Curcumin Ameliorates Diabetic Nephropathy by Suppressing NLRP3 Inflammasome Signaling

The regulatory effect and mechanism of traditional Chinese medicine on the renal inflammatory signal transduction pathways in diabetic kidney disease: A review

Inflammatory injury is a critical factor in the occurrence and development of diabetic kidney disease (DKD). Signal transduction pathways such as the nuclear factor kappa beta (NF-κB), mitogen-activated protein kinase (MAPK), NOD-like receptor protein 3, and Smads are important mechanisms of inflammatory kidney injury in DKD, and the NF-κB pathway plays a key role. The inflammatory factor network formed after activation of the NF-κB pathway connects different signaling pathways and exacerbates renal inflammatory damage. Many traditional Chinese medicine compounds, single agents, effective components and active ingredients can regulate the expression of key molecules in the signaling pathways associated with inflammatory injury, such as transforming growth factor-β activated kinase 1, NF-κB, p38MAPK, NOD-like receptor protein 3, and Smad7. These treatments have the characteristics of multiple targets and have multiple and overlapping effects, which can treat DKD kidney inflammation and injury through multiple mechanisms and apply the "holistic concept" of traditional Chinese medicine.

Exploring the role of NLRP3 inflammasome in diabetic nephropathy and the advancements in herbal therapeutics

Diabetic nephropathy (DN), a prevalent complication of diabetes mellitus (DM), is clinically marked by progressive proteinuria and a decline in glomerular filtration rate. The etiology and pathogenesis of DN encompass a spectrum of factors, including hemodynamic alterations, inflammation, and oxidative stress, yet remain incompletely understood. The NOD-like receptor pyrin domain-containing 3 (NLRP3) inflammasome, a critical component of the body's innate immunity, plays a pivotal role in the pathophysiology of DN by promoting the release of inflammatory cytokines, thus contributing to the progression of this chronic inflammatory condition. Recent studies highlight the involvement of the NLRP3 inflammasome in the renal pathology associated with DN. This article delves into the activation pathways of the NLRP3 inflammasome and its pathogenic implications in DN. Additionally, it reviews the therapeutic potential of traditional Chinese medicine (TCM) in modulating the NLRP3 inflammasome, aiming to provide comprehensive insights into the pathogenesis of DN and the current advancements in TCM interventions targeting NLRP3 inflammatory vesicles. Such insights are expected to lay the groundwork for further exploration into TCM-based treatments for DN.

Research Progress of Pyroptosis in Diabetic Kidney Disease

Pyroptosis, known as one typical mode of programmed cell death, is generally characterized by the cleaved gasdermin family (GSDMs) forming pores in the cell membrane and inducing cell rupture, and the activation of aspartate-specific proteases (caspases) has also been found during this process. Diabetic Kidney Disease (DKD) is caused by the complication of diabetes in the kidney, and the most important kidney's function, Glomerular Filtration Rate (GFR), happens to drop to less than 90% of its usual and even lead to kidney failure in severe cases. The persistent inflammatory state induced by high blood glucose implies the key pathology of DKD, and growing evidence shows that pyroptosis serves as a significant contributor to this chronic immune-mediated inflammatory disorder. Currently, the expanded discovery of GSDMs, pyroptosis, and its association with innate immunity has been more attractive, and overwhelming research is needed to sort out the implication of pyroptosis in DKD pathology. In this review, we comb both classical studies and newly founds on pyroptosis, prick off the novel awakening of pyroptosis in DKD, and center on the significance of pyroptosis in DKD treatment, aiming to provide new research targets and treatment strategies on DKD.

Mechanisms and efficacy of traditional Chinese herb monomers in diabetic kidney disease

Diabetic kidney disease (DKD) is a serious complication of diabetes and is the primary cause of end-stage renal disease. Current treatment strategies primarily focus on the inhibition of the renin-angiotensin-aldosterone system and the attainment of blood glucose control. Although current medical therapies for DKD have been shown to delay disease progression and improve long-term outcomes, their efficacy is limited and they may be restricted in certain cases, particularly when hyperkalemia is present. Traditional Chinese medicine (TCM) treatment has emerged as a significant complementary approach for DKD. TCM monomers, derived from various Chinese herbs, have been found to modulate multiple therapeutic targets and exhibit a broad range of therapeutic effects in patients with DKD. This review aims to summarize the mechanisms of action of TCM monomers in the treatment of DKD, based on findings from clinical trials, as well as cell and animal studies. The results of these investigations demonstrate the potential effective use of TCM monomers in treating or preventing DKD, offering a promising new direction for future research in the field. By providing a comprehensive overview of the mechanisms and efficacy of TCM monomers in DKD, this review highlights the potential of these natural compounds as alternative therapeutic options for improving outcomes in patients with DKD.

To Explore the Putative Molecular Targets of Diabetic Nephropathy and their Inhibition Utilizing Potential Phytocompounds

BACKGROUND

This review critically addresses the putative molecular targets of Diabetic Nephropathy (DN) and screens effective phytocompounds that can be therapeutically beneficial, and highlights their mechanistic modalities of action.

INTRODUCTION

DN has become one of the most prevalent complications of clinical hyperglycemia, with individual-specific variations in the disease spectrum that leads to fatal consequences. Diverse etiologies involving oxidative and nitrosative stress, activation of polyol pathway, inflammasome formation, Extracellular Matrix (ECM) modifications, fibrosis, and change in dynamics of podocyte functional and mesangial cell proliferation adds up to the clinical complexity of DN. Current synthetic therapeutics lacks target-specific approach, and is associated with the development of inevitable residual toxicity and drug resistance. Phytocompounds provides a vast diversity of novel compounds that can become an alternative therapeutic approach to combat the DN.

METHODS

Relevant publications were searched and screened from research databases like GOOGLE SCHOLAR, PUBMED and SCISEARCH. Out of 4895 publications, the most relevant publications were selected and included in this article.

RESULT

This study critically reviews over 60 most promising phytochemical and provides with their molecular targets, that can be of pharmacological significance in context to current treatment and concomitant research in DN.

CONCLUSION

This review highlights those most promising phytocompounds that have the potential of becoming new safer naturally-sourced therapeutic candidates and demands further attention at clinical level.

Unveiling the Anti-Cholera and Active Diabetic Renoprotective Compounds of Maqian Essential Oil: A Computational and Molecular Dynamics Study

Cholera is an exceptionally aggressive infectious disease characterized by the potential to induce acute, copious, watery diarrhea of considerable severity and renal inflammation. Diabetic nephropathy is a serious complication of diabetes mellitus that can lead to kidney failure through inflammation; thus, anti-inflammatory agents are promising therapies for diabetic nephropathy. Previous studies have shown that the essential oil of Zanthoxylum myriacanthum var. pubescens Huang, Maqian essential oil (MQEO), exhibits potent antibacterial, anti-inflammatory, and renoprotective activities in diabetic mice and has emerged as a potential therapeutic drug for the treatment of diabetic nephropathy complications. Therefore, the present study was carried out to screen the potential inhibition of cholera toxin and the diabetic renoprotective activity of MQEO through computational approaches. Twelve chemical constituents derived from MQEO were docked with cholera toxin and the target proteins involved in diabetic nephropathy, namely, TXNIP, Nrf2, and DPP IV, and, subsequently, the predictions of molecular dynamic simulations, the drug-likeness properties, and the ADMET properties were performed. α-terpineol showed high binding affinities toward the cholera toxin protein. For TXNIP, among all the chemical constituents, α-phellandrene and p-cymene showed strong binding affinities with the TXNIP protein and displayed relatively stable flexibility at the hinge regions of the protein, favorable physicochemical properties in the absence of hepatotoxicity, and low cytotoxicity. For Nrf2, α-terpineol exhibited the highest binding affinity and formed a very stable complex with Nrf2, which displayed high pharmacokinetic properties. All compounds had low free-binding energies when docked with the DPP IV protein, which suggests potent biological activity. In conclusion, based on a computational approach, our findings reveal that MQEO constituents have inhibitory activity against cholera toxin and are promising therapeutic agents for suppressing diabetic inflammation and for the treatment of diabetic nephropathy complications.

The food and biomedical applications of curcumin-loaded electrospun nanofibers: A comprehensive review

Encapsulating curcumin (CUR) in nanocarriers such as liposomes, polymeric micelles, silica nanoparticles, protein-based nanocarriers, solid lipid nanoparticles, and nanocrystals could be efficient for a variety of industrial and biomedical applications. Nanofibers containing CUR represent a stable polymer-drug carrier with excellent surface-to-volume ratios for loading and cell interactions, tailored porosity for controlled CUR release, and diverse properties that fit the requirements for numerous applications. Despite the mentioned benefits, electrospinning is not capable of producing fibers from multiple polymers and biopolymers, and the product's effectiveness might be affected by various machine- and material-dependent parameters like the voltage and the flow rate of the electrospinning process. This review delves into the current and innovative recent research on nanofibers containing CUR and their various applications.

Broadening horizons: the contribution of mitochondria-associated endoplasmic reticulum membrane (MAM) dysfunction in diabetic kidney disease

Diabetic kidney disease (DKD) is a global health issue that presents a complex pathogenesis and limited treatment options. To provide guidance for precise therapies, it is crucial to accurately identify the pathogenesis of DKD. Several studies have recognized that mitochondrial and endoplasmic reticulum (ER) dysfunction are key drivers of the pathogenesis of DKD. The mitochondria-associated ER membrane (MAM) is a dynamic membrane contact site (MSC) that connects the ER and mitochondria and is essential in maintaining the normal function of the two organelles. MAM is involved in various cellular processes, including lipid synthesis and transport, calcium homeostasis, mitochondrial fusion and fission, and ER stress. Meanwhile, recent studies confirm that MAM plays a significant role in the pathogenesis of DKD by regulating glucose metabolism, lipid metabolism, inflammation, ER stress, mitochondrial fission and fusion, and autophagy. Herein, this review aims to provide a comprehensive summary of the physiological function of MAMs and their impact on the progression of DKD. Subsequently, we discuss the trend of pharmaceutical studies that target MAM resident proteins for treating DKD. Furthermore, we also explore the future development prospects of MAM in DKD research, thereby providing a new perspective for basic studies and clinical treatment of DKD.

Natural products in attenuating renal inflammation via inhibiting the NLRP3 inflammasome in diabetic kidney disease

Diabetic kidney disease (DKD) is a prevalent and severe complications of diabetes and serves as the primary cause of end-stage kidney disease (ESKD) globally. Increasing evidence indicates that renal inflammation is critical in the pathogenesis of DKD. The nucleotide - binding oligomerization domain (NOD) - like receptor family pyrin domain containing 3 (NLRP3) inflammasome is the most extensively researched inflammasome complex and is considered a crucial regulator in the pathogenesis of DKD. The activation of NLRP3 inflammasome is regulated by various signaling pathways, including NF- κB, thioredoxin-interacting protein (TXNIP), and non-coding RNAs (ncRNA), among others. Natural products are chemicals extracted from living organisms in nature, and they typically possess pharmacological and biological activities. They are invaluable sources for drug design and development. Research has demonstrated that many natural products can alleviate DKD by targeting the NLRP3 inflammasome. In this review, we highlight the role of the NLRP3 inflammasome in DKD, and the pathways by which natural products fight against DKD via inhibiting the NLRP3 inflammasome activation, so as to provide novel insights for the treatment of DKD.

Overview of Curcumin and Piperine Effects on Glucose Metabolism: The Case of an Insulinoma Patient’s Loss of Consciousness

The hypoglycemic properties of curcumin supplements in therapeutic doses are well-known and may represent a useful tool for the treatment of chronic diseases such as metabolic syndrome, insulin resistance and type 2 diabetes. The poor bioavailability of curcumin can be improved with the concomitant administration of piperine, with no severe adverse effects on glycemia reported so far in the literature. In this article, we further discuss a previously reported case of a helicopter pilot, affected by grade I obesity who, under curcumin and piperine treatment, experienced a transient loss of consciousness (TLOC), during a low-altitude flight. This episode led to a diagnosis of insulinoma, previously asymptomatic. We hypothesized that the combined effects of curcumin and piperine might have caused a severe hypoglycemic episode and subsequent TLOC. Therefore, further studies should be conducted to evaluate the safety of curcumin and piperine supplementation in subjects with impaired glucose metabolism and insulin secretion.

Effectiveness of targeting the NLRP3 inflammasome by using natural polyphenols: A systematic review of implications on health effects

Globally, inflammation and metabolic disorders pose serious public health problems and are major health concerns. It has been shown that natural polyphenols are effective in the treatment of metabolic diseases, including anti-inflammation, anti-diabetes, anti-obesity, neuron-protection, and cardio-protection. NLRP3 inflammasome, which are multiprotein complexes located within the cytosol, play an important role in the innate immune system. However, aberrant activation of the NLRP3 inflammasome were discovered as essential molecular mechanisms in triggering inflammatory processes as well as implicating it in several major metabolic diseases, such as type 2 diabetes mellitus, obesity, atherosclerosis or cardiovascular disease. Recent studies indicate that natural polyphenols can inhibit NLRP3 inflammasome activation. In this review, the progress of natural polyphenols preventing inflammation and metabolic disorders via targeting NLRP3 inflammasome is systemically summarized. From the viewpoint of interfering NLRP3 inflammasome activation, the health effects of natural polyphenols are explained. Recent advances in other beneficial effects, clinical trials, and nano-delivery systems for targeting NLRP3 inflammasome are also reviewed. NLRP3 inflammasome is targeted by natural polyphenols to exert multiple health effects, which broadens the understanding of polyphenol mechanisms and provides valuable guidance to new researchers in this field.

The Mitochondrion: A Promising Target for Kidney Disease

Mitochondrial dysfunction is important in the pathogenesis of various kidney diseases and the mitochondria potentially serve as therapeutic targets necessitating further investigation. Alterations in mitochondrial biogenesis, imbalance between fusion and fission processes leading to mitochondrial fragmentation, oxidative stress, release of cytochrome c and mitochondrial DNA resulting in apoptosis, mitophagy, and defects in energy metabolism are the key pathophysiological mechanisms underlying the role of mitochondrial dysfunction in kidney diseases. Currently, various strategies target the mitochondria to improve kidney function and kidney treatment. The agents used in these strategies can be classified as biogenesis activators, fission inhibitors, antioxidants, mPTP inhibitors, and agents which enhance mitophagy and cardiolipin-protective drugs. Several glucose-lowering drugs, such as glucagon-like peptide-1 receptor agonists (GLP-1-RA) and sodium glucose co-transporter-2 (SGLT-2) inhibitors are also known to have influences on these mechanisms. In this review, we delineate the role of mitochondrial dysfunction in kidney disease, the current mitochondria-targeting treatment options affecting the kidneys and the future role of mitochondria in kidney pathology.

Grape seed proanthocyanidin extract targets p66Shc to regulate mitochondrial biogenesis and dynamics in diabetic kidney disease

Mitochondrial biogenesis and dynamics are associated with renal mitochondrial dysfunction and the pathophysiological development of diabetic kidney disease (DKD). Decreased p66Shc expression prevents DKD progression by significantly regulating mitochondrial function. Grape seed proanthocyanidin extract (GSPE) is a potential therapeutic medicine for multiple kinds of diseases. The effect of GSPE on the mitochondrial function and p66Shc in DKD has not been elucidated. Hence, we decided to identify p66Shc as a therapeutic target candidate to probe whether GSPE has a renal protective effect in DKD and explored the underlying mechanisms.

METHODS

In vivo, rats were intraperitoneally injected with streptozotocin (STZ) and treated with GSPE. Biochemical changes, mitochondrial morphology, the ultrastructure of nephrons, and protein expression of mitochondrial biogenesis (SIRT1, PGC-1α, NRF1, TFAM) and dynamics (DRP1, MFN1) were determined. In vitro, HK-2 cells were transfected with p66Shc and treated with GSPE to evaluate changes in cell apoptosis, reactive oxygen species (ROS), mitochondrial quality, the protein expression.

RESULTS

In vivo, GSPE significantly improved the renal function of rats, with less proteinuria and a lower apoptosis rate in the injured renal tissue. Besides, GSPE treatment increased SIRT1, PGC-1α, NRF1, TFAM, and MFN1 expression, decreased p66Shc and DRP1 expression. In vitro, overexpression of p66Shc decreased the resistance of HK-2 cells to high glucose toxicity, as shown by increased apoptosis and ROS production, decreased mitochondrial quality and mitochondrial biogenesis, and disturbed mitochondrial dynamic homeostasis, ultimately leading to mitochondrial dysfunction. While GSPE treatment reduced p66Shc expression and reversed these changes.

CONCLUSION

GSPE can maintain the balance between mitochondrial biogenesis and dynamics by negatively regulating p66Shc expression.

Therapeutic mechanism and clinical application of Chinese herbal medicine against diabetic kidney disease

Diabetic kidney disease (DKD) is the major complications of type 1 and 2 diabetes, and is the predominant cause of chronic kidney disease and end-stage renal disease. The treatment of DKD normally consists of controlling blood glucose and improving kidney function. The blockade of renin-angiotensin-aldosterone system and the inhibition of sodium glucose cotransporter 2 (SGLT2) have become the first-line therapy of DKD, but such treatments have been difficult to effectively block continuous kidney function decline, eventually resulting in kidney failure and cardiovascular comorbidities. The complex mechanism of DKD highlights the importance of multiple therapeutic targets in treatment. Chinese herbal medicine (active compound, extract and formula) synergistically improves metabolism regulation, suppresses oxidative stress and inflammation, inhibits mitochondrial dysfunction, and regulates gut microbiota and related metabolism via modulating GLP-receptor, SGLT2, Sirt1/AMPK, AGE/RAGE, NF-κB, Nrf2, NLRP3, PGC-1α, and PINK1/Parkin pathways. Clinical trials prove the reliable evidences for Chinese herbal medicine against DKD, but more efforts are still needed to ensure the efficacy and safety of Chinese herbal medicine. Additionally, the ideal combined therapy of Chinese herbal medicine and conventional medicine normally yields more favorable benefits on DKD treatment, laying the foundation for novel strategies to treat DKD.

Aerobic exercise training alleviates renal injury in db/db mice through inhibiting Nox4-mediated NLRP3 inflammasome activation

Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease, with few therapeutic options available to slow its progression. Aerobic exercise training is an effective strategy for diabetes mellitus and its complications' prevention and treatment. The purpose of this study was to determine the effects of aerobic exercise training on diabetic kidney injury in db/db mice and to characterize the mechanism underlying the renal protective effects. The db/db mice were exercised 5 days a week for 60 min each day for 8 weeks at a speed of 5.6 m/min, after which renal function, morphology, oxidative stress, inflammation, fibrosis, and the expression of the Nox4/ROS/NF-κB/NLRP3 signaling pathway-related protein were assessed. Our results showed that aerobic exercise training significantly reduced body weight and microalbuminuria, improved renal function, and attenuated renal pathological changes in db/db mice independent of hyperglycemic state. Aerobic exercise training was also found to significantly improve oxidative stress and inflammation in the kidneys of db/db mice by decreasing the activity of complex I, the levels of MDA, 8-OHdG, Nox4, ROS, TNF-α, MCP-1, IL-6, and IL-18, increasing the activities of SOD and GSH-Px, the expression of klotho and NPHS2, and decreasing the phosphorylation of NF-κB p65 and IκBα, as well as the expression of NLRP3, ASC, caspase-1 p20, and IL-1β. Additionally, aerobic exercise training decreased TGF-β, collagen I, collagen IV, and α-SMA expression, thereby slowing the progression of kidney fibrosis in db/db mice. In conclusion, aerobic exercise training effectively reduces oxidative stress, inflammation, and renal fibrosis by modulating the Nox4/ROS/NF-κB/NLRP3 signaling pathway, implying that aerobic exercise training has significant potential to protect diabetic kidney injury and should be given more emphasis in DKD treatment.

An update on molecular mechanisms of curcumin effect on diabetes

Owing to its prevalent nature, diabetes mellitus has become one of the most serious endocrine illnesses affecting a patient's quality of life due to the manifestation of side effects such as cardiovascular diseases, retinopathy, neuropathy, and nephropathy. Curcumin ((1E, 6E) 21, 7-bis (4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione), a major compound of turmeric, has been used in conventional medicine because of its safe nature and cost-effectiveness to meliorate diabetes and its comorbidities. These effects have also been observed in rodent models of diabetes resulting in a reduction of glycemia and blood lipids. Both the preventive and therapeutic activities of this compound are due to its antioxidant and anti-inflammatory characteristics. Furthermore, preclinical outcomes and clinical investigation demonstrate that the use of curcumin neutralizes insulin resistance, obesity, and hyperglycemia. Despite the many benefits of curcumin, its two limiting factors, solubility and bioavailability, remain a challenge for researchers; therefore, several methods such as drug formulation, nano-drug delivery, and the use of curcumin analogs have been developed to deliver curcumin and increase its bioavailability. PRACTICAL APPLICATIONS: The rise of people with type 2 diabetes has become a major concern at the global healthcare level. The best diabetes treatments today are anti-diabetic drug administration, lifestyle-related interventions (such as healthy eating and daily physical activity), arterial pressure detection, and fat control. The polyphenol curcumin, found in turmeric, can promote health by acting on a variety of cellular signaling pathways. This review article discusses curcumin and its role in the treatment of diabetes.

A Glimpse of Inflammation and Anti-Inflammation Therapy in Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a common complication of diabetes mellitus and a major cause of end-stage kidney disease (ESKD). The pathogenesis of DKD is very complex and not completely understood. Recently, accumulated evidence from in vitro and in vivo studies has demonstrated that inflammation plays an important role in the pathogenesis and the development of DKD. It has been well known that a variety of pro-inflammatory cytokines and related signaling pathways are involved in the procession of DKD. Additionally, some anti-hyperglycemic agents and mineralocorticoid receptor antagonists (MRAs) that are effective in alleviating the progression of DKD have anti-inflammatory properties, which might have beneficial effects on delaying the progression of DKD. However, there is currently a lack of systematic overviews. In this review, we focus on the novel pro-inflammatory signaling pathways in the development of DKD, including the nuclear factor kappa B (NF-κB) signaling pathway, toll-like receptors (TLRs) and myeloid differentiation primary response 88 (TLRs/MyD88) signaling pathway, adenosine 5′-monophosphate-activated protein kinase (AMPK) signaling pathways, inflammasome activation, mitochondrial DNA (mtDNA) release as well as hypoxia-inducible factor-1(HIF-1) signaling pathway. We also discuss the related anti-inflammation mechanisms of metformin, finerenone, sodium-dependent glucose transporters 2 (SGLT2) inhibitors, Dipeptidyl peptidase-4 (DPP-4) inhibitors, Glucagon-like peptide-1 (GLP-1) receptor agonist and traditional Chinese medicines (TCM).

A Comprehensive Review on the Benefits and Problems of Curcumin with Respect to Human Health

Curcumin is the most important active component in turmeric extracts. Curcumin, a natural monomer from plants has received a considerable attention as a dietary supplement, exhibiting evident activity in a wide range of human pathological conditions. In general, curcumin is beneficial to human health, demonstrating pharmacological activities of anti-inflammation and antioxidation, as well as antitumor and immune regulation activities. Curcumin also presents therapeutic potential in neurodegenerative, cardiovascular and cerebrovascular diseases. In this review article, we summarize the advancements made in recent years with respect to curcumin as a biologically active agent in malignant tumors, Alzheimer’s disease (AD), hematological diseases and viral infectious diseases. We also focus on problems associated with curcumin from basic research to clinical translation, such as its low solubility, leading to poor bioavailability, as well as the controversy surrounding the association between curcumin purity and effect. Through a review and summary of the clinical research on curcumin and case reports of adverse effects, we found that the clinical transformation of curcumin is not successful, and excessive intake of curcumin may have adverse effects on the kidneys, heart, liver, blood and immune system, which leads us to warn that curcumin has a long way to go from basic research to application transformation.

Immunometabolic rewiring of tubular epithelial cells in kidney disease

Kidney tubular epithelial cells (TECs) have a crucial role in the damage and repair response to acute and chronic injury. To adequately respond to constant changes in the environment, TECs have considerable bioenergetic needs, which are supported by metabolic pathways. Although little is known about TEC metabolism, a number of ground-breaking studies have shown that defective glucose metabolism or fatty acid oxidation in the kidney has a key role in the response to kidney injury. Imbalanced use of these metabolic pathways can predispose TECs to apoptosis and dedifferentiation, and contribute to lipotoxicity and kidney injury. The accumulation of lipids and aberrant metabolic adaptations of TECs during kidney disease can also be driven by receptors of the innate immune system. Similar to their actions in innate immune cells, pattern recognition receptors regulate the metabolic rewiring of TECs, causing cellular dysfunction and lipid accumulation. TECs should therefore be considered a specialized cell type - like cells of the innate immune system - that is subject to regulation by immunometabolism. Targeting energy metabolism in TECs could represent a strategy for metabolically reprogramming the kidney and promoting kidney repair.

Insights into the Uses of Traditional Plants for Diabetes Nephropathy: A Review

Diabetic nephropathy (DN) is a serious kidney illness characterized by proteinuria, glomerular enlargement, reduced glomerular filtration, and renal fibrosis. DN is the most common cause of end-stage kidney disease, accounting for nearly one-third of all cases of diabetes worldwide. Hyperglycemia is a major factor in the onset and progression of diabetic nephropathy. Many contemporary medicines are derived from plants since they have therapeutic properties and are relatively free of adverse effects. Glycosides, alkaloids, terpenoids, and flavonoids are among the few chemical compounds found in plants that are utilized to treat diabetic nephropathy. The purpose of this review was to consolidate information on the clinical and pharmacological evidence supporting the use of a variety of medicinal plants to treat diabetic nephropathy.

The Prospective Ameliorative Role of Zinc Oxide Nanoparticles in STZ-Induced Diabetic Nephropathy in Rats: Mechanistic Targeting of Autophagy and Regulating Nrf2/TXNIP/NLRP3 Inflammasome Signaling

Diabetic nephropathy (DN) as one of the common microvascular complications of diabetes mellitus, is the main cause of end-stage renal disease. Zinc oxide nanoparticles (ZnO NPs) have been employed in several biomedical aspects. This study purposed to explore the mechanistic renoprotective effects of ZnO NPs in STZ-induced DN. Sixty male Wistar rats were allocated into four equal groups: control, ZnO NPs control, STZ, and STZ + ZnO NPs groups. At the end of the experiment, blood and urine biochemical parameters were assayed. Renal tissue level of advanced glycation end products (AGEs) was assayed spectrofluorometrically, moreover, nuclear factor erythroid 2-related factor 2 (Nrf2) DNA-binding activity and IL-1β levels were detected by ELISA. The gene expression levels of thioredoxin-interacting protein (TXNIP) and NOD-like receptor family pyrin domain containing 3 (NLRP3) were detected by quantitative real-time PCR. Oxidative stress markers were determined spectrophotometrically. Also, renal tissue histopathological and immunohistochemical analyses were determined. After 6 weeks of treatment, ZnO NPs markedly improved the biochemical, renal functions, and histopathological findings. Furthermore, ZnO NPs significantly increased Nrf2-DNA-binding activity and downregulated TXNIP gene expression leading to restoration of the redox status. Additionally, ZnO NPs ameliorated AGEs levels, enhanced autophagy activity, and attenuated inflammasome activation via downregulation of NLRP3 expression and reducing IL-1β levels. Based on our results, we concluded that ZnO NPs can be considered as a promising agent for slowing the progression of DN via interplay between autophagy and Nrf2/TXNIP/NLRP3 inflammasome signaling.

TLR9 regulates NLRP3 inflammasome activation via the NF-kB signaling pathway in diabetic nephropathy

BACKGROUND

Toll-like receptors (TLRs) are critical sensors for the conservation of bacterial molecules and play a key role in host defense against pathogens. The effect of TLRs on the maintenance of diabetic nephropathy (DN) and resistance to infection has been investigated; however, the detailed effects of TLR9 on DN development remain elusive.

METHODS

We performed quantitative reverse transcription-polymerase chain reaction and western blotting to detect TLR9 expression levels in the kidneys of experimental mice (db/db) and high-glucose-treated mouse mesangial cell strains (MCs).

RESULTS

TLR9 expression was found to be remarkably upregulated in the kidneys of experimental mice (db/db) and MCs cultivated under hyperglycemic conditions. Moreover, knockdown of TLR9 could restrain NF-kB viability and downregulate the NLRP3 inflammasome in high glucose-treated MCs. TLR9 inhibition also alleviated inflammation and apoptosis, which was reversed by the addition of the NF-κB activator, betulinic acid. Furthermore, depleted TLR9 levels restrained NF-κB viability and NLRP3 expression and reduced kidney inflammation, microalbuminuria discharge, blood sugar level, and glomerular damage in experimental mice (db/db) kidneys. Conclusions These findings offer novel insights into the regulation of TLR9 via the nuclear factor-kB/NOD-, LRR-, and pyrin domain-containing protein 3 inflammasome inflammation pathways in DN progression.

Curcumin Reverts the Protein Differential Expression in the Liver of the Diabetic Obese db/db Mice

Background:

In type 2 diabetic mouse liver, hyperglycemia, and insulin modify gene expression. Curcumin is a powerful antioxidant and antidiabetic agent that regulates the gene expression of different signaling pathways through various transcription factors. Therefore, we hypothesized that curcumin modifies the protein expression profile in the liver of diabetic db/db mice.

Objective:

To determine the effects of curcumin on the liver protein profile of diabetic db/db mice.

Methods:

db/db and wild type (WT) male mice were allocated in four groups, and they were fed for eight weeks. Three WT and three diabetic db/db mice received a standard diet (SD; WT and db/db groups, respectively); three WT and three diabetic db/db mice received a SD supplemented with 0.75 % (w/w) curcumin (WT+C and db/db+C groups, respectively). Liver proteins were separated by 2D electrophoresis. Differential protein expression analysis was performed on ImageMaster 2D Platinum software, and selected proteins were identified by MALDI-TOF-MS and subjected to enrichment analysis using STRING and DAVID databases.

Results:

Thirty-six proteins with differential expression due to the diabetic background and curcumin treatment were found; these proteins participate in the metabolism of amino acids, carbohydrates, and lipids. Interestingly, the altered expression of seven proteins was prevented in the liver of the diabetic mice that received curcumin.

Conclusions:

Among all differentially expressed proteins, curcumin reverted the altered expression of seven proteins. Thus, although it was observed that curcumin did not affect the biochemical parameters, it does modify the expression of some liver proteins in diabetic mice.

Renoprotective Roles of Curcumin

The use of herb-based therapies is increasing over the past decades. These agents have been reported to provide many beneficial effects in many experimental and clinical studies. Curcumin is one of these agents which has potent pharmacological effects enabling it for the prevent and treatment of many diseases and pathologies such as renal disorders, hyperglycemia, oxidative stress, hypertension, and dyslipidemia. However, the exact molecular mechanisms mediating these renoprotective effects of curcumin are not well established. So, in the current study, we surveyed for possible renoprotective roles of curcumin and concluded how curcumin protects against renal injuries.

Metabolic Dysfunction in the Regulation of the NLRP3 Inflammasome Activation: A Potential Target for Diabetic Nephropathy

Metabolic dysfunction plays a key role in the development of diabetic nephropathy (DN). However, the exact effects and mechanisms are still unclear. The pyrin domain-containing protein 3 (NLRP3) inflammasome, a member of the nod-like receptor family, is considered a crucial inflammatory regulator and plays important roles in the progress of DN. A growing body of evidence suggests that high glucose, high fat, or other metabolite disorders can abnormally activate the NLRP3 inflammasome. Thus, in this review, we discuss the potential function of abnormal metabolites such as saturated fatty acids (SFAs), cholesterol crystals, uric acid (UA), and homocysteine in the NLRP3 inflammasome activation and explain the potential function of metabolic dysfunction regulation of NLRP3 activation in the progress of DN via regulation of inflammatory response and renal interstitial fibrosis (RIF). In addition, the potential mechanisms of metabolism-related drugs, such as metformin and sodium glucose cotransporter (SGLT2) inhibitors, which have served as the suppressors of the NLRP3 inflammasomes, in DN, are also discussed. A better understanding of NLRP3 inflammasome activation in abnormal metabolic microenvironment may provide new insights for the prevention and treatment of DN.

The Potential Role of Curcumin in Modulating the Master Antioxidant Pathway in Diabetic Hypoxia-Induced Complications

Oxidative stress is the leading player in the onset and development of various diseases. The Keap1-Nrf2 pathway is a pivotal antioxidant system that preserves the cells' redox balance. It decreases inflammation in which the nuclear trans-localization of Nrf2 as a transcription factor promotes various antioxidant responses in cells. Through some other directions and regulatory proteins, this pathway plays a fundamental role in preventing several diseases and reducing their complications. Regulation of the Nrf2 pathway occurs on transcriptional and post-transcriptional levels, and these regulations play a significant role in its activity. There is a subtle correlation between the Nrf2 pathway and the pivotal signaling pathways, including PI3 kinase/AKT/mTOR, NF-κB and HIF-1 factors. This demonstrates its role in the development of various diseases. Curcumin is a yellow polyphenolic compound from Curcuma longa with multiple bioactivities, including antioxidant, anti-inflammatory, anti-tumor, and anti-viral activities. Since hyperglycemia and increased reactive oxygen species (ROS) are the leading causes of common diabetic complications, reducing the generation of ROS can be a fundamental approach to dealing with these complications. Curcumin can be considered a potential treatment option by creating an efficient therapeutic to counteract ROS and reduce its detrimental effects. This review discusses Nrf2 pathway regulation at different levels and its correlation with other important pathways and proteins in the cell involved in the progression of diabetic complications and targeting these pathways by curcumin.

Effect of Curcumin on Diabetic Kidney Disease: A Systematic Review and Meta-Analysis of Randomized, Double-Blind, Placebo-Controlled Clinical Trials

Background

Curcumin, a polyphenolic constituent from Curcuma longa, possesses antioxidant, hypolipidemic, and antidiabetic properties and has been reported to protect against diabetic kidney disease (DKD); however, the effect is inconsistent.

Objective

This systematic review and meta-analysis aimed to investigate the effect of curcumin supplementation on renal function, lipid profile, blood pressure, and glycemic control in DKD.

Methods

A systematic and comprehensive literature search of interrelated randomized controlled trials (RCTs) was conducted in PubMed, Embase, Cochrane Library, Web of Science, Scopus, and ClinicalTrials.gov from inception to July 30, 2021. Two investigators independently extracted data and assessed the risk of bias. Weighted mean differences (WMDs) with 95% confidence intervals (CIs) were calculated to describe the effect sizes using a fixed-effect model. Statistical analysis was performed using STATA 14.0 and RevMan 5.3.

Results

Five RCTs involving 290 participants with DKD were included. Curcumin supplementation significantly improved the serum creatinine (WMD: −0.16 mg/dL, 95% CI: −0.3 to −0.02, P = 0.029, I² = 0%, moderate certainty), total cholesterol (WMD: −10.13 mg/dL, 95% CI: −17.84 to −2.14, P = 0.01, I² = 0%, moderate certainty), systolic blood pressure (WMD: 3.94 mmHg, 95% CI: 1.86 to 6.01, P < 0.01, I² = 33.5%, moderate certainty), and fasting blood glucose (WMD: −8.29 mg/dL, 95% CI: −15.19 to −1.39, P = 0.019, I² = 43.7%, moderate certainty) levels; however, it had no significant effects on blood urea nitrogen, proteinuria, triglyceride, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, and diastolic blood pressure levels.

Conclusions

Curcumin may provide great potential effects against DKD. More large-scale and high-quality RCTs are required to confirm these findings.

Preparation of Curcumin Solid Lipid Nanoparticles Loaded with Flower-Shaped Lactose for Lung Inhalation and Preliminary Evaluation of Cytotoxicity In Vitro

The purpose of this study is to design a flower-shaped lactose loaded curcumin solid lipid nanoparticles dry powder inhaler and characterize it to improve the solubility and dissolution rate of curcumin in lung. Curcumin solid lipid nanoparticles (Cur-SLNs) were prepared by solvent evaporation method, and then they were micronized by freeze-drying technology. Finally, Cur-SLN micropowder obtained by freeze-drying was mixed with flower-shaped lactose (FL) at a ratio of 2 : 1 and then passed through a 200-mesh sieve to obtain Cur-SLN-FL powder. Tween-80 was selected as the surfactant to inhibit the aggregation of drug solid lipid nanoparticles. Under the optimum conditions, the solid lipid nanoparticles (SLN) were relatively spherical, with an average particle size of 14.7 nm, narrow distribution, Zeta potential of -22.5 mV, encapsulation efficiency of 90.21%, and drug loading of 8.56%. According to the particle size, PI, Zeta potential, drug loading (LC%), encapsulation efficiency (EE%), morphology, and in vitro release characteristics, the prescription of solid lipid nanoparticles was screened. Dry powder inhaler (DPI) was characterized by differential scanning calorimetry, scanning electron microscopy, particle size, density, and in vitro release performance. Its cytotoxicity to mouse fibroblasts (L929) and human normal lung epithelial cells (BEAS-2B) in vitro was investigated, and its safety for pulmonary inhalation was preliminarily determined. FTIR analysis shows that the micronized Cur-SLN-FL has the same chemical structure as FL. FTIR and DSC analysis confirmed that the characteristic absorption peak of curcumin was not found in Cur-SLN-FL, showing similar structure to SLN and FL. In addition, curcumin was coated in solid lipid nanoparticles to make powder mist, which increased its drug loading, kept its aerodynamic particle size (4.03 ± 0.40) μm, and significantly improved its drug release performance in artificial lung fluid. In vitro cytotoxicity test results confirmed that Cur-SLN-FL was less toxic to BEAS-2B cells than L929 cells. Therefore, curcumin was prepared into solid lipid nanoparticles by emulsion evaporation-low temperature solidification method and then micronized and mixed with FL to prepare curcumin solid lipid nanoparticle powder mist loaded with flower-shaped lactose. The process is simple and feasible, and it has better safety performance for lung cells, which is expected to become a safe and effective delivery system for pulmonary inhalation drugs.

Dietary natural products as a potential inhibitor towards advanced glycation end products and hyperglycemic complications: A phytotherapy approaches

Natural products exist in various natural foods such as plants, herbs, fruits, and vegetables. Furthermore, marine life offers potential natural products with significant biological activity. The biochemical reaction is known as advanced glycation end products (AGEs) occurs in the human body. On the other hand, foods are capable of a wide range of processing conditions resulting in the generation of exogenous AGEs adducts. Protein glycation and the formation of advanced glycation end products both contribute to the pathogenesis of hyperglycemic complications. AGEs also play a pivotal role in microvascular and macrovascular complications progression by receptors for advanced glycation end products (RAGE). RAGE activate by AGEs leads to up-regulation of transcriptional factor NF-kB and inflammatory genes. Around the globe, researchers are working in various approaches for therapeutical implications on controlling AGEs mediated disease complications. In this regard, one of the potential promising agents observed with a wide range of AGEs inhibition by food-derived natural products. Current biotechnological tools have been turned to natural products or phytochemicals to manufacture the molecules without compromising their functionality. Metabolic engineering and bioinformatics perspectives have recently enabled the generation of a few potent metabolites with anti-diabetic activity. As the primary focus, this review article will also discuss multidisciplinary approaches that emphasize current advances in anti-diabetic therapeutic action and future perspectives of natural products.

The Role of Mitochondria in Acute Kidney Injury and Chronic Kidney Disease and Its Therapeutic Potential

Mitochondria are heterogeneous and highly dynamic organelles, playing critical roles in adenosine triphosphate (ATP) synthesis, metabolic modulation, reactive oxygen species (ROS) generation, and cell differentiation and death. Mitochondrial dysfunction has been recognized as a contributor in many diseases. The kidney is an organ enriched in mitochondria and with high energy demand in the human body. Recent studies have been focusing on how mitochondrial dysfunction contributes to the pathogenesis of different forms of kidney diseases, including acute kidney injury (AKI) and chronic kidney disease (CKD). AKI has been linked to an increased risk of developing CKD. AKI and CKD have a broad clinical syndrome and a substantial impact on morbidity and mortality, encompassing various etiologies and representing important challenges for global public health.&nbsp;Renal mitochondrial disorders are a common feature of diverse forms of AKI and CKD, which result from defects in mitochondrial structure, dynamics, and biogenesis as well as crosstalk of mitochondria with other organelles. Persistent dysregulation of mitochondrial homeostasis in AKI and CKD affects diverse cellular pathways, leading to an increase in renal microvascular loss, oxidative stress, apoptosis, and eventually renal failure. It is important to understand the cellular and molecular events that govern mitochondria functions and pathophysiology in AKI and CKD, which should facilitate the development of novel therapeutic strategies. This review provides an overview of the molecular insights of the mitochondria and the specific pathogenic mechanisms of mitochondrial dysfunction in the progression of AKI, CKD, and AKI to CKD transition. We also discuss the possible beneficial effects of mitochondrial-targeted therapeutic agents for the treatment of mitochondrial dysfunction-mediated AKI and CKD, which may translate into therapeutic options to ameliorate renal injury and delay the progression of these kidney diseases.

Targeting NLRP3 Inflammasome in the Treatment Of Diabetes and Diabetic Complications: Role of Natural Compounds from Herbal Medicine

Diabetes, a common metabolic disease with various complications, is becoming a serious global health pandemic. So far there are many approaches in the management of diabetes; however, it still remains irreversible due to its complicated pathogenesis. Recent studies have revealed that nucleotide-binding and oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome plays a vital role in the progression of diabetes and many of its complications, making it a promising therapeutic target in pharmaceutical design. Natural derived herbal medicine, known for its utilization of natural products such as herbs or its bioactive ingredients, is shown to be able to ameliorate hyperglycemia-associated symptoms and to postpone the progression of diabetic complications due to its anti-inflammatory and anti-oxidative properties. In this review, we summarized the role of NLRP3 inflammasome in diabetes and several diabetic complications, as well as 31 active compounds that exert therapeutic effect on diabetic complications via inhibiting NLRP3 inflammasome. Improving our understanding of these promising candidates from natural compounds in herbal medicine targeting NLRP3 inflammasome inspires us the relationship between inflammation and metabolic disorders, and also sheds light on searching potential agents or therapies in the treatment of diabetes and diabetic complications.

Development of Biomarkers and Molecular Therapy Based on Inflammatory Genes in Diabetic Nephropathy

Diabetic Nephropathy (DN) is a debilitating consequence of both Type 1 and Type 2 diabetes affecting the kidney and renal tubules leading to End Stage Renal Disease (ESRD). As diabetes is a world epidemic and almost half of diabetic patients develop DN in their lifetime, a large group of people is affected. Due to the complex nature of the disease, current diagnosis and treatment are not adequate to halt disease progression or provide an effective cure. DN is now considered a manifestation of inflammation where inflammatory molecules regulate most of the renal physiology. Recent advances in genetics and genomic technology have identified numerous susceptibility genes that are associated with DN, many of which have inflammatory functions. Based on their role in DN, we will discuss the current aspects of developing biomarkers and molecular therapy for advancing precision medicine.

Pyroptosis in diabetic nephropathy

Diabetic nephropathy (DN), a sterile inflammatory disease, is a serious complication of diabetes mellitus. However, recent evidence indicates that pyroptosis, a new term for pro-inflammatory cell death featured by gasdermin D (GSDMD)-stimulated plasma membrane pore generation, cell expansion and rapid lysis with the extensive secretion of pro-inflammatory factors, including interleukin-1β (IL-1β) and -18 (IL-18) may be involved in DN. Caspase-1-induced canonical and caspase-4/5/11-induced non-canonical inflammasome-signaling pathways are mainly believed to participate in pyroptosis-mediated cell death. Further research has uncovered that activation of the caspase-3/8 signaling pathway may also activate pyroptosis. Accumulating evidence has shown that NLRP3 inflammasome activation plays a critical role in promoting the pathogenesis of DN. In addition, current studies have suggested that pyroptosis-induced cell death promotes several diabetic complications that include DN. Our present study briefs the cellular mechanisms of pyroptosis-related signaling pathways and their impact on the promotion of DN. In this review, several investigational compounds suppressing pyroptosis-mediated cell death are explored as promising therapeutics in DN.

Curcumin Antagonizes Glucose Fluctuation-Induced Renal Injury by Inhibiting Aerobic Glycolysis via the miR-489/LDHA Pathway

It has been considered that glucose fluctuation (GF) plays a role in renal injury and is related to diabetic nephropathy (DN) development. But the mechanism is still unclear. Aerobic glycolysis has become a topical issue in DN in recent years. There is an internal connection between GF, aerobic glycolysis, and DN. Curcumin (Cur) is a principal curcuminoid of turmeric and possesses specific protective properties in kidney functions. Cur also participates in the regulation of aerobic glycolysis switch. In this study, we first measured the levels of aerobic glycolysis and evaluated Cur's inhibitory ability in a cell model of HEK-293 under the condition of oscillating high glucose. The results indicated that GF exacerbated inflammation injury, oxidative stress, and apoptosis in HEK-293 cell, while Cur alleviated this cytotoxicity induced by GF. We found that GF increased aerobic glycolysis in HEK-293 cells and Cur presented a dose-dependent weakening effect to this exacerbation. Next, we built a panel of 17 miRNAs and 8 lncRNAs that were previously reported to mediate the Warburg effect. Our RT-qPCR results indicated that GF reduced the miR-489 content in the HEK-293 cell model and Cur could prevent this downregulation. Then, we planned to explore the character of miR-489 in Cur-triggered attenuation of the Warburg effect under GF condition. Our findings presented that Cur prevented GF-triggered aerobic glycolysis by upregulating miR-489 in HEK-293 cells. Next, we choose the miR-489/LDHA axis for further investigation. We confirmed that Cur prevented GF-triggered aerobic glycolysis via the miR-489/LDHA axis in HEK-293 cells. In conclusion, this study presented that Cur prevented GF-triggered renal injury by restraining aerobic glycolysis via the miR-489/LDHA axis in the HEK-293 cell model.

Protective Effect of Yi Shen Pai Du Formula against Diabetic Kidney Injury via Inhibition of Oxidative Stress, Inflammation, and Epithelial-to-Mesenchymal Transition in db/db Mice

OBJECTIVE

Diabetic kidney disease (DKD) is one of the most common chronic microvascular complications of diabetes; however, there remains a lack of effective therapeutic strategies. Yi Shen Pai Du Formula (YSPDF), a traditional Chinese medicine preparation, has been clinically used in treating chronic kidney disease (CKD) for more than 20 years. However, whether YSPDF has a therapeutic effect on DKD has not been studied.

METHODS

This study was conducted to investigate the effect of YSPDF administration on db/db mice, a model of type 2 diabetes that develops DKD, and reveal its underlying mechanism of action through a high glucose- (HG-) induced renal injury cell model.

RESULTS

We found that YSPDF significantly improved numerous biochemical parameters (fasting blood glucose, serum creatinine, blood urea nitrogen, 24 h urine total protein, total cholesterol, and total triglycerides) and ameliorated the abnormal histology and fibrosis of renal tissue. Moreover, the status of oxidative stress and levels of inflammatory cytokines (TNF-α, IL-6, IL-1β, and MCP-1) were markedly inhibited by YSPDF treatment. YSPDF treatment significantly mitigated renal fibrosis, with evidence suggesting that this was by inhibiting epithelial-to-mesenchymal transition (EMT) via suppression of the TGF-β1/Smad pathway. Interestingly, the expression of Nrf2, HO-1, and NQO1, proteins known to be associated with oxidative stress, were significantly increased upon administration of YSPDF. The levels of NLRP3 inflammasome proteins, including NLRP3, ASC, caspase-1, and cleaved caspase-1 were decreased in the YSPDF-treated group. Cell experiments showed that YSPDF inhibited EMT and the NLRP3 inflammasome in HG-exposed HK-2 cells, possibly via activation of Nrf2.

CONCLUSION

Our study indicates that YSPDF may ameliorate renal damage in db/db mice via inhibition of oxidative stress, inflammation, and EMT, with the mechanism potentially being related to the activation of the Nrf2 pathway.

Promise of the NLRP3 Inflammasome Inhibitors in In Vivo Disease Models

Nucleotide-binding oligomerization domain NOD-like receptors (NLRs) are conserved cytosolic pattern recognition receptors (PRRs) that track the intracellular milieu for the existence of infection, disease-causing microbes, as well as metabolic distresses. The NLRP3 inflammasome agglomerates are consequent to sensing a wide spectrum of pathogen-associated molecular patterns (PAMPs) and danger-associated molecular patterns (DAMPs). Certain members of the NLR family have been documented to lump into multimolecular conglomerates called inflammasomes, which are inherently linked to stimulation of the cysteine protease caspase-1. Following activation, caspase-1 severs the proinflammatory cytokines interleukin (IL)-1β and IL-18 to their biologically active forms, with consequent commencement of caspase-1-associated pyroptosis. This type of cell death by pyroptosis epitomizes a leading pathway of inflammation. Accumulating scientific documentation has recorded overstimulation of NLRP3 (NOD-like receptor protein 3) inflammasome involvement in a wide array of inflammatory conditions. IL-1β is an archetypic inflammatory cytokine implicated in multiple types of inflammatory maladies. Approaches to impede IL-1β's actions are possible, and their therapeutic effects have been clinically demonstrated; nevertheless, such strategies are associated with certain constraints. For instance, treatments that focus on systemically negating IL-1β (i.e., anakinra, rilonacept, and canakinumab) have been reported to result in an escalated peril of infections. Therefore, given the therapeutic promise of an NLRP3 inhibitor, the concerted escalated venture of the scientific sorority in the advancement of small molecules focusing on direct NLRP3 inflammasome inhibition is quite predictable.

Mitostasis, Calcium and Free Radicals in Health, Aging and Neurodegeneration

Mitochondria play key roles in ATP supply, calcium homeostasis, redox balance control and apoptosis, which in neurons are fundamental for neurotransmission and to allow synaptic plasticity. Their functional integrity is maintained by mitostasis, a process that involves mitochondrial transport, anchoring, fusion and fission processes regulated by different signaling pathways but mainly by the peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α). PGC-1α also favors Ca²⁺ homeostasis, reduces oxidative stress, modulates inflammatory processes and mobilizes mitochondria to where they are needed. To achieve their functions, mitochondria are tightly connected to the endoplasmic reticulum (ER) through specialized structures of the ER termed mitochondria-associated membranes (MAMs), which facilitate the communication between these two organelles mainly to aim Ca²⁺ buffering. Alterations in mitochondrial activity enhance reactive oxygen species (ROS) production, disturbing the physiological metabolism and causing cell damage. Furthermore, cytosolic Ca²⁺ overload results in an increase in mitochondrial Ca²⁺, resulting in mitochondrial dysfunction and the induction of mitochondrial permeability transition pore (mPTP) opening, leading to mitochondrial swelling and cell death through apoptosis as demonstrated in several neuropathologies. In summary, mitochondrial homeostasis is critical to maintain neuronal function; in fact, their regulation aims to improve neuronal viability and to protect against aging and neurodegenerative diseases.

NLRP3 Inflammasome in Metabolic-Associated Kidney Diseases: An Update

Metabolic syndrome (MS) is a group of complex metabolic disorders syndrome, which refers to the pathological state of metabolism disorder of protein, fat, carbohydrate and other substances in human body. The kidney is an important organ of metabolism, and various metabolic disorders can lead to the abnormalities in the structure and function of the kidney. The recognition of pathogenesis and treatment measures of renal damage in MS is a very important part for the renal function preserve. Inflammatory response caused by various metabolic factors is a protective mechanism of the body, but persistent inflammation will become a harmful factor and aggravate kidney damage. Inflammasomes are sensors of the innate immune system that play crucial roles in initiating inflammation in response to acute infections and chronic diseases. They are multiprotein complex composed of cytoplasmic sensors (mainly NLR family members), apoptosis-associated speck-like protein (ASC or PYCARD) and pro-caspase-1. After receiving exogenous and endogenous stimuli, the sensors begin to assemble inflammasome and then promote the release of inflammatory cytokines IL-1β and IL-18, resulting in a special way of cell death named pyroptosis. In the kidney, NLRP3 inflammasome can be activated by a variety of pathways, which eventually leads to inflammatory infiltration, renal intrinsic cell damage and renal function decline. This paper reviews the function and specific regulatory mechanism of inflammasome in kidney damage caused by various metabolic disorders, which will provide a new therapeutic perspective and targets for kidney diseases.

Medicinal plants and bioactive natural products as inhibitors of NLRP3 inflammasome

The NLR family, pyrin domain-containing 3 (NLRP3) inflammasome is a multiprotein complex that induces caspase-1 activation and the downstream substrates involved with the processing and secretion of the pro-inflammatory cytokines interleukin-1β (IL-1β) and IL-18 and tumor necrosis factor-α (TNF- α). The NLRP3 inflammasome is activated by a wide range of danger signals that derive from metabolic dysregulation. Activation of this complex often involves the adaptor ASC and upstream sensors including NLRP1, NLRP3, NLRC4, AIM2, and pyrin, which are activated by different stimuli including infectious agents and changes in cell homeostasis. It has been shown that nutraceuticals and medicinal plants have antiinflammatory properties and could be used as complementary therapy in the treatment of several chronic diseases that are related to inflammation, for example, cardiovascular diseases and diabetes mellitus. Herb-based medicine has demonstrated protective effects against NLRP3 inflammasome activation. Therefore, this review focuses on the effects of nutraceuticals and bioactive compounds derived from medicinal plants on NLRP3 inflammasome activation and the possible mechanisms of action of these natural products. Thus, herb-based, natural products/compounds can be considered novel, practical, and accessible agents in chronic inflammatory diseases by inhibiting NLRP3 inflammasome activation.

Liraglutide-induced structural modulation of the gut microbiota in patients with type 2 diabetes mellitus

Accumulating evidence has suggested the importance of gut microbiota in the development of type 2 diabetes mellitus (T2DM). In the present study, 40 patients with T2DM were treated with liraglutide for 4 months. Feces samples and clinical characteristics were collected from these 40 T2DM patients before and after the liraglutide treatment. The diversity and composition of gut microbiota in the two groups were determined by sequencing the V4 region of bacterial 16S rRNA genes. Meanwhile, blood glucose, insulin, hemoglobin A1c (HbA1c), and lipid metabolism were also measured in the pre- and post-liraglutide-treatment groups. We find that Baseline HbA1c was associated with liraglutide treatment response (R₂ = 0.527, β =  − 0.726, p < 0.0001). After adjusted for baseline HbA1c, blood urea nitrogen was associated with liraglutide treatment response. Besides, our results showed reduced gut microbial alpha diversity, different community structure distribution and altered microbial interaction network in patients treated with liraglutide. The liner discriminant analysis (LDA) effect size (LEfSe) analysis showed that 21 species of bacteria were abundant in the pre-liraglutide-treatment group and 15 species were abundant in the post-liraglutide-treatment group. In addition, we also find that Megamonas were significantly correlated with older age, diabetes duration and diabetic retinopathy, Clostridum were significantly correlated with family history of diabetes and Oscillospira were significantly correlated with both diabetic retinopathy and diabetic peripheral neuropathy. Functional analysis based on Kyoto Encyclopedia of Genes and Genomes (KEGG) and cluster of orthologous groups (COG) annotations enriched three KEGG metabolic pathways and six functional COG categories in the post-liraglutide-treatment group. In conclusion, our research suggests that baseline HbA1c, blood urea nitrogen and gut microbiota are associated with the liraglutide treatment applied on patients with T2DM. These findings may contribute to the beneficial effects of liraglutide against diabetes.

Curcumin attenuates renal interstitial fibrosis by regulating autophagy and retaining mitochondrial function in unilateral ureteral obstruction rats

Renal interstitial fibrosis (RIF) is the leading cause of end-stage renal disease, partly because of the lack of effective treatments. Curcumin, the primary active ingredient in turmeric, reportedly exerts potent antifibrotic effects. This study investigated the effects of curcumin on RIF in unilateral ureteral obstruction (UUO) rats and characterized the underlying action mechanism. UUO rats were treated with curcumin for 7 and 14 d. Renal fibrosis was evaluated through haematoxylin-eosin staining, Masson staining, and type I and III collagen expression. Autophagy and mitochondria were observed through scanning electron microscopy. NLRP3 inflammasomes, mitochondria, and autophagy-related proteins were detected through Western blotting. Mitochondrial respiratory enzyme activity was assessed spectrophotometrically. Compared with UUO rats, renal fibrosis was attenuated and NLRP3 inflammasome activation was inhibited in curcumin-treated rats. Furthermore, mitochondrial dysfunction was ameliorated and the LC3B/LC3A ratio and Beclin-1 expression were increased in curcumin-treated rats. Additionally, curcumin inhibited the PI3K/AKT/mTOR pathway. These results indicate that curcumin is a promising treatment agent for RIF, and its antifibrotic effects may be mediated by the inhibition of NLRP3 inflammasome activity through the regulation of autophagy and protection of mitochondrial function in UUO rats.

Protective Role of Nrf2 in Renal Disease

Chronic kidney disease (CKD) is one of the fastest-growing causes of death and is predicted to become by 2040 the fifth global cause of death. CKD is characterized by increased oxidative stress and chronic inflammation. However, therapies to slow or prevent CKD progression remain an unmet need. Nrf2 (nuclear factor erythroid 2-related factor 2) is a transcription factor that plays a key role in protection against oxidative stress and regulation of the inflammatory response. Consequently, the use of compounds targeting Nrf2 has generated growing interest for nephrologists. Pre-clinical and clinical studies have demonstrated that Nrf2-inducing strategies prevent CKD progression and protect from acute kidney injury (AKI). In this article, we review current knowledge on the protective mechanisms mediated by Nrf2 against kidney injury, novel therapeutic strategies to induce Nrf2 activation, and the status of ongoing clinical trials targeting Nrf2 in renal diseases.

Nutraceutical Strategies for Suppressing NLRP3 Inflammasome Activation: Pertinence to the Management of COVID-19 and Beyond

Inflammasomes are intracellular protein complexes that form in response to a variety of stress signals and that serve to catalyze the proteolytic conversion of pro-interleukin-1β and pro-interleukin-18 to active interleukin-1β and interleukin-18, central mediators of the inflammatory response; inflammasomes can also promote a type of cell death known as pyroptosis. The NLRP3 inflammasome has received the most study and plays an important pathogenic role in a vast range of pathologies associated with inflammation-including atherosclerosis, myocardial infarction, the complications of diabetes, neurological and autoimmune disorders, dry macular degeneration, gout, and the cytokine storm phase of COVID-19. A consideration of the molecular biology underlying inflammasome priming and activation enables the prediction that a range of nutraceuticals may have clinical potential for suppressing inflammasome activity-antioxidants including phycocyanobilin, phase 2 inducers, melatonin, and N-acetylcysteine, the AMPK activator berberine, glucosamine, zinc, and various nutraceuticals that support generation of hydrogen sulfide. Complex nutraceuticals or functional foods featuring a number of these agents may find utility in the prevention and control of a wide range of medical disorders.

Therapeutic application of nutraceuticals in diabetic nephropathy: Current evidence and future implications

Diabetes mellitus (DM) is a common metabolic disease which may cause several complications, such as diabetic nephropathy (DN). The routine medical treatments used for DM are not effective enough and have many undesirable side effects. Moreover, the global increased prevalence of DM makes researchers try to explore potential complementary or alternative treatments. Nutraceuticals, as natural products with pharmaceutical agents, have a wide range of therapeutic properties in various pathologic conditions such as DN. However, the exact underlying mechanisms have not been fully understood. The purpose of this review is to summarize recent findings on the effect of nutraceuticals on DN.

Inhibitory effects of phytochemicals on NLRP3 inflammasome activation: A review

BACKGROUND

The NLRP3 inflammasome formation and following cytokine secretion is a crucial step in innate immune responses. Internal and external factors may trigger inflammasome activation and result in inflammatory cytokine secretion. Inflammasome formation and activity play critical roles in several disease pathologies such as cardiovascular, metabolic, renal, digestive, and CNS diseases. Underlying pathways are not yet clear, but phytochemicals as alternative therapies have been extensively used for suppression of inflammatory responses.

PURPOSE

In this review, we aimed to summarize in vivo and in vitro effects on NLRP3 inflammasome activation of selected phytochemicals.

METHOD

Three phytochemicals; Sulforaphane, Curcumin, and Resveratrol were selected, and studies were reviewed to clarify their intracellular signaling mechanism in NLRP3 inflammasome activity. PubMed and Scopus databases are used for the search. For sulforaphane, 8 articles, for curcumin, 25 articles, and for resveratrol, 41 articles were included in the review.

CONCLUSION

In vitro and in vivo studies pointed out that the selected phytochemicals have inhibitory properties on NLRP3 inflammasome activity. However, neither the mechanism is clear, nor the study designs and doses are standardized.

IMPACTS OF COVID-19 ON THE IMMUNE, NEUROMUSCULAR, AND MUSCULOSKELETAL SYSTEMS AND REHABILITATION

ABSTRACT The new coronavirus, which causes the infectious disease named COVID-19 by the World Health Organization (WHO), was notified in 2020 in China. The main clinical manifestations in infected patients are fever, cough and dyspnoea. These patients are prone to developing cardiac changes, diffuse myopathy, decreased pulmonary function, decreased inspiratory muscle strength, and a deterioration in functional capacity. Thus, it is expected that patients affected by COVID-19 will suffer musculoskeletal consequences as a result of the inflammatory process and loss of muscle mass caused by immobility, generating motor incapacities that are not yet quantifiable. It is important to understand the clinical implications caused by COVID-19, in order to have better rehabilitation strategies for these patients. The aim of this study was to conduct a reflective analysis of the impact of COVID-19 on the immune, neuromuscular and musculoskeletal systems, and its rehabilitation process. This is a reflexive analysis, developed in the Laboratory for the Study of Movement of the Institute of Orthopaedics’ and Traumatology, at the Universidade de São Paulo School of Medicine, SP, Brazil. In this analysis, we reflect on the following topics related to COVID-19: immunological mechanisms, impact on the neuromuscular and musculoskeletal systems, and the rehabilitation of patients. Level of evidence V; Opinion of the specialist.

Ameliorative role of curcumin on copper oxide nanoparticles-mediated renal toxicity in rats: An investigation of molecular mechanisms

The increasing role of copper oxide nanoparticles (CuO NPs) in many industries and their broad range of applications increase its potential toxic effects. Curcumin possesses a wide range of health benefits. This study aimed to evaluate the role of curcumin in attenuating CuO NPs toxicity in rat kidney. Thirty six animals were divided into five groups; control groups (I, II), curcumin group orally received curcumin 200 mg/kg bw, CuO NPs group orally gavaged 250 mg/kg bw CuO NPs and combined group orally gavaged curcumin and CuO NPs. Treatment was given for 3 months. Administration of CuO NPs revealed elevation in serum creatinine and blood urea nitrogen levels, elevated kidney and urine levels of kidney injury molecule-1, decreased catalase, superoxide dismutase activities, total sulfhydryl, reduced glutathione content, increased serum reactive oxygen species, tissue total oxidant status, lipid hydroperoxides, protein carbonyl, malondialdehyde, nitric oxide levels, increased interleukin-1β, tumor necrosis factor-α, nuclear factor (NF-κB), and decreased heme oxygenase-1 (HO-1) and γ-glutamylcysteine synthetase (γ-GCS) genes expression. Moreover, histopathological alteration in kidney structure was detected. Immunohistochemical-stained sections by caspase-3 reaction revealed apoptosis. Pretreatment with curcumin improved most of the adverse effects in rats treated with CuO NPs regarding oxidative stress and inflammatory indices in kidney, and kept histopathological- and immunohistochemical-stained sections near to normal. This study shows that curcumin administration attenuates the toxicity in the kidney of CuO NPs-treated rats through its antioxidant, anti-inflammatory, and antiapoptotic effects.