Potential of Renin-Angiotensin-Aldosterone System Modulations in Diabetic Kidney Disease: Old Players to New Hope!

Due to a tragic increase in the incidences of diabetes globally, diabetic kidney disease (DKD) has emerged as one of the leading causes of end-stage renal diseases (ESRD). Hyperglycaemia-mediated overactivation of the renin-angiotensin-aldosterone system (RAAS) is key to the development and progression of DKD. Consequently, RAAS inhibition by angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARBs) is the first-line therapy for the clinical management of DKD. However, numerous clinical and preclinical evidences suggested that RAAS inhibition can only halt the progression of the DKD to a certain extent, and they are inadequate to cure DKD completely. Recent studies have improved understanding of the complexity of the RAAS. It consists of two counter-regulatory arms, the deleterious pressor arm (ACE/angiotensin II/AT1 receptor axis) and the beneficial depressor arm (ACE2/angiotensin-(1-7)/Mas receptor axis). These advances have paved the way for the development of new therapies targeting the RAAS for better treatment of DKD. In this review, we aimed to summarise the involvement of the depressor arm of the RAAS in DKD. Moreover, in modern drug discovery and development, an advance approach is the bispecific therapeutics, targeting two independent signalling pathways. Here, we discuss available reports of these bispecific drugs involving the RAAS as well as propose potential treatments based on neurohormonal balance as credible therapeutic strategies for DKD.

Pharmacokinetics, pharmacodynamics, toxicity, and formulations of daidzein: An important isoflavone.

Daidzein, 7-hydroxy-3-(4-hydroxyphenyl)-4H-chromen-4-one is a naturally occurring compound present in leguminous plants, especially in soybeans. Chemically it belongs to the isoflavone class and possesses high nutritive value. Daidzein acts on estrogen receptor and is non-steroidal in nature hence it can also be called as non-steroidal phytoestrogenic compound. Daidzein has been studied by many researchers for its pharmacological activities. Daidzein metabolites were also studied in detail for their health benefits. Researchers have developed novel formulations of daidzein in the past few years to improve its aqueous solubility and bioavailability. Self-emulsified daidzein, poly(lactic-co-glycolic) acid daidzein nanoparticles, nanoemulsion, nanoemulsion gel, and co-crystals are a few of them. The present review provides detailed information on the chemistry, drug development aspects, pharmacokinetics, and pharmacodynamics of daidzein. A literature search was performed using various datasets like PubMed, EBSCO, ProQuest Scopus, and selected websites including the National Institutes of Health and the World Health Organization. Daidzein has a wide range of pharmacodynamic properties in the treatment of cancer, neurodegenerative disorders, cardiac disorders, diabetes and its complication, osteoporosis, and skin disorders. The pharmacokinetic, pharmacodynamics, and drug development aspects of daidzein will help researchers to design further research work on daidzein in the future.

Effects of Acute and Repeated Dose Toxicity Profiling of Chelidonic Acid in Rats: in Silico and in Vivo Evidence.

Chelidonic acid is a phytoconstituent found in rhizomes of the perennial plant celandine. The current study aims to evaluate the acute and repeated dose oral toxicity study of chelidonic acid as per the OECD guidelines 425 and 407. The pharmacokinetic and toxicity profile of chelidonic acid was predicted using online servers and tools. A single dose of chelidonic acid (2000 mg/kg) was administered to female Wistar rats in an acute toxicity study, and the animals were monitored for 14 days. We studied the toxicity profile of chelidonic acid at 10, 20, and 40 mg/kg doses in Wistar rats for repeated dose toxicity (28 days). Clinical biochemistry, haematological, and urine parameters were estimated. A gross necropsy and histopathology were performed. A single oral dose of chelidonic acid (2000 mg/kg) showed no signs of toxicity or mortality. The Administration of chelidonic acid showed no significant alterations in haematological, biochemical, and urine parameters. The histopathology showed normal structure and architecture in all the vital organs. A gross necropsy of vital organs showed no signs of toxicity. The chelidonic acid was found to be safe at all selected dose levels in the acute and repeated dose toxicity study in rats.

Neuroprotective Effect of Quercetin and Memantine against AlCl3-Induced Neurotoxicity in Albino Wistar Rats.

Recent evidences indicate that there is a substantial increase in worldwide cases of dementia. Alzheimer's disease is the leading cause of dementia and may contribute to 60-70% of cases. Quercetin is a unique bioflavonoid that has numerous therapeutic benefits such as anti-allergy, anti-ulcer, anti-inflammatory, anti-hypertensive, anti-cancer, immuno-modulatory, anti-infective, antioxidant, acetylcholinesterase inhibitory activity, neuroprotective effects, etc. In the present study, we evaluated the neuroprotective effect of orally administered quercetin with memantine in albino Wistar rats after inducing neurotoxicity through AlCl3 (100 mg/kg, p.o.). Chronic administration of AlCl3 resulted in poor retention of memory and significant oxidative damage. Various behavioral parameters, such as locomotor activity, Morris water maze, elevated plus maze, and passive avoidance test, were assessed on days 21 and 42 of the study. The animals were euthanatized following the completion of the last behavioral assessment. Various oxidative stress parameters were assessed to know the extent of oxidative damage to brain tissue. Quercetin with memantine has shown significant improvement in behavioral studies, inhibition of AChE activity, and reduction in oxidative stress parameters. Histopathological studies assessed for cortex and hippocampus using hematoxylin and eosin (H&E), and Congo red stain demonstrated a reduction in amyloid-ß plaque formation after treatment of quercetin with memantine. Immunohistochemistry showed that quercetin with memantine treatment also improved the expression of brain-derived neurotrophic factor (BDNF) and inhibited amyloid-ß plaque formation. The present study results demonstrated protective effects of treatment of quercetin with memantine in the neurotoxicity linked to aluminum chloride in albino Wistar rats.

SIRT1-FOXOs activity regulates diabetic complications.

The prevalence of diabetes is continuously increasing in the recent decades. Persistent hyperglycemia, hyperinsulinemia and the subsequent oxidative stress result in diabetic complications, primarily categorized as microvascular (nephropathy, retinopathy and neuropathy) and macrovascular (cardiomyopathy) complications. The complications are prevalent in both type 1 and type 2 diabetic patients. Polyol pathway, elevated AGE production, PKC activation and hexosamine pathway are indeed the critical pathways involved in the progression of diabetic complications. Silent information regulator 2 or SIR2 or more commonly known as sirtuins are NAD+ dependent histone deacetylase. SIRT1, a member of the sirtuin family has been extensively studied for its role in lifespan extension and needs to be explored for its beneficial effects in diabetic complications. Moreover, it is also known to regulate the activity of other proteins and transcription factors. One such substrate of SIRT1 is FOXOs transcription factor which has gained much attention as the mediator of various cellular processes such as cell cycle arrest and proliferation, DNA repair and metabolism. It has been reported that SIRT1 regulates the activity of FOXOs, whereas few recent advances also suggest a role FOXOs in governing the activity of SIRT1, which permits for a crosstalk between SIRT1 and FOXOs. Therefore, the focus of the present review is to describe and explore the interaction between SIRT1 and FOXOs, predominantly FOXO1 and FOXO3 and to understand the underlying mechanism of SIRT1-FOXOs in controlling and alleviating diabetic complications. Thus, this crosstalk suggests that SIRT1 and FOXOs may serve as potential therapeutic targets in treating diabetic complications.

Autophagy-nutrient sensing pathways in diabetic complications.

The incidence of diabetes has been increasing in recent decades which is affecting the population of both, developed and developing countries. Diabetes is associated with micro and macrovascular complications which predominantly result from hyperglycemia and disrupted metabolic pathways. Persistent hyperglycemia leads to increased reactive oxygen species (ROS) generation, formation of misfolded and abnormal proteins, and disruption of normal cellular functioning. The inability to maintain metabolic homeostasis under excessive energy and nutrient input, which induces insulin resistance, is a crucial feature during the transition from obesity to diabetes. According to various study reports, redox alterations, intracellular stress and chronic inflammation responses have all been linked to dysregulated energy metabolism and insulin resistance. Autophagy has been considered a cleansing mechanism to prevent these anomalies and restore cellular homeostasis. However, disrupted autophagy has been linked to the pathogenesis of metabolic disorders such as obesity and diabetes. Recent studies have reported that the regulation of autophagy has a beneficial role against these conditions. When there is plenty of food, nutrient-sensing pathways activate anabolism and storage, but the shortage of food activates homeostatic mechanisms like autophagy, which mobilises internal stockpiles. These nutrient-sensing pathways are well conserved in eukaryotes and are involved in the regulation of autophagy which includes SIRT1, mTOR and AMPK. The current review focuses on the role of SIRT1, mTOR and AMPK in regulating autophagy and suggests autophagy along with these nutrient-sensing pathways as potential therapeutic targets in reducing the progression of various diabetic complications.

Biochanin A Attenuates Cardiomyopathy in Type 2 Diabetic Rats by Increasing SIRT1 Expression and Reducing Oxidative Stress.

Diabetic cardiomyopathy is one of the major complications in type 2 diabetes associated with myocardial structure abnormality and major cause of morbidity in type 2 diabetic patients. Biochanin A is a methylated isoflavone present in flowering tops of Trifolium pratense reported for anti-inflammatory, anti-oxidant, anti-infective, anti-cancer and anti-diabetic activity. The study was designed to assess the efficacy of Biochanin A in type 2 diabetic cardiomyopathy. Type 2 diabetes was induced in rats feeding high fat diet for two weeks and administration of single low dose of streptozotocin. Biochanin A was administered for 16 weeks orally once in a day (10, 20 and 40 mg/kg of body weight). Various parameters such as blood glucose, cardiac markers, oxidative stress and hemodynamic parameters, immunohistochemical, histopathological investigation and SIRT1 expression were measured at the end of the study. Biochanin A treatment resulted into reduction in plasma concentration of cardiac markers along with reduction in hyperglycemia, hyperlipidemia and oxidative stress in cardiac tissue. Biochanin A treated animals also demonstrated improvement in hemodynamic parameters. Diabetic animals treated with different doses of Biochanin A shown increased SIRT1 expression in cardiac tissue, and also confirmed reduced cardiac hypertrophy and cardiac protection in histopathological study. Outcome of the study indicates that Biochanin A is the potential candidate to control hyperglycemia, oxidative stress and improve SIRT1 expression in cardiac tissue. Biochanin A might be considered as potential candidate to control progression of cardiomyopathy in type 2 diabetes mellitus.

Glycosides and Vascular Complications of Diabetes.

Diabetes is linked with various microvascular and macrovascular complications. Nephropathy, neuropathy and retinopathy are important microvascular complications of diabetes. Different types of secondary metabolites including glycosides have been studied for their effects in diabetic complications. Various glycosides such as flavanoid glycosides and saponin glycosides are reported for their beneficial effects in diabetic nephropathy, neuropathy, retinopathy and cardiomyopathy by action on various pathways involved in the progression of these complications. Coumarin glycosides and cryanogenic glycosides have been studied for their effective role in diabetic nephropathy. Phenolic glycosides and anthraquinone glycosides also have beneficial role in diabetic neuropathy. The present review focuses on various classes of glycosides and their role in the prevention and treatment of vascular complications of diabetes.

In-vivo and in-silico toxicity studies of daidzein: an isoflavone from soy.

Daidzein is a naturally occurring compound belonging to the class isoflavones and found in soya beans and other legumes. Acute oral toxicity was performed as per OECD guideline (TG 423) with slight modifications. A repeated dose toxicity study was carried out as per OECD guideline (TG 407). In-silico toxicity such as AMES toxicity, carcinogenicity, mutagenicity, immunotoxicity, hepatotoxicity, skin irritation, reproductive effect, rat and mouse toxicity, LD50, hERG I, II inhibitor and minnow toxicity were predicted using online servers and tools. In an acute oral toxicity study, daidzein did not show any mortality in experimental animals. The No Observed Adverse Effect Level (NOAEL) of daidzein was found to be above 5000 mg/kg. 28 days treatment of diadzein at all doses did not show changes in hematology parameters, clinical biochemistry and kidney function parameters. Gross necropsy or histopathology of important organs showed no signs of toxicity. In-silico predicted parameters also demonstrated risks ranging from low to a nontoxic level. Thus, daidzein was found to be safe in acute and repeated oral dose toxicity studies at all selected doses. In-silico study also indicated that daidzein is safe.

Pharmacology of apocynin: a natural acetophenone.

Apocynin is a naturally occurring acetophenone, found in the roots of Apocynum cannabinum and Picrorhiza kurroa. Various chemical and pharmaceutical modifications have been carried out to enhance the absorption and duration of action of apocynin, like, formulation of chitosan-based apocynin-loaded solid lipid nanoparticles, chitosan-oligosaccharide based nanoparticles, and biodegradable polyanhydride nanoparticles. Apocynin has been subjected to a wide range of experimental screening and has proved to be useful for amelioration of a variety of disorders, like diabetic complications, neurodegeneration, cardiovascular disorders, lung cancer, hepatocellular cancer, pancreatic cancer, and pheochromocytoma. Apocynin has been primarily reported as an NADPH oxidase (NOX) inhibitor and prevents translocation of its p47phox subunit to the plasma membrane, observed in neurodegeneration and hypertension. However, recent studies highlight its off-target effects that it is able to function as a scavenger of non-radical oxidant species, which is relevant for its activity against NOX 4 mediated production of hydrogen peroxide. Additionally, apocynin has shown inhibition of eNOS-dependent superoxide production in diabetic cardiomyopathy, reduction of NLRP3 activation and TGFß/Smad signaling in diabetic nephropathy, diminished VEGF expression and decreased retinal NF-κB activation in diabetic retinopathy, inhibition of P38/MAPK/Caspase3 pathway in pheochromocytoma, inhibition of AKT-GSK3ß and ERK1/2 pathways in pancreatic cancer, and decreased FAK/PI3K/Akt signaling in hepatocellular cancer. This review aims to discuss the pharmacokinetics and mechanisms of the pharmacological actions of apocynin.

Role of dietary modifications in the management of type 2 diabetic complications.

Diabetes is a chronic metabolic disorder with a high rate of morbidity and mortality. Insufficient insulin secretion and insulin action are two major causes for the development of diabetes, which is characterized by a persistent increase in blood glucose level. Diet and sedentary life style play pivotal role in development of vascular complications in type 2 diabetes. Dietary modification is associated with a reprogramming of nutrient intake, which are proven to be effective for the management of diabetes and associated complications. Dietary modifications modulate various molecular key players linked with the functions of nutrient signalling, regulation of autophagy, and energy metabolism. It activates silent mating type information regulation 2 homolog1 (SIRT1) and AMP-activated protein kinase (AMPK). AMPK mainly acts as an energy sensor and inhibits autophagy repressor Mammalian target of rapamycin (mTOR) under nutritional deprivation. Under calorie restriction (CR), SIRT1 gets activated directly or indirectly and plays a central role in autophagy via the regulation of protein acetylation. Dietary modification is also effective in controlling inflammation and apoptosis by decreasing the level of pro-inflammatory cytokines like nuclear factor kappa- beta (NF-kß), tissue growth factor-beta (TGF-ß), tissue necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6). It also improves glucose homeostasis and insulin secretion through beta cell regeneration. This indicates calorie intake plays a crucial role in the pathogenesis of type 2 diabetes-associated complications. The present review, emphasizes the role of dietary modifications in diabetes and associated complications.

Attenuation of Cardiac Autonomic Neuropathy by Escin in Diabetic Rats.

Cardiac autonomic neuropathy (CAN) is a least diagnosed complication of diabetes. Inflammation and oxidative stress play a crucial role in the pathophysiology of cardiomyopathy and neuropathy. Escin has anti-inflammatory activity and antioxidant activity. Hence, the present study was designed to evaluate the effect of escin in the management of CAN. Diabetes was induced in Sprague Dawley rats with streptozotocin (STZ). Diabetic animals were randomized in different groups after 6 weeks. Animals in the diabetic control group received no treatment, while animals in other groups received escin at dose 5, 10, and 20 mg/kg for 4 weeks. One group was kept as normal control. Various parameters like basic hemodynamic parameters, heart rate variability (HRV), oxidative stress parameters, and matrix metalloproteinase 9 (MMP-9) were assessed at the end of study. Escin significantly normalized hemodynamic parameters and HRV as compared to diabetic animals. Escin significantly reduced the malondialdehyde level and significantly increased reduced glutathione, catalase and superoxide dismutase levels in diabetic animals. Escin treatment significantly reduced plasma MMP-9 level in diabetic rats. The improvement in the studied parameters was found mainly with administration of higher doses of escin (10 and 20 mg/kg). The escin treatment mitigates CAN in diabetic rats. The results of study indicate that escin can be useful option for management of CAN.

Triphala Ameliorates Nephropathy via Inhibition of TGF-ß1 and Oxidative Stress in Diabetic Rats.

INTRODUCTION: Advanced glycation end products, oxidative stress, and TGF-ß expression play a crucial role in pathophysiology of diabetic nephropathy. Inhibition of oxidative stress and TGF-ß expression by natural traditional medicines may give an economic and safe alternative treatment option. Triphala churna, a traditional medicine, has been proved to have potent antioxidant activity, and individual components of it have shown significant antidiabetic activity. Hence, the present study was designed to study the effect of Triphala churna in diabetic nephropathy in rats. METHODS: Diabetes was induced in rats by administration of streptozotocin (55 mg/kg i.p.). Four weeks after induction of diabetes, the animals were treated with Triphala churna at the doses of 250, 500, and 1,000 mg/kg for next 4 weeks. Various biochemical and urine parameters such as glucose, creatinine, blood urea nitrogen (BUN), total protein, and albumin were assessed at the end of study. Creatinine clearance, BUN clearance, and glomerular filtration rate were determined. Oxidative stress parameters such as malondialdehyde, catalase, reduced glutathione, and superoxide dismutase were determined in kidney tissues. TGF-ß1 expression was measured with ELISA, immunohistochemistry, and western blot techniques. Histopathology study was carried out with haemotoxylin and eosin, periodic acid-Schiff, and Masson's trichrome staining to determine histological changes. RESULTS: Treatment with Triphala churna significantly improved urine parameters. Triphala churna treatment also improved plasma proteins, albumin, creatinine, and BUN levels. The oxidative stress was reduced in the kidney with the treatment of Triphala churna. Histopathological studies revealed that Triphala churna reduced kidney damage. Immunohistochemistry, ELISA, and western blotting study revealed that treatment with Triphala decreased the expression of TGF-ß in kidney tissues. CONCLUSION: From the results, it can be concluded that Triphala churna has a significant nephroprotective effect because of its capability of inhibiting oxidative stress and TGF-ß in diabetes.

Trifolium pratense (Red Clover) Improve SIRT1 Expression and Glycogen Content in High Fat Diet-Streptozotocin Induced Type 2 Diabetes in Rats.

Flowering tops of Trifolium pratense L. (Fabaceae) are known for its traditional medicinal values. In present study, our aim was to investigate effect of standardized aqueous extract of flowering tops of Trifolium pratense L. on insulin resistance and SIRT1 expression in type 2 diabetic rats. Type 2 diabetes was induced by feeding high fat diet and administering low dose of streptozotocin. Diabetic animals were treated with standardized aqueous extract at three different doses. Parameters such as blood glucose, lipid profile, glycohemoglobin, insulin sensitivity, HOMA-IR and liver glycogen content were measured. Changes in morphology and expression of SIRT1 in pancreatic tissue were measured in histopathological and immunohistological studies. Aqueous extract treatment showed reduction in hyperglycemia and improved insulin sensitivity. Extract treatment also showed reduction in formation of glycated hemoglobin and improved liver glycogen level. Histopathological study revealed protecting effect of extract in pancreatic tissue against hyperglycemia induced damage. Treatment increased expression of SIRT1 in rat pancreatic tissue. Results indicate that the aqueous extract of Trifolium pratense had beneficial role in improving insulin sensitivity and SIRT1 expression.

Formononetin Ameliorates Diabetic Neuropathy by Increasing Expression of SIRT1 and NGF.

Diabetic neuropathy is commonly observed complication in more than 50 % of type 2 diabetic patients. Histone deacetylases including SIRT1 have significant role to protect neuron from hyperglycemia induced damage. Formononetin (FMNT) is known for its effect to control hyperglycemia and also activate SIRT1. In present study, we evaluated effect of FMNT as SIRT1 activator in type 2 diabetic neuropathy. Type 2 diabetic neuropathy was induced in rats by modification of diet for 15 days using high fat diet and administration of streptozotocin (35 mg/kg/day, i. p.). FMNT treatment was initiated after confirmation of type 2 diabetes. Treatment was given for 16 weeks at 10, 20 and 40 mg/kg/day dose orally. FMNT treatment-controlled hypoglycemia and reduced insulin resistance significantly in diabetic animals. FMNT treatment reduced oxidative stress in sciatic nerve tissue. FMNT treatment also reduced thermal hyperalgesia and mechanical allodynia significantly. It improved conduction velocity in nerve and unregulated SIRT1 and NGF expression in sciatic nerve tissue. Results of present study indicate that continuous administration of FMNT protected diabetic animals from hyperglycemia induced neuronal damage by controlling hyperglycemia and increasing SIRT1 and NGF expression in nerve tissue. Thus, FMNT can be an effective candidate for treatment of type 2 diabetic neuropathy.

In Silico and In Vivo Toxicological Evaluation of Paeonol.

Paeonol is a phenolic compound reported for its various pharmacological activities such as antioxidant, anti-inflammatory and antidiabetic activity. There are no systematic scientific reports on the in vivo toxicity of paeonol. So, the present work was designed to study in silico and in vivo toxicity of paeonol. In silico toxicity predictions were carried out using pkCSM, ProTox-II, pre-ADMET server and OSIRIS property explorer. Acute oral toxicity study of paeonol was carried out in female Sprague Dawley rats at a single dose of 300 mg/kg, 2000 mg/kg and 5000 mg/kg. Animals were observed for toxicity signs and mortality for 14 days. Repeated dose oral toxicity study of paeonol was carried out in female and male Sprague Dawley rats at a dose of 50, 100 and 200 mg/kg body weight for 28 days. At the end of the study, hematological, biochemical and urine parameters were assessed. Histopathology of vital organs was also carried out. In silico toxicity study predicted that paeonol is non-toxic. The maximally tolerated dose of paeonol was found to be 5000 mg/kg in acute toxicity study in female rats. Paeonol was found to be safe at a dose of 50, 100 and 200 mg/kg in repeated dose toxicity study in male and female rats.

Development and Validation of HPLC Method for Determination of Sodium Copper Chlorophyllin - A Food Colorant and Its Application in Pharmacokinetic Study.

A simple, accurate, and precise bioanalytical method was developed and validated for the determination of pharmacokinetic parameters of sodium copper chlorophyllin, a USFDA approved food additive and colorant in rat plasma. The column used was Luna® C18 250×4.6 mm, 100 Å, having particle size 4.5 µm, and the mobile phase used was methanol (MeOH), and 10 mM ammonium acetate buffer in the ratio of 90 : 10, the flow rate was 1 ml/min, and the injection volume of 20 µL. The retention time of sodium copper chlorophyllin was obtained at 9 min. The method was found to be linear at the range of 0.50-8.00 µg mL-1 .

Diabetic nephropathy: The regulatory interplay between epigenetics and microRNAs.

Diabetic nephropathy (DN) is still one of the leading causes of end-stage renal disease despite the emergence of different therapies to counter the metabolic, hemodynamic and fibrotic pathways, implicating a prominent role of genetic and epigenetic factors in its progression. Epigenetics is the study of changes in the expression of genes which may be inheritable and does not involve a change in the genome sequence. Thrust areas of epigenetic research are DNA methylation and histone modifications. Noncoding RNAs (ncRNAs), particularly microRNAs (miRNAs) control the expression of genes via post-transcriptional mechanisms. However, the regulation by epigenetic mechanisms and miRNAs are not completely distinct. A number of emerging reports have revealed the interplay between epigenetic machinery and miRNA expression, particularly in cancer. Further research has proved that a feedback loop exists between miRNA expression and epigenetic regulation in disorders including DN. Studies showed that different miRNAs (miR-200, miR-29 etc.) were found to be regulated by epigenetic mechanisms viz. DNA methylation and histone modifications. Conversely, miRNAs (miR-301, miR-449 etc.) themselves modulated levels of DNA methyltranferases (DNMTs) and Histone deacetylases (HDACs), enzymes vital to epigenetic modifications. With already few FDA approved epigenetic -modulating drugs (Vorinostat, Decitabine) in the market and miRNA therapeutic drugs under clinical trial it becomes imperative to analyze the possible interaction between the two classes of drugs in the modulation of a disease process. The purpose of this review is to articulate the interplay between miRNA expression and epigenetic modifications with a particular focus on its impact on the development and progression of DN.

A Systematic Review on the Role of Natural Products in Modulating the Pathways in Alzheimer's Disease.

Alzheimer's disease (AD) is the most common neurodegenerative disorder to date, with no cure or preventive therapy. Histopathological hallmarks of AD include deposition of ß-amyloid plaques and formation of neurofibrillary tangles in brain. Despite extensive research, only five approved drugs are available for the management of AD. Hence, there is a need to look for alternative therapies and new drugs. Use of natural products in medicine has gained popularity in recent years and several natural compounds with neuroprotective effects have been studied in detail. Some of them target the disease pathways and improve cognition by directly affecting amyloidogenesis, programmed cell death and increase neuronal cell survival. Currently, phytochemicals like polyphenols, alkaloids, terpenes, flavonoids, tannins, saponins and vitamins from plants have received a special attention from the scientific community against the pathological processes in conditions like cancer, cardiovascular diseases and neurodegenerative diseases. Many efforts have been made to unravel the molecular mechanisms and the specific interactions of phytochemicals, which targets disease pathways in the AD. Further studies on these natural products and their mechanism of action, target specific effect in disease pathology parallel with the use of novel pharmaceutical drug design and delivery techniques, enable us to offer an addition to conventional medicine in treatment of AD. This review presents detailed information on natural products like polyphenols, alkaloids and terpenes with their potential effects in Alzheimer's disease.

Daidzein ameliorates peripheral neuropathy in Sprague Dawley rats.

Neuropathy is the most common disorder comprising peripheral nerve damage in diabetic patients. Prolonged hyperglycaemia and oxidative stress cause metabolic imbalance and are the key reasons for the development of diabetic neuropathy. Daidzein, a soy isoflavone possesses potent anti-hyperglycaemic and antioxidant activity. The present study aims to check the protective effect of Daidzein in diabetic neuropathy in rats. The experimental animal model involved induction of diabetes in rats by intraperitoneal injection of streptozotocin (55 mg/kg). Following confirmation of diabetes, the diabetic rats were subjected to oral treatment with varying doses of Daidzein (25, 50, and 100 mg/kg) and pregabalin (30 mg/kg) for a duration of 4 weeks, initiated 6 weeks after diabetes induction. Results indicated that Daidzein treatment led to a significant reduction in plasma glucose levels and an improvement in body weight among diabetic animals. Moreover, Daidzein demonstrated a positive impact on sensory functions, as evidenced by the effect on tail withdrawal and response latency. Mechanical hyperalgesia and allodynia, common symptoms of diabetic neuropathy, were also significantly reduced with both Daidzein and pregabalin treatment. Notably, nerve conduction velocities exhibited improvement following the administration of Daidzein and pregabalin. Further investigation into the molecular mechanisms revealed that Daidzein treatment resulted in a notable enhancement of antioxidant enzyme levels and a reduction in the overexpression of NOX-4 in the sciatic nerve. This suggests that Daidzein's therapeutic effect is associated with the inhibition of oxidative stress via NOX-4. In summary, the findings of study suggests that, Daidzein treatment significantly attenuated diabetic neuropathy by inhibiting oxidative stress via NOX-4 inhibition.