Renoprotective effect ofBacopa monnieri viainhibition of advanced glycation end products and oxidative stress in STZ-nicotinamide-induced diabetic nephropathy

Shengqing Jiangzhuo capsule ameliorates diabetic nephropathy by improving Keap1/Nrf2 signaling pathway

BACKGROUND

Diabetic nephropathy (DN) is a major contributor to end-stage renal failure, and lacking effective treatment options. Shengqing Jiangzhuo capsule (SQJZJN), a traditional Chinese medicine prescription with known efficacy in chronic kidney disease, has not been thoroughly investigated for its potential in DN protection.

METHODS

Eight-week-old male C57BLKS/J db/db, C57BLKS/J db/m mice, and human glomerular mesangial cell (HMC) cells cultured with high glucose were used as experimental models in this study.

RESULTS

The in vivo investigation showed that SQJZJN can significantly ameliorate renal pathological damage, reduce serum creatinine, and lower urinary microalbumin levels in db/db mice. In vitro, SQJZJN treatment mitigated advanced glycation end products (AGEs) and reactive oxygen species (ROS), leading to a reduction in renal cell apoptosis. Mechanistically, SQJZJN activated the Keap1/Nrf2/ARE pathway by promoting nuclear factor erythroid-derived 2-related factor 2 (Nrf2), γ-glutamylcysteine synthetase heavy subunit (γ-GCS), and Heme oxygenase-1 (HO-1) expressions, while decreasing Kelch-like ECH-associated protein 1 (KEAP1) expressions.

CONCLUSION

These findings suggest that SQJZJN exerts a protective effect on DN, potentially through the activation of the Keap1/Nrf2/ARE pathway.

Cucurbita pepo seeds improve peripheral neuropathy in diabetic rats by modulating the inflammation and oxidative stress in rats

BACKGROUND

Cucurbita pepo (C. pepo) is cultivated and used traditionally as vegetable as well as medicine in different parts of the world. The aim of current study was to investigate the potential of C. pepo in attenuation of diabetic neuropathy via using streptozotocin (STZ)-induced diabetes model in male wistar rats.

MATERIALS AND METHODS

Diabetic neuropathy was induced by administration of STZ; 65 mg/kg, i.p. and Nicotinamide (NAD; 230 mg/kg i.p.) and assessed by measuring thermal hyperalgesia, mechanical hyperalgesia and motor nerve conduction velocity (MNCV) in experimental animals. Treatment with different doses of (100, 200 and 400 mg/kg, p.o.) petroleum ether extract of C. pepo (CPE) and hydroethanolic extract of C. pepo (CHE) was started from the 60th day of STZ/NAD administration and continued upto 90th day.

RESULTS

CPE and CHE significantly attenuated the behavioural changes including hyperalgesia, allodynia and MNCV linked to diabetic neuropathy. Moreover, the oxidative stress and level of TNF-α, TGF-β and IL-1β was found to be significantly attenuated in experimental animals.

CONCLUSION

Thus C. pepo might ameliorate the progression of diabetic neuropathy via modulation of chronic hyperglycemia and therefore and have therapeutic potential for treatment of diabetic neuropathic pain.

Translation Animal Models of Diabetic Kidney Disease: Biochemical and Histological Phenotypes, Advantages and Limitations

Animal models play a crucial role in studying the pathogenesis of diseases, developing new drugs, identifying disease risk markers, and improving means of prevention and treatment. However, modeling diabetic kidney disease (DKD) has posed a challenge for scientists. Although numerous models have been successfully developed, none of them can encompass all the key characteristics of human DKD. It is essential to choose the appropriate model according to the research needs, as different models develop different phenotypes and have their limitations. This paper provides a comprehensive overview of biochemical and histological phenotypes, modeling mechanisms, advantages and limitations of DKD animal models, in order to update relevant model information and provide insights and references for generating or selecting the appropriate animal models to fit different experimental needs.

Study on the mechanism of warming yang and reducing turbidity decoction in the treatment of diabetic kidney disease based on network pharmacology

This study aimed to investigate the mechanism of warming yang and reducing turbidity decoction in the treatment of diabetic kidney disease (DKD) by network pharmacology. The active components and corresponding targets of warming yang and reducing turbidity decoction were screened through the Traditional Chinese Medicine Systems Pharmacology database, DKD-related targets were obtained from Genecard and Online Mendelian Inheritance in Man databases, and drug-disease common targets were screened through Venny online website. Then we used STRING and Cytoscape software to analyze and perform protein-protein interaction network, and used CytoNCA plug-in to perform topological analysis to screen out the core target. We used RStudio to performed gene ontology (GO) functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. One hundred one active components in warming yang and reducing turbidity decoction participated in the regulation of the body's response to foreign bodies, lipopolysaccharides, metal ions, ketone bodies, hypoxia and oxidative stress by regulating 186 targets related to DKD, and played a role in the treatment of DKD by interfering with pathways such as interfered with lipids and atherosclerosis, PI3K-Akt, fluid shear stress and atherosclerosis, AGE-RAGE and cell senescence. It was implied that warming yang and reducing turbidity decoction had the features of multi components, multi targets and multi pathways in the treatment of DKD, which might create methods and directions for further verification of the molecular mechanism of warming yang and reducing turbidity decoction.

The Nicotinamide/Streptozotocin Rodent Model of Type 2 Diabetes: Renal Pathophysiology and Redox Imbalance Features

Diabetic nephropathy (DN) is a common complication of diabetes mellitus. While there has been a great advance in our understanding of the pathogenesis of DN, no effective managements of this chronic kidney disease are currently available. Therefore, continuing to elucidate the underlying biochemical and molecular mechanisms of DN remains a constant need. In this regard, animal models of diabetes are indispensable tools. This review article highlights a widely used rodent model of non-obese type 2 diabetes induced by nicotinamide (NA) and streptozotocin (STZ). The mechanism underlying diabetes induction by combining the two chemicals involves blunting the toxic effect of STZ by NA so that only a percentage of β cells are destroyed and the remaining viable β cells can still respond to glucose stimulation. This NA-STZ animal model, as a platform for the testing of numerous antidiabetic and renoprotective materials, is also discussed. In comparison with other type 2 diabetic animal models, such as high-fat-diet/STZ models and genetically engineered rodent models, the NA-STZ model is non-obese and is less time-consuming and less expensive to create. Given that this unique model mimics certain pathological features of human DN, this model should continue to find its applications in the field of diabetes research.

Using network pharmacology to explore the mechanism of Danggui-Shaoyao-San in the treatment of diabetic kidney disease

Danggui-Shaoyao-San (DSS) is one of traditional Chinese medicine, which recently was found to play a protective role in diabetic kidney disease (DKD). However, the pharmacological mechanisms of DSS remain obscure. This study would explore the molecular mechanisms and bioactive ingredients of DSS in the treatment of DKD through network pharmacology. The potential target genes of DKD were obtained through OMIM database, the DigSee database and the DisGeNET database. DSS-related targets were acquired from the BATMAN-TCM database and the STITCH database. The common targets of DSS and DKD were selected for analysis in the STRING database, and the results were imported into Cytoscape to construct a protein-protein interaction network. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways enrichment analysis and Gene Ontology (GO) enrichment analysis were carried out to further explore the mechanisms of DSS in treating DKD. Molecular docking was conducted to identify the potential interactions between the compounds and the hub genes. Finally, 162 therapeutic targets of DKD and 550 target genes of DSS were obtained from our screening process. Among this, 28 common targets were considered potential therapeutic targets of DSS for treating DKD. Hub signaling pathways including HIF-1 signaling pathway, TNF signaling pathway, AMPK signaling pathway, mTOR signaling pathway, and PI3K-Akt signaling pathway may be involved in the treatment of DKD using DSS. Furthermore, TNF and PPARG, and poricoic acid C and stigmasterol were identified as hub genes and main active components in this network, respectively. In this study, DSS appears to treat DKD by multi-targets and multi-pathways such as inflammatory, oxidative stress, autophagy and fibrosis, which provided a novel perspective for further research of DSS for the treatment of DKD.

Pharmacological attributes of Bacopa monnieri extract: Current updates and clinical manifestation

Bacopa monnieri has been used for centuries in Ayurvedic medicine, alone or in combination with other herbs, as a memory and learning enhancer, sedative, and anti-epileptic. This review aimed to highlight the health benefits of B. monnieri extracts (BME), focusing on anti-cancer and neurodegenerative diseases. We examined the clinical studies on phytochemistry and pharmacological application of BME. We further highlighted the mechanism of action of these extracts in varying types of cancer and their therapeutic implications. In addition, we investigated the underlying molecular mechanism in therapeutic interventions, toxicities, safety concerns and synergistic potential in cognition and neuroprotection. Overall, this review provides deeper insights into the therapeutic implications of Brahmi as a lead formulation for treating neurological disorders and exerting cognitive-enhancing effects.

Phenethyl isothiocyanate attenuates diabetic nephropathy via modulation of glycative/oxidative/inflammatory signaling in diabetic rats

Diabetic nephropathy (DN) is a diabetic complication characterized by disruption of renal microvasculature, reactive oxygen species accumulation and increased inflammation, all of which contribute to renal injury. Phenethyl isothiocyanate (PEITC) is a naturally occurring isothiocyanate well known for its antioxidant and anti-inflammatory effects, yet its reno-preventive effects against DN has not been investigated. The current study looked into the in vivo reno-protective effects of PEITC in STZ-induced DN in rats. PEITC (3, 10 and 30 mg/kg) was administered orally for 8 weeks post DM establishment. PEITC treatment significantly improved kidney and liver functions, renal histopathological features, tissue fibrosis, macrophage infiltration and blood glucose levels compared to DN control. Mechanistically, PEITC treatment alleviated DN-induced renal damage via modulating glycation and oxidative stresses and inflammatory response. As such, PEITC activated glyoxalase 1 (GLO1) that induced a retraction in renal tissue expression of advanced glycation end products (AGEs) and its receptor (RAGE). PEITC activated nuclear erythroid 2-related factor 2 (Nrf2) and increased expression of its downstream targets, hemeoxygenase-1 (HO-1) and gamma glutamate-cysteine (γ-GCS). Additionally, PEITC treatment decreased the expression of Nrf2 repressor protein, keap1. The anti-inflammatory effect of PEITC was driven, at least in part, via reducing the NLRP3 inflammasome activation as indicated by down regulation of NLRP3, TXNIP, capsase-1 and IL-1β, TNF-alpha and IL-6. In conclusion; PEITC attenuated DN progression in a dose dependent manner mainly via interruption of AGE/RAGE and NLPR3/TXNIP/NrF2 crosstalk.

Inhibitory Potential of Murraya Koenigii (L.) and Ficus Carica L. Extracts Against Aldose Reductase (ALR), Advanced Glycation End Products (AGEs) Formation and Sorbitol Accumulation

Introduction: Murraya koenigii (L.) and Ficus carica L. are traditionally used plants with significant medicinal and nutritional values. Aim and Objective: The present study was focused on the evaluation of hydro-alcoholic and aqueous extracts of M. koenigii (L.) leaves [MKHA (M. koenigii (L.) hydro-alcoholic extract) and MKAQ (M. koenigii (L.) aqueous extract)] and dried fruits of F. carica L. [FCHA (F. carica L. hydro-alcoholic extract) and FCAQ (F. carica L. aqueous extract)] in the attenuation of markers of microvascular complications associated with diabetes mellitus which can be further used to investigate the pharmacological activity of these plants in treatment of diabetes and its complications. Material and Method: The attenuating effect of the extracts was evaluated by calculating the ALR1 enzyme inhibition in a kidney of Wistar rat, anti-glycation activity in bovine serum albumin (BSA) and erythrocyte sorbitol accumulation inhibition in heparinized human blood. Results: A significant inhibitory effect (IC50 6.47μg/ml,7.26μg/ml,8.93 μg/ml and 9.66μg/ml) was observed with different concentrations of extracts (MKHA, MKAQ, FCHA and FCAQ) respectively, against ALR enzyme. After the 4th week of incubation, the inhibition of AGEs formation by MKHA, MKAQ, FCHA and FCAQ (500μg/ml) was found to be 82.58%, 78.58%, 74.39% and 69.56% respectively. MKHA, MKAQ, FCHA and FCAQ were found to exhibit significant inhibition against the accumulation of sorbitol in RBCs with IC50 188.88 μg/ml, 247.74μg/ml, 291.94μg/ml and 345.34μg/ml, respectively. Conclusion: The administration of different concentrations of MKHA, MKAQ, FCHA and FCAQ significantly attenuated ALR, AGEs and sorbitol accumulation; hence, it can provide a basis for identification and development of new inhibitors of these biomarkers.

Combination of pathological and spectroscopic characterization to promote diagnosis of retinal pigment epithelium-Bruch's membrane complex in a diabetic rat model

Diabetic retinopathy (DR) is a common condition of diabetes, and approaches to detecting early DR using the unique characteristics of the retinal pigment epithelium-Bruch's membrane complex (RBC) have increasingly attracted attention. A diabetic model was established in Sprague-Dawley rats via streptozocin (STZ) injection for 1 (DM1) and 6 months (DM6), confirmed by weekly blood glucose measurement. Serum and retinal tissue-based advanced glycation endproducts (AGE) levels significantly elevated in diabetic rats, and RBC was evaluated by transmission electron microscopy and Raman spectroscopy. The results showed that whole Raman spectra and all marked band intensities could respectively achieve almost equal and accurate discrimination of all animal groups, along with the determination of important molecules from the band data. Further quantitative analyses indicated series of metabolic disturbance due to hyperglycemia were involved while the body self-regulation mechanism still played a role with different effects during the disease progression. Given this, Raman spectroscopy can reliably distinguish the early characterization of DR in addition to providing intrinsic key molecules that is sensitive to identify the early disease progression.

Epigenomic, Transcriptomic, and Protective Effect of Carotenoid Fucoxanthin in High Glucose-Induced Oxidative Stress in Mes13 Kidney Mesangial Cells

Diabetic nephropathy (DN) is the major cause of kidney related diseases in patients induced by high glucose (HG) affecting around 40% of type 1 and 2 diabetic patients. It is characterized by excessive inflammation inducing factors, reactive oxygen species (ROS) overproduction, and potential epigenomic related changes. Fucoxanthin (FX), a carotenoid found in brown seaweed, has a structure which includes an allenic bond and a 5,6-monoepoxide in the molecule, with strong antioxidant and anti-inflammatory activity. However, understanding of the impact of FX on DN was lacking. In this study we tested the early effects of high glucose (HG) on mouse mesangial kidney Mes13 cells, a potential in vitro cell culture model of DN. Our results show that HG induced oxidative stress on kidney mesangial Mes13 cells, while FX treatment attenuates the oxidative stress by decreasing the ROS, demonstrated by flow cytometry. Next, we utilized next-generation sequencing (NGS) to profile the HG-induced early epigenomic and transcriptomic changes in this in vitro DN model and the protective effects of FX. Differentially expressed genes (DEGs) and differentially methylated regions (DMRs) were analyzed using R software in HG and FX treated groups. Differential regulation of signaling pathways was studied using Reactome Pathway Analysis in the comparison. DEG analysis shows that novel biomarkers with specific pathways, including interleukin regulation, Toll-like receptor pathway, and PKA phosphorylation pathways, were found to be modulated by the FX treatment. TGF β 1i1 (TGFB 1i1), MAP-3-kinase-13(MAP3K13) involved in crucial cellular processes including glucose metabolism, phosphodiesterase regulation was methylated in HG, which was demethylated with FX treatment. Integrated transcriptomic and CpG methylome analysis of DEGs and DMRs revealed that genes like adenylate cyclase (Adcy7), calponin 1 (CNN1), potassium voltage-gated channel interacting protein 2 (KCNIP2), phosphatidylinositol-4-phosphate 5-kinase type 1 β (PIP5K1B), and transmembrane protein with EGF-like and two follistatin-like domains 1 (TMEFF1), which were modulated by FX in HG-exposed Mes13 cells, potentially modulate ion channel transport and glucose metabolism. In summary, our current study shows that novel early epigenomic and transcriptomic biomarkers were altered during the disease progression of HG-induced DN and that FX modified these alterations potentially contributing to the protective effects of mesangial cells from the HG-induced oxidative stress and damage.

Studies on the Mechanism of Gegen Qinlian Decoction in Treating Diabetes Mellitus Based on Network Pharmacology

Diabetes mellitus (DM) is a chronic disease that is very common and seriously threatens patient health. Gegen Qinlian decoction (GQD) has long been applied clinically, but its mechanism in pharmacology has not been extensively and systematically studied. A GQD protein interaction network and diabetes protein interaction network were constructed based on the methods of system biology. Functional module analysis, Kyoto Encyclopedia of Genes and Genomes pathway analysis, and Gene Ontology (GO) enrichment analysis were carried out on the 2 networks. The hub nodes were filtered by comparative analysis. The topological parameters, interactions, and biological functions of the 2 networks were analyzed in multiple ways. By applying GEO-based external datasets to verify the results of our analysis that the Gene Set Enrichment Analysis (GSEA) displayed metabolic pathways in which hub genes played roles in regulating different expression states. Molecular docking is used to verify the effective components that can be combined with hub nodes. By comparing the 2 networks, 24 hub targets were filtered. There were 7 complex relationships between the networks. The results showed 4 topological parameters of the 24 selected hub targets that were much higher than the median values, suggesting that these hub targets show specific involvement in the network. The hub genes were verified in the GEO database, and these genes were closely related to the biological processes involved in glucose metabolism. Molecular docking results showed that 5,7,2', 6'-tetrahydroxyflavone, magnograndiolide, gancaonin I, isoglycyrol, gancaonin A, worenine, and glyzaglabrin produced the strongest binding effect with 10 hub nodes. This compound–target mode of interaction may be the main mechanism of action of GQD. This study reflected the synergistic characteristics of multiple targets and multiple pathways of traditional Chinese medicine and discussed the mechanism of GQD in the treatment of DM at the molecular pharmacological level.

Indian Traditional medicinal plants as a source of potent Anti-diabetic agents: A Review

Objective

The present review aims to provide an overview of traditional medicinal plants known to be of anti-diabetic potential.

Methods

A literature search was conducted using the scientific databases including PubMed, EMBASE and google scholar and a total of fifty herbs have been described and their possible mechanism of anti-diabetic action has been mentioned. Among them, in-depth discussion on five most potent anti-diabetic herbs has been provided with respect to their mechanism of action, in-vivo studies and clinical efficacies.

Results

The present review has highlighted the usefulness of the herbal source for the treatment and management of diabetes mellitus. With the help of previous literature published on In-vivo animal studies and human clinical studies; the effectiveness of Gymnema sylvestre, Momordica charantia, Trigonella foenum graecum, Tinospora cordifolia and Curcuma longa in the treatment and management of Diabetes has been proved.

Conclusion

Based on this review it can be concluded that herbs can serve as more efficient, safer, and cost-effective adjuvant therapy in the management and treatment of diabetes. Further investigations mainly focusing on the isolation of phytocompounds from these herbs can lead to the discovery of newer antidiabetic agents.

Resveratrol: Evidence for Its Nephroprotective Effect in Diabetic Nephropathy

Diabetic nephropathy (DN) is a severe complication of diabetes mellitus (DM). Dietary habits play a major role in determining the onset and progression of DM-related disorders and a proper diet (rich in fruits and vegetables) can delay or prevent the process of DM pathogenesis. Thus, increasing attention has been paid to polyphenols and polyphenol-rich foods since their increased intake has been associated with a reduced incidence of DM and its associated complications. Resveratrol is a polyphenolic phytoalexin that is mainly found in grapevines and berries. It is available in various pharmaceutical dosages and is widely recommended as a dietary supplement due to its beneficial effects. Remarkably, resveratrol's capability to effectively lower blood glucose levels without any side effects has been amply demonstrated in many in vitro and in vivo studies. Herein, we comprehensively review and discuss the nephroprotective effect of resveratrol during DN and its associated mechanisms. Resveratrol exerts its nephroprotective effects via various mechanisms including reducing oxidative stress and advanced glycation end-product (AGE) production, stimulating autophagy, inhibiting endoplasmic reticulum (ER) stress and inflammation, ameliorating lipotoxicity, activating the AMP kinase (AMPK) pathway, and modulating angiogenesis. Moreover, the use of resveratrol as an adjuvant to conventional antidiabetic therapies could be an effective approach to manage DN in humans. However, evidence is scarce to support whether resveratrol has beneficial effects in humans during DN. Therefore, clinical studies are warranted to elucidate resveratrol's role against DN.

Mechanisms of Herbal Nephroprotection in diabetes mellitus

Diabetic nephropathy (DN) is a leading cause of kidney morbidity. Despite the multilayered complexity of the mechanisms involved in the pathogenesis of DN, the conventional treatment is limited to just a few drug classes fraught with the risk of adverse events, including the progression of renal dysfunction. Phytoceuticals offer a promising alternative as they act on the many-sidedness of DN pathophysiology, multitargeting its intricacies. This paper offers a review of the mechanisms underlying the protective action of these phytoagents, including boosting the antioxidant capabilities, suppression of inflammation, averting the proliferative and sclerosing/fibrosing events. The pathogenesis of DN is viewed as a continuum going from the original offense, high glucose, through the noxious products it generates (advanced glycation end-products, products of oxidative and nitrosative stress) and the signaling chains consequently brought into action, to the harmful mediators of inflammation, sclerosis, and proliferation that eventually lead to DN, despite the countervailing attempts of the protective mechanisms. Special attention was given to the various pathways involved, pointing out the ability of the phytoagents to hinder the deleterious ones (especially those leading to, driven by, or associated with TGF-β activation, SREBP, Smad, MAPK, PKC, NF-κB, NLRP3 inflammasome, and caspase), to promote the protective ones (PPAR-α, PPAR-γ, EP4/Gs/AC/cAMP, Nrf2, AMPK, and SIRT1), and to favorably modulate those with potentially dual effect (PI3K/Akt). Many phytomedicines have emerged as potentially useful out of in vitro and in vivo studies, but the scarcity of human trials seriously undermines their usage in the current clinical practice-an issue that stringently needs to be addressed.

Zafirlukast, a Cysteinyl Leukotriene Receptor 1 Antagonist, Reduces the Effect of Advanced Glycation End-Products in Rat Renal Mesangial Cells In Vitro

Background

Zafirlukast is an antagonist of cysteinyl leukotriene receptor 1 (CysLTR1). Advanced glycation end-products (AGEs) are formed by the glycation of lipids and proteins in hyperglycemia, including diabetes mellitus. Zafirlukast has not previously been studied in diabetic nephropathy. This study aimed to investigate the effects of zafirlukast on rat renal mesangial cells cultured with AGEs in vitro.

Material/Methods

Mesangial cells were cultured in AGEs (0, 20, 50, 100 μg/ml), and with AGEs (100 μg/ml) and zafirlukast (2.5 μm, 5 μm, and 100 μm). An enzyme-linked immunoassay (ELISA) was used to measure the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, and monocyte chemoattractant protein-1 (MCP-1). Reactive oxygen species (ROS) were assessed by intracellular fluorescence measurement of 2′-7′-dichlorodihydrofluorescein diacetate (DCFH-DA), and detection kits were used to measure malondialdehyde (MDA), lactate dehydrogenase (LDH), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD). Cell apoptosis was assessed by flow cytometry, and Western blot was used to measure protein levels.

Results

In mesangial cells cultured with AGEs, markers of inflammation, oxidative stress, and apoptosis and levels of CysLTR1 increased, and these effects were reduced by zafirlukast in a dose-dependent manner. The effects of zafirlukast as a CysLTR1 antagonist protected mesangial cells from the effects of AGE in vitro.

Conclusions

Zafirlukast, a CysLTR1 antagonist, reduced the levels of inflammatory cytokines, markers of oxidative stress, and cell apoptosis induced by AGE in mesangial cells in a dose-dependent way. Future in vivo studies are needed to investigate the potential role for zafirlukast in models of diabetic nephropathy.

Coriandrum sativum seeds extract mitigate progression of diabetic nephropathy in experimental rats via AGEs inhibition

Inthe present study, we have demonstrated the phytochemical composition of petroleum ether extract of C. sativum (CPE) seeds by using chromatographic, spectroscopic as well spectrometric analysis. CPE was evaluated for its possible role in mitigation of diabetic nephropathy (DN) in Streptozotocin (STZ)-nicotinamide (NAD) induced type 2 diabetes model. Administration of CPE at doses of 100, 200, and 400 mg/kg for 45 days has produced significant attenuation of elevated biochemical parameters including serum glucose, lipid and creatinine levels. CPE has also reserved albuminuria and elevated creatinine clearance in treated diabetic rats. Advanced glycation end products (AGEs) formation in kidneyswas also considerably reduced along with noteworthy increase in level of superoxide dismutase (SOD), glutathione (GSH), and decrease in lipid peroxidation in terms of thiobarbituric acid reactive species (TBARS). Molecular docking studies were also employed to reveal out the possible mechanism. In conclusion, using STZ-NAD model, we have successfully predicted that by assets of bioactive constituents CPE might inhibit the progression of DN. C. sativum may act as potential adjuvant for antidiabetic therapy and needs to be investigated further.

Notoginsenoside R1 Protects db/db Mice against Diabetic Nephropathy via Upregulation of Nrf2-Mediated HO-1 Expression

Diabetic nephropathy (DN) is a leading cause of end-stage renal failure, and no effective treatment is available. Notoginsenoside R1 (NGR1) is a novel saponin that is derived from Panax notoginseng, and our previous studies showed the cardioprotective and neuroprotective effects of NGR1. However, its role in protecting against DN remains unexplored. Herein, we established an experimental model in db/db mice and HK-2 cells exposed to advanced glycation end products (AGEs). The in vivo investigation showed that NGR1 treatment increased serum lipid, β2-microglobulin, serum creatinine, and blood urea nitrogen levels of db/db mice. NGR1 attenuated histological abnormalities of kidney, as evidenced by reducing the glomerular volume and fibrosis in diabetic kidneys. In vitro, NGR1 treatment was further found to decrease AGE-induced mitochondria injury, limit an increase in reactive oxygen species (ROS), and reduce apoptosis in HK-2 cells. Mechanistically, NGR1 promoted nucleus nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) expressions to eliminate ROS that induced apoptosis and transforming growth factor beta (TGF-β) signaling. In summary, these observations demonstrate that NGR1 exerts renoprotective effects against DN through the inhibition of apoptosis and renal fibrosis caused by oxidative stress. NGR1 might be a potential therapeutic medicine for the treatment of DN.

Ameliorative effect of Cephalandra indica homeopathic preparation in STZ induced diabetic nephropathy rats

Background

Diabetic nephropathy (DN) is the foremost cause of morbidity and has become the most recurrent cause of end-stage renal disease among diabetic patients. Thus, agents having antidiabetic effect along with safety potential in the kidneys would have a higher remedial value.

Objective

The present study aimed to investigate possible protective effect of homeopathic preparation of Cephalandra indica Mother tincture, 6C and 30 C potencies on DN in Wistar rats.

Materials and methods

DN was induced by intraperitoneal injection of STZ (60 mg/kg) 15 min after Nicotinamide (230 mg/kg, i.p.) administration. Rats were divided into six groups (n = 6). Group 1 and 2 was kept normal control and diabetic control respectively whereas Groups 3–5 consist of diabetic nephropathy rats treated with different doses of C. indica Mother tincture, 6C and 30 C potencies for 45 days. Glimepride (10 mg/kg) was used as standard. DN was assessed by determining serum glucose, urea, uric acid, creatinine level and tissue histological examination. Tissue antioxidant enzymes (SOD, GSH, LPO) level was measured to assess the oxidative stress. Also, the level of advanced glycation end products in kidney was determined.

Results

Mother tincture, 6C and 30 C potencies of C. indica produced significant attenuation in the biochemical parameters used to assess diabetic nephropathy. Moreover, oxidative stress and AGE's level in kidney was also found to be significantly reduced.

Conclusion

We conclude that Mother tincture, 6C and 30 C potencies of C. indica confers protective effect against diabetic nephropathy via inhibition of Oxidative stress and AGE's.

An allied approach for in vitro modulation of aldose reductase, sorbitol accumulation and advanced glycation end products by flavonoid rich extract of Coriandrum sativum L. seeds

Traditional herbal medicines are attaining more popularity and are being widely practiced. Coriandrum sativum L. is one of the oldest herbal medicinal plants valued for its nutritional and medicinal properties. Present investigation was focussed on evaluation of attenuating potential of flavonoid rich extract of C. sativum (FCS) seeds against pathogenic markers of diabetic complications i.e. advanced glycation end products (AGEs), sorbitol and aldose reductase (ALR); by using in-vitro methods. Gas chromatography-mass spectrometry (GC-MS) and Infrared spectroscopy of FCS revealed the presence of different flavonoids. Results demonstrated that FCS has produced 79.80% inhibition of AGEs formation. Additionally, FCS was effective against sorbitol accumulation and ALR inhibition with IC₅₀ values of 221 μg/ml and 6.08 μg/ml respectively. Molecular docking was conducted against three binding site for ALR, RAGEs and sorbitol dehydrogenase to explore their binding interactions with identified flavonoids. The constituents F₂, F₄ and F₆ have shown good binding interactions with all the receptors. The visualisation of the docked complexes revealed the occurrence of hydrophobic forces and hydrogen bonding in receptor and docked constituents. The results were in support with experimental inhibitory activities of FCS against these biomarkers and provide a considerable basis for the identification and development of new inhibitors.

Advances in early biomarkers of diabetic nephropathy

Diabetic nephropathy is the main cause of chronic kidney disease, and represents the most common and serious complication of diabetes. The exact pathogenesis is complex and not elucidated. Several factors and mechanisms contribute to the development and outcome of diabetic nephropathy. An early diagnosis and intervention may slow down disease progression. A variety of biological markers associated with diabetic nephropathy were found in recent years, which was important for predicting the occurrence and development of the disease. Therefore, this article provides an overview of early biomarkers that are associated with diabetic nephropathy.

Effect of Kaempferol isolated from seeds of Eruca sativa on changes of pain sensitivity in Streptozotocin-induced diabetic neuropathy

Generation of excessive reactive oxygen species (ROS) and advanced glycation end products (AGEs), and cellular apoptosis are implicated in the pathogenesis of diabetic neuropathy. Present study was aimed to explore the effect of Eruca sativa and Kaempferol (KP) on hyperalgesia (thermal and mechanical); tactile allodynia, motor nerve conduction velocity (MNCV) and oxidative-nitrosative stress in streptozotocin (STZ) induced experimental diabetes. Neuropathy developed in diabetic rats was evident from a marked hyperalgesia and allodynia; reduced MNCV associated with excess formation of AGEs and ROS. Chronic treatment with E. sativa hydroalcoholic extract (EHA; 100, 200 and 400 mg/kg) and KP (5 and 10 mg/kg) for 30 days starting from the 60th day of STZ administration significantly ameliorated behavioral and biochemical changes linked to diabetic neuropathy. Present study suggested that EHA and KP corrected hyperglycemia and reversed the pain response partially in diabetic rats along via modulating oxidative and nitrosative stress along with reduction of AGEs formation in diabetic rats. Thus E. sativa might be beneficial in chronic diabetes, ameliorate the progression of diabetic neuropathy and may also find application in diabetic neuropathic pain.

Curcumin suppresses AGEs induced apoptosis in tubular epithelial cells via protective autophagy

Renal tubular cell apoptosis and tubular dysfunction is an important process underlying diabetic nephropathy (DN). Understanding the mechanisms underlying renal tubular epithelial cell survival is important for the prevention of kidney damage associated with glucotoxicity. Curcumin has been demonstrated to possess potent anti-apoptotic properties. However, the roles of curcumin in renal epithelial cells are yet to be defined. The present study investigated advanced glycation or glycoxidation end-product (AGE)-induced toxicity in renal tubular epithelial cells via several complementary assays, including cell viability, cell apoptosis and cell autophagy in the NRK-52E rat kidney tubular epithelial cell line. The extent of apoptosis was significantly increased in the NRK-52E cells following treatment with AGEs. The results also indicated that curcumin reversed this effect by promoting autophagy through the phosphoinositide 3-kinase/AKT serine/threonine kinase signaling pathway. These conclusions suggested that curcumin exerts a renoprotective effect in the presence of AGEs, at least in part by activating autophagy in NRK-52E cells. Collectively, these findings indicate that curcumin not only exerts renoprotective effects, however may also act as a novel therapeutic strategy for the treatment of diabetic nephropathy.

Activation of AMPK is neuroprotective in the oxidative stress by advanced glycosylation end products in human neural stem cells

Advanced glycosylation end products (AGEs) formation is correlated with the pathogenesis of diabetic neuronal damage, but its links with oxidative stress are still not well understood. Metformin, one of the most widely used anti-diabetic drugs, exerts its effects in part by activation of AMP-activated protein kinase (AMPK). Once activated, AMPK regulates many pathways central to metabolism and energy balance including, glucose uptake, glycolysis and fatty acid oxidation. AMPK is also present in neurons, but its role remains unclear. Here, we show that AGE exposure decreases cell viability of human neural stem cells (hNSCs), and that the AMPK agonist metformin reverses this effect, via AMPK-dependent downregulation of RAGE levels. Importantly, hNSCs co-treated with metformin were significantly rescued from AGE-induced oxidative stress, as reflected by the normalization in levels of reactive oxygen species. In addition, compared to AGE-treated hNSCs, metformin co-treatment significantly reversed the activity and mRNA transcript level changes of SOD1/2 and Gpx. Furthermore, hNSCs exposed to AGEs had significantly lower mRNA levels among other components of normal cellular oxidative defenses (GSH, Catalase and HO-1), which were all rescued by co-treatment with metformin. This metformin-mediated protective effect on hNSCs for of both oxidative stress and oxidative defense genes by co-treatment with metformin was blocked by the addition of an AMPK antagonist (Compound C). These findings unveil the protective role of AMPK-dependent metformin signaling during AGE mediated oxidative stress in hNSCs, and suggests patients undergoing AGE-mediated neurodegeneration may benefit from the novel therapeutic use of metformin.

Chromane isolated from leaves of Dillenia indica improves the neuronal dysfunction in STZ-induced diabetic neuropathy

ETHNOPHARMACOLOGICAL RELEVANCE

According to the Indian traditional medicine, Dillenia indica L. has shown therapeutic efficacy in various diseases. Fruits and leaves of the plant possess anti-oxidant and anti-inflammatory properties. Reactive oxygen species, formation of advanced glycation end products (AGEs) and apoptosis are implicated in the pathogenesis of diabetic neuropathy.

AIM OF THE STUDY

The aim of the present study was to explore the effect of D. indica and its isolate, chromane (CR), on thermal and mechanical hyperalgesia, allodynia, MNCV and oxidative-nitrosative stress in streptozotocin-induced experimental diabetes.

MATERIAL AND METHODS

Diabetes was induced by intraperitoneal administration of Streptozotocin (STZ; 65mg/kg) for the development of diabetic neuropathy. Chronic treatment with DAE (100, 200 and 400mg/kg, p.o.) and CR (5 and 10mg/kg, p.o.) for 30 days was started from the 60th day of STZ administration. Development of neuropathy was evident from a marked hyperalgesia and allodynia; reduced MNCV associated with increased formation of AGEs and reactive oxygen species.

RESULTS

significantly attenuated behavioral and biochemical changes associated with diabetic neuropathy. Present study suggested that DAE and CR ameliorated hyperglycemia and diabetic neuropathic pain via modulation of oxidative-nitrosative stress and reduction in AGEs formation in the diabetic rats.

CONCLUSION

Thus D. indica might be beneficial in chronic diabetics, ameliorate the progression of diabetic neuropathy and may also find application in diabetic neuropathic pain.

Dillenia indica L. attenuates diabetic nephropathy via inhibition of advanced glycation end products accumulation in STZ-nicotinamide induced diabetic rats

The present study was aimed to evaluate advanced glycation end products (AGEs) inhibitory activity of alcohol and hydro-alcohol extract (DAE and DHE) of Dillenia indica L. (Family: Dilleniaceae) and its potential in treatment of diabetic nephropathy by targeting markers of oxidative stress. D. indica was evaluated for its in vitro inhibitory activity against formation of AGEs by using bovine serum albumin. Diabetes was induced in male Wistar rats by streptozotocin (65 mg/kg i.p.) 15 min after nicotinamide (230 mg/kg, i.p.) administration. Diabetic rats were treated with different doses of extracts (100, 200 and 400 mg/kg) to analyze their nephroprotective effect. Tissue antioxidant enzymes level was measured along with the formation of AGEs in kidney to assess the effect of D. indica in ameliorating oxidative stress. D. indica showed significant inhibition of AGEs formation in vitro. D. indica produced significant attenuation in the glycemic status, renal parameter, lipid profile and level of antioxidant enzymes proving efficacy in diabetic nephropathy. Moreover, D. indica produced significant reduction in the formation of AGEs in kidneys. The present study concludes that D. indica as a possible therapeutic agent against diabetic nephropathy.

Role of Nuclear Factor Erythroid 2-Related Factor 2 in Diabetic Nephropathy

Diabetic nephropathy (DN) is manifested as increased urinary protein level, decreased glomerular filtration rate, and final renal dysfunction. DN is the leading cause of end-stage renal disease worldwide and causes a huge societal healthcare burden. Since satisfied treatments are still limited, exploring new strategies for the treatment of this disease is urgently needed. Oxidative stress takes part in the initiation and development of DN. In addition, nuclear factor erythroid 2-related factor 2 (Nrf2) plays a key role in the cellular response to oxidative stress. Thus, activation of Nrf2 seems to be a new choice for the treatment of DN. In current review, we discussed and summarized the therapeutic effects of Nrf2 activation on DN from both basic and clinical studies.