the treatment, fasting blood glucose (FBG) levels, creatinine, blood urea nitrogen (BUN), and uric acid were estimated. Furthermore, the kidneys were removed and utilized for the determination of mitochondrial reactive oxygen species (ROS) production, mitochondrial respiratory chain complex activities, mitochondrial lipid peroxidation, glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT) activities. The in vitro findings showed that the major phytochemicals present in the extract were phenolic compounds, which exhibited a potent antioxidant activity. Moreover, the administration of the P. indica extract reduced creatinine and BUN levels, ROS production, and lipid peroxidation and improved mitochondrial respiratory chain complex activity and GSH-Px, SODk, and CAT activities when compared to the diabetic control group. In conclusion, our data suggest that the ethyl acetate extract of Potentilla indica possesses renoprotective effects by reducing oxidative stress on the kidneys of streptozotocin-induced diabetic male rats.

Green Coffee Bean Extract Potentially Ameliorates Liver Injury due to HFD/STZ-Induced Diabetes in Rats

The goal of the current study was to examine the therapeutic potential of green coffee bean extract (GCBE) in the treatment of diabetic hepatic damage induced by high-fat diet (HFD) and streptozotocin (STZ) administration. The novelty of this study lies in constructing a newly stabilized in vivo obese diabetic animal model in rats using HFD/STZ for investigating the dose-dependent effect of two commonly used doses of GCBE in hepatoprotection against oxidative stress-induced hepatic damage by measuring many parameters that have not been carried out previously in other studies. GCBE that was used in this study was a hot water extract of green coffee beans with a concentration of 0.1 g ml−1. Male albino rats were given a single dose of STZ (35 mg kg−1), and HFD to induce diabetes mellitus (DM). For 28 days, two separate doses of GCBE 50 mg kg−1 and 100 mg kg−1 were administered orally to diabetic animals. Leptin, liver enzymes, oxidative stress parameters, inflammatory parameters, fasting plasma glucose (FPG), fasting plasma insulin (FPI), and lipid profile levels were examined. Real-time PCR and ELISA were used to quantitatively detect the mRNAs of the genes involved in the insulin signaling pathway, the genes involved in glucose metabolism, and the amounts of proteins. The levels of FPG, lipid profile, liver enzymes, inflammatory markers, and leptin in the HFD/STZ diabetic group revealed a considerable spike, while they considerably decreased after GCBE treatment in a dose-dependent manner. After GCBE treatment, the diabetic group showed a significant rise in the antioxidant markers glutathione, superoxide dismutase, and catalase, as well as a decrease in malondialdehyde and nitric oxide levels. The liver changes caused by HFD/STZ were entirely reversed by GCBE, and most intriguingly, in a dose-dependent manner. We concluded that GCBE can repair the hepatic oxidative damage caused by HFD and STZ by reversing all the previously measured parameters and improving the insulin signaling pathways. GCBE demonstrated strong antifree radical activity and significantly protected cells from oxidative damage caused by HFD/STZ.

Nutraceuticals as Supportive Therapeutic Agents in Diabetes and Pancreatic Ductal Adenocarcinoma: A Systematic Review

The correlation between pancreatic ductal adenocarcinoma (PDAC) and diabetes-related mechanisms support the hypothesis that early therapeutic strategies targeting diabetes can contribute to PDAC risk reduction and treatment improvement. A systematic review was conducted, using PubMed, Embase and Cochrane Library databases, to evaluate the current evidence from clinical studies qualitatively examining the efficacy of four natural products: Curcumin-Curcuma longa L.; Thymoquinone-Nigella sativa L.; Genistein-Glycine max L.; Ginkgo biloba L.; and a low-carbohydrate ketogenic diet in type 2 diabetes (T2D) and PDAC treatment. A total of 28 clinical studies were included, showing strong evidence of inter-study heterogeneity. Used as a monotherapy or in combination with chemo-radiotherapy, the studied substances did not significantly improve the treatment response of PDAC patients. However, pronounced therapeutic efficacy was confirmed in T2D. The natural products and low-carbohydrate ketogenic diet, combined with the standard drugs, have the potential to improve T2D treatment and thus potentially reduce the risk of cancer development and improve multiple biological parameters in PDAC patients.

Tenovin-1 Ameliorates Renal Fibrosis in High-Fat-Diet-Induced Diabetic Nephropathy via Antioxidant and Anti-Inflammatory Pathways

High-fat diet (HFD)-induced obesity has been involved in the development of diabetic nephropathy (DN). Tenovin-1, a potent selective SIRT1/2 inhibitor, regulates various target proteins. The present study evaluated the protective effect of Tenovin-1 against renal fibrosis in HFD-induced Zucker diabetic fatty (ZDF) rats. Rats were fed a normal chow diet or HFD. Tenovin-1 (45 mg/kg) administered to HFD-fed rats decreased inflammatory cytokine expression in the serum of the rats. The antioxidant status and oxidative damage to lipids or DNA were significantly restored by Tenovin-1. Additionally, Tenovin-1 reduced the levels of blood urea nitrogen (BUN), serum creatinine (sCr), microalbumin, and urinary protein-based biomarkers in the urine of HFD-fed rats. The abnormal architecture of the kidney and pancreas was restored by Tenovin-1 administration. Tenovin-1 also reduced apoptosis in the kidneys of the HFD-fed rats and HG-treated NRK-52E cells. It significantly lowered the levels of ECM proteins in the kidneys of HFD-fed rats and HG-treated NRK-52E cells. Additionally, Tenovin-1 markedly reduced claudin-1, SIRT1, and SIRT2, but increased SIRT3 and SIRT4 in HFD-fed rats and NRK-52E cells treated with HG. Furthermore, Tenovin-1 altered epidermal growth factor receptor (EGFR), platelet-derived growth factor receptor-β (PDGFR-β), and signal transducer and activator of transcription 3 (STAT3) levels in the kidneys of HFD-fed rats. Conclusively, this study shows that Tenovin-1 can be a potential candidate drug for the treatment of HFD-induced renal fibrosis, in vivo and in vitro models.

Antioxidant Capacities and Enzymatic Inhibitory Effects of Different Solvent Fractions and Major Flavones from Celery Seeds Produced in Different Geographic Areas in China

To extend the application of celery (Apium graveolens L.) seeds, the antioxidant and enzymatic inhibitory activities of different fractions and their main flavones were investigated. The n-butanol fractions possessed the highest total phenolic content (TPC) and total flavonoid content (TFC) values. The n-butanol fractions from Northeast China samples exhibited the strongest free radical scavenging (DPPH IC₅₀ = 20.27 μg/mL, ABTS IC₅₀ = 15.11 μg/mL) and ferric reducing antioxidant power (FRAP 547.93 mg trolox (TE)/g) capacity, while those collected from Hubei China showed the optimal cupric reducing antioxidant capacity (CUPRAC) values (465.78 mg TE/g). In addition, the dichloromethane fractions from Jiangsu samples displayed a maximum Fe²⁺ chelating capacity (20.81 mg ethylene diamine tetraacetic acid (EDTA)/g). Enzyme level experiments indicated polyphenolic compounds might be the main hypoglycemic active components. Subsequently, the enzyme inhibitory activity of nine main flavones was evaluated. Chrysoeriol-7-O-glucoside showed better α-glucosidase inhibitory activity than others. However, apigenin showed the best inhibitory effect on α-amylases, while the presence of glycosides would reduce its inhibitory effect. This study is the first scientific report on the enzymatic inhibitory activity, molecular docking, and antioxidant capacity of celery seed constituents, providing a basis for treating or preventing oxidative stress-related diseases and hyperglycemia.

Protective Effects of the Bilobalide on Retinal Oxidative Stress and Inflammation in Streptozotocin-Induced Diabetic Rats

Diabetic retinopathy (DR) is a diabetes mellitus (DM) complication that causes visual acuity impairment and loss of sight in the working population, mainly in developed countries. According to the WHO, DR accounts for 5% of the world's 37 million blind people. The prevalence of diabetic retinopathy was highest in Africa, followed by North America and the Caribbean and South and Central America. Hyperglycemia can generate excessive ROS that activates multiple pathways, which can damage the cells. Oxidative stress and inflammatory process are intricate in the DR pathological mechanism. Bilobalide is the main bioactive compound isolated from the Ginkgo biloba, a plant utilized in folklore medicine. Bilobalide, a sesquiterpene trilactone, exhibits excellent antioxidant activity. But the molecular mechanisms associated with such effects, especially the antioxidant-related mechanism, have not been documented. Hence, this investigation explored whether bilobalide may attenuate DR in streptozotocin (STZ)-prompted diabetic rats. The effects of bilobalide on parameters of antioxidant content, oxidative stress, and inflammatory factors in the retinal tissues were evaluated by ELISA, RT-PCR, and immunohistochemistry methods. Bilobalide improved caloric management by reducing food consumption and increasing body weight. Furthermore, the administration of bilobalide decreases the blood glucose level and glycosylated (HbA1c) hemoglobin. The anti-retinopathy activity of bilobalide was established by the increase in the total retina thickness (TRT), inner nuclear layer (INL), and outer nuclear layer (ONL) in diabetic rats. Additionally, the serum level of MDA was decreased. In contrast, the antioxidant enzyme (SOD and CAT) levels were increased with TAC plus lower Keap1 and higher Nrf2 expression in the retina when associated with the DM rats. Moreover, bilobalide increased the nuclear factor erythroid 2-related factor 2 (Nrf2) and Heme oxygenase-1 (HO-1) expression level and inflammatory mediators (NF-κβ p65, TNF-α, IL-1β, and VEGF), thus inhibiting oxidative stress. Bilobalide can be effective against DR, and the possible mechanism may be relatively elucidated by decreasing oxidative stress and anti-inflammatory activities. But the further investigation should be directed to expose the precise mechanism.

Molineria recurvata Ameliorates Streptozotocin-Induced Diabetic Nephropathy through Antioxidant and Anti-Inflammatory Pathways

Molineria recurvata (MR) has been traditionally used to manage diabetes mellitus in India. However, the molecular mechanism of MR on the diabetic-induced nephropathy has not been clearly investigated. Thus, this study investigates the protective effects of the MR extract on nephropathy in streptozotocin (STZ)-induced diabetic rats. Diabetes was instigated by a single intraperitoneal injection of STZ (45 mg/kg) in male Sprague-Dawley rats. Once the diabetes was successfully induced, the MR extract (200 mg/kg/day) or metformin (200 mg/kg/day) was orally administered for 14 days. Renal function, morphology changes and levels of inflammatory cytokines were measured. Blood glucose concentrations were considerably reduced in STZ-induced diabetic rats following treatment with the MR extract. The administration of the MR extract substantially restored the abnormal quantity of the oxidative DNA damage marker 8-hydroxy-2′-deoxy-guanosine (8-OHdG), malondialdehyde, glutathione, oxidized glutathione, superoxide dismutase, catalase, interleukin (IL)-1β, IL-6, IL-10, and transforming growth factor-β (TGF-β). The urinary excretion of kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), selenium binding protein 1 (SBP1), and pyruvate kinase M2 (PKM2) was significantly reduced in diabetes rats after administration of the MR extracts. In the kidneys of STZ-induced diabetic rats, the MR extracts markedly downregulated the expression of fibronectin, collagen-1, and α-smooth muscle actin (α-SMA). In particular, the MR extracts markedly increased the level of SIRT1 and SIRT3 and reduced claudin-1 in the kidney. These results suggest that the MR extracts exhibits therapeutic activity in contrast to renal injury in STZ-induced diabetic rats through repressing inflammation and oxidative stress.

Traversing through half a century research timeline on Ginkgo biloba, in transforming a botanical rarity into an active functional food ingredient

Neurodegenerative diseases and various other chronic ailments have gradually transformed into public-health issues. Neurodegenerative disorders are a range of progressive neural abnormalities characterized by cellular dysfunctions, neuronal structure, and function loss. Among many chronic disorders, oxidative stress, inflammation, mitochondrial dysregulation, and cellular alterations in the human body are considered the most prevalent diagnostic symptoms. They have a profound impact on patients' health and wellbeing. The disease's poor curability, high healthcare costs, and lethality are the principal reasons for approaching and exploring the conventional treatment's phytotherapeutic alternatives. Ginkgo biloba (Maidenhair tree) is a well-known and widely used herbal plant in the Ginkgoaceae family. Its phytochemical constituents, Flavonoids, and terpenes, have been identified as the primary ingredients of Ginkgo biloba leaf extracts. It has been widely used due to its therapeutic properties, including its neuroprotective, anti-dementia, antioxidant, anti-inflammatory, vasoactive, anti-psychotic, anti-neoplastic, and anti-platelet activity. In recent decades, plenty of Ginkgo-derived substances has been researched and elucidated to have significant therapeutic effects in numerous disease models. This review aims to provide a thorough understanding of the botanical basis for Ginkgo biloba, its usage as herbal medicine, and its pivotal role in functional foods. Additionally, the clinical significance of Ginkgo biloba, as observed in various research works and clinical investigations, is also emphasized, facilitating a better understanding of their molecular basis and application in many chronic diseases.

Actinidia deliciosa Mitigates Oxidative Stress and Changes in Pancreatic α-, β-, and δ-Cells and Immunohistochemical and Histological Architecture in Diabetic Rats

The present study evaluated the antioxidant capacity and antidiabetic effect of Actinidia deliciosa in diabetic rats. Rats were grouped as follows: control, Actinidia deliciosa aqueous extract (ADAE, 1 g/kg, daily and orally), streptozotocin (STZ, 50 mg/kg BW, single intraperitoneal dose), and STZ plus ADAE, respectively. Twenty-eight components were detected by GC-MS analysis with high phenolic contents and high DPPH scavenging activity. In vivo results revealed that rats treated with STZ showed a highly significant elevation in blood glucose and a decrease in insulin hormone levels. Thiobarbituric acid-reactive substances and hydrogen peroxide levels were elevated, while bodyweight, enzymatic, and nonenzymatic antioxidants were significantly decreased. Furthermore, histopathological and immunohistochemical insulin expression, besides ultrastructure microscopic variations (β-cells, α-cells, and δ-cells), were seen in pancreas sections supporting the obtained biochemical changes. Otherwise, rats supplemented with ADAE alone showed an improved antioxidant status and declined lipid peroxidation. Moreover, diabetic rats augmented with ADAE showed significant modulation in oxidative stress markers and different pancreatic tissue investigations compared to diabetic ones. Conclusively, ADAE has a potent antioxidant and hypoglycemic influence that may be utilized as a health-promoting complementary therapy in diabetes mellitus.

Gymnemic acid protects murine pancreatic β-cells by moderating hyperglycemic stress-induced inflammation and apoptosis in type 1 diabetic rats

Type 1 diabetes is a chronic immune-mediated disease caused by pancreatic β-cell dysfunction with consequent severe insulin deficiency. Exacerbated blood glucose levels can cause oxidative stress in the pancreatic β-cells, which leads to inflammation, and apoptosis resulting in islet dysfunction. Although massive studies have been carried out to elucidate the causative factors for β-cell damage in diabetes, the therapeutic approach to pancreatic β-cell damage has not been extensively studied. Hence, the present study has been designed to delineate the role of gymnemic acid (GA) in protecting pancreatic β-cells in diabetic animals, with special reference to inflammation and apoptosis. Our data revealed that the treatment with GA significantly reverted the alteration in both biochemical and histochemical observations in young diabetic rats. Moreover, treatment with the GA downregulates the expression of proinflammatory markers (nuclear factor-κB, tumor necrosis factor-α, interleukin-[IL]-6, and IL-1β), proapoptotic proteins (Bax, cytochrome c, and cleaved caspase-3), as well as upregulates the expression of antiapoptotic protein Bcl-2 in diabetic rats. These findings suggest that the anti-inflammatory and antiapoptotic nature of GA mitigates β-cell damage in hyperglycemic rats.

Hepatoprotective Effect of Actinidia deliciosa against Streptozotocin-Induced Oxidative Stress, Apoptosis, and Inflammations in Rats

The present research intended to assess the possible protective and hypoglycemic effect of Actinidia deliciosa fruit aqueous extract (ADAE) in diabetic rats. The scavenging antioxidant capabilities of ADAE were evaluated using GC-MS analysis. In addition, rats were divided into four groups: control, ADAE, streptozotocin-induced DM (STZ), and STZ-treated rats + ADAE in an in vivo investigation. GC-MS analysis of ADAE was shown to include major components with high total phenolic contents and high DPPH scavenging activity. In diabetic rats, significant elevation in blood glucose level, lipid peroxidation, bilirubin, and lactate dehydrogenase activity as well as a change in lipid profile was observed, while insulin, body and liver weights, enzymatic and nonenzymatic antioxidants, liver function biomarkers, and protein content were significantly decreased. Furthermore, changes in the expression of the peroxisome proliferator-activated receptor (PPAR-γ), apoptotic, and inflammation-related genes were found. In addition, histological differences in rat liver tissue architecture were discovered, corroborating the biochemical modifications. However, consuming ADAE alone reduced lipid peroxidation and improved antioxidant status. Furthermore, diabetic rats given ADAE showed significant reductions in oxidative stress indicators and biochemical parameters, as well as improved tissue structure, when compared to the diabetic rats’ group. Also, ADAE supplementation protects diabetic rats’ hepatic tissue by upregulating PPAR-γ and downregulating apoptotic and inflammatory-related gene expression. In conclusion, A. deliciosa has beneficial protective effects so, it might be used as a complementary therapy in diabetes mellitus.

Salvia hispanica L. seeds extract alleviate encephalopathy in streptozotocin-induced diabetes in rats: Role of oxidative stress, neurotransmitters, DNA and histological indices

CONTEXT

Diabetes mellitus (DM) is a metabolic disorder and may lead to cognitive dysfunctions.

OBJECTIVE

The aim of this work is to evaluate the potency of Salvia hispanica L. seeds (S. hispanica L.) (chia seeds) petroleum ether extract in attenuating brain complications associated with streptozotocin (STZ) induced diabetes in rats.

MATERIALS AND METHODS

Phytochemical composition of the seeds extract, macro and micro elements, vitamins, protein, carbohydrate and caloric values were estimated. Diabetes was induced by a single intraperitoneal injection of STZ (60 mg/kg body weight (b.wt)). Glibenclamide as a reference drug was also evaluated. The biochemical evaluation was done by measuring levels of glucose, insulin, α amylase, glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA), dopamine (DA), serotonin (5-HD), noradrenaline (NE), acetylcholinesterase (AchE), tumor necrosis factor-α (TNF-α), DNA fragmentation pattern and the histopathological profile of the brain hippocampus region.

RESULTS

Gas chromatography/mass spectrometry (GC/MS) analysis revealed the presence of twenty-five fatty acid esters and twenty-two compounds. Column chromatography led to the isolation of nine compounds. Treatment with the seeds extract revealed improvement of the measured parameters with variable degrees.

CONCLUSION

Chia seeds extract succeeded to attenuate the neurodegeneration in diabetic rats. Thereafter, it could be potentially used as a new dietary supplement against diabetic encephalopathy.

Ameliorative effect of rubiadin-loaded nanocarriers in STZ-NA-induced diabetic nephropathy in rats: formulation optimization, molecular docking, and in vivo biological evaluation

Diabetic nephropathy (DN) is a significant source of end-stage renal illness all over the world in both developed and developing countries. The aim of the study was to optimize rubiadin-loaded niosomes (RLN) using Box-Behnken design for the management of streptozotocin-nicotinamide (STZ-NA)-induced DN in Wistar rats. The RLN were formulated by a "thin-layer hydration technique." The optimization of RLN was done by Box-Behnken design; the independent variables were cholesterol (CHOL), Span 80, and methanol, while the dependent factors were the vesicle size, zeta potential, and entrapment efficiency. The optimized formulation was characterized for various biochemical parameters including anti-diabetic activity in Wistar rats. The optimized RLN presented vesicle size of 238 nm, zeta potential -68 mV, and entrapment efficiency 85%. A noteworthy decreased in blood glucose level was detected in STZ-NA-induced DN rats when orally treated with RLN (100 mg/kg/week and 200 mg/kg/week). Oral administration of RLN formulation considerably decreased the levels of urea, uric acid, and creatinine in DN rats. In addition, treatment of DN rats with RLN formulation considerably improves the level of TBARS, GSH, SOD, and CAT. The lipid profile of DN rats was also improved on treatment with RLN formulation. This study revealed that the prepared RLN formulation was successfully optimized by Box-Behnken design and found to be useful for the management of STZ-NA-induced DN in Wistar rats.

Gymnemic Acid Ameliorates Pancreatic β-Cell Dysfunction by Modulating Pdx1 Expression: A Possible Strategy for β-Cell Regeneration

BACKGROUND

Endogenous pancreatic β-cell regeneration is a promising therapeutic approach for enhancing β-cell function and neogenesis in diabetes. Various findings have reported that regeneration might occur via stimulating β-cell proliferation, neogenesis, or conversion from other pancreatic cells to β-like cells. Although the current scenario illustrates numerous therapeutic strategies and approaches that concern endogenous β-cell regeneration, all of them have not been successful to a greater extent because of cost effectiveness, availability of suitable donors and rejection in case of transplantation, or lack of scientific evidence for many phytochemicals derived from plants that have been employed in traditional medicine. Therefore, the present study aims to investigate the effect of gymnemic acid (GA) on β-cell regeneration in streptozotocin-induced type 1 diabetic rats and high glucose exposed RIN5-F cells.

METHODS

The study involves histopathological and immunohistochemical analysis to examine the islet's architecture. Quantitative polymerase chain reaction (qPCR) and/or immunoblot were employed to quantify the β-cell regeneration markers and cell cycle proliferative markers.

RESULTS

The immunoexpression of E-cadherin, β-catenin, and phosphoinositide 3-kinases/protein kinase B were significantly increased in GA-treated diabetic rats. On the other hand, treatment with GA upregulated the pancreatic regenerative transcription factor viz. pancreatic duodenal homeobox 1, Neurogenin 3, MafA, NeuroD1, and β-cells proliferative markers such as CDK4, and Cyclin D1, with a simultaneous downregulation of the forkhead box O, glycogen synthase kinase-3, and p21^cip1 in diabetic treated rats. Adding to this, we noticed increased nuclear localization of Pdx1 in GA treated high glucose exposed RIN5-F cells.

CONCLUSION

Our results suggested that GA acts as a potential therapeutic candidate for endogenous β-cell regeneration in treating type 1 diabetes.

Effects of alcoholic extract of Terminalia Chebula dried fruit on blood biochemical profile in diabetic rats

Background

A considerable amount of attention has been recently paid to the discovery of effective natural antidiabetic drugs. Terminalia chebula is considered as the mother of herbs, with reported antidiabetic activity. This study aims to evaluate the renal and hepatic protective profile of its antidiabetic therapeutic doses.

Methods

To achieve the aim of the study, a total of 66 adult male rats of Sprague-Dawley species weighing about 180-200 g (weighed using a digital scale) were used. Type 2 diabetes mellitus (T2DM) was induced in using streptozotocin (STZ), rats were given a 5% dextrose solution for the next 24 h. Subjects received oral treatment of Terminalia chebula ethanolic extract at different doses (200, 400, and 600 mg/kg body weight) for 28 days. Measurements of fasting blood glucose level, change in body weight, lipid profile, serum liver enzymes, serum renal parameter, and histopathology of liver and kidney were carried out.

Results

Higher doses of Terminalia chebula (600 mg/Kg) were shown to have a potential therapeutic effect as well as the most prominent antidiabetic, antilipidemic activity, hepatoprotective and renoprotective profiles when compared to lower doses.

Conclusion

The use of Terminalia chebula alone or in combination with conventional antidiabetic drugs may be beneficial as a new advent therapy for diabetes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-021-00951-8.

The effect of etanercept and anakinra on experimental type 2 diabetes pathology in rats

In this study, the effects of etanercept, anakinra, and their combination on streptozotocin-induced type 2 diabetes in rats were pathologically evaluated. A total of 30 rats were separated into 5 groups as control (C), diabetes (D), diabetes + anakinra (DA), diabetes + etanercept (DE), and diabetes + anakinra + etanercept (DAE). Anakinra (10 mg/kg/day, s.c.) and etanercept (10 mg/kg, twice weekly, s.c.) were administered to the DA and DE groups, respectively, and the DAE group received both anakinra and etanercept for 21 days. Histopathologically, pathological changes related to diabetes in internal organs occurred in the diabetes group, and there was a significant decrease (improvement) in these changes in the treatment groups (P < 0.05). There was no significant difference (P > 0.05) between the treatment groups, but some changes in the liver and kidneys were higher in the combined group which should be taken into account for longer use. Although there was no significant difference, etanercept was more effective on pancreatic lesion scores and anakinra was more effective on testicular changes. As a result, the single or combined use of IL-1 and TNF-α antagonists anakinra and etanercept were effective in the treatment of type 2 diabetes in rats without any toxic-pathological effect.

Sinapic acid ameliorates cardiac dysfunction and cardiomyopathy by modulating NF-κB and Nrf2/HO-1 signaling pathways in streptozocin induced diabetic rats

Hyperglycemia and hyperlipidemia-arbitrated mitochondrial oxidative insult is key reason for cardiac dysfunction and cardiomyopathy. Sinapic acid (SA) is a hydroxycinnamic acid (a polyphenolic acid) present in multiple plants and possesses several pharmacological activities. In this study, we examined the cardio protective effects of SA on streptozotocin (STZ)-induced cardiac insults. STZ and both STZ induced diabetes and normal control rats were administered with 20 and 40 mg/kg SA for 12 weeks. STZ rats demonstrated hyperglycemia and hyperlipidemia. Additionally, STZ administered rats exhibited various histological changes in the cardiac muscles and significantly enhanced CK-MB and LDH. The significant enhancement of oxidative stress, inflammation, and apoptotic markers, and the capacity to curb oxidative stress was significantly abridged in the STZ induced diabetic heart. Chronic treatment with SA (20-40 mg/kg) ameliorated the increased level of glucose, lipid, and cardiac function markers and curtailed histological changes in the cardiac muscles. Chronic treatment also repressed inflammation, oxidative stress and apoptosis thereby and restoring antioxidant defenses in the myocardium of STZ induced diabetic rats. STZ induced cardiac dysfunction and cardiomyopathy by promoting inflammation and oxidative stress. Sinapic acid ameliorates cardiac dysfunction and cardiomyopathy via improvement of hyperglycemia, hyperlipidemia, inflammation, oxidative stress, and apoptosis. Thus, SA possesses possible therapeutic value for the prevention of diabetic cardiac dysfunction and cardiomyopathy via the NRF2/HO-1 and NF-κB pathways.

Glycyrrhiza glabra alcoholic root extract ameliorates hyperglycemia, hyperlipidemia, and glycation-induced free iron-mediated oxidative reactions

Hyperglycemia-associated oxidative stress leads to various pathophysiological complications in diabetes mellitus. Here, the effects of Glycyrrhiza glabra (G. glabra) root extract of streptozotocin (STZ)-induced diabetic changes and the associated free iron-mediated oxidative reactions were investigated. The animals were divided into five group, Group 1: Control (NC received buffer); Group 2: STZ-induced (DC); Group 3: Control treated with G. glabra root extract (NT, 60 mg/Kg b.w daily for 1 month); Group 4: Diabetic treated with the extract (60 mg/Kg b.w daily for 1 month); Group 5: Diabetic treated with glibenclamide (DTG, 8.6 mg/Kg b.w for 1 month). STZ (i) induced hyperglycemia, abnormal intraperitoneal glucose tolerance test (IPGTT), increased HbA_1c and decreased plasma insulin levels (ii) hyperlipidemia (iii) lowered antioxidant enzyme activities (iv) diminished RBC membrane fluidity (v) enhanced hemoglobin glycation-induced iron release and associated free radical reactions. Treatment with the extract resulted in significant reversal of hyperglycemia (DC: 205.0 ± 7.0 mg/dl vs. DT: 87.5 ± 4.5 mg/dl, p < .05); HbA_1c (DC: 11.5 ± 2.0 vs. DT: 7.5 ± 0.8 vs. DT: 7.5 ± 0.8, p < .05); insulin (DC: 0.3 ± 0.06 vs. DT: 1.25 ± 0.15 μgm/L, p < .05); free iron (DC: 150.4 ± 7.07 vs. DT: 98.8 ± 7.7 μgm/gm of Hb, p < .05); TBARS (DC + H₂ O₂ : 24.62 ± 11.30 vs. DC + H₂ O₂ : 9.82 ± 2.56 mmoles/h, p < .05); carbonyl (DC: 40.40 ± 1.57 vs. DT: 25.50 ± 1.12 mmoles/g of Hb, p < .05) levels and β-cell count/pancreatic islet (DC: 85 ± 15 vs. DT: 125 ± 20, p < .05). Thus, G. glabra extract is quite effective against hyperglycemia and the associated free iron-mediated oxidative stress. PRACTICAL APPLICATIONS: Chronic use of oral hypoglycemic synthetic drugs may produce side effects and drug resistance. Recently, various plant extracts are being researched to explore their antihyperglycemic potential. Here, the effects of this alcoholic powdered root extract on STZ-induced diabetic changes and associated oxidative stress, including hemoglobin-induced free iron-mediated oxidative reactions were examined. The STZ-induced diabetic changes and hemoglobin-glycation-induced free iron-mediated oxidative reactions were alleviated in the Wistar rats after 1-month of treatment with the extract. We have also reported previously that glycyrrhizin, a bioactive constituent of Glycyrrhiza glabra root inhibits peroxidase, esterase activities of hemoglobin and hemoglobin-mediated oxidative damage without affecting oxygen-binding capacity of the protein. This preclinical work further substantiates the potential therapeutic use of the G. glabra whole root extract in the treatment of diabetes mellitus.

Therapeutic effects of Chinese herbal medicines and their extracts on diabetes

With the improvement of people's living standards and changes in the environment, the incidence of diabetes has increased rapidly. It has gradually become one of the main diseases threatening the health and life of modern people, bringing a great burden to the society. Although the existing treatment methods can effectively control the symptoms of diabetes and delay its progression, they have not brought satisfactory improvement in the quality of life and treatment of patients. Traditional Chinese herbal medicines and their extracts combine thousands of years of experience and the scientific basis provided by modern experimental research, which is expected to bring a qualitative leap in the clinical management of diabetes. Therefore, this article systematically reviews studies on the effects of Chinese herbal medicine and its extracts on diabetes and its complications, and aims to bring new ideas and options for the clinical treatment of diabetes.

Potential of karamunting (Rhodomyrtus tomentosa) fraction against kidney damage in diabetic rats

Introduction: Karamunting (Rhodomyrtus tomentosa) is Indonesian native plant that contains high anti-oxidant compounds with the potential to suppress oxidative stress activity in cells. This study is the first research to specifically explore the role of the karamunting fraction in protecting kidney damage due to the formation of AGEs in the renal glomerulus in diabetes mellitus.

Objective: This study aims to assess the impact of karamunting on blood glucose profile, HbA1c, insulin profile and kidney condition (AGEs expression, TNF-α and kidney histology) in diabetic rats.

Methods: The karamunting extraction process was carried out by maceration with ethanol. Induction of diabetes mellitus was carried out using streptozotocin. Thirty male rats (Rattus norvegicus), Wistar strain weighing between 200–250 grams were the subject in this study. HbA1c, insulin, TNF-α, AGEs levels were evaluated in the kidney tissue. Histological assessment of the kidney was carried out.

Results: Karamunting can improve blood glucose levels in diabetic rats. This improvement in blood glucose levels causes an improvement in the level of HbA1c. Administration of karamunting fraction can prevent AGEs deposition in renal tissue, which in turn will inhibits the inflammation and prevents further damage of kidneys.

Conclusion: Karamunting fraction can improve blood glucose regulation so that it can prevent further damage and complications of kidney organs in diabetic rats.

Antidiabetic and antioxidant activity of phlorotannins extracted from the brown seaweed Cystoseira compressa in streptozotocin-induced diabetic rats

Diabetes mellitus is considered a set of diseases that lead to high glucose level due to the absolute or relative absence of insulin. The study investigated the antioxidant activity and antidiabetic effect of phlorotannins extracted from brown seaweed Cystoseira compressa. Phlorotannins were extracted from C. compressa. It was confirmed by 2,4 dimethoxy benzaldehyde assay (DMBA), ultraviolet spectra, Fourier transform infrared spectroscopy, and ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The free radical scavenging activity of phlorotannins was estimated by total antioxidant capacity, 1,1-diphenyl-2-picrylhydrazyl radical-scavenging activity, and 2,2 azino-bis3-ethylbenthiazoline-6-sulfonic acid assays. Four groups of albino rats used in this study include control normal, control phlorotannins extract, diabetic by intraperitoneally administering of streptozotocin, and diabetic treatment with 60 mg/kg of phlorotannin extract after 4 weeks of diabetes induction. The main compound identified by UPLC-MS/MS in C. compressa extract belonged to the fuhalol. C. compressa extract showed high antioxidant properties. Phlorotannins significantly decreased serum glucose, liver malondialdehyde, and α-amylase, glucosidase activities. However, total antioxidant capacity, serum insulin, hepatic glutathione, and AMPKα2 expression in skeletal muscle were improved compared to the diabetic group. The histopathological examination showed that phlorotannins markedly reduced damage in β cells of pancreases. Phlorotannins from C. compressa have efficient antioxidant activity and the antidiabetic effect that may be utilized in human health.

Thymoquinone, the Most Prominent Constituent of Nigella Sativa, Attenuates Liver Damage in Streptozotocin-Induced Diabetic Rats via Regulation of Oxidative Stress, Inflammation and Cyclooxygenase-2 Protein Expression

Diabetes mellitus (DM) is a multifaceted metabolic disorder that results in dysfunction and failure of various organs. The present study aimed to evaluate the role of Thymoquinone (TQ), on antidiabetic, oxidative stress, and anti-inflammatory activities in streptozotocin (STZ)-induced (55 mg/kg b.w) diabetic rats. TQ was orally given for 8 consecutive weeks at dose of 150 mg/kg b.w. The blood glucose, insulin, total cholesterol, triglycerides, liver function enzymes, high density lipoprotein (HDL)-cholesterol, and low-density lipoprotein (LDL)-cholesterol levels were measured accordingly in control, diabetes control (DC), and TQ-treatment groups. These experiments confirmed that TQ conserves the insulin level (0.4 ng/mL vs. 0.23 ng/mL), fasting blood glucose (146 ± 7 mg/dL vs. 225 ± 5 mg/dL), and HbA1c (7.5% vs. 10.6%) quite considerably as compared to DC animals. Our results also confirmed that TQ treatment conserves the body weight and lipid profile significantly in STZ-treated animals as compared to the DC group. Moreover, the antioxidant enzymes (GSH, SOD, GST, and CAT) levels decreased, liver function enzymes (ALT, AST, and ALP), lipid peroxidation and inflammatory markers (TNF-α, CRP, IL-1β, IL-6) increased by STZ treatment, that is significantly restored after TQ treatment. As compared to untreated animals, TQ restored the hepatocytes architectural changes and collagen fibers and cox-2 protein expression in liver tissues as evaluated by hematoxylin and eosin, Masson’s trichrome, and immunohistochemistry staining. Taken together, all these findings indicated that TQ ameliorates glucose level and lipid metabolism. It restores liver function, antioxidant enzymes, anti-inflammatory markers, and maintains hepatocytes architecture in STZ-induced diabetes mellitus rats. Here, in this study, we have demonstrated for the first time the role of TQ in the reduction of the expression of cyclooxygenase-2 and fibrosis formation in diabetic rats. Based on the findings, the study suggests that TQ is a novel natural drug with a wide range of clinical applications including the management of diabetes mellitus.

Nephroprotective effect of Vanillic acid in STZ-induced diabetic rats

Purpose

To investigate the protective effect of vanillic acid (VA) in streptozotocin (STZ)-induced diabetic nephropathy (DN) in rats.

Methods

Experimental diabetes mellitus in rats was induced by intraperitoneally administration of single dose of STZ (55 mg/kg). The animals were divided into 5 groups viz., normal control, diabetic control, glimepiride (0.5 mg/kg, orally) and VA treatment (50 and 100 mg/kg, orally) groups. The treatment was started after the confirmation of hyperglycemia (> 250 mg/dl) and continued for 6 weeks. Serum glucose level, and body weight were measured weekly. At the end of study, HbA1c in whole blood, insulin, lipid profile, urea, creatinine and albumin in serum. Creatinine and albumin were measured in urine along with creatinine clearance. In addition, kidney weight and histopathology were assessed.

Results

Treatment with VA markedly attenuated STZ-induced body weight loss and hyperglycemia, along with improved lipid profile and HbA1c, without significant alteration of serum insulin levels. It also decreased urea, creatinine and increased albumin in serum. Moreover, VA, significantly reduced urine volume, urinary albumin along with marked improvement in creatinine clearance. Further, the VA treatment significantly reverse the raised levels of oxidative stress markers, pro-inflammatory and fibrotic markers viz. TNF-α, IL-1β, IL-6, TGF-β1 and NFκB activity in kidney tissue. These effects are associated with amelioration of histopathological alterations compared to diabetic control rats. While glimepiride produced similar antihyperglycemic effect but the effect on albuminuria, oxidative stress markers and cytokine levels were less significant as compared to VA (100 mg/kg).

Conclusions

In conclusion, VA exhibited nephroprotective effect through amelioration of kidney dysfunction and damage in diabetic rats. The observed nephroprotective effect of VA may be ascribed to inhibition of hyperglycemia induced oxido-inflammatory stress and necroptosis of renal tissue possibly due to its antihyperglycemic, antioxidant and anti-inflammatory actions.

Ginkgo biloba delays light-induced photoreceptor degeneration through antioxidant and antiapoptotic properties

Intense exposure to artificial bright light increases the risk of retinal damage resulting in blurred vision and blindness. Long-term exposure to bright light elevates oxidative stress-induced apoptosis, which results in photoreceptor cell degeneration. However, to the best of our knowledge, the molecular mechanism associated with light-induced retinopathy remains unclear. In the present study, the mechanisms involved in light-induced oxidative stress and apoptosis were investigated along with the protective effects of Ginkgo biloba (EGb 761) in photoreceptor cell degeneration. EGb 761 was administered to mice at a dose of 50 or 100 mg/kg for 7 days prior to exposure to bright light (5,000 lux for 24 h). Furthermore, photoreceptor cell disorders were evaluated using electroretinogram (ERG) and H&E staining analyses. The expression levels of antioxidant genes and proteins ERK, thioredoxin (Trx) and nuclear factor erythroid 2-related factor 2 (Nrf-2) and the induction of apoptosis cytochrome c (Cyc), cleaved caspase-3 and Bax, were determined by reverse transcription-quantitative PCR and western blotting. ERG and histological analysis revealed that exposure to bright light induced functional and morphological changes to the photoreceptor cells. Exposure to bright light increased the levels of Cyc, cleaved caspase-3 and Bax, and decreased the levels of phosphorylated (p-) Erk, Nrf-2 and thioredoxin (Trx). However, treatment of mice with EGb 761 increased the expression levels of antiapoptotic (Bcl-2) and antioxidant (p-Erk, Trx and Nrf-2) proteins and decreased the expression levels of the apoptotic genes (Cyc, cleaved caspase-3 and Bax). Based on these findings, the present study suggested that prolonged exposure to light induces photoreceptor cell degeneration, where EGb 761 treatment may serve a therapeutic effect on the development of photoreceptor cell degeneration.

Ginkgo biloba extract (GbE) attenuates obesity and anxious/depressive-like behaviours induced by ovariectomy

While several pieces of evidence link obesity and mood disorders in menopause, the mechanisms involved are not yet fully understood. We have previously demonstrated that Ginkgo biloba extract (GbE) both attenuated diet-induced obesity of male rats and restored serotonin-induced hypophagia in ovariectomized female rats. The present study aimed at exploring whether GbE treatment ameliorates ovariectomy-related obesity and anxious/depressive-like behaviours. Wistar female rats were either ovariectomized (OVX) or sham-operated (Sham). After 2 months, either 500 mg/kg of GbE or vehicle were administered daily by gavage for 14 days. Anxious/depressive-like behaviours were assessed by the Elevated Plus Maze and the Forced Swim Tests, respectively. Ovariectomy caused high visceral adiposity, hyperleptinemia, and hypercholesterolemia, and increased the anxiety index (p = 0.048 vs. Sham + GbE) while it decreased the latency to immobility (p = 0.004 vs. Sham). GbE treatment in OVX rats improved body composition, adiponectin levels and blood lipid profile. It also reduced the anxiety index (p = 0.004) and increased the latency to immobility (p = 0.003) of OVX rats. Linear regression analysis demonstrated that leptin (p = 0.047) and total cholesterol levels (p = 0.022) were associated with anxious-like behaviours while body adiposity (p = 0.00005) was strongly associated with depressive-like behaviours. The results showed that GbE therapy was effective in attenuating the deleterious effects of ovariectomy on body composition, lipid profile, and anxious/depressive-like behaviours. Further studies are warranted to better understand the therapeutic potential of GbE in menopause.

Curative Effect of Catechin Isolated from Elaeagnus Umbellata Thunb. Berries for Diabetes and Related Complications in Streptozotocin-Induced Diabetic Rats Model

In this study, catechin (CTN) isolated from Elaeagnus umbellata was evaluated for in vitro antioxidant potential and inhibition of carbohydrate digestive enzymes (α-amylase and α-glucosidase). The compound was also tested for its in vivo antidiabetic potential using Sprague-Dawley rats as experimental animals. The effects of various doses of catechin in STZ (Streptozotocin) induced diabetic rats on fasting blood glucose level, body weight, lipid parameters, hepatic enzymes, and renal functions were evaluated using the reported protocols. The CTN exhibited the highest percent antioxidant for free radical scavenging activity against DPPH and ABTS free radicals, and inhibited the activity of carbohydrate digestive enzymes (with percent inhibition values: 79 ± 1.5% α-amylase and 80 ± 1.1% α-glucosidase). Administration CTN and standard glibenclamide significantly decreased the fasting blood glucose level and increased the body weight in STZ-induced diabetic rats. CTN significantly decreased the different lipid parameters, hepatic, and renal function enzyme levels along with Hb1c level in diabetic rats, while significantly increasing the high-density lipoprotein (HDL) level with values comparable to the standard glibenclamide. Further, the altered levels of glutathione and lipid peroxides of liver and kidney tissues were restored (by CTN) to levels similar to the control group. CTN significantly increased the antioxidant enzyme activities, total content of reduced glutathione, and reduced the malondialdehyde (MDA) level in rat liver and kidney tissues homogenates, and also corrected the histopathological abnormalities, suggesting its antioxidant potential.

New Insight into the Mechanisms of Ginkgo Biloba Extract in Vascular Aging Prevention

BACKGROUND

Aging-associated vascular dysfunction promotes cardiovascular diseases. Recently, Ginkgo biloba extract (GBE) has attracted considerable attention in the prevention of aged vasculature.

METHODS

This review discusses the pathophysiological alterations in aged vasculature and the underlying mechanisms of GBE in vascular aging suppression.

RESULTS

Both arterial stiffening and endothelial dysfunction are critical aging-related vascular phenotypes that result in the progression of cardiovascular diseases in the general population. Consistent oxidative stress and inflammatory reaction lead to vascular dysfunction. GBE ameliorates aging-related vascular dysfunction, due to its antioxidant and anti-inflammatory properties. The main effects of GBE in aged vasculature might be associated with the longevity signaling pathways. GBE also attenuates the progression of vascular aging in diabetes mellitus via regulation of glucose and lipid metabolism.

CONCLUSION

GBE plays an important role in the prevention of vascular aging process. It is a promising therapeutic approach to ameliorate aging-related vascular dysfunction and cardiovascular diseases.

Herbal Medicine for Slowing Aging and Aging-associated Conditions: Efficacy, Mechanisms and Safety

Aging and aging-associated diseases are issues with unsatisfactory answers in the medical field. Aging causes important physical changes which, even in the absence of the usual risk factors, render the cardiovascular system prone to some diseases. Although aging cannot be prevented, slowing down the rate of aging is entirely possible to achieve. In some traditional medicine, medicinal herbs such as Ginseng, Radix Astragali, Ganoderma lucidum, Ginkgo biloba, and Gynostemma pentaphyllum are recognized by the "nourishing of life" and their role as anti-aging phytotherapeutics is increasingly gaining attention. By mainly employing PubMed here we identify and critically analysed 30 years of published studies focusing on the above herbs' active components against aging and aging-associated conditions. Although many plant-based compounds appear to exert an anti-aging effect, the most effective resulted in being flavonoids, terpenoids, saponins, and polysaccharides, which include astragaloside, ginkgolide, ginsenoside, and gypenoside specifically covered in this review. Their effects as antiaging factors, improvers of cognitive impairments, and reducers of cardiovascular risks are described, as well as the molecular mechanisms underlying the above-mentioned effects along with their potential safety. Telomere and telomerase, PPAR-α, GLUTs, FOXO1, caspase-3, bcl-2, along with SIRT1/AMPK, PI3K/Akt, NF-κB, and insulin/insulin-like growth factor-1 pathways appear to be their preferential targets. Moreover, their ability to work as antioxidants and to improve the resistance to DNA damage is also discussed. Although our literature review indicates that these traditional herbal medicines are safe, tolerable, and free of toxic effects, additional well-designed, large-scale randomized control trials need to be performed to evaluate short- and long-term effects and efficacy of these medicinal herbs.

Antidiabetic activity of corn steep liquor extract of Curculigo pilosa and its solvent fractions in streptozotocin-induced diabetic rats

The rhizome of Curculigo pilosa (CP) prepared with Corn steep liquor (CSL), is traditionally used in the treatment of diabetes mellitus. In this study, antidiabetic activity of the CSL extract and its fractions (butanol and methanol) were evaluated in streptozotocin-induced diabetic rats. Diabetes mellitus was induced by single intraperitoneal administration of streptozotocin (50 mg/kg) and diabetic rats were treated with 300 mg/kg bodyweight of the extract(s) for 28 days. Antidiabetic effect was monitored by plasma blood glucose, oral glucose tolerances test (OGGT), body weight and heamatological indices. Also serum urea, creatinine, cholesterol, high density lipoprotein, bilirubin, alkaline phosphatase, aspartate and alanine transaminases were evaluated. The levels of hepatic glutathione, catalase, superoxide dismutase, lipid peroxidation, nitric oxide and hydrogen peroxide were assessed; also histopathology of the hepatic tissues was examined. Oral administration of the extract resulted in significant (p < 0.05) reduction of plasma blood glucose (29.32% crude extract and 22.96% butanol fraction) and also increased body weight (20.61% crude extract, 13.44% butanol fraction and 6.23% methanol fraction) of diabetic rats. The heamotogical indices, plasma parameters and hepatic oxidative stress in diabetic rats were returned to near normalcy following treatment with the extract(s). The GC-MS analysis of the extract revealed the presence of stilbene, a proven antidiabetic agent, which might be responsible for the antidiabetic activity. The results obtained suggest that the CSL extract of CP could be used in management of diabetes mellitus thus providing scientific validation of its use as an antidiabetic agent.

Ginkgo biloba Extract Attenuates Methotrexate-Induced Testicular Injury in Rats: Cross-talk Between Oxidative Stress, Inflammation, Apoptosis, and miRNA-29a Expression

Ginkgo biloba leaf extract (GIN) is a popular Chinese herbal medicine. It has a nephroprotective effect against the nephrotoxicity induced by the chemotherapeutic agent methotrexate (MTX). This work was designed to explore the testicular protective role of GIN on MTX-induced testicular injury in a rat model. The experimental protocol lasted for 10 days for the 4 studied groups. First group: received saline (normal control, NC group). The second group was administered GIN (100 mg/kg/day) orally for 10 days (GIN C). Third group: injected with MTX (20 mg/kg ip) only on the fifth day (MTX group). Fourth group: administered GIN for 10 days with MTX injection on the fifth day (GIN+MTX group). MTX induced testicular injury as evident by a marked rise in the malondialdehyde (MDA) content, interleukin-6 (IL-6) and IL-1β protein levels, nuclear factor kappa-B (NF-κB) protein expression, bcl-2 associated × protein (Bax) mRNA expression, p53 mRNA and protein expressions, and miRNA29-a expression along with a marked decline in the serum level of testosterone and superoxide dismutase (SOD) content in testicular tissue in relation to the NC group. Moreover, histopathological testicular damage with a notable decrease in the Johnsen score together with a significant elevation in the testicular injury score was observed in the MTX group in comparison to the NC group. The administration of GIN ameliorated the biochemical changes as well as the testicular histopathological findings and scores. GIN could protect against MTX-induced gonadotoxicity by its antioxidant, anti-inflammatory, antiapoptotic activities plus the regulation of the miRNA-29a testicular expression.

Effects of Ginkgo biloba intake on cardiometabolic parameters in patients with type 2 diabetes mellitus: A systematic review and meta-analysis of clinical trials

Ginkgo biloba (GKB) may have a beneficial effect on cardiometabolic parameters in type 2 diabetes mellitus (T2DM), but the data is inconsistent. Therefore, the current systematic review and meta-analysis of clinical trials was conducted to assess the influence of GKB on cardiometabolic parameters in T2DM. Several online databases such as PubMed, Embase, Scopus, Web of Sciences, Google Scholar and Cochrane Library were systematically searched from inception up to September 2, 2019. Heterogeneity across included studies was assessed using the Cochran's Q statistic and I2 index. To pool weighted mean differences (WMDs) and the corresponding 95% confidence intervals (CIs) as summary effect size, we selected fixed or random-effects model according to the result of heterogeneity. Seven studies comprising 768 subjects were included in the present meta-analysis which resulted in a significant effect of GKB on hemoglobin A1c (HbA1c) (WMD = 0.26, 95% CI = [0.02, 0.50], p = .034) and serum HDL-cholesterol levels (WMD = 1.99, 95% CI = [0.19, 3.79], p = .030) with no significant publication bias. GKB can significantly modulate HbA1c and HDL-cholesterol levels. However, due to uncertainties related to the limited number of studies, it is too early to conclude whether GKB has any potential effects on the cardiometabolic factors in patients with T2DM or not.

Model for type 2 diabetes exhibits changes in vascular function and structure due to vascular oxidative stress and inflammation

We used a type 2 diabetes rat model produced by a high fat diet (HFD) followed by low dose streptozotocin (STZ) to study diabetic vasculopathy. Animals were evaluated for early vascular structural changes, endothelial function, inflammation, lipid profile and oxidative stress. We used 20 male Sprague-Dawley rats divided equally into control and diabetic groups. Diabetic rats were fed an HFD for 4 weeks, injected intraperitoneally with STZ, then sacrificed at week 15. Aortic endothelial nitric oxide synthase (eNOS), aortic superoxide dismutase (SOD), endothelial-dependent and independent relaxation and contraction, intima-media thickness (IMT), malondialdehyde (MDA) and tumor necrosis factor-alpha (TNF-α) were measured. Histopathological characteristics also were assessed. Diabetic rats exhibited higher fasting blood glucose (FBG), low density lipoprotein, total cholesterol and triglycerides compared to the control group. Aortic endothelium-dependent relaxation due to acetylcholine (ACh) was lower, while aortic endothelium-dependent contraction due to calcium ionophore and endothelium-independent contraction due to phenylephrine (PE) were higher for the diabetic group. eNOS expression was lower in the diabetic group compared to controls. IMT and MDA levels were increased, while SOD activity was decreased in the diabetic group compared to controls. TNF-α was higher in the diabetic group than for controls. Our type 2 diabetes model exhibited endothelial dysfunction associated with early vascular structural changes, dyslipidemia, increased vascular oxidative stress, and inflammation. Therefore, the model is suitable for studying diabetic atherosclerosis.

Molecular docking analysis and anti-hyperglycaemic activity of Synacinn™ in streptozotocin-induced rats

Synacinn™ is a standardized polyherbal supplement formulated from Cinnamomum zeylanicum Blume, Curcuma zanthorrhiza Roxb., Syzygium polyanthum (Wight) Walp., Orthosiphon stamineus Benth. and Andrographis paniculata (Burm.f.) Nees. It is designed for the synergistic treatment of diabetes mellitus and its complications. Although the beneficial effects are yet to be verified scientifically, it is traditionally used to improve general health in patients with diabetes. This study aimed to evaluate the anti-hyperglycemic effects of Synacinn™ in a streptozotocin-induced type 1 diabetes rat model. Initially, Synacinn™ was used for in vivo acute oral toxicity tests and 14 day repeated dose toxicity tests to determine the toxicity levels. An efficacy study of Synacinn™ was carried out via the oral administration of 10, 50, 100, 250, and 250 (b.i.d.) mg kg⁻¹ doses to streptozotocin-induced diabetic rats. After 28 days, blood serum was collected to measure the fasting blood glucose, triglyceride, cholesterol, alanine aminotransferase, alkaline phosphatase, creatinine, and uric acid levels. The liver, kidney, and pancreas structures were histopathologically analyzed. In silico binding interaction studies of five phytochemicals in Synacinn™ identified via HPLC with glucokinase were performed using molecular docking analysis. The results showed that although no mortality was observed during the acute oral toxicity tests, notable damage to the liver and kidney occurred during the 14 day repeated dose testing at Synacinn™ levels of 600 mg kg⁻¹ and 2000 mg kg⁻¹. Treatment with 250 mg kg⁻¹ (b.i.d.) Synacinn™ of the streptozotocin-induced type 1 diabetic rats significantly (p < 0.05) improved the fasting blood glucose (59%), triglyceride (58%), cholesterol (47%), alanine aminotransferase (60%), alkaline phosphatase (90%), and creatinine (32%) levels. Synacinn™ also improved the relative weights of liver (35%), kidney (36%), and pancreatic (36%) tissue. Histological analysis showed improvements in the conditions of the central vein of the liver, the kidney Bowman's capsule and glomerulus, and the pancreatic islets of Langerhans. HPLC analysis of a standardized extract identified five active phytochemicals: andrographolide (17.36 mg g⁻¹), gallic acid (11.5 mg g⁻¹), curcumin (2.75 mg g⁻¹), catechin (3.9 mg g⁻¹), and rosmarinic acid (5.54 mg g⁻¹). Molecular docking studies with glucokinase showed that andrographolide yields the highest binding energy (−12.1 kcal mol⁻¹), followed by catechin (−10.2 kcal mol⁻¹), rosmarinic acid (−8.6 kcal mol⁻¹), curcumin (−7.8 kcal mol⁻¹), and gallic acid (−5.6 kcal mol⁻¹). These current findings suggest that Synacinn™ at a dose of 250 mg kg⁻¹ was non-toxic to rats. A twice-daily 250 mg kg⁻¹ dose of Synacinn™ is an effective anti-hyperglycemic agent, lowering blood glucose, triglyceride, and cholesterol levels, and assisting the recovery of organ impairment caused by streptozotocin in type 1 diabetic rats.

Synacinn™, a standardized polyherbal supplement, was shown to improve hyperglycemic conditions and related complications in STZ-induced rats.

Sinapic Acid Ameliorates the Progression of Streptozotocin (STZ)-Induced Diabetic Nephropathy in Rats via NRF2/HO-1 Mediated Pathways

Diabetic neuropathy (DN) is a complicated inauspicious outcome of diabetes, like other abnormalities of diabetes the cause of DN is still vague and it may be the result of various pathological conditions leading up to end-stage renal failure. The present study examines the efficacy of sinapic acid (SA) in streptozotocin (STZ)-induced DN nephropathy and the linked pathway. Twenty-four rats were equally divided randomly into four categories: Normal control (NC), STZ, STZ + SA 20 mg/kg bw, and STZ + SA 40 mg/kg bw. After 8 weeks they were evaluated for ratio of renal index, the fasting blood glucose (FBG), blood urea nitrogen (BUN), 24 h urea protein, serum creatinine (SCr), reduced glutathione peroxidase (GPx), superoxide dismutase (SOD), lipid peroxidation (MDA), tumor necrosis factor α (TNFα), interleukin (IL)-6, as well as lipid profile total cholesterol (TC), total triglycerides (TG), very low density lipoprotein (VLDL), low density lipoprotein (LDL), and high density lipoprotein (HDL) levels. Additionally, histomorphology and ultrastructure of the kidneys were also assessed. Protein expression levels of transforming growth factor-β1 (TGF-β1), nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), IκBα protein (IkBα), anti-apoptotic protein BCl2, nuclear factor kappa B (NF-kB), and Bax were examined. We observed that SA 20 mg/kg bw and 40 mg/kg bw pretreatment significantly and dose-dependently upregulated the protein expression of HO-1, Nrf2, IKBα, and Bcl-2 but downregulated the protein expression of NF-κB, proposing that the nephroprotective mechanism of SA is due to its antioxidant and anti-inflammatory activity; SA prevents the release of cytokines and inflammatory markers (TNFα and IL-6), upregulates antioxidant defense enzymes, and reduces lipid peroxidation, as well as nitric oxide, and anti-apoptotic activity, which may be influenced by the regulation of TNF-α, IL-6, Bcl-2, NF-kB, and BaX via the Nrf2/HO-1 pathway in STZ induced DN. Thus, our results suggest that SA ameliorates the development of STZ-induced DN in rats via NRF2/HO-1 mediated pathways. Further comprehensive studies are required for complete elucidation of the fundamental mechanisms.

Herbal Medicine for Cardiovascular Diseases: Efficacy, Mechanisms, and Safety

Cardiovascular diseases (CVDs) are a significant health burden with an ever-increasing prevalence. They remain the leading causes of morbidity and mortality worldwide. The use of medicinal herbs continues to be an alternative treatment approach for several diseases including CVDs. Currently, there is an unprecedented drive for the use of herbal preparations in modern medicinal systems. This drive is powered by several aspects, prime among which are their cost-effective therapeutic promise compared to standard modern therapies and the general belief that they are safe. Nonetheless, the claimed safety of herbal preparations yet remains to be properly tested. Consequently, public awareness should be raised regarding medicinal herbs safety, toxicity, potentially life-threatening adverse effects, and possible herb–drug interactions. Over the years, laboratory data have shown that medicinal herbs may have therapeutic value in CVDs as they can interfere with several CVD risk factors. Accordingly, there have been many attempts to move studies on medicinal herbs from the bench to the bedside, in order to effectively employ herbs in CVD treatments. In this review, we introduce CVDs and their risk factors. Then we overview the use of herbs for disease treatment in general and CVDs in particular. Further, data on the ethnopharmacological therapeutic potentials and medicinal properties against CVDs of four widely used plants, namely Ginseng, Ginkgo biloba, Ganoderma lucidum, and Gynostemma pentaphyllum, are gathered and reviewed. In particular, the employment of these four plants in the context of CVDs, such as myocardial infarction, hypertension, peripheral vascular diseases, coronary heart disease, cardiomyopathies, and dyslipidemias has been reviewed, analyzed, and critically discussed. We also endeavor to document the recent studies aimed to dissect the cellular and molecular cardio-protective mechanisms of the four plants, using recently reported in vitro and in vivo studies. Finally, we reviewed and reported the results of the recent clinical trials that have been conducted using these four medicinal herbs with special emphasis on their efficacy, safety, and toxicity.

Effect of Ficus glomerata leaf extract in streptozotocin-induced early diabetic complications and its characterization by LC-MS

Diabetes mellitus is a complex metabolic disorder that leads to various micro-vascular complications. The present study elucidated the effect of chloroform extract of leaves of Ficus glomerata (CHFG) in streptozotocin-induced early diabetic renal and neural complications. Wistar rats were injected with STZ (55 mg/kg, i.p.) to produce experimental diabetes. Two weeks after the stabilization of diabetes, CHFG extract at the dose of 200 and 400 mg/kg (CHFG 200 and CHFG 400) and metformin at the dose of 250 mg/kg (Met 250) was administered to the diabetic rats for further two weeks. Diabetic rats showed an increase in blood glucose, plasma urea, uric acid, creatinine, triglyceride, and total cholesterol level. The change in behavioral parameters such as thermal hyperalgesia and cold allodynia with compromised sciatic nerve and kidney antioxidant status were seen in diabetic rats. Diabetic rats treated with CHFG 200, CHFG 400, and Met 250 showed a decrease in blood glucose, plasma urea, uric acid, creatinine, triglyceride, and total cholesterol level. Also, it improved altered behavioral parameters such as thermal hyperalgesia and cold allodynia. It also restored the sciatic nerve and kidney antioxidant status. The results of kidney and sciatic nerves histopathological study were in line with the results of biochemical parameters that confirmed the favorable role of CHFG. Characterization of CHFG by LC-MS revealed the presence of diverse phytoconstituents, which might be responsible for its protective effect.

Reduction of blood glucose by plant extracts and their use in the treatment of diabetes mellitus; discrepancies in effectiveness between animal and human studies

ETHNOPHARMACOLOGICAL RELEVANCE

The global problem of diabetes, together with the limited access of large numbers of patients to conventional antidiabetic medicines, continues to drive the search for new agents. Ancient Asian systems such as traditional Chinese medicine, Japanese Kampo medicine, and Indian Ayurvedic medicine, as well as African traditional medicine and many others have identified numerous plants reported anecdotally to treat diabetes; there are probably more than 800 such plants for which there is scientific evidence for their activity, mostly from studies using various models of diabetes in experimental animals.

AIM OF THE REVIEW

Rather than a comprehensive coverage of the literature, this article aims to identify discrepancies between findings in animal and human studies, and to highlight some of the problems in developing plant extract-based medicines that lower blood glucose in patients with diabetes, as well as to suggest potential ways forward.

METHODS

In addition to searching the 2018 PubMed literature using the terms 'extract AND blood glucose, a search of the whole literature was conducted using the terms 'plant extracts' AND 'blood glucose' AND 'diabetes' AND 'double blind' with 'clinical trials' as a filter. A third search using PubMed and Medline was undertaken for systematic reviews and meta-analyses investigating the effects of plant extracts on blood glucose/glycosylated haemoglobin in patients with relevant metabolic pathologies.

FINDINGS

Despite numerous animal studies demonstrating the effects of plant extracts on blood glucose, few randomised, double-blind, placebo-controlled trials have been conducted to confirm efficacy in treating humans with diabetes; there have been only a small number of systematic reviews with meta-analyses of clinical studies. Qualitative and quantitative discrepancies between animal and human clinical studies in some cases were marked; the factors contributing to this included variations in the products among different studies, the doses used, differences between animal models and the human disease, and the impact of concomitant therapy in patients, as well as differences in the duration of treatment, and the fact that treatment in animals may begin before or very soon after the induction of diabetes.

CONCLUSION

The potential afforded by natural products has not yet been realised in the context of treating diabetes mellitus. A systematic, coordinated, international effort is required to achieve the goal of providing anti-diabetic treatments derived from medicinal plants.

Protective effect of EX-527 against high-fat diet-induced diabetic nephropathy in Zucker rats

High-fat diet (HFD)-induced obesity is implicated in diabetic nephropathy (DN). EX-527, a selective Sirtuin 1 (SIRT1) inhibitor, has multiple biological functions; however, its protective effect against DN is yet to be properly understood. This study was aimed to explore the protective effect of EX-527 against DN in HFD-induced diabetic Zucker (ZDF) rats. After 21 weeks of continually feeding HFD to the rats, the apparent characteristics of progressive DN were observed, which included an increase in kidney weight (~160%), hyperglycemia, oxidative stress, and inflammatory cytokines, and subsequent renal cell damage. However, the administration of EX-527 for 10 weeks significantly reduced the blood glucose concentration and kidney weight (~59%). Furthermore, EX-527 significantly reduced the serum concentration of transforming growth factor-β1 (49%), interleukin (IL)-1β (52%), and IL-6 in the HFD-fed rats. Overall, the antioxidant activities significantly increased, and oxidative damage to lipids or DNA was suppressed. Particularly, EX-527 significantly reduced blood urea nitrogen (81%), serum creatinine (71%), microalbumin (43%), and urinary excretion of protein-based biomarkers. Histopathological examination revealed expansion of the extracellular mesangial matrix and suppression of glomerulosclerosis following EX-527 administration. EX-527 downregulated the expression of α-SMA (~64%), TGF-β (25%), vimentin, α-tubulin, fibronectin, and collagen-1 in the kidneys of the HFD-fed rats. Additionally, EX-527 substantially reduced claudin-1 and SIRT1 expression, but increased the expression of SIRT3 in the kidneys of the HFD-fed rats. EX-527 also inhibited the growth factor receptors, including EGFR, PDGFR-β, and STAT3, which are responsible for the anti-fibrotic effect of SIRT-1. Therefore, the administration of EX-527 protects against HFD-induced DN.

Folic acid and melatonin mitigate diabetic nephropathy in rats via inhibition of oxidative stress

Background

Diabetes mellitus is a global epidemic leads to multiple serious health complications, including nephropathy. Diabetic nephropathy is a serious kidney-related complication of type 1 or 2 diabetes that is prevalent in almost 40% of the people with diabetes. We examined whether folic acid and melatonin can reduce progression of nephropathy in rats of type 1 diabetes mellitus by controlling the level of oxidative stress, glucose, lipids, and cytokines.

Methods

Forty-two male albino rats were distributed into six groups, (n = 7 per group). Five of the groups were induced with diabetes by a single intraperitoneal injection of freshly prepared streptozotocin at a dose of 50 mg/kg body weight. After the induction of diabetes, the rats were treated with folic acid (100 mg/kg) and melatonin (10 mg/kg) separately and in combination daily for 6 weeks, whereas, the other diabetic group was treated with glibenclamide (5 mg/kg). One of the diabetic groups served as a positive control. One-way ANOVA was used to compare those five subfields ability followed by LSD multiple comparisons.

Results

The data indicated that diabetes significantly altered the body weight, lipids and kidney function. Diabetic rats exhibited a significant increase in plasma levels of urea, uric acid, creatinine, sodium, tumor necrosis factor alpha (TNF-α), interleukin-6(IL-6), cholesterol, triglycerides, and low-density lipoprotein (LDL). In contrast, plasma total protein, potassium, high-density lipoprotein (HDL) and interleukin-10 (IL-10) decreased significantly in diabetic rats compared to the control rats. Moreover, levels of renal malondialdehyde (MDA) and nitric oxide (NO) were significantly increased while the levels of renal glutathione(GSH), superoxide dismutase(SOD), and catalase (CAT) were significantly decreased in diabetic rats comparison to those in the control rats. Hence, diabetic rats treated with folic acid and melatonin alone as well as in combination showed improvements with respect to the indices in addition to a significant recovery observed via histopathology when compared to the diabetic group.

Conclusions

These results revealed that treatment with folic acid in combination with melatonin in diabetic rats was more effective than treatment with either of folic acid or melatonin alone to alleviate the symptoms of diabetic nephropathy.

Effect of ethanolic preparations of cinnamon (Cinnamomum zeylanicum) extract on hematologic and histometric parameters of selected organs in Alloxan® induced diabetic female albino rats

Purpose

Assessment of the antidiabetic effect of cinnamon bark extract in histologic damages and some hematologic parameters in Alloxan® induced diabetic female albino rats.

Method

Thirty female albino rats weighing 150-230 g were divided into five groups (n = 6): normal (G1) and diabetic groups (intraperitoneally Alloxan®-injected) including diabetic control (G2), Getformin @ 0.25 (G3), CE @ 0.10 (G4), and CE @ 0.20 g/kg b.wt. (G5) for 49 days. Blood glucose level and weight were measured on weekly interval for the period of seven weeks (49th day). Blood samples were collected for hematologic analysis. Tissue samples from uterus, liver and kidneys were processed by routine paraffine technique. Histologic sections of uterus were studied to measure endometrial glands area and thickness of endo- and myometrium. Liver and kidneys were evaluated for diabetes-induced degenerative changes and antidiabetic effect of cinnamon extract (CE). One-way analysis of variance followed by Tukey test were used to compare the group means for each parameter.

Results

Statistical analysis revealed significant (P < 0.05) deleterious effects of diabetes on all parameters studied, however, CE recovered hematological parameters significantly (P < 0.05) as seen in G3 and G5 groups which showed significant (P < 0.05) improvement in uterus, liver and kidneys' histology. G4 significantly (P < 0.05) reduced the blood glucose at the 4th week which was maintained in subsequent weeks while G3 and G5 had significantly (P < 0.05) lowered the blood glucose from 1st week, although highly significant (P < 0.01) effect was observed during last two weeks of the study.

Conclusion

Anti-diabetic activity of cinnamon extract was found significant in Alloxan® induced hyperglycemic rats in dose-dependent manners. CE has potential to restore diabetes induced hematological disturbances and histological damages in uterus, liver and kidney due to the presence of cinnamic acid, anhydride tannin and methyl-hydroxy chalcone polymer. Hence, CE can be recommended for the management of glucose homeostasis to avoid diabetes-associated disturbances in female rats.