Abroma augusta L. (Malvaceae) leaf extract attenuates diabetes induced nephropathy and cardiomyopathy via inhibition of oxidative stress and inflammatory response

A Narrative Review of Signaling Pathway and Treatment Options for Diabetic Nephropathy

BACKGROUND

Diabetic nephropathy is a progressive kidney disease that frequently results in end-stage renal disorders and is characterized by proteinuria, albuminuria, decreased filtration, and renal fibrosis. Despite the fact that there are a number of therapeutic alternatives available, DN continues to be the main contributor to end-stage renal disease. Therefore, significant innovation is required to enhance outcomes in DN patients.

METHODS

Information was collected from online search engines like, Google Scholar, Web of Science, PubMed, Scopus, and Sci-Hub databases using keywords like diabetes, nephropathy, kidney disease, autophagy, etc. Results: Natural compounds have anti-inflammatory and antioxidant properties and impact various signaling pathways. They ameliorate kidney damage by decreasing oxidative stress, inflammatory process, and fibrosis and enhance the antioxidant system, most likely by activating and deactivating several signaling pathways. This review focuses on the role of metabolic memory and various signaling pathways involved in the pathogenesis of DN and therapeutic approaches available for the management of DN. Special attention is given to the various pathways modulated by the phytoconstituents.

Unveiling the apoptotic potential of antioxidant-rich Bangladeshi medicinal plant extractives and computational modeling to identify antitumor compounds

Nowadays, there has been a significant surge in the exploration of anticancer compounds derived from medicinal plants due to their perceived safety and efficacy. Therefore, our objective was to investigate the antioxidant and antiproliferative properties, along with the phytoconstituents, of methanol extracts from various parts of 15 selected Bangladeshi medicinal plants. Standard spectrophotometric methods and confocal microscopy were utilized to assess the antioxidant and antiproliferative potential of these extracts. Additionally, phytochemical profiling was executed through gas chromatography-mass spectrometry (GC-MS) analysis. Among the extractives, Bombax ceiba bark exhibited the highest scavenging capacity against DPPH (IC50: 10.3 ± 0.7 μg/mL) and hydroxyl (IC50: 3.9 ± 0.1 μg/mL) free radicals. Furthermore, the total antioxidants, reducing power, and polyphenols of B. ceiba bark were higher than those of other extracts. B. ceiba bark also showed significant antiproliferative capacity against MCF-7 cells (86.67 %) in the MTT assay, followed by Cocos nucifera roots (83.92 %), Bixa orellana leaves (44.09 %), and Leea macrophylla roots (25 %). Moreover, B. ceiba bark, L. macrophylla roots, C. nucifera roots, and B. orellana leaves-treated Ehrlich ascites carcinoma (EAC) cells demonstrated growth inhibition rates of 87.27 %, 80.45 %, 42.9 %, and 37.27 %, respectively. Fluorescence microscopic analysis of EAC cells treated with these extracts revealed apoptotic features such as condensed chromatin, cell shrinkage, nucleus fragmentation, and membrane blebbing compared to untreated EAC cells. The GC-MS analysis of B. ceiba bark identified 18 compounds, including various alcohols, alkenes, and esters. Additionally, a molecular docking study revealed oxalic acid, cyclohexyl dodecyl ester as the most potent compound (-6.5) active against breast cancer. In summary, our results demonstrate that B. ceiba bark possesses robust antioxidant and antiproliferative properties, along with potent antitumor compounds, which could be utilized in the treatment of carcinoma.

The role of serine/threonine protein kinases in cardiovascular disease and potential therapeutic methods

Protein phosphorylation is an important link in a variety of signaling pathways, and most of the important life processes in cells involve protein phosphorylation. Based on the amino acid residues of phosphorylated proteins, protein kinases can be categorized into the following families: serine/threonine protein kinases, tyrosine-specific protein kinases, histidine-specific protein kinases, tryptophan kinases, and aspartate/glutamyl protein kinases. Of all the protein kinases, most are serine/threonine kinases, where serine/threonine protein kinases are protein kinases that catalyze the phosphorylation of serine or threonine residues on target proteins using ATP as a phosphate donor. The current socially accepted classification of serine/threonine kinases is to divide them into seven major groups: protein kinase A, G, C (AGC), CMGC, Calmodulin-dependent protein kinase (CAMK), Casein kinase (CK1), STE, Tyrosine kinase (TKL) and others. After decades of research, a preliminary understanding of the specific classification and respective functions of serine/threonine kinases has entered a new period of exploration. In this paper, we review the literature of the previous years and introduce the specific signaling pathways and related therapeutic modalities played by each of the small protein kinases in the serine/threonine protein kinase family, respectively, in some common cardiovascular system diseases such as heart failure, myocardial infarction, ischemia-reperfusion injury, and diabetic cardiomyopathy. To a certain extent, the current research results, including molecular mechanisms and therapeutic methods, are fully summarized and a systematic report is made for the prevention and treatment of cardiovascular diseases in the future.

Fisetin Suppresses Atherosclerosis by Inhibiting Ferroptosis-Related Oxidative Stress in Apolipoprotein E Knockout Mice

INTRODUCTION

Fisetin has been demonstrated to inhibit the occurrence of atherosclerosis; however, the mechanism of fisetin suppressing atherosclerosis remains elusive.

METHODS

The function of fisetin in the inhibition of atherosclerosis was evaluated by hematoxylin and eosin and Oil Red O staining in ApoE-/- mice. Molecular biomarkers of atherosclerosis progression were detected by Western blot and qPCR. Moreover, the inhibition of atherosclerosis on oxidative stress and ferroptosis was evaluated by immunofluorescence staining, qPCR, and Western blot assays.

RESULTS

The obtained results showed that serum lipid was attenuated and consequentially the formation of atherosclerosis was also suppressed by fisetin in ApoE-/- mice. Exploration of the mechanism revealed that molecular biomarkers of atherosclerosis were decreased under fisetin treatment. The level of reactive oxygen species and malondialdehyde declined, while the activity of superoxide dismutases and glutathione peroxidase was increased under the fisetin treatment. Additionally, the suppressor of ferroptosis, glutathione peroxidase 4 proteins, was elevated. The ferritin was decreased in the aortic tissues treated with fisetin.

CONCLUSIONS

In summary, fisetin attenuated the formation of atherosclerosis through the inhibition of oxidative stress and ferroptosis in the aortic tissues of ApoE-/- mice.

Phytochemicals and Their Usefulness in the Maintenance of Health

Inflammation is the immune system's first biological response to infection, injury, or irritation. Evidence suggests that the anti-inflammatory effect is mediated by the regulation of various inflammatory cytokines, such as nitric oxide, interleukins, tumor necrosis factor alpha-α, interferon gamma-γ, as well as the non-cytokine mediator, prostaglandin E2. Currently, the mechanism of action and clinical usefulness of phytochemicals is known; their action on the activity of cytokines, free radicals, and oxidative stress. The latter are of great relevance in the development of diseases, such that the evidence collected demonstrates the beneficial effects of phytochemicals in maintaining health. Epidemiological evidence indicates that regular consumption of fruits and vegetables is related to a low risk of developing cancer and other chronic diseases.

New Horizons in Diabetic Neuropathies: An Updated Review on their Pathology, Diagnosis, Mechanism, Screening Techniques, Pharmacological, and Future Approaches

BACKGROUND

One of the largest problems for global public health is diabetes mellitus (DM) and its micro and macrovascular consequences. Although prevention, diagnosis, and treatment have generally improved, its incidence is predicted to keep rising over the coming years. Due to the intricacy of the molecular mechanisms, which include inflammation, oxidative stress, and angiogenesis, among others, discovering treatments to stop or slow the course of diabetic complications is still a current unmet need.

METHODS

The pathogenesis and development of diabetic neuropathies may be explained by a wide variety of molecular pathways, hexosamine pathways, such as MAPK pathway, PARP pathway, oxidative stress pathway polyol (sorbitol) pathway, cyclooxygenase pathway, and lipoxygenase pathway. Although diabetic neuropathies can be treated symptomatically, there are limited options for treating the underlying cause.

RESULT

Various pathways and screening models involved in diabetic neuropathies are discussed, along with their possible outcomes. Moreover, both medicinal and non-medical approaches to therapy are also explored.

CONCLUSION

This study highlights the probable involvement of several processes and pathways in the establishment of diabetic neuropathies and presents in-depth knowledge of new therapeutic approaches intended to stop, delay, or reverse different types of diabetic complications.

Therapeutic application of natural products: NAD+ metabolism as potential target

BACKGROUND

Nicotinamide adenine dinucleotide (NAD⁺) metabolism is involved in the entire physiopathological process and is critical to human health. Long-term imbalance in NAD⁺ homeostasis is associated with various diseases, including non-alcoholic fatty liver disease, diabetes mellitus, cardiovascular diseases, neurodegenerative disorders, aging, and cancer, making it a potential target for effective therapeutic strategies. Currently, several natural products that target NAD⁺ metabolism have been widely reported to have significant therapeutic effects, but systematic summaries are lacking.

PURPOSE

To summarize the latest findings on the prevention and treatment of various diseases through the regulation of NAD⁺ metabolism by various natural products in vivo and in vitro models, and evaluate the toxicities of the natural products.

METHODS

PubMed, Web of Science, and ScienceDirect were searched using the keywords "natural products sources," "toxicology," "NAD⁺ clinical trials," and "NAD⁺," and/or paired with "natural products" and "diseases" for studies published within the last decade until January 2023.

RESULTS

We found that the natural products mainly include phenols (curcumin, cyclocurcumin, 4-hydroxybenzyl alcohol, salvianolic acid B, pterostilbene, EGCG), flavonoids (pinostrobin, apigenin, acacetin, tilianin, kaempferol, quercetin, isoliquiritigenin, luteolin, silybin, hydroxysafflor yellow A, scutellarin), glycosides (salidroside), quinones (emodin, embelin, β-LAPachone, shikonin), terpenoids (notoginsenoside R1, ginsenoside F2, ginsenoside Rd, ginsenoside Rb1, ginsenoside Rg3, thymoquinone, genipin), pyrazines (tetramethylpyrazine), alkaloids (evodiamine, berberine), and phenylpropanoids (ferulic acid). These natural products have antioxidant, energy-producing, anti-inflammatory, anti-apoptotic and anti-aging effects, which mainly influence the NAMPT/NAD⁺/SIRT, AMPK/SIRT1/PGC-1α, Nrf2/HO-1, PKCs/PARPs/NF-κB, and AMPK/Nrf2/mTOR signaling pathways, thereby regulating NAD⁺ metabolism to prevent and treat various diseases. These natural products have been shown to be safe, tolerable and have fewer adverse effects in various in vivo and in vitro studies and clinical trials.

CONCLUSION

We evaluated the toxic effects of natural products and summarized the available clinical trials on NAD⁺ metabolism, as well as the recent advances in the therapeutic application of natural products targeting NAD⁺ metabolism, with the aim to provide new insights into the treatment of multiple disorders.

Synthesis, in-Silico studies and biological evaluation of pyrimidine based thiazolidinedione derivatives as potential anti-diabetic agent

Despite the advancements in the management of Diabetes mellitus, the design and synthesis of drug molecule which ameliorates the hyperglycemia and associated secondary complications in diabetic patients, still remains a challenge. Herein, we report the synthesis, characterization and anti-diabetic evaluation of pyrimidine-thiazolidinedione derivatives. The synthesized compounds were characterized by 1H NMR, 13C NMR, FTIR and Mass Spectroscopic analytical techniques. The in-silico ADME studies depicted that the compounds were within the permissible limits of the Lipinski's rule of five. The compounds 6e and 6m showing the best results in OGTT were evaluated for in-vivo anti-diabetic evaluation in STZ induced diabetic rats. Administration of 6e and 6m for four weeks decreased the blood glucose levels significantly. Compound 6e (4.5 mg/kg p.o.) was the most potent compound of the series. It reduced the level of blood glucose to 145.2 ± 1.35 compared to the standard Pioglitazone (150.2 ± 1.06). Moreover, the 6e and 6m treated group did not show increase in bodyweight. The biochemical estimations showed that the levels of ALT, ASP, ALP, urea, creatinine, blood urea nitrogen, total protein and LDH restored to normal in 6e and 6m treated groups as compared to STZ control group. The histopathological studies supported the results obtained in biochemical estimations. Both the compounds did not show any toxicity. Moreover, the histopathological studies of pancreas, liver, heart and kidney revealed that the structural integrity of these tissues restored to almost normal in 6e and 6m treated groups as compared to STZ control group. Based upon these findings it can be concluded that the pyrimidine-based thiazolidinedione derivatives represent novel anti-diabetic agents with least side effects.

Exploring the Complex Relationship between Diabetes and Cardiovascular Complications: Understanding Diabetic Cardiomyopathy and Promising Therapies

Diabetes mellitus (DM) and cardiovascular complications are two unmet medical emergencies that can occur together. The rising incidence of heart failure in diabetic populations, in addition to apparent coronary heart disease, ischemia, and hypertension-related complications, has created a more challenging situation. Diabetes, as a predominant cardio-renal metabolic syndrome, is related to severe vascular risk factors, and it underlies various complex pathophysiological pathways at the metabolic and molecular level that progress and converge toward the development of diabetic cardiomyopathy (DCM). DCM involves several downstream cascades that cause structural and functional alterations of the diabetic heart, such as diastolic dysfunction progressing into systolic dysfunction, cardiomyocyte hypertrophy, myocardial fibrosis, and subsequent heart failure over time. The effects of glucagon-like peptide-1 (GLP-1) analogues and sodium-glucose cotransporter-2 (SGLT-2) inhibitors on cardiovascular (CV) outcomes in diabetes have shown promising results, including improved contractile bioenergetics and significant cardiovascular benefits. The purpose of this article is to highlight the various pathophysiological, metabolic, and molecular pathways that contribute to the development of DCM and its significant effects on cardiac morphology and functioning. Additionally, this article will discuss the potential therapies that may be available in the future.

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

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

Effect of S-allylcysteine against diabetic nephropathy via inhibition of MEK1/2-ERK1/2-RSK2 signalling pathway in streptozotocin-nicotinamide-induced diabetic rats

OBJECTIVE

In the current study, we evaluated the ameliorative effect of S-allylcysteine (SAC) against streptozotocin (STZ)-nicotinamide (NAD)-induced diabetic nephropathy (DN) in rats and also an attempt was made to establish the molecular mechanism of SAC.

METHODS

DN rats were orally supplemented with SAC (150 mg/kg body weight) for a period of 45 days and the effect of SAC on urinary albumin excretion, metabolic parameters, and tubular injury biomarkers by ELISA, total levels and phosphorylation of MEK1/2, ERK1/2, and RSK2 by western blotting analysis in control and experimental rats were assessed.

RESULTS

From this study, we observed that SAC considerably decreased polydipsia, poly urea, polyphagia, albuminuria and the levels of urinary N-acetyl-beta-D-glucosaminidase, neutrophil gelatinase-associated lipocalin, transforming growth factor-β1 and SAC effectively altered the pathological changes in DN rats. SAC also reserved renal cortical phosphorylation of MEK1/2, ERK1/2 and RSK2.

CONCLUSION

Hence this study recommended that SAC can successfully protect the DN through regulation of MEK1/2-ERK1/2-RSK2 signalling.

Impact of atorvastatin on plasma and cardiac biomarkers of inflammation, oxidative stress, and fibrosis in a rat model of streptozotocin-induced diabetes

Oxidative stress and fibrosis foster the development of cardiovascular disease (CVD) in diabetes. Atorvastatin protects against cardiovascular diseases in diabetes patients. However, the mechanisms are not completely known. This study evaluated the impact of atorvastatin on vascular and myocardial oxidative stress, inflammation, and fibrosis in a model of diabetes. Male Wistar rats were assigned into four groups; control rats, atorvastatin-treated rats (Ator, 40 mg/kg given by oral gavage for 6 weeks), diabetes rats (DM, single IP 40 mg/kg streptozotocin), and diabetes rats treated with atorvastatin (DM + Ator). Serum and cardiac inflammatory, oxidant, and fibrotic markers were measured. Cardiac fibrosis was evaluated by Masson trichrome stain. Streptozotocin-induced diabetes as documented by the marked elevation in blood glucose. Levels of oxidant biomarkers of serum and cardiac nitrite, cardiac nitrate, and cardiac thiobarbituric acid reactive substances (TBARS) were increased in the DM group. The use of atorvastatin reduced nitrite and TBARS levels. Serum and cardiac inflammatory factors of endothelin-1 (ET-1) were elevated in the DM group, and the use of atorvastatin reduced these increases. Cardiac C-reactive protein tended to increase in the DM group and the use of atorvastatin reduced its level. Cardiac interstitial fibrosis was increased in the DM group with a parallel increase in the platelet-derived growth factor level. The use of atorvastatin reduced cardiac fibrosis. Diabetes was associated with an increase in serum and/or myocardial markers of oxidative stress, inflammation, and fibrosis. The use of atorvastatin reduced cardiac interstitial fibrosis and decreased cardiac oxidant and inflammatory biomarkers.

Umbelliferone attenuates diabetic cardiomyopathy by suppression of JAK/STAT signaling pathway through amelioration of oxidative stress and inflammation in rats

Umbelliferone (UMB), 7-hydroxycoumarin, is a naturally occurring coumarin derivative that has a plethora of biological and therapeutic activities. The focus of this research was to elucidate the curative effects of two different doses of UMB on diabetic cardiomyopathy (DCM) in a type 2 diabetic rat model induced by 50 mg/kg body weight of streptozotocin (STZ). Diabetic rats orally received 10 or 30 mg/kg of UMB daily for 8 weeks. Compared to the nontreated diabetic group, both UMB treatment doses significantly decreased glucose levels, glycated hemoglobin (HbA1c), tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), creatine kinase MB (CK-MB), cardiovascular risk indices, and oxidative stress by reducing malondialdehyde (MDA) and increasing the activity of the antioxidant enzymes. The hypercholesterolemia and hypertriglyceridemia also dramatically decreased in diabetic groups with UMB treatments accompanied by an improvement in insulin, and insulin sensitivity indices (HOMA-IR and QUICKI). Furthermore, the cardiac gene expressions and protein levels of Janus kinase2 (JAK2), signal transducer and activator of transcription3 (STAT3), and transforming growth factor beta1 (TGF-β1) were also markedly downregulated in a dose-dependent manner by UMB treatments. Finally, the biochemical results were assured by the reduction of histological alterations in cardiac tissues. In conclusion, UMB is a propitious substance for the treatment of DCM by virtuousness of its antihyperglycemic, antihyperlipidemic, antioxidant, and anti-inflammatory properties through modulating the JAK/STAT signaling pathway that may be the underlying mechanism in UMB action.

The impact of oxidative stress-induced mitochondrial dysfunction on diabetic microvascular complications

Diabetes mellitus (DM) is a metabolic disease characterized by chronic hyperglycaemia, with absolute insulin deficiency or insulin resistance as the main cause, and causes damage to various target organs including the heart, kidney and neurovascular. In terms of the pathological and physiological mechanisms of DM, oxidative stress is one of the main mechanisms leading to DM and is an important link between DM and its complications. Oxidative stress is a pathological phenomenon resulting from an imbalance between the production of free radicals and the scavenging of antioxidant systems. The main site of reactive oxygen species (ROS) production is the mitochondria, which are also the main organelles damaged. In a chronic high glucose environment, impaired electron transport chain within the mitochondria leads to the production of ROS, prompts increased proton leakage and altered mitochondrial membrane potential (MMP), which in turn releases cytochrome c (cyt-c), leading to apoptosis. This subsequently leads to a vicious cycle of impaired clearance by the body's antioxidant system, impaired transcription and protein synthesis of mitochondrial DNA (mtDNA), which is responsible for encoding mitochondrial proteins, and impaired DNA repair systems, contributing to mitochondrial dysfunction. This paper reviews the dysfunction of mitochondria in the environment of high glucose induced oxidative stress in the DM model, and looks forward to providing a new treatment plan for oxidative stress based on mitochondrial dysfunction.

Gingerol, a Natural Antioxidant, Attenuates Hyperglycemia and Downstream Complications

Hyperglycemia is seen in approximately 68 percent of patients admitted to a medical intensive care unit (ICU). In many acute circumstances, such as myocardial infarction, brain, injury and stroke, it is an independent predictor of mortality. Hyperglycemia is induced by a mix of genetic, environmental, and immunologic variables in people with type 1 diabetes. These factors cause pancreatic beta cell death and insulin insufficiency. Insulin resistance and irregular insulin production cause hyperglycemia in type 2 diabetes patients. Hyperglycemia activates a number of complicated interconnected metabolic processes. Hyperglycemia is a major contributor to the onset and progression of diabetes' secondary complications such as neuropathy, nephropathy, retinopathy, cataracts, periodontitis, and bone and joint issues. Studies on the health benefits of ginger and its constituent's impact on hyperglycemia and related disorders have been conducted and gingerol proved to be a potential pharmaceutically active constituent of ginger (Zingiber officinale) that has been shown to lower blood sugar levels, because it possesses antioxidant properties and it functions as an antioxidant in the complicated biochemical process that causes hyperglycemia to be activated. Gingerol not only helps in treating hyperglycemia but also shows effectivity against diseases related to it, such as cardiopathy, kidney failure, vision impairments, bone and joint problems, and teeth and gum infections. Moreover, fresh ginger has various gingerol analogues, with 6-gingerol being the most abundant. However, it is necessary to investigate the efficacy of its other analogues against hyperglycemia and associated disorders at various concentrations in order to determine the appropriate dose for treating these conditions.

Polyphenols target miRNAs as a therapeutic strategy for diabetic complications

MiRNAs are a large group of non-coding RNAs which participate in different cellular pathways like inflammation and oxidation through transcriptional, post-transcriptional, and epigenetic regulation. In the post-transcriptional regulation, miRNA interacts with the 3'-UTR of mRNAs and prevents their translation. This prevention or dysregulation can be a cause of pathological conditions like diabetic complications. A huge number of studies have revealed the association between miRNAs and diabetic complications, including diabetic nephropathy, cardiomyopathy, neuropathy, retinopathy, and delayed wound healing. To address this issue, recent studies have focused on the use of polyphenols as selective and safe drugs in the treatment of diabetes complications. In this article, we will review the involvement of miRNAs in diabetic complications' occurrence or development. Finally, we will review the latest findings on targeting miRNAs by polyphenols like curcumin, resveratrol, and quercetin for diabetic complications therapy.

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.

Ameliorative effects of Artemisia and Echinacea extracts against hepato and cardiotoxicity induced by DMBA on albino rats: experimental and molecular docking analyses

Background

Herbal therapy for healing disease has many advantages than drugs. This study investigates the protective efficacy of Artemisia annua (Art) and Echinacea pupurea (Ech) extracts against 7, 12-dimethylbenz (α) anthracene (DMBA) toxicity.

Results

DMBA-treated rats showed a significant increase in the level of serum ALT, AST, LDH and CKMB, also reduction in body weight gain (BWG) ℅, HB, WBCs, RBCs and platelet counts, in addition to histopathological and ultrastructural alterations. Rats treated with Art or Ech after DMBA showed little improvements in the biochemical, hematological, histopathological, ultrastructural and molecular docking results than before DMBA.

Conclusions

This study suggested the ameliorative effect of Ech and Art due to their antioxidant properties, but Ech and Art were more effective if they are given before than after DMBA administration and the marked effect against DMBA toxicity with Ech before DMBA exposure. Also, the molecular docking, molecular properties descriptors, and pharmacoinformatic studies of constituents of extract from Artemisia annua L. and Echinacea purpurea L. exhibited that all studied compounds have better ADMET and physicochemical properties, especially compounds extract from Echinacea purpurea L.

Graphical Abstract

Carnosic acid attenuates doxorubicin-induced cardiotoxicity by decreasing oxidative stress and its concomitant pathological consequences

This work aimed to reveal the protective mechanism of CA against Dox (doxorubicin)-induced cardiotoxicity. In isolated murine cardiomyocytes, CA showed a concentration-dependent cytoprotective effect against Dox. Dox treatment significantly (p < 0.01) increased the formation of reactive oxygen species (ROS), increased NO levels, activated NADPH oxidase, and inactivated the cellular redox defense mechanism in cardiac cells, resulting in augmented oxidative stress in cardiomyocytes and rat hearts. Dox-induced oxidative stress significantly (p < 0.01) upregulated several pathogenic signal transductions, which induced apoptosis, inflammation, and fibrosis in cardiomyocytes and murine hearts. In contrast, CA significantly (p < 0.05-0.01) reciprocated Dox-induced cardiac apoptosis, inflammation, and fibrosis by suppressing oxidative stress and interfering with pathological signaling events in both isolated murine cardiomyocytes and rat hearts. CA treatment significantly (p < 0.05-0.01) countered Dox-mediated pathological changes in blood parameters in rats. Histological examinations backed up the pharmacological findings. In silico chemometric investigations predicted potential interactions between CA and studied signal proteins, as well as the drug-like features of CA. Thus, it would be concluded that CA has the potential to be regarded as an effective agent to alleviate Dox-mediated cardiotoxicity in the future.

Catechins as a Potential Dietary Supplementation in Prevention of Comorbidities Linked with Down Syndrome

Plant-derived polyphenols flavonoids are increasingly being recognized for their medicinal potential. These bioactive compounds derived from plants are gaining more interest in ameliorating adverse health risks because of their low toxicity and few side effects. Among them, therapeutic approaches demonstrated the efficacy of catechins, a major group of flavonoids, in reverting several aspects of Down syndrome, the most common genomic disorder that causes intellectual disability. Down syndrome is characterized by increased incidence of developing Alzheimer's disease, obesity, and subsequent metabolic disorders. In this focused review, we examine the main effects of catechins on comorbidities linked with Down syndrome. We also provide evidence of catechin effects on DYRK1A, a dosage-sensitive gene encoding a protein kinase involved in brain defects and metabolic disease associated with Down syndrome.

Pharmacological studies of rhizomes of extract of Cyperus tegetum, emphasized on anticancer, anti-inflammatory and analgesic activity

ETHNOPHARMACOLOGICAL RELEVANCE

With over 950 species, Cyperus is one of the most promising health boosting genera in the Cyperaceae family. Traditional uses of Cyperus sp. have been described for gastrointestinal blood abnormalities, menstrual irregularities, and inflammatory diseases, among others. Cyperus tegetum Roxb belonging to Cyperaceae family, is used in traditional medicine to treat skin cancers.

AIM OF THE STUDY

The present study was carried out to explore the potential effect of the extract of the plant Cyperus tegetum against different pharmacological activity namely inflammatory, analgesic activity as well as skin cancer activity in mice.

MATERIALS AND METHODS

Cytotoxicity of the extract was measured by MTT and Live/death assay on HeLa cell line. Skin cancer was induced by 7,12-dimethylbenz(a) anthracene (DMBA) and 12-O-tetradecanoylphorbol-13-acetate (TPA) in mice to measure its effects.

RESULT

Stigmasterol and some poly phenolic compounds are identified using HPTLC process from the methanol extract of the rhizome of the plant Cyperus tegetum (CT-II). After confirmation of the presence of different polyphenolic compound and triterpenoids in the extract, it was subject to MTT and Live/death assay on HeLa cell line. From the observation it could be concluded that the IC₅₀ of the extract is 300 μg/ml. Thus, the CTII was evaluated further for its in vivo anticancer property. In the tumorigenesis study, the number of tumor growths, the area and weight of the tumor significantly decreases with increment in the dose of CT-II extract and some elevated enzyme release in renal (creatinine, urea) as well as hepatic (AST, ALT, ALP) enzymes are also controlled with the increased dose of the same extract. The elevated enzyme release may be due to cancer induced rupture of the plasma and cellular damage. This CT-II extract also exhibits some other pharmacological activity like anti-inflammatory and analgesic activity.

CONCLUSION

As metabolic activation via carcinogens and inflammation response plays important role in development of cancer, antioxidant, anti-inflammatory and analgesic properties can be correlated with anti-cancer properties. Taken all the above studies, it was illustrated that the extract of Cyperus tegetum might be a promising compound to reduce skin cancer risk.

Aqueous extract of Solanum macrocapon Linn leaf abate diabetic cardiomyopathy by attenuating oxidative stress and inflammation in rats

In this research, the beneficial roles of aqueous leaf extract of Solanum macrocarpon (SM) on diabetic cardiomyopathy were evaluated. Diabetic rats (induced with alloxan) were given varying doses of SM aqueous leaves extract for 28 days, and the animals were sacrificed. A series of diabetic cardiomyopathy parameters were determined. Diabetic rats showed hyperglycemia, hyperlipidemia, with a momentous upsurge in lactate dehydrogenase, creatine kinase, cardiac troponin I activities as well as inflammatory markers. Also, diabetic rats demonstrated a substantial decline in the activities of antioxidant enzymes in relation to other groups. Administration of different doses of SM aqueous leaf extract to diabetic rats demonstrated normoglycemia, normolipidemia, reduced the activities of lactate dehydrogenase, creatine kinase, cardiac troponin I, and inflammatory levels as well as an increase in the antioxidant enzyme activities. In conclusion, the results suggest that SM aqueous leaf extract ameliorates diabetic cardiomyopathy. PRACTICAL APPLICATIONS: This study examined the role of Solanum macrocarpon (SM) aqueous leaf extract in diabetic cardiomyopathy. Results revealed that SM might be useful in ameliorating diabetic cardiomyopathy.

The Biosynthesis and Medicinal Properties of Taraxerol

Taraxerol is a pentacyclic triterpenoid that is actively produced by some higher plants as part of a defense mechanism. The biosynthesis of taraxerol in plants occurs through the mevalonate pathway in the cytosol, in which dimethylallyl diphosphate (DMAPP) and isopentyl pyrophosphate (IPP) are first produced, followed by squalene. Squalene is the primary precursor for the synthesis of triterpenoids, including taraxerol, β-amyrin, and lupeol, which are catalyzed by taraxerol synthase. Taraxerol has been extensively investigated for its medicinal and pharmacological properties, and various biotechnological approaches have been established to produce this compound using in vitro techniques. This review provides an in-depth summary of the hypothesized taraxerol biosynthetic pathway, the medicinal properties of taraxerol, and recent developments on tissue culture for the in vitro production of taraxerol.

Physicians' Perception About Use of Vitamin B12 in the Treatment or Prevention of Diabetic Neuropathy: A Cross-sectional Survey in Saudi Arabia

BACKGROUND

Diabetic neuropathy is a condition that is prevalent among type 2 diabetic patients. Some physicians prescribe vitamin B12 or vitamin B complex supplements to improve symptoms, but studies have shown that there is little to no evidence of vitamin B12 being an effective treatment for diabetic neuropathy. Thus, this study aims to investigate local physicians' knowledge and tendency to prescribe vitamin B12 or vitamin B complex for the treatment or prevention of diabetic peripheral neuropathy.

METHODS

It was a cross-sectional study, conducted between May and November of 2019, in several primary healthcare centers in different cities of Saudi Arabia. A total of 412 physicians with a minimum of three years of experience answered a three-part questionnaire on their demographic information, prescribing behavior, and knowledge of the relationship between vitamin B12 or vitamin B complex and diabetic neuropathy.

RESULTS

The study found that only 42% of the physicians believed that vitamin B12 supplementation did not prevent diabetic neuropathy, while only 52.7% found it to be an ineffective treatment for this condition. Moreover, 58.7% stated that they had certainly prescribed vitamin B12 or multivitamins as a form of treatment or prevention of diabetic neuropathy. 47.8% of the patients requested a vitamin B12 prescription 1-6 times from their physicians, while 31.6% of them requested it ≥ 7 times, with 42.5% of physicians agreeing that their prescriptions of vitamin B12 had been a result of patient demand more than clinical justification. Likewise, 43% of respondents were aware that vitamin B12 levels should be tested annually. Furthermore, a higher proportion of consultants chose not to prescribe vitamin B12 to prevent or treat diabetic neuropathy than any other rank.

CONCLUSION

The findings of this study indicate a tendency of unnecessarily prescribing vitamin B12 supplementation for the prevention or treatment of diabetic neuropathy as well as a lack of knowledge on the matter among doctors in primary care hospitals in Saudi Arabia. The study has also shown that there are patients who often request this prescription, adding pressure on their physicians to comply. Future studies should investigate most of the hospitals in Saudi cities and include less experienced residents and medical students.

Polyherbal Formulation Ameliorates Diabetic Cardiomyopathy Through Attenuation of Cardiac Inflammation and Oxidative Stress Via NF-κB/Nrf-2/HO-1 Pathway in Diabetic Rats

ABSTRACT

The present study was intended to evaluate the effect of polyherbal formulation (PHF) made with 3 nutraceuticals, such as Piper nigrum, Terminalia paniculata, and Bauhinia purpurea on inflammation and oxidative stress in diabetic cardiomyopathy (DCM), which is induced by streptozotocin and nicotinamide administration in rats. We supplemented DCM rats with PHF (250 and 500 mg/kg/BW) for 45 days and evaluated their effects on oxidative stress markers, proinflammatory cytokines, and messenger RNA expressions of the nuclear factor erythroid 2-related factor-2 (Nrf-2) and its linked genes [heme oxygenase-1 (HO-1), superoxide dismutase, catalase] along with inflammatory genes [tumour necrosis factor α and nuclear factor kappa B (NF-κB)]. Our study demonstrated that PHF successfully attenuated inflammation and oxidative stress via messenger RNA upregulation of Nrf-2, HO-1, superoxide dismutase, and catalase and concomitantly with downregulation of tumour necrosis factor α and NF-κB. Conversely, PHF also protected hyperglycemia-mediated cardiac damage, which was confirmed with histopathological and scanning electron microscopy analysis. In conclusion, our results suggested that PHF successfully ameliorated hyperglycemia-mediated inflammation and oxidative stress via regulation of NF-κB/Nrf-2/HO-1 pathway. Therefore, these results recommend that PHF may be a prospective therapeutic agent for DCM.

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.

Therapeutic Approach of Flavonoid in Ameliorating Diabetic Cardiomyopathy by Targeting Mitochondrial-Induced Oxidative Stress

Diabetes cardiomyopathy is one of the key factors of mortality among diabetic patients around the globe. One of the prior contributors to the progression of diabetic cardiomyopathy is cardiac mitochondrial dysfunction. The cardiac mitochondrial dysfunction can induce oxidative stress in cardiomyocytes and was found to be the cause of majority of the heart morphological and dynamical changes in diabetic cardiomyopathy. To slow down the occurrence of diabetic cardiomyopathy, it is crucial to discover therapeutic agents that target mitochondrial-induced oxidative stress. Flavonoid is a plentiful phytochemical in plants that shows a wide range of biological actions against human diseases. Flavonoids have been extensively documented for their ability to protect the heart from diabetic cardiomyopathy. Flavonoids' ability to alleviate diabetic cardiomyopathy is primarily attributed to their antioxidant properties. In this review, we present the mechanisms involved in flavonoid therapies in ameliorating mitochondrial-induced oxidative stress in diabetic cardiomyopathy.

Bee venom ameliorates cardiac dysfunction in diabetic hyperlipidemic rats

High levels of blood glucose and lipids are well-known risk factors for heart diseases. Bee venom is a natural product that has a potent hypoglycemic, hypolipidemic, anti-inflammatory, and antioxidant effects. The current study aimed to determine the bee venom effects on cardiac dysfunction compared to combined therapy of metformin and atorvastatin in diabetic hyperlipidemic rats. The median lethal dose of bee venom was estimated, and then 50 adult male albino rats were categorized into five groups. One group was fed a standard diet and served as a negative control, while the other groups were given nicotinamide and streptozotocin injections to induce type 2 diabetes. After confirming diabetes, the rats were fed a high-fat diet for four weeks. The four groups were divided as follows: one group served as a positive control, whereas the other three groups were treated with bee venom (0.5 mg/kg), bee venom (1.23 mg/kg), and combined therapy of metformin (60 mg/kg) and atorvastatin (10 mg/kg), respectively, for four weeks. Upon termination of the experiment, blood samples and heart tissue were obtained. Administration of bee venom using both doses (0.5 and 1.23 mg/kg) and combined therapy of metformin and atorvastatin revealed a significant decrease in the concentrations of glucose, total cholesterol, triacylglycerol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, troponin I, creatine kinase, and lactate dehydrogenase activities. Moreover, a significant decrease had been detedcted in malondialdehyde, nuclear factor-kappa-β levels, and relative mRNA expression of vascular cell adhesion molecule-1 and galectin-3 in heart tissue compared to the positive control (P < 0.0001). Furthermore, there was a significant increase in bodyweight levels of insulin, high-density lipoprotein cholesterol, and total antioxidant capacity in heart tissue compared to the positive control (P < 0.0001). The results indicate that bee venom can ameliorate cardiac dysfunction through attenuating oxidative stress and downregulating the NF-κβ signaling pathway.

Recent Insights into the Nutritional Antioxidant Therapy in Prevention and Treatment of Diabetic Vascular Complications - A comprehensive Review

Diabetes mellitus (DM) and DM-induced vascular complications are a significant global healthcare problem causing a decrease in patient quality of life. The main reason for the disability and mortality of patients is rapidly progressing micro- and macroangiopathies. Currently, free radical oxidation is recognized as one of the main mechanisms in the development of DM and associated complications. Under normal physiological conditions, the level of free radicals and antioxidant defense capabilities is balanced. However, imbalance occurs between the antioxidant defense system and pro-oxidants during chronic hyperglycemia and may invoke formation of excess free radicals, leading to activation of lipid peroxidation and accumulation of highly toxic products of free radical oxidation. This is accompanied by varying degrees of insulin deficiency and insulin resistance in DM patients. Simultaneously with the activation of free radical generation, a decrease in the activity of antioxidant defense factors (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, vitamins C and E) and an acceleration of diabetic complications is seen. Therefore, we hypothesize that antioxidants may play a positive role in the treatment of DM patients to prevent DM-induced vascular complications. However this has not been sufficiently studied. In this review, we discuss recent insights into the potential underlying mechanisms of oxidative stress induced diabetic complications, and implications of antioxidants in mitigation of DM-induced vascular complications.

The Emerging Role of HDACs: Pathology and Therapeutic Targets in Diabetes Mellitus

Diabetes mellitus (DM) is one of the principal manifestations of metabolic syndrome and its prevalence with modern lifestyle is increasing incessantly. Chronic hyperglycemia can induce several vascular complications that were referred to be the major cause of morbidity and mortality in DM. Although several therapeutic targets have been identified and accessed clinically, the imminent risk of DM and its prevalence are still ascending. Substantial pieces of evidence revealed that histone deacetylase (HDAC) isoforms can regulate various molecular activities in DM via epigenetic and post-translational regulation of several transcription factors. To date, 18 HDAC isoforms have been identified in mammals that were categorized into four different classes. Classes I, II, and IV are regarded as classical HDACs, which operate through a Zn-based mechanism. In contrast, class III HDACs or Sirtuins depend on nicotinamide adenine dinucleotide (NAD+) for their molecular activity. Functionally, most of the HDAC isoforms can regulate β cell fate, insulin release, insulin expression and signaling, and glucose metabolism. Moreover, the roles of HDAC members have been implicated in the regulation of oxidative stress, inflammation, apoptosis, fibrosis, and other pathological events, which substantially contribute to diabetes-related vascular dysfunctions. Therefore, HDACs could serve as the potential therapeutic target in DM towards developing novel intervention strategies. This review sheds light on the emerging role of HDACs/isoforms in diabetic pathophysiology and emphasized the scope of their targeting in DM for constituting novel interventional strategies for metabolic disorders/complications.

The protective role of Coenzyme Q10 in metallothionein-3 expression in liver and kidney upon rats' exposure to lead acetate

Metallothionein-3 (MT3) is an antioxidant protein that alters after exposure to heavy metals. In this study, we investigated the hepatic and renal expression of MT3 gene following exposure to lead acetate (PbAc) alone and PbAc plus CoQ10 as an adjuvant antioxidant. Twenty-four rats were allocated into three groups, including control, PbAc (free access to drinking water contaminated with PbAc at 1 g/100 ml), and PbAc plus CoQ10 (10 mg/kg/day Oral). After 28 consecutive days of treatment, the mRNA expression of MT3 and Cyt-c genes and MT3 protein levels were assessed using real-time PCR and immunosorbent assay. The serum lipid profile was also monitored in the three groups. PbAc exposure significantly reduced the hepatic and renal MT3 mRNA and protein expression compared to the control group. This reduction was significantly increased with addition of CoQ10 to levels near those of the control group. The hepatic and renal expression of Cyt-c mRNA increased after treatment with PbAc, while such effect was reversed after addition of CoQ10. Alteration in lipid profile including increased cholesterol and low-density lipoprotein levels were observed after PbAc exposure which were counteracted by CoQ10. Our results confirm the cytotoxic effects of acute lead exposure manifested as changes in the serum lipid profile and cellular levels of Cyt-c mRNA. These cytotoxic effects may have been caused by decreased MT3 gene expression and be reduced by the protective role of CoQ10.

Melatonin protects the heart and pancreas by improving glucose homeostasis, oxidative stress, inflammation and apoptosis in T2DM-induced rats

Cardiomyopathy and pancreatic injury are health issues associated with type 2 diabetes mellitus (T2DM) and are characterized by elevated oxidative stress, inflammation and apoptosis. Melatonin (MLT) is a hormone with multifunctional antioxidant activity. The protective effects of MLT on the heart and pancreas during the early development of diabetic cardiomyopathy and pancreatic injury were investigated in male Wistar rats with T2DM. MLT (10 mg/kg) was administered daily by gavage for 15 days after diabetic induction. Treatment of diabetic rats with MLT significantly normalized the levels of serum glucose, HbA1-c, and the lipid profile and improved the insulin levels and insulin resistance compared with diabetic rats, affirming its antidiabetic effect. MLT significantly prevented the development of oxidative stress and sustained the levels of glutathione and glutathione peroxidase activity in the heart and pancreas of diabetic animals, indicating its antioxidant capacity. Additionally, MLT prevented the increase in proinflammatory cytokines and expression of Bax, caspase-3 and P53. Furthermore, MLT enhanced the anti-inflammatory cytokine IL-10 and antiapoptotic protein Bcl-2. MLT controlled the levels of troponin T and creatine kinase-MB and lactate dehydrogenase activity, indicating its anti-inflammatory and antiapoptotic effects. Histological examinations confirmed the protective effects of MLT on T2DM-induced injury in the myocardium, pancreas and islets of Langerhans. In conclusion, the protective effects of melatonin on the heart and pancreas during the early development of T2DM are attributed to its antihyperglycemic, antilipidemic and antioxidant influences as well as its remarkable anti-inflammatory and antiapoptotic properties.

Polydatin-loaded chitosan nanoparticles ameliorates early diabetic nephropathy by attenuating oxidative stress and inflammatory responses in streptozotocin-induced diabetic rat

In various developed countries, diabetic nephropathy (DN) is the principal cause of end-stage kidney disease and a main reason of injury and mortality in individuals with renal morbidity worldwide. Polydatin (POL) has been evaluated as a potential antioxidant, anti-inflammatory and a nephroprotective agent. In spite of this, the possible benefits and protective effects of POL on early diabetic nephropathy are not quite clarified. For the effective clearance from the body besides safe drug delivery, biodegradable nanoparticles have interesting attraction. This work was designed to evaluate the positive effect and possible mechanisms of Polydatin-loaded Chitosan-Nanoparticles (POL-NPs) on early DN in streptozotocin-induced diabetic rats. Followed the induction of diabetes, rats classified into four groups, diabetic control and diabetic rats treated daily and orally with; POL, Polydatin-loaded chitosan-Nanoparticles (POL-NPs), plus normal control rats. Our findings showed that diabetic group presented a significant high level of the blood glucose, blood glycosylated hemoglobin (HbA1c), serum insulin, renal function related parameters, renal Advanced glycation-end products (AGEs) and lipid peroxidation level compared to normal control rats, while serum albumin level and the activities of renal antioxidant enzymes were significantly decreased. Moreover, in the kidney of diabetic rat mRNA expression of nuclear factor-kappa B (NF-κB) and cyclooxygenase-2 (Cox-2) were up-regulated. Besides, increase in serum levels of pro-inflammatory cytokines (TNF-α, IL-6 and IL-18) and decrease in anti-inflammatory cytokine (IL-10). POL and POL-NPs supplementation were significantly attenuate the above-mention results and returned the normal equilibrium between pro- and anti-inflammatory cytokines. In conclusion, POL and POL-NPs have antidiabetic effect, suppresses oxidative stress and mitigates renal inflammation through inhibition of NF-κB in diabetic kidney in early progressive DN.

Protective effects of medicinal plant against diabetes induced cardiac disorder: A review

ETHNOPHARMACOLOGY RELEVANCE

Nowadays, there is an increase in global tendency to use medicinal plants as preventive and therapeutic agents to manage diabetes and its long-term complications such as cardiovascular disorders owing to their availability and valuable traditional background.

AIM OF STUDY

This review aims to introduce common medicinal plants, which have been demonstrated to have cardioprotective effects on diabetes and their mechanisms of action.

MATERIALS AND METHODS

Online literature databases, including Web of Sciences, PubMed, Science Direct, Scopus and Google Scholar were searched without date limitation by May 2020. The following keywords (natural products or medicinal plants or herbal medicine or herb or extract) and (diabetes or antidiabetic or hyperglycemic) and (cardiomyopathy or heart or cardioprotective or cardiac or cardio) were used, and after excluding non-relevant articles, 81 original English articles were selected.

RESULTS

The surveyed medicinal plants induced cardioprotective effects mostly through increasing antioxidant effects leading to attenuating ROS production as well as by inhibiting inflammatory signaling pathways and related cytokines. Moreover, they ameliorated the Na+/K + ATPase pump, the L-type Ca₂⁺ channel current, and the intracellular ATP. They also reduced cardiac remodeling and myocardial cell apoptosis through degradation of caspase-3, Bax, P53 protein, enhancement of Bcl-2 protein expression as well as downregulation of TGFβ1 and TNFα expression. In addition, the extracts improved cardiac function through increasing EF% and FS% as well as restoring hemodynamic parameters.

CONCLUSIONS

The reviewed medicinal plants demonstrated cardioprotective manifestations in diabetes through intervention with mechanisms involved in the diabetic heart to restore cardiovascular complications.

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.

Myricitrin, a Glycosyloxyflavone in Myrica esculenta Bark Ameliorates Diabetic Nephropathy via Improving Glycemic Status, Reducing Oxidative Stress, and Suppressing Inflammation

The present study evaluated the therapeutic potential of myricitrin (Myr), a glycosyloxyflavone extracted from Myrica esculenta bark, against diabetic nephropathy. Myr exhibited a significant hypoglycemic effect in high fat-fed and a single low-dose streptozotocin-induced type 2 diabetic (T2D) rats. Myr was found to improve glucose uptake by the skeletal muscle via activating IRS-1/PI3K/Akt/GLUT4 signaling in vitro and in vivo. Myr significantly attenuated high glucose (HG)-induced toxicity in NRK cells and in the kidneys of T2D rats. In this study, hyperglycemia caused nephrotoxicity via endorsing oxidative stress and inflammation resulting in the induction of apoptosis, fibrosis, and inflammatory damages. Myr was found to attenuate oxidative stress via scavenging/neutralizing oxidative radicals and improving endogenous redox defense through Nrf-2 activation in both in vitro and in vivo systems. Myr was also found to attenuate diabetes-triggered renal inflammation via suppressing NF-κB activation. Myr inhibited hyperglycemia-induced apoptosis and fibrosis in renal cells evidenced by the changes in the expressions of the apoptotic and fibrotic factors. The molecular docking predicted the interactions between Myr and different signal proteins. An in silico absorption, distribution, metabolism, excretion, and toxicity (ADMET) study predicted the drug-likeness character of Myr. Results suggested the possibility of Myr to be a potential therapeutic agent for diabetic nephropathy in the future.

Polydatin and polydatin-loaded chitosan nanoparticles attenuate diabetic cardiomyopathy in rats

Hyperglycemia is associated with impairment of heart function. The current study aimed to investigate the ameliorative effect of polydatin-loaded chitosan nanoparticles (PD-CSNPs), polydatin (PD) and metformin (MET) on diabetic cardiomyopathy in rats. Rats divided into six groups; normal-control, diabetic-control, diabetic + CSNPs (diabetic rats treated with 50 mg/kg blank chitosan nanoparticles), diabetic + PD-CSNPs (diabetic rats treated with PD-CSNPs equivalent to 50 mg/kg of polydatin), diabetic + PD (diabetic rats given 50 mg/kg polydatin), diabetic + MET (diabetic rats given 100 mg/kg metformin), orally and daily for 4 weeks. Treatment of diabetic rats with PD-CSNPs, PD and MET showed a significant reduction in the values of glucose and glycosylated hemoglobin with improvement in heart function biomarkers through decreasing serum creatine kinase and creatine kinase myocardial band activities compared to diabetic control. The treatment agents also suppressed the elevated lipid peroxidation product, increased values of glutathione content, superoxide dismutase, superoxide peroxidase, and catalase activities in the heart of diabetic treated rats. Furthermore, PD-CSNPs, PD and MET decreased heart tissue levels of a pro-inflammatory cytokine; tumor necrosis factor-alpha and nuclear factor-kappa β, upregulation of heart gene expressions; nuclear factor erythroid 2-related factor 2 and heme oxygenase-1. Histological and ultrastructural examinations revealed the ameliorative effect of PD-CSNPs, PD and MET against the harmful of diabetic cardiomyopathy by reducing the cardiac fibers, necrotic cardiac myocytes, inflammatory cell infiltration, and the arrangement of the myofibrils and intercalated discs. In conclusion, the new formula of PD-CSNPs was more effective than PD and MET in amelioration the diabetic cardiomyopathy through its antioxidant, anti-inflammatory and prolonged-release properties.

Value of peak strain dispersion in discovering left ventricular dysfunction in diabetes mellitus

Cardiovascular disease is one of the main causes of death in diabetes mellitus (DM) patients. The aim of the current study was to explore the value of peak strain dispersion (PSD) for discovering early-stage left ventricular (LV) dysfunction in type 2 diabetes mellitus (T2DM) patients. One hundred and one T2DM patients and sixty healthy subjects were selected for this study. T2DM patients were further divided into controlled blood glucose (HbA1c < 7%, n = 46) and uncontrolled blood glucose (HbA1c ≥ 7%, n = 55) subgroups. All participants underwent conventional echocardiography and two-dimensional speckle-tracking echocardiography. Our results showed that an obvious difference was not observed in global longitudinal strain (GLS) between the controlled blood glucose group and the control group (− 20.34% vs − 21.22%, P = 0.068). Compared with the healthy controls, the uncontrolled blood glucose group showed an impaired GLS (− 18.62% vs − 21.22%, P < 0.001). Nevertheless, PSD was appreciably increased in the controlled blood glucose group (36.02 ms vs 32.48 ms, P = 0.01) and uncontrolled blood glucose group (57.51 ms vs 32.48 ms, P < 0.001). Multivariate linear regression analysis showed that HbA1c was closely related to PSD lesion in the LV in the T2DM group (β = 0.520, P < 0.001). PSD plays an important role in evaluating the coordination and synchronization of myocardial movement and provides a more accurate and sensitive index assessment of early LV systolic function in T2DM patients. In addition, HbA1c levels were related to LV dysfunction.

Effect and Mechanism of Ganoderma lucidum Spores on Alleviation of Diabetic Cardiomyopathy in a Pilot in vivo Study

BACKGROUND

Ganoderma lucidum spores (GLS) exhibit disease prevention properties, but no study has been carried out on the anti-diabetic cardiomyopathy property of GLS. The aim of this study was to evaluate the hyperglycemia-mediated cardiomyopathy protection and mechanisms of GLS in streptozotocin (STZ)induced diabetic rats.

METHODS

Male SD rats were randomly divided into three groups. Two groups were given STZ (50 mg/kg, i.p.) treatment and when their fasting plasma glucose was above 16.7 mmol/L, among them, one group was given placebo, as diabetic group, and another group was given GLS (300 mg/kg) treatment. The group without STZ treatment was given placebo as a control group. The experiment lasted 70 days. The histology of myocardium and biomarkers of antioxidants, myocardial injury, pro-inflammatory cytokines, pro-apoptotic proteins and phosphorylation of key proteins in PI3K/AKT pathway were assessed.

RESULTS

Biochemical analysis showed that GLS treatment significantly reduced the blood glucose (-20.3%) and triglyceride (-20.4%) levels compared to diabetic group without treatment. GLS treatment decreased the content of MDA (-25.6%) and activity of lactate dehydrogenase (-18.9%) but increased the activity of GSH-Px (65.4%). Western blot analysis showed that GLS treatment reduced the expression of both alpha-smooth muscle actin and brain natriuretic peptide. Histological analysis on the cardiac tissue micrographs showed that GLS treatment reduced collagen fibrosis and glycogen reactivity in myocardium. Both Western blot and immunohistochemistry analyses showed that GLS treatment decreased the expression levels of pro-inflammatory factors (cytokines IL-1β, and TNF-α) as well as apoptosis regulatory proteins (Bax, caspase-3 and -9), but increased Bcl-2. Moreover, GLS treatment significantly increased the phosphorylation of key proteins involved in PI3K/AKT pathway, eg, p-AKT p-PI3K and mTOR.

CONCLUSION

The results indicated that GLS treatment alleviates diabetic cardiomyopathy by reducing hyperglycemia, oxidative stress, inflammation, apoptosis and further attenuating the fibrosis and myocardial dysfunction induced by STZ through stimulation of the PI3K/Akt/mTOR signaling pathway.

Pathophysiology, Clinical Characteristics of Diabetic Cardiomyopathy: Therapeutic Potential of Natural Polyphenols

Diabetic cardiomyopathy (DCM) is an outcome of disturbances in metabolic activities through oxidative stress, local inflammation, and fibrosis, as well as a prime cause of fatality worldwide. Cardiovascular disorders in diabetic individuals have become a challenge in diagnosis and formulation of treatment prototype. It is necessary to have a better understanding of cellular pathophysiology that reveal the therapeutic targets and prevent the progression of cardiovascular diseases due to hyperglycemia. Critical changes in levels of collagen and integrin have been observed in the extracellular matrix of heart, which was responsible for cardiac remodeling in diabetic patients. This review explored the understanding of the mechanisms of how the phytochemicals provide cardioprotection under diabetes along with the caveats and provide future perspectives on these agents as prototypes for the development of drugs for managing DCM. Thus, here we summarized the effect of various plant extracts and natural polyphenols tested in preclinical and cell culture models of diabetic cardiomyopathy. Further, the potential use of selected polyphenols that improved the therapeutic efficacy against diabetic cardiomyopathy is also illustrated.

Amygdalin alleviates renal injury by suppressing inflammation, oxidative stress and fibrosis in streptozotocin-induced diabetic rats

AIMS

To explore the protective efficacies and potent mechanism of amygdalin on high glucose-cultured renal cell HBZY-1 in vitro and streptozotocin (STZ)-induced diabetic nephropathy (DN) rat in vivo.

MAIN METHODS

The cellar proliferation and generation of ROS in high-glucose cultured HBZY-1 cell were assessed by MTT and DCFH-DA assay, respectively. The fasting blood glucose levels, renal function and inflammation indexes as well as oxidative stress markers in STZ-induced diabetic rats were all measured. The histologic renal section was stained with Mason and periodic acid-Schiff (PAS) method. Immunohistochemistry and western blotting methods were applied to assess expression levels of extracellular matrix (ECM), epithelial-mesenchymal transition (EMT)-related as well as TGF-β1/Smad signaling pathway-related proteins.

KEY FINDINGS

Firstly, amygdalin significantly suppressed the excessive cell proliferation and ROS generation in HBZY-1 cells cultured with high glucose. The hyperglycemia, 24 h-UP excretion, BUN and Scr of DN rats were significantly attenuated after the chronic treatment of amygdalin. Moreover, MDA, SOD, IFN-γ and IL-12 levels in kidney tissues were all effectively reduced. Besides, amygdalin can suppress the ECM accumulation and EMT transformation by inhibiting Smad/TGF-β pathway to alleviate the renal fibrosis in renal tissues of DN model rats.

SIGNIFICANCE

Amygdalin ameliorates excessive oxidative stress, inflammation and renal tissue fibrosis of DN mainly by suppressing TGF-β1/Smad signaling pathway and regulating the key enzymes of ECM degradation.

Apigenin-Loaded Solid Lipid Nanoparticle Attenuates Diabetic Nephropathy Induced by Streptozotocin Nicotinamide Through Nrf2/HO-1/NF-kB Signalling Pathway

Background

Apigenin is known to have a broad-spectrum efficacy in oxidative stress and conditions due to inflammation, although weak absorption, fast metabolic rate and a fast elimination (systemic) limit the pharmacological efficacy of this drug. Hence, we propose the usage of highly bioavailable Apigenin-solid lipid nanoparticles (SLNPs) to recognize such limitations. The defensive function of Apigenin-SLNPs on renal damage induced by streptozotocin (STZ) in animals was studied.

Materials and Methods

We initially injected the rats with 35 mg kg⁻¹ streptozocin intraperitoneally, and after 7 days, the rats were then injected 150 mg kg⁻¹ of metformin intragastrically followed by a once-daily intragastric dose of Apigenin-SLNP (25 or 50 mg kg⁻¹) for a continuous period of 30 days. We then measured the level of insulin and blood glucose, superoxide dismutase, catalase and malondialdehyde in the tissues of the kidney. We also observed messenger-RNA expression of Interleukin-1β, Interleukin-6 and Tumor Necrosis Factor-alpha in renal tissue through RT-PCR technique. Moreover, H&E staining and Western blotting observed the histopathological variations and protein expression of nuclear factor erythroid 2-related factor 2/heme oxygenase/Nuclear Factor-κB signaling pathway, respectively.

Results

An enhancement in the expressing of nuclear factor erythroid 2-related factor 2 and heme oxygenase-1 and a suppression in the expression of Nuclear Factor-κB occurred due to Apigenin-SLNPs treatment, which was a result of the protective mechanism of Apigenin-SLNPs which is because of not only its anti-inflammatory function (by inhibition of release of inflammatory factors) but also their anti-oxidant activity (through reduction of lipid peroxidation production).

Conclusion

We found that a protective effect on diabetic nephropathy was shown due to Apigenin-SLNPs, in rats induced with streptozocin maybe through the pathway of nuclear factor erythroid 2-related factor 2/heme oxygenase-1/Nuclear Factor-κB.

The Great Healing Potential Hidden in Plant Preparations of Antioxidant Properties: A Return to Nature?

The application of chemicals in industry and agriculture has contributed to environmental pollution and exposure of living organisms to harmful factors. The development of new pharmaceutical agents enabled successful therapy of various diseases, but their administration may be connected with side effects. Oxidative stress has been found to be involved into etiology of numerous diseases as well as harmful action of drugs and chemicals. For some time, plant origin substances have been studied as potential protective agents alleviating toxicity of various substances and symptoms of diseases. The aim of the current review was to present the diversity of the research performed during the last five years on animal models. The outcomes showed a huge protective potential inherent in plant preparations, including alleviating prooxidative processes, strengthening antioxidant defence, ameliorating immune parameters, and reversing histopathological changes. In many cases, plant origin substances were proved to be comparable or even better than standard drugs. Such findings let us suggest that in the future the plant preparations could make adjuvants or a replacement for pharmaceutical agents. However, the detailed research regarding dose and way of administration as well as the per se effects needs to be performed. In many studies, the last issue was not studied, and in some cases, the deleterious effects have been observed.

Metabolic regulation of endothelial SK channels and human coronary microvascular function

BACKGROUND

Diabetic (DM) inactivation of small conductance calcium-activated potassium (SK) channels contributes to coronary endothelial dysfunction. However, the mechanisms responsible for this down-regulation of endothelial SK channels are poorly understood. Thus, we hypothesized that the altered metabolic signaling in diabetes regulates endothelial SK channels and human coronary microvascular function.

METHODS

Human atrial tissue, coronary arterioles and coronary artery endothelial cells (HCAECs) obtained from DM and non-diabetic (ND) patients (n = 12/group) undergoing cardiac surgery were used to analyze metabolic alterations, endothelial SK channel function, coronary microvascular reactivity and SK gene/protein expression/localization.

RESULTS

The relaxation response of DM coronary arterioles to the selective SK channel activator SKA-31 and calcium ionophore A23187 was significantly decreased compared to that of ND arterioles (p < 0.05). Diabetes increases the level of NADH and the NADH/NAD+ ratio in human myocardium and HCAECs (p < 0.05). Increase in intracellular NADH (100 μM) in the HCAECs caused a significant decrease in endothelial SK channel currents (p < 0.05), whereas, intracellular application of NAD+ (500 μM) increased the endothelial SK channel currents (p < 0.05). Mitochondrial reactive oxygen species (mROS) of HCAECs and NADPH oxidase (NOX) and PKC protein expression in the human myocardium and coronary microvasculature were increased respectively (p < 0.05).

CONCLUSIONS

Diabetes is associated with metabolic changes in the human myocardium, coronary microvasculature and HCAECs. Endothelial SK channel function is regulated by the metabolite pyridine nucleotides, NADH and NAD+, suggesting that metabolic regulation of endothelial SK channels may contribute to coronary endothelial dysfunction in the DM patients with diabetes.

Diabetic cardiomyopathy: molecular mechanisms, detrimental effects of conventional treatment, and beneficial effects of natural therapy

ABSTARCT

Diabetic complications are among the largely exigent health problems currently. Cardiovascular complications, including diabetic cardiomyopathy (DCM), account for more than 80% of diabetic deaths. Investigators are exploring new therapeutic targets to slow or abate diabetes because of the growing occurrence and augmented risk of deaths due to its complications. Research on rodent models of type 1 and type 2 diabetes mellitus, and the use of genetic engineering techniques in mice and rats have significantly sophisticated for our understanding of the molecular mechanisms in human DCM. DCM is featured by pathophysiological mechanisms that are hyperglycemia, insulin resistance, oxidative stress, left ventricular hypertrophy, damaged left ventricular systolic and diastolic functions, myocardial fibrosis, endothelial dysfunction, myocyte cell death, autophagy, and endoplasmic reticulum stress. A number of molecular and cellular pathways, such as cardiac ubiquitin proteasome system, FoxO transcription factors, hexosamine biosynthetic pathway, polyol pathway, protein kinase C signaling, NF-κB signaling, peroxisome proliferator-activated receptor signaling, Nrf2 pathway, mitogen-activated protein kinase pathway, and micro RNAs, play a major role in DCM. Currently, there are a few drugs for the management of DCM and some of them have considerable adverse effects. So, researchers are focusing on the natural products to ameliorate it. Hence, in this review, we discuss the pathogical, molecular, and cellular mechanisms of DCM; the current diagnostic methods and treatments; adverse effects of conventional treatment; and beneficial effects of natural product-based therapeutics, which may pave the way to new treatment strategies. Graphical Abstract.

Green synthesis of silver nanoparticles by Nigella sativa extract alleviates diabetic neuropathy through anti-inflammatory and antioxidant effects

Green synthesis of silver nanoparticles has gained great interest among scientists. In view of this data, we conducted this study to identify the ameliorative effect of green synthesis of silver nanoparticles using Nigella sativa extract in diabetic neuropathy induced experimentally. In this study, 50 adult male albino rats were used and they were randomly divided into five groups; the first group was the healthy control group, the second group were the diabetic neuropathy diabetic neuropathy induced, Groups (3-6) diabetic neuropathy induced group and treated with silver nanoparticles, Nigella sativa extract and green synthesized silver nanoparticles using Nigella sativa extract respectively. Biochemical parameters including diabetic, inflammatory and antioxidant biomarkers were evaluated. Brain histopathology was also performed. Results revealed substantial rise in glucose, AGE, aldose reductase with insulin reduction in diabetic neuropathy induced group as compared to healthy control. Also, inflammatory markers increased significantly in diabetic neuropathy induced group. A remarkable change in oxidative status was observed in the same group. Furthermore, significant decline in nitrotyrosin level was observed. Regarding gene expression, we found significant down regulation in brain TKr A accompanied by upregulation of nerve growth factor in diabetic neuropathy group comparing with healthy control. Several treatments for diabetic neuropathy remarkably ameliorate all the investigated biomarkers. Histological findings are greatly relied on for the results achieved in this study. Therefore, it can be established that green synthesis of silver nanoparticles in combination with Nigella sativa extract could be a newly neuroprotective agents against inflammation and oxidative stress characterizing diabetic neuropathy through their antidiabetic, anti-inflammatory and anti-oxidants effects.

Methanolic Bark Extract of Abroma augusta (L.) Induces Apoptosis in EAC Cells through Altered Expression of Apoptosis Regulatory Genes

Abroma augusta (L.), one of the herbal medicinal plants, is widely used for treatment of various maladies. The present study was initiated to determine the antioxidant, hemolytic, cytotoxicity, and anticancer activities of methanolic extract from the bark of the plant. The phytochemical screening was done by analyzing different phytochemicals present in the extract. We observed the presence of alkaloids, steroids, terpenoids, flavonoids, reducing sugars, and glycosides in the bark extract which showed the highest antioxidant capacity. Antioxidant potential of the methanolic extract was evaluated in vitro by DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging assay method. This extract showed prominent scavenging activity with IC₅₀ value of 38.65 μg/ml. The hemolytic activity of the extract was evaluated at concentrations ranging from 250 to 1000 μg/ml. It was observed that the extract induced hemolysis percentage of 9.41% to 4.1%, which implies that the extract has no potent hemolytic activity. Cytotoxicity and anticancer activities were observed on Ehrlich ascites carcinoma (EAC) cells. In addition, the bark showed promising cytotoxicity with IC₅₀ value of 329.41 μg/ml, and the study indicated that the extract was capable of inhibiting EAC cell growth by 75.5% when administered at 100 mg/kg/day body weight intraperitoneally for five consecutive days to Swiss albino mice. Morphological change of apoptotic cell was determined by fluorescence and optical microscopy. DNA fragmentation is another marker for apoptosis, and the bark extract-treated EAC cells showed smeared and fragmented DNA bands. Apoptosis correlated well with the upregulation of p53 and Bax and also with the downregulation of NF-κB and Bcl-2. Furthermore, activity and interaction of two A. augusta compounds were tested through molecular docking simulation study. In conclusion, our results suggest that A. augusta bark has the potential to be considered as an anticancer agent.