Eleutheroside B Protects against Acute Kidney Injury by Activating IGF Pathway

Insulin-like growth factor-1 effects on kidney development in preterm piglets

BACKGROUND

Preterm birth disrupts fetal kidney development, potentially leading to postnatal acute kidney injury. Preterm infants are deficient in insulin-like growth factor 1 (IGF-1), a growth factor that stimulates organ development. By utilizing a preterm pig model, this study investigated whether IGF-1 supplementation enhances preterm kidney maturation.

METHODS

Cesarean-delivered preterm pigs were treated systemically IGF-1 or vehicle control for 5, 9 or 19 days after birth. Blood, urine, and kidney tissue were collected for biochemical, histological and gene expression analyses. Age-matched term-born pigs were sacrificed at similar postnatal ages and served as the reference group.

RESULTS

Compared with term pigs, preterm pigs exhibited impaired kidney maturation, as indicated by analyses of renal morphology, histopathology, and inflammatory and injury markers. Supplementation with IGF-1 reduced signs of kidney immaturity, particularly in the first week of life, as indicated by improved morphology, upregulated expression of key developmental genes, reduced severity and incidence of microscopic lesions, and decreased levels of inflammatory and injury markers. No association was seen between the symptoms of necrotizing enterocolitis and kidney defects.

CONCLUSION

Preterm birth in pigs impairs kidney maturation and exogenous IGF-1 treatment partially reverses this impairment. Early IGF-1 supplementation could support the development of preterm kidneys.

IMPACT

Preterm birth may disrupt kidney development in newborns, potentially leading to morphological changes, injury, and inflammation. Preterm pigs have previously been used as models for preterm infants, but not for kidney development. IGF-1 supplementation promotes kidney maturation and alleviates renal impairments in the first week of life in preterm pigs. IGF-1 may hold potential as a supportive therapy for preterm infants sensitive to acute kidney injury.

Madecassoside alleviates acute kidney injury by regulating JNK-mediated oxidative stress and programmed cell death

BACKGROUND

Acute kidney injury (AKI) has high morbidity and mortality, which is manifested by inflammation and apoptosis. Effective treatment methods for AKI are currently lacking.

OBJECTIVE

This study demonstrated the protecting effects of Madecassoside (MA) in the cisplatin- and hypoxia-reoxygenation-induced renal tubular epithelial cells in vitro and AKI mice in vivo.

METHODS

In vivo AKI mouse models were established by inducing them with cisplatin and renal ischemia-reperfusion. In vitro injury models of mouse renal tubular epithelial cells were established by inducing them with cisplatin and hypoxia and reoxygenation, respectively. The mechanism of MA effects was further explored using molecular docking and RNA-sequencing.

RESULTS

MA could significantly reduce kidney injury in the cisplatin-and renal ischemia-reperfusion (IRI)-induced AKI. Further validation in the two cellular models also showed that MA had protect effects. MA can alleviate AKI in vitro and in vivo by inhibiting inflammation, cell apoptosis, and oxidative stress. MA exhibited high permeability across the Caco-2 cell, can enter cells directly. Through RNA-seq and molecular docking analysis, this study further demonstrated that MA inhibits its activity by directly binding to JNK kinase, thereby inhibiting c-JUN mediated cell apoptosis and improving AKI. In addition, MA has better renal protective effects compared to curcumin and JNK inhibitor SP600125.

CONCLUSION

The results demonstrate that MA might be a potential drug for the treatment of AKI and act through the JNK/c-JUN signaling pathway.

Umbelliferone attenuates cisplatin-induced acute kidney injury by inhibiting oxidative stress and inflammation via NRF2

In this study, we investigated the nephroprotective effects of Umbelliferone (UMB) against cisplatin-induced acute kidney injury (AKI). C57BL/6J mice were treated with cisplatin via a single intraperitoneal injection (25 mg/kg) with or without UMB (40 mg/kg/day) by gavage. Renal function, apoptosis, oxidative stress, inflammation, and mitochondrial function were analyzed to evaluate kidney injury. In vitro, human proximal tubule epithelial cells were treated with cisplatin, with or without UMB, for 24 h. Western blotting and immunohistochemistry were performed to explore the mechanisms underlying the nephroprotective effects of UMB. Cisplatin-induced renal dysfunction, including increases in blood urea nitrogen, serum creatinine, and renal tubular injury indices (NGAL and KIM-1), were significantly attenuated by UMB treatment, along with renal phenotypic changes and renal tubular injury, as evidenced by improved renal histology. Moreover, NRF2 was activated by UMB pretreatment, along with the inhibition of oxidative stress and inflammatory response, as evidenced by decreased levels of antioxidant genes and inflammatory cytokines in cisplatin-induced AKI. Our results demonstrate that UMB can protect against cisplatin-induced nephrotoxicity, which is mediated by the NRF2 signaling pathway via antioxidant and anti-inflammatory activities, suggesting the clinical potential of UMB for the treatment of AKI.

The underlying mechanisms of cisplatin-induced nephrotoxicity and its therapeutic intervention using natural compounds

Cisplatin is an effective chemotherapeutic drug widely used for the treatment of various solid tumors; however, its clinical use and efficacy are limited by its inherent nephrotoxicity. The pathogenesis of cisplatin-induced nephrotoxicity is complex and has not been fully elucidated. Cellular uptake and transport, DNA damage, apoptosis, oxidative stress, inflammatory response, and autophagy are involved in the development of cisplatin-induced nephrotoxicity. Currently, despite some deficiencies, hydration regimens remain the major protective measures against cisplatin-induced nephrotoxicity. Therefore, effective drugs must be explored and developed to prevent and treat cisplatin-induced kidney injury. In recent years, many natural compounds with high efficiency and low toxicity have been identified for the treatment of cisplatin-induced nephrotoxicity, including quercetin, saikosaponin D, berberine, resveratrol, and curcumin. These natural agents have multiple targets, multiple effects, and low drug resistance; therefore, they can be safely used as a supplementary regimen or combination therapy for cisplatin-induced nephrotoxicity. This review aimed to comprehensively describe the molecular mechanisms underlying cisplatin-induced nephrotoxicity and summarize natural kidney-protecting compounds to provide new ideas for the development of better therapeutic agents.

Alleviation of temporomandibular joint osteoarthritis by targeting RIPK1-mediated inflammatory signalling

Temporomandibular joint osteoarthritis (TMJOA), prevalent in adolescents and the elderly, has serious physical and psychological consequences. TMJOA is a degenerative disease of the cartilage and bone, mostly driven by inflammation, and synoviocytes are the first and most important inflammatory factor releasers. Receptor-interacting serine/threonine-protein kinase (RIPK1) promotes inflammatory response and cell death during an array of illnesses. This research aimed to explore the impacts of RIPK1 inhibitor therapy in TMJOA and the mechanism of RIPK1 in inducing inflammation during TMJOA. Herein, inhibition of RIPK1 suppressed the elevated levels of inflammatory factors, nuclear factor kappa B (NF-κB), along with markers of apoptosis and necroptosis after tumour necrosis factor (TNF)-α/cycloheximide (CHX) treatment in synoviocytes. Moreover, inflammation models were constructed in vivo through complete Freund's adjuvant (CFA) induction and disc perforation, and the findings supported that RIPK1 inhibition protected TMJ articular cartilage against progressive degradation. RIPK1 regulates NF-κB activation via cellular inhibitor of apoptosis proteins (cIAP), apoptosis via caspase-8, and necroptosis via RIPK3/mixed lineage kinase domain-like (MLKL) in synoviocytes, which in turn facilitates TMJOA inflammation progression.

Discovery of a chalcone derivative as potent necroptosis inhibitor for the treatment of acute kidney injury

Necroptosis, a form of inflammation-related programmed cell death, is a major mechanism of proximal tubular cell injury in acute kidney injury (AKI). Blockade of necroptosis signaling represents a promising strategy for clinical therapy of AKI. Previously, we identified a small molecular RIPK1 inhibitor Cpd-71 with nephroprotective activities. In order to discover more nephroprotective agents, in this study, twenty chalcone derivatives were synthesized and evaluated for their anti-necroptosis and nephroprotective activities. Among the chalcone derivatives, Cpd-2 exhibited the most potent anti-necroptosis activity (IC₅₀ = 1.08 μM) and protective activity (EC₅₀ = 1.49 μM) through directly binding to RIPK1 and blocking RIPK1-RIPK3-MLKL signaling pathway. Furthermore, Cpd-2 effectively attenuated cisplatin or hypoxia/reoxygenation (H/R)-induced injury and necroptotic inflammation in renal cell models. Moreover, in cisplatin- or ischemia/reperfusion (I/R) induced AKI mouse model, detection of creatinine and urea nitrogen in blood showed that Cpd-2 improved kidney function. PAS staining and immunofluorescence analysis indicated that Cpd-2 also reduced pathological damage and inhibited inflammatory development in kidney tissues. In summary, although some chalcone derivatives have been reported to prevent kidney injury previously, our present study not only discovered a promising leading compound Cpd-2, but also provided a novel and successful practice for the development of necroptosis inhibitors from natural products derivatives as AKI therapeutic agents. This article is protected by copyright. All rights reserved.

Tea saponin additive to extract eleutheroside B and E from Eleutherococcus senticosus by ultrasonic mediation and its application in a semi-pilot scale

The safety of ethanol in operations and its effects on human health are gradually being questioned. Under this premise, we attempted to use the natural surfactant tea saponin, which originates from the processing residues of camellia oil, as the additive of the extraction solvent and to extract eleutheroside B and eleutheroside E in the roots and rhizomes of E. senticosus by ultrasonic mediation. After a single-factor experiment, extraction kinetics at different powers and reaction temperatures, and Box-Behnken design optimization, the optimal conditions obtained were 0.3% tea saponin solution as the extraction solvent, 20 mL/g liquid-solid ratio, 250 W ultrasonic irradiation power (43.4 mW/g ultrasonic power density) and 40 min ultrasonic irradiation time. Under optimal conditions, satisfactory yields of eleutheroside B (1.06 ± 0.04 mg/g) and eleutheroside E (2.65 ± 0.12 mg/g) were obtained with semi pilot scale ultrasonic extraction equipment. The experiments showed that compared with the traditional thermal extraction process, the extraction time is significantly reduced at lower operating temperatures.

Renoprotective activity of a new amide and a new hydroxycinnamic acid derivative from the fresh roots of Rehmannia glutinosa

A new amide, named rehmagluamide (1), and a new hydroxycinnamic acid derivative, named nepetoidin F (2), together with six known compounds, 2'-O-methyluridine (3), puroglutamic acid (4), biliverdic acid (5), peterolactam (6), nicotinic acid (7), nicotinamide (8), were isolated from the fresh roots of Rehmannia glutinosa. All the structures of compounds were identified by the interpretation of their spectroscopic data and comparison with those reported in the literatures. The protective effects of compounds 1-7 on normal rat kidney tubule epithelioid (NRK-52e) cells injury induced by LPS were investigated. The results indicated that compounds 1, 2, and 7 exhibited protective effects against LPS-induced NRK 52e cells injury.

Natural products: potential treatments for cisplatin-induced nephrotoxicity

Cisplatin is a clinically advanced and highly effective anticancer drug used in the treatment of a wide variety of malignancies, such as head and neck, lung, testis, ovary, breast cancer, etc. However, it has only a limited use in clinical practice due to its severe adverse effects, particularly nephrotoxicity; 20%–35% of patients develop acute kidney injury (AKI) after cisplatin administration. The nephrotoxic effect of cisplatin is cumulative and dose dependent and often necessitates dose reduction or withdrawal. Recurrent episodes of AKI result in impaired renal tubular function and acute renal failure, chronic kidney disease, uremia, and hypertensive nephropathy. The pathophysiology of cisplatin-induced AKI involves proximal tubular injury, apoptosis, oxidative stress, inflammation, and vascular injury in the kidneys. At present, there are no effective drugs or methods for cisplatin-induced kidney injury. Recent in vitro and in vivo studies show that numerous natural products (flavonoids, saponins, alkaloids, polysaccharide, phenylpropanoids, etc.) have specific antioxidant, anti-inflammatory, and anti-apoptotic properties that regulate the pathways associated with cisplatin-induced kidney damage. In this review we describe the molecular mechanisms of cisplatin-induced nephrotoxicity and summarize recent findings in the field of natural products that undermine these mechanisms to protect against cisplatin-induced kidney damage and provide potential strategies for AKI treatment.

Syringa microphylla Diels: A comprehensive review of its phytochemical, pharmacological, pharmacokinetic, and toxicological characteristics and an investigation into its potential health benefits

BACKGROUND

Syringa microphylla Diels is a plant in the family Syringa Linn. For hundreds of years, its flowers and leaves have been used as a folk medicine for the treatment of cough, inflammation, colds, sore throat, acute hepatitis, chronic hepatitis, early liver cirrhosis, fatty liver, and oesophageal cancer.

PURPOSE

For the first time, we have comprehensively reviewed information on Syringa microphylla Diels that is not included in the Pharmacopoeia, clarified the pharmacological mechanisms of Syringa microphylla Diels and its active ingredients from a molecular biology perspective, compiled in vivo and in vitro animal experimental data and clinical data, and summarized the toxicology and pharmacokinetics of Syringa microphylla Diels. The progress in toxicology research is expected to provide a theoretical basis for the development of new drugs from Syringa microphylla Diels, a natural source of compounds that are potentially beneficial to human health.

METHODS

The PubMed, Google Scholar, China National Knowledge Infrastructure, Web of Science, SciFinder Scholar and Thomson Reuters databases were utilized to conduct a comprehensive search of published literature as of July 2021 to find original literature related to Syringa microphylla Diels and its active ingredients.

RESULTS

To date, 72 compounds have been isolated and identified from Syringa microphylla Diels, and oleuropein, verbascoside, isoacteoside, echinacoside, forsythoside B, and eleutheroside B are the main active components. These compounds have antioxidant, antibacterial, anti-inflammatory, and neuroprotective effects, and their safety and effectiveness have been demonstrated in long-term traditional applications. Molecular pharmacology experiments have indicated that the active ingredients of Syringa microphylla Diels exert their pharmacological effects in various ways, primarily by reducing oxidative stress damage via Nrf2/ARE pathway regulation, regulating inflammatory factors and inducing apoptosis through the MAPK and NF-κB pathways.

CONCLUSION

This comprehensive review of Syringa microphylla Diels provides new insights into the correlations among molecular mechanisms, the importance of toxicology and pharmacokinetics, and potential ways to address the limitations of current research. As Syringa microphylla Diels is a natural low-toxicity botanical medicine, it is worthy of development and utilization and is an excellent choice for treating various diseases.

A Comprehensive Analysis of SE-lncRNA/mRNA Differential Expression Profiles During Chondrogenic Differentiation of Human Bone Marrow Mesenchymal Stem Cells

Objective: Articular cartilage injury is common and difficult to treat clinically because of the characteristics of the cartilage. Bone marrow-derived mesenchymal stem cell (BMSC)-mediated cartilage regeneration is a promising therapy for treating articular cartilage injury. BMSC differentiation is controlled by numerous molecules and signaling pathways in the microenvironment at both the transcriptional and post-transcriptional levels. However, the possible function of super enhancer long non-coding RNAs (SE-lncRNAs) in the chondrogenic differentiation of BMSCs is still unclear. Our intention was to explore the expression profile of SE-lncRNAs and potential target genes regulated by SE-lncRNAs during chondrogenic differentiation in BMSCs.

Materials and Methods: In this study, we conducted a human Super-Enhancer LncRNA Microarray to investigate the differential expression profile of SE-lncRNAs and mRNAs during chondrogenic differentiation of BMSCs. Subsequent bioinformatic analysis was performed to clarify the important signaling pathways, SE-lncRNAs, and mRNAs associated with SE-lncRNAs regulating the chondrogenic differentiation of BMSCs.

Results: A total of 77 SE-lncRNAs were identified, of which 47 were upregulated and 30 were downregulated during chondrogenic differentiation. A total of 308 mRNAs were identified, of which 245 were upregulated and 63 were downregulated. Some pathways, such as focal adhesion, extracellular matrix (ECM)–receptor interaction, transforming growth factor-β (TGF-β) signaling pathway, and PI3K–Akt signaling pathway, were identified as the key pathways that may be implicated in the chondrogenic differentiation of BMSCs. Moreover, five potentially core regulatory mRNAs (PMEPA1, ENC1, TES, CDK6, and ADIRF) and 37 SE-lncRNAs in chondrogenic differentiation were identified by bioinformatic analysis.

Conclusion: We assessed the differential expression levels of SE-lncRNAs and mRNAs, along with the chondrogenic differentiation of BMSCs. By analyzing the interactions and co-expression, we identified the core SE-lncRNAs and mRNAs acting as regulators of the chondrogenic differentiation potential of BMSCs. Our study also provided novel insights into the mechanism of BMSC chondrogenic and cartilage regeneration.

Eleutheroside B-loaded poly (lactic-co-glycolic acid) nanoparticles protect against renal fibrosis via Smad3-dependent mechanism

Although renal fibrosis is a common complication of chronic kidney disease (CKD), effective options for its treatment are currently limited. In this study, we evaluated the renal protective effect and possible mechanism of eleutheroside B. In order to solve the allergic reactions, side effects, and low oral bioavailability of eleutheroside B, we successfully prepared PLGA (poly [lactic-co-glycolic acid])-eleutheroside B nanoparticles (NPs) with the diameter of about 128 nm. In vitro and in vivo results showed that eleutheroside B could inhibit expression levels of α-smooth muscle actin (α-SMA) and collagen I. Molecular docking results showed that eleutheroside B bound to Smad3 and significantly decreased the expression of phospho-Smad3 (p-Smad3). Silencing Smad3 reversed the fibrotic protective effect of eleutheroside B in HK2 cells. Furthermore, small animal imaging showed that NPs can selectively accumulate in the UUO kidneys of mice, and retention time reached as long as 7 days. In conclusion, our results suggested that eleutheroside B is a potential drug to protect renal fibrosis and PLGA-eleutheroside B NPs could facilitate specific targeted therapy for renal fibrosis.

Regulated cell death in cisplatin-induced AKI: relevance of myo-inositol metabolism

Regulated cell death (RCD), distinct from accidental cell death, refers to a process of well-controlled programmed cell death with well-defined pathological mechanisms. In the past few decades, various terms for RCDs were coined, and some of them have been implicated in the pathogenesis of various types of acute kidney injury (AKI). Cisplatin is widely used as a chemotherapeutic drug for a broad spectrum of cancers, but its usage was hampered because of being highly nephrotoxic. Cisplatin-induced AKI is commonly seen clinically, and it also serves as a well-established prototypic model for laboratory investigations relevant to acute nephropathy affecting especially the tubular compartment. Literature reports over a period of three decades have indicated that there are multiple types of RCDs, including apoptosis, necroptosis, pyroptosis, ferroptosis, and mitochondrial permeability transition-mediated necrosis, and some of them are pertinent to the pathogenesis of cisplatin-induced AKI. Interestingly, myo-inositol metabolism, a vital biological process that is largely restricted to the kidney, seems to be relevant to the pathogenesis of certain forms of RCDs. A comprehensive understanding of RCDs in cisplatin-induced AKI and their relevance to myo-inositol homeostasis may yield novel therapeutic targets for the amelioration of cisplatin-related nephropathy.

Eleutheroside B, a selective late sodium current inhibitor, suppresses atrial fibrillation induced by sea anemone toxin II in rabbit hearts

Eleutheroside B (EB) is the main active constituent derived from the Chinese herb Acanthopanax senticosus (AS) that has been reported to possess cardioprotective effects. In this study we investigated the effects of EB on cardiac electrophysiology and its suppression on atrial fibrillation (AF). Whole-cell recording was conducted in isolated rabbit atrial myocytes. The intracellular calcium ([Ca²⁺]_i) concentration was measured using calcium indicator Fura-2/AM fluorescence. Monophasic action potential (MAP) and electrocardiogram (ECG) synchronous recordings were conducted in Langendorff-perfused rabbit hearts using ECG signal sampling and analysis system. We showed that EB dose-dependently inhibited late sodium current (I_NaL), transient sodium current (I_NaT), and sea anemone toxin II (ATX II)-increased I_NaL with IC₅₀ values of 167, 1582, and 181 μM, respectively. On the other hand, EB (800 μM) did not affect L-type calcium current (I_CaL), inward rectifier potassium channel current (I_K), and action potential duration (APD). Furthermore, EB (300 μM) markedly decreased ATX II-prolonged the APD at 90% repolarization (APD₉₀) and eliminated ATX II-induced early afterdepolarizations (EADs), delayed afterdepolarizations (DADs), and triggered activities (TAs). Moreover, EB (200 μM) significantly suppressed ATX II-induced Na⁺-dependent [Ca²⁺]_i overload in atrial myocytes. In the Langendorff-perfused rabbit hearts, application of EB (200 μM) or TTX (2 μM) substantially decreased ATX II-induced incidences of atrial fibrillation (AF), ventricular fibrillation (VF), and heart death. These results suggest that augmented I_NaL alone is sufficient to induce AF, and EB exerts anti-AF actions mainly via blocking I_NaL, which put forward the basis of pharmacology for new clinical application of EB.

Syringin exerts neuroprotective effects in a rat model of cerebral ischemia through the FOXO3a/NF-κB pathway

Inflammation plays an important role in the pathogenesis of cerebral ischemia. Syringin (SYR) is an active substance isolated from Acanthopanax senticosus plants, and possesses anti-inflammatory and neuroprotective properties. However, its effects on cerebral ischemic injury, as well as the underlying molecular events, are still unclear. The purpose of this study was to investigate the effect of SYR in a rat model of cerebral ischemia and address the related molecular mechanism. A middle cerebral artery occlusion/reperfusion model (MCAO) was used to simulate ischemic injury. SYR treatment clearly reduced the infarct volume, decreased cerebral water content, improved the neurological score, and attenuated neuronal death. Moreover, SYR decreased the expression of NF-κB, IL-1β, IL-6, TNF-α, and MPO, promoted FOXO3a phosphorylation and cytoplasmic retention, and inhibited the nuclear translocation of NF-κB. FOXO3a knockdown by RNA interference significantly prevented SYR-induced inhibition of NF-κB-mediated inflammation. Confocal microscopy revealed that SYR reduced NF-κB translocation to the nucleus, and FOXO3a silencing reversed this effect. Finally, immunofluorescence and CO-IP experiments showed that SYR promoted the interaction between FOXO3a and NF-κB. In conclusion, SYR exerted a protective effect against brain I/R injury by reducing the inflammation accompanying cerebral ischemia. This effect was mediated by the FOXO3a /NF-κB pathway.