Curcumin alleviates aristolochic acid nephropathy based on SIRT1/Nrf2/HO-1 signaling pathway

Agrimol B alleviates cisplatin-induced acute kidney injury by activating the Sirt1/Nrf2 signaling pathway in mice

Cisplatin (CDDP) is a widely used chemotherapeutic agent that has remarkable antineoplastic effects. However, CDDP can cause severe acute kidney injury (AKI), which limits its clinical application. Agrimol B is the main active ingredient found in Agrimonia pilosa Ledeb and has a variety of pharmacological activities. The effect of agrimol B on CDDP-induced renal toxicity has not been determined. To investigate whether agrimol B has a protective effect against CDDP-induced AKI, we first identify Sirtuin 1 (Sirt1) as a critical target protein of agrimol B in regulating AKI through network pharmacology analysis. Subsequently, the AKI mouse model is induced by administering a single dose of CDDP via intraperitoneal injection. By detecting the serum urea nitrogen and creatinine levels, as well as the histopathological changes, we confirm that agrimol B effectively reduces CDDP-induced AKI. In addition, treatment with agrimol B counteracts the increase in renal malondialdehyde level and the decrease in superoxide dismutase (SOD), catalase and glutathione levels induced by CDDP. Moreover, western blot results reveal that agrimol B upregulates the expressions of Sirt1, SOD2, nuclear factor erythroid2-related factor 2, and downstream molecules, including heme oxygenase 1 and NAD(P)H quinone dehydrogenase 1. However, administration of the Sirt1 inhibitor EX527 abolishes the effects of agrimol B. Finally, we establish a tumor-bearing mouse model and find that agrimol B has a synergistic antitumor effect with CDDP. Overall, agrimol B attenuates CDDP-induced AKI by activating the Sirt1/Nrf2 signaling pathway to counteract oxidative stress, suggesting that this compound is a potential therapeutic agent for the treatment of CDDP-induced AKI.

Sirtuins in kidney diseases: potential mechanism and therapeutic targets

Sirtuins, which are NAD+-dependent class III histone deacetylases, are involved in various biological processes, including DNA damage repair, immune inflammation, oxidative stress, mitochondrial homeostasis, autophagy, and apoptosis. Sirtuins are essential regulators of cellular function and organismal health. Increasing evidence suggests that the development of age-related diseases, including kidney diseases, is associated with aberrant expression of sirtuins, and that regulation of sirtuins expression and activity can effectively improve kidney function and delay the progression of kidney disease. In this review, we summarise current studies highlighting the role of sirtuins in renal diseases. First, we discuss sirtuin family members and their main mechanisms of action. We then outline the possible roles of sirtuins in various cell types in kidney diseases. Finally, we summarise the compounds that activate or inhibit sirtuin activity and that consequently ameliorate renal diseases. In conclusion, targeted modulation of sirtuins is a potential therapeutic strategy for kidney diseases. Video Abstract.

Therapeutic activity of green synthesized selenium nanoparticles from turmeric against cisplatin-induced oxido-inflammatory stress and cell death in mice kidney

Cisplatin (CDDP) is a commonly prescribed chemotherapeutic agent; however, its associated nephrotoxicity limits its clinical efficacy and sometimes requires discontinuation of its use. The existing study was designed to explore the reno-therapeutic efficacy of turmeric (Tur) alone or conjugated with selenium nanoparticles (Tur-SeNPs) against CDDP-mediated renal impairment in mice and the mechanisms underlying this effect. Mice were orally treated with Tur extract (200 mg/kg) or Tur-SeNPs (0.5 mg/kg) for 7 days after administration of a single dose of CDDP (5 mg/kg, i.p.). N-acetyl cysteine NAC (100 mg/kg) was used as a standard antioxidant compound. The results revealed that Tur-SeNPs counteracted CDDP-mediated serious renal effects in treated mice. Compared with the controls, Tur or Tur-SeNPs therapy remarkably decreased the kidney index along with the serum levels of urea, creatinine, Kim-1, and NGAL of the CDDP-injected mice. Furthermore, Tur-SeNPs ameliorated the renal oxidant status of CDDP group demonstrated by decreased MDA and NO levels along with elevated levels of SOD, CAT, GPx, GR, GSH, and gene expression levels of HO-1. Noteworthy, lessening of renal inflammation was exerted by Tur-SeNPs via lessening of IL-6 and TNF-α besides down-regulation of NF-κB gene expression in mouse kidneys. Tur-SeNPs treatment also restored the renal histological features attained by CDDP challenge and hindered renal apoptosis through decreasing the Bax levels and increasing Bcl-2 levels. Altogether, these outcomes suggest that the administration of Tur conjugated with SeNPs is effective neoadjuvant chemotherapy to guard against the renal adverse effects that are associated with CDDP therapy.

Protein acetylation and related potential therapeutic strategies in kidney disease

Kidney disease can be caused by various internal and external factors that have led to a continual increase in global deaths. Current treatment methods can alleviate but do not markedly prevent disease development. Further research on kidney disease has revealed the crucial function of epigenetics, especially acetylation, in the pathology and physiology of the kidney. Histone acetyltransferases (HATs), histone deacetylases (HDACs), and acetyllysine readers jointly regulate acetylation, thus affecting kidney physiological homoeostasis. Recent studies have shown that acetylation improves mechanisms and pathways involved in various types of nephropathy. The discovery and application of novel inhibitors and activators have further confirmed the important role of acetylation. In this review, we provide insights into the physiological process of acetylation and summarise its specific mechanisms and potential therapeutic effects on renal pathology.

Therapeutic application of traditional Chinese medicine in kidney disease: Sirtuins as potential targets

Sirtuins are a family of NAD+ III-dependent histone deacetylases that consists of seven family members, Sirt1-Sirt7, which regulate various signalling pathways and are involved in many critical biological processes of kidney diseases. Traditional Chinese medicine (TCM), as an essential part of the global healthcare system, has multi-component and multi-pathway therapeutic characteristics and plays a role in preventing and controlling various diseases. Through ongoing collaboration with modern medicine, TCM has recently achieved many remarkable advancements in theoretical investigation, mechanistic research, and clinical applications related to kidney diseases. Therefore, a comprehensive and systematic summary of TCM that focuses on sirtuins as the intervention target for kidney diseases is necessary. This review introduces the relationship between abnormal sirtuins levels and common kidney diseases, such as diabetic kidney disease and acute kidney injury. Based on the standard biological processes, such as inflammation, oxidative stress, autophagy, mitochondrial homeostasis, and fibrosis, which are underlying kidney diseases, comprehensively describes the roles and regulatory effects of TCM targeting the sirtuins family in various kidney diseases.

An unprecedented free radical mechanism for the formation of DNA adducts by the carcinogenic N-sulfonated metabolite of aristolochic acids

The carcinogenicity of aristolochic acids (AAs) has been attributed mainly to the formation of stable DNA-aristolactam (DNA-AL) adducts by its reactive N-sulfonated metabolite N-sulfonatooxyaristolactam (N-OSO3--AL). The most accepted mechanism for such DNA-AL adduct formation is via the postulated but never unequivocally-confirmed aristolactam nitrenium ion. Here we found that both sulfate radical and two ALI-derived radicals (N-centered and C-centered spin isomers) were produced by N-OSO3--ALI, which were detected and unequivocally identified by complementary applications of ESR spin-trapping, HPLC-MS coupled with deuterium-exchange methods. Both the formation of the three radical species and DNA-ALI adducts can be significantly inhibited (up to 90%) by several well-known antioxidants, typical radical scavengers, and spin-trapping agents. Taken together, we propose that N-OSO3--ALI decomposes mainly via a new N-O bond homolysis rather than the previously proposed heterolysis pathway, yielding reactive sulfate and ALI-derived radicals, which are together and in concert responsible for forming DNA-ALI adducts. This study presents strong and direct evidence for the production of free radical intermediates during N-OSO3--ALI decomposition, providing an unprecedented free radical perspective and conceptual breakthrough, which can better explain and understand the molecular mechanism for the formation of DNA-AA adducts, the carcinogenicity of AAs and their potential prevention.

Natural products for kidney disease treatment: Focus on targeting mitochondrial dysfunction

The patients with kidney diseases are increasing rapidly all over the world. With the rich abundance of mitochondria, kidney is an organ with a high consumption of energy. Hence, renal failure is highly correlated with the breakup of mitochondrial homeostasis. However, the potential drugs targeting mitochondrial dysfunction are still in mystery. The natural products have the superiorities to explore the potential drugs regulating energy metabolism. However, their roles in targeting mitochondrial dysfunction in kidney diseases have not been extensively reviewed. Herein, we reviewed a series of natural products targeting mitochondrial oxidative stress, mitochondrial biogenesis, mitophagy, and mitochondrial dynamics. We found lots of them with great medicinal values in kidney disease. Our review provides a wide prospect for seeking the effective drugs targeting kidney diseases.

Therapeutic Potential of Phenolic Compounds in Medicinal Plants-Natural Health Products for Human Health

Phenolic compounds and flavonoids are potential substitutes for bioactive agents in pharmaceutical and medicinal sections to promote human health and prevent and cure different diseases. The most common flavonoids found in nature are anthocyanins, flavones, flavanones, flavonols, flavanonols, isoflavones, and other sub-classes. The impacts of plant flavonoids and other phenolics on human health promoting and diseases curing and preventing are antioxidant effects, antibacterial impacts, cardioprotective effects, anticancer impacts, immune system promoting, anti-inflammatory effects, and skin protective effects from UV radiation. This work aims to provide an overview of phenolic compounds and flavonoids as potential and important sources of pharmaceutical and medical application according to recently published studies, as well as some interesting directions for future research. The keyword searches for flavonoids, phenolics, isoflavones, tannins, coumarins, lignans, quinones, xanthones, curcuminoids, stilbenes, cucurmin, phenylethanoids, and secoiridoids medicinal plant were performed by using Web of Science, Scopus, Google scholar, and PubMed. Phenolic acids contain a carboxylic acid group in addition to the basic phenolic structure and are mainly divided into hydroxybenzoic and hydroxycinnamic acids. Hydroxybenzoic acids are based on a C6-C1 skeleton and are often found bound to small organic acids, glycosyl moieties, or cell structural components. Common hydroxybenzoic acids include gallic, syringic, protocatechuic, p-hydroxybenzoic, vanillic, gentistic, and salicylic acids. Hydroxycinnamic acids are based on a C6-C3 skeleton and are also often bound to other molecules such as quinic acid and glucose. The main hydroxycinnamic acids are caffeic, p-coumaric, ferulic, and sinapic acids.

Exploring the Neuroprotective Mechanism of Curcumin Inhibition of Intestinal Inflammation against Parkinson's Disease Based on the Gut-Brain Axis

Parkinson's disease (PD) is a chronic progressive neurodegenerative disease commonly seen in aged people, in which gastrointestinal dysfunction is the most common nonmotor symptom and the activation of the gut-brain axis by intestinal inflammation may contribute to the pathogenesis of PD. In a previous study, curcumin was considered neuroprotective in PD, and this neuroprotective mechanism may act by inhibiting intestinal inflammation. Therefore, the aim of this study was to evaluate the effect of curcumin on motor dysfunction and the loss of dopaminergic neurons in a PD mouse model, induced by N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) using open field test and pole test behavioral assessments and the immunofluorescence and Western blot methods. Moreover, the effects of curcumin on gastrointestinal dysfunction, gastric barrier function, pro-inflammatory cytokines, and the SIRT1/NRF2 pathway in intestinal tissues in a PD mouse model were assessed using fecal parameters and intestinal dynamics, immunofluorescence, ELISA, and Western blot. A motor impairment study of an MPTP-induced mouse group prior to treatment with curcumin had a lower total movement distance and a slow average speed, while there was no statistical difference in the curcumin group. After treatment with curcumin, the total movement distance and average speed improved, the tyrosine hydroxylase (TH) rate in the substantia nigra pars compacta (SNpc) and striatum were reduced, the pyroptosis of AIM2 and caspase-1 activations were inhibited, and intestinal inflammatory factors and intestinal inflammation were reduced. Curcumin improved gastrointestinal disorders and gastrointestinal barrier function in the MPTP-induced mice and reversed MPTP-induced motor dysfunction and dopaminergic neuron loss in mice. The above effects may be partly dependent on curcumin activation of the SIRT1/NRF2 pathway in the colon. This study provides a potential opportunity to develop new preventive measures and novel therapeutic approaches that could target the gut-brain axis in the context of PD and provide a new intervention in the treatment of Parkinson's disease.