Estradiol attenuates ischemia reperfusion-induced acute kidney injury through PPAR-γ stimulated eNOS activation in rats

Enhanced kidney damage induced by increasing nonylphenol doses: impact on autophagy-related proteins and proinflammatory cytokines in rats

Nonylphenol (NP) is an organic pollutant and endocrine disruptor chemical that has harmful effects on the environment and living organisms. This study looked at whether kidney tissues subjected to increasing doses of nonylphenol generated alterations in histopathologic, pro-inflammatory, and autophagic markers. Fifty rats were divided into five groups of ten each: group I: healthy group, II: control (corn oil), group III: 25 μl/kg NP, group IV: 50 μl/kg NP, group V: 75 μl/kg NP. The kidney tissue samples were obtained for histopathological, immunohistochemical, and biochemical analyses. The histological deteriorations observed in all NP groups included tubular epithelial cell degeneration, inflammation areas, and hemorrhage. The immunohistochemical investigations showed that NP significantly elevated the autophagy markers (Beclin-1, LC3A/B, p62), pro-inflammatory cytokines (TNF-α, IL-6), HIF-1α, and eNOS in group III, IV and V compared with group I and II. The biochemical analysis also revealed that pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6) increased in correlation with the NP doses, but only IL-1β reached statistical significance in NP treated rats kidney tissue. The biochemical findings have been confirmed by the histological studies. The damage to renal tissue caused by NP exposure may worsen it by increasing inflammatory and autophagic markers.

Interrogating the estrogen-mediated regulation of adrenocortical Klotho expression using ovariectomized albino rat model exposed to repeated restraint stress

Reproductive aging is associated with altered stress response and many other menopausal symptoms. Little is known about the adrenal expression of the anti-aging protein Klotho or how it is modulated by estrogen in ovariectomized stressed rats. Fifty-six Wistar female rats were assigned into seven equal groups. Sham-operated (Sham), sham stressed (Sham/STS), ovariectomized (OVR), ovariectomized stressed (OVR/STS), ovariectomized stressed rosiglitazone-treated (OVR/STS/R), ovariectomized stressed estrogen-treated (OVR/STS/E), and ovariectomized stressed estrogen/GW9662 co-treated (OVR/STS/E/GW) groups. All stressed rats were subjected daily to a one-hour restraint stress test for 19 days. At the end of the experiment, blood was collected for serum corticosterone (CORT) analysis. Adrenal tissues were obtained and prepared for polymerase chain reaction (PCR) assay, hematoxylin and eosin (H&E), immunohistochemistry-based identification of Klotho and PPAR-γ, and Oil Red O (ORO) staining. The rise in serum CORT was negligible in the OVR/STS group, in contrast to the Sham/STS group. The limited CORT response in the former group was restored by estrogen and rosiglitazone and blocked by estrogen/GW9226 co-administration. ORO-staining revealed a more evident reduction in the adrenal fat in the OVR/STS group, which was reversed by estrogen and counteracted by GW. Also, there was a comparable expression pattern of Klotho and PPAR-γ in the adrenals. The adrenal Klotho decreased in the OVR/STS group, but was reversed by estrogen treatment. GW9226/estrogen co-treatment interfered with the regulatory effect of estrogen on Klotho. The study suggested modulation of the adrenal Kotho expression by estrogen, in the ovariectomized rats subjected to a restraint stress test. This estrogen-provided adrenal protection might be mediated by PPAR-γ activation.

The metabolic pathway regulation in kidney injury and repair

Kidney injury and repair are accompanied by significant disruptions in metabolic pathways, leading to renal cell dysfunction and further contributing to the progression of renal pathology. This review outlines the complex involvement of various energy production pathways in glucose, lipid, amino acid, and ketone body metabolism within the kidney. We provide a comprehensive summary of the aberrant regulation of these metabolic pathways in kidney injury and repair. After acute kidney injury (AKI), there is notable mitochondrial damage and oxygen/nutrient deprivation, leading to reduced activity in glycolysis and mitochondrial bioenergetics. Additionally, disruptions occur in the pentose phosphate pathway (PPP), amino acid metabolism, and the supply of ketone bodies. The subsequent kidney repair phase is characterized by a metabolic shift toward glycolysis, along with decreased fatty acid β-oxidation and continued disturbances in amino acid metabolism. Furthermore, the impact of metabolism dysfunction on renal cell injury, regeneration, and the development of renal fibrosis is analyzed. Finally, we discuss the potential therapeutic strategies by targeting renal metabolic regulation to ameliorate kidney injury and fibrosis and promote kidney repair.

The combinatorial effect of age and biological sex on alloimmunity and transplantation outcome

Both age and biological sex affect transplantation outcomes. We have recently shown in a large volume clinical analysis utilizing the SRTR data that graft survival is inferior in young female kidney transplant recipients. In this multi-factorial analysis, older female recipients presented with a trend towards improved transplant outcomes compared to both young female recipients and male recipients of any age. Those data supported by reports of those of others suggest that sex and age impact alloimmune responses both, individually and synergistically. Biological sex and hormone levels change throughout a lifetime with recognized effects on longevity in addition to an impact on the development and course of several disease preconditions. Detailed mechanisms of those sex and age-specific aspects have thus far been studied outside of transplantation. Effects on alloimmunity are largely unknown. Moreover, the combinatorial impact that both, biological sex and age have on transplant outcomes is not understood. Here, we summarize available data that analyze how age in combination with biological sex may shape alloimmune responses and affect transplant outcomes.

Activation of GPER1 in macrophages ameliorates UUO-induced renal fibrosis

Numerous studies have proven the critical role of macrophages in the renal fibrosis process. Notably, G Protein-coupled Estrogen Receptor 1 (GPER1), a novel estrogen receptor, has been shown to play a ubiquitous role in regulating macrophage activities and proinflammatory pathways. However, the precise role of GPER1 in macrophage-mediated renal fibrosis is unknown. In this study, we aimed to investigate the function of macrophage GPER1 in the UUO-induced renal fibrosis model. Compared to vehicle-treated ovariectomized (OVX) female and male unilateral ureteral obstruction (UUO) models, we observed that G-1 (GPER1 agonist)-treated OVX female and male UUO mice had fewer renal fibrotic lesions and less M1 and M2 macrophage infiltration in the kidney tissues. Conversely, Gper1 deletion in male UUO mice accelerated renal fibrosis and increased inflammation. In vitro studies also revealed that GPER1 activation reduced M0 macrophage polarization towards M1 or M2 phenotypes. The RNA-sequencing analysis and immunoblotting indicated that GPER1 activation was primarily involved in downregulating immune pathways activation and inactivating MAPK pathways. Tubular epithelial cells co-cultured with G-1-pretreated M1 macrophages exhibited fewer injuries and immune activation. In addition, fibroblasts co-cultured with G-1-pretreated M2 macrophages showed downregulated extracellular matrix expression. Overall, this is the first study to demonstrate the effect of GPER1 on macrophage-mediated renal fibrosis via inhibition of M1 and M2 macrophage activation. These findings indicate that GPER1 may be a promising therapeutic target for treating renal fibrosis.

Maternal dexamethasone exposure does not affect glucose tolerance but alters renal haemodynamics in F1 rats in a sex-dependent manner

INTRODUCTION

Prenatal programming with dexamethasone increases the risk of the development of hyperglycaemia and insulin resistance, leading to diabetes in adulthood. Dexamethasone also causes a decline in renal glomerular filtration in the adult offspring. Sodium-glucose cotransporter-2 (SGLT2) plays a significant role in regulating blood glucose and renal haemodynamics in diabetic patients. However, the role of SGLT2 in dexamethasone-induced programming and the putative sex-dependent effects on the changes named earlier is unknown. Therefore, this study aimed to investigate the impact of maternal dexamethasone treatment on glucose tolerance, insulin sensitivity, renal perfusion and renal function in adult male and female offspring and the possible contribution of SGLT2 to these changes.

METHODS AND RESULTS

Pregnant Sprague Dawley rats (F0 ) were treated with either vehicle or dexamethasone (0.2 mg/kg ip) from gestation Day 15 to 20. F1 males and F1 females were randomly selected from each mother at 4 months of age. There was no change in serum Na+ , Na+ excretion rate, glucose tolerance or insulin sensitivity in F1 male or female rats. However, dexamethasone caused significant glomerular hypertrophy and decreases in CSinistrin and CPAH indicating decreased glomerular filtration rate and renal plasma flow, respectively, in dexamethasone-treated F1 male but not female rats. Dexamethasone did not affect SGLT2 mRNA or protein expression in F1 males or females.

CONCLUSION

We conclude that dexamethasone-mediated prenatal programming of glomerular volume, renal function and haemodynamics is sex-dependent, occurring only in adult male offspring.

Sex differences in obesity-induced renal lipid accumulation revealed by lipidomics: a role of adiponectin/AMPK axis

BACKGROUND

Sex differences have been observed in the development of obesity-related complications in patients, as well as in animal models. Accumulating evidence suggests that sex-dependent regulation of lipid metabolism contributes to sex-specific physiopathology. Lipid accumulation in the renal tissue has been shown to play a major role in the pathogenesis of obesity-induced kidney injury. Unlike in males, the physiopathology of the disease has been poorly described in females, particularly regarding the lipid metabolism adaptation.

METHODS

Here, we compared the lipid profile changes in the kidneys of female and male mice fed a high-fat diet (HFD) or low-fat diet (LFD) by lipidomics and correlated them with pathophysiological changes.

RESULTS

We showed that HFD-fed female mice were protected from insulin resistance and hepatic steatosis compared to males, despite similar body weight gains. Females were particularly protected from renal dysfunction, oxidative stress, and tubular lipid accumulation. Both HFD-fed male and female mice presented dyslipidemia, but lipidomic analysis highlighted differential renal lipid profiles. While both sexes presented similar neutral lipid accumulation with obesity, only males showed increased levels of ceramides and phospholipids. Remarkably, protection against renal lipotoxicity in females was associated with enhanced renal adiponectin and AMP-activated protein kinase (AMPK) signaling. Circulating adiponectin and its renal receptor levels were significantly lower in obese males, but were maintained in females. This observation correlated with the maintained basal AMPK activity in obese female mice compared to males.

CONCLUSIONS

Collectively, our findings suggest that female mice are protected from obesity-induced renal dysfunction and lipotoxicity associated with enhanced adiponectin and AMPK signaling compared to males.

Evaluation of aristolochic acid Ι nephrotoxicity in mice via 1H NMR quantitative metabolomics and network pharmacology approaches

Background

Although many studies have shown that herbs containing aristolochic acids can treat various human diseases, AAΙ in particular has been implicated as a nephrotoxic agent.

Methods and results

Here, we detail the nephrotoxic effect of AAΙ via an approach that integrated 1H NMR-based metabonomics and network pharmacology. Our findings revealed renal injury in mice after the administration of AAΙ. Metabolomic data confirmed significant differences among the renal metabolic profiles of control and model groups, with significant reductions in 12 differential metabolites relevant to 23 metabolic pathways. Among them, there were seven important metabolic pathways: arginine and proline metabolism; glycine, serine, and threonine metabolism; taurine and hypotaurine metabolism; ascorbate and aldehyde glycolate metabolism; pentose and glucosinolate interconversion; alanine, aspartate, and glutamate metabolism; and glyoxylate and dicarboxylic acid metabolism. Relevant genes, namely, nitric oxide synthase 1 (NOS1), pyrroline-5-carboxylate reductase 1 (PYCR1), nitric oxide synthase 3 (NOS3) and glutamic oxaloacetic transaminase 2 (GOT2), were highlighted via network pharmacology and molecular docking techniques. Quantitative real-time PCR findings revealed that AAI administration significantly downregulated GOT2 and NOS3 and significantly upregulated NOS1 and PYCR1 expression and thus influenced the metabolism of arginine and proline.

Conclusion

This work provides a meaningful insight for the mechanism of AAΙ renal injury.

Effect of the Non-steroidal Anti-inflammatory Drug Diclofenac on Ischemia-Reperfusion Injury in Rat Liver: A Nitric Oxide-Dependent Mechanism

Ischemia/reperfusion injury (IRI) is an inevitable complication of liver surgery and transplantation. The purpose of this study was to examine the beneficial effects of diclofenac on hepatic IRI and the mechanism behind it. Wistar rats' livers were subjected to warm ischemia for 60 min followed by 24 h of reperfusion. Diclofenac was administered intravenously 15 min before ischemia at 10, 20, and 40 mg/kg body weight. To determine the mechanism of diclofenac protection, the NOS inhibitor L-Nitro-arginine methyl ester (L-NAME) was administered intravenously 10 min after diclofenac injection (40 mg/kg). Liver injury was evaluated by aminotransferases (ALT and AST) activities and histopathological analysis. Oxidative stress parameters (SOD, GPX, MPO, GSH, MDA, and PSH) were also determined. Then, eNOS gene transcription and p-eNOS and iNOS protein expressions were evaluated. The transcription factors PPAR-γ and NF-κB in addition to the regulatory protein IκBα were also investigated. Finally, the gene expression levels of inflammatory (COX-2, IL-6, IL-1β, IL-18, TNF-α, HMGB-1, and TLR-4) and apoptosis (Bcl-2 and Bax) markers were measured. Diclofenac, at the optimal dose of 40 mg/kg, decreased liver injury and maintained histological integrity. It also reduced oxidative stress, inflammation, and apoptosis. Its mechanism of action essentially depended on eNOS activation rather than COX-2 inhibition, since pre-treatment with L-NAME abolished all the protective effects of diclofenac. To our knowledge, this is the first study demonstrating that diclofenac protects rat liver against warm IRI through the induction of NO-dependent pathway. Diclofenac reduced oxidative balance, attenuated the activation of the subsequent pro-inflammatory response and decreased cellular and tissue damage. Therefore, diclofenac could be a promising molecule for the prevention of liver IRI.

Estrogen Signaling Influences Nephron Segmentation of the Zebrafish Embryonic Kidney

Despite significant advances in understanding nephron segment patterning, many questions remain about the underlying genes and signaling pathways that orchestrate renal progenitor cell fate choices and regulate differentiation. In an effort to identify elusive regulators of nephron segmentation, our lab conducted a high-throughput drug screen using a bioactive chemical library and developing zebrafish, which are a conserved vertebrate model and particularly conducive to large-scale screening approaches. 17β-estradiol (E2), which is the dominant form of estrogen in vertebrates, was a particularly interesting hit from this screen. E2 has been extensively studied in the context of gonad development, but roles for E2 in nephron development were unknown. Here, we report that exogenous estrogen treatments affect distal tubule composition, namely, causing an increase in the distal early segment and a decrease in the neighboring distal late. These changes were noted early in development but were not due to changes in cell dynamics. Interestingly, exposure to the xenoestrogens ethinylestradiol and genistein yielded the same changes in distal segments. Further, upon treatment with an estrogen receptor 2 (Esr2) antagonist, PHTPP, we observed the opposite phenotypes. Similarly, genetic deficiency of the Esr2 analog, esr2b, revealed phenotypes consistent with that of PHTPP treatment. Inhibition of E2 signaling also resulted in decreased expression of essential distal transcription factors, irx3b and its target irx1a. These data suggest that estrogenic compounds are essential for distal segment fate during nephrogenesis in the zebrafish pronephros and expand our fundamental understanding of hormone function during kidney organogenesis.

Nephropathy 1st inhibits renal fibrosis by activating the PPARγ signaling pathway

Renal fibrosis is a manifestation of kidney injury. Nephropathy 1st is a traditional Chinese herbal medicine that has been used as a therapy for kidney disease, but the underlying mechanisms remain elusive. The aim of this study was to investigate the role and underlying mechanisms of Nephropathy 1st on the progression of kidney disease. In the present study, unilateral ureteral obstruction was performed to establish the renal fibrosis rat model. By hematoxylin–eosin staining and immunohistochemical staining analysis, the severity of renal fibrosis was evaluated in vivo. Serum creatinine (CREA) and urea nitrogen (BUN) were measured by ELISA. The expression levels of Col-I, FN, PPARγ, and Klotho were measured by Western blot in rat NRK-49F cells and in fibrotic rats. GW9662 was used to inhibit PPARγ signaling. Metabonomic analysis showed metabolic differences among groups. Nephropathy 1st administration alleviated the progression of rat renal fibrosis and reduced serum creatinine (Scr) and BUN levels. Mechanistically, Nephropathy 1st promoted the expression of PPARγ and thus activated PPARγ signaling, thereby reducing the pro-fibrotic phenotypes of fibroblasts. The therapeutic effect of Nephropathy 1st was abrogated by the PPARγ inhibitor GW9662. Moreover, Nephropathy 1st normalized the dysregulated lipid metabolism in renal fibrosis rats. In conclusion, Nephropathy 1st alleviates renal fibrosis development in a PPARγ-dependent manner.

Calycosin attenuates renal ischemia/reperfusion injury by suppressing NF-κB mediated inflammation via PPARγ/EGR1 pathway

Renal ischemia reperfusion injury (IRI) is a leading and common cause of acute kidney injury (AKI), and inflammation is a critical factor in ischemic AKI progression. Calycosin (CAL), a major active component of Radix astragali, has been reported to have anti-inflammatory effect in multiple organs. However, whether CAL can alleviate renal IRI and its mechanism remain uncertain. In the present study, a renal IRI model is established by bilateral renal pedicles occlusion for 35 min in male C57BL/6 mice, and the effect of CAL on renal IRI is measured by serum creatinine and pathohistological assay. Hypoxia/reoxygenation (H/R) stimulated human renal tubular epithelial cells HK-2 were applied to explore the regulatory mechanisms of CAL. Luciferase reporter assay and molecular docking were applied to identify the CAL's target protein and pathway. In the mice with renal IRI, CAL dose dependently alleviated the renal injury and decreased nuclear factor kappa B (NF-κB) mediated inflammatory response. Bioinformatics analysis and experiments showed that early growth response 1 (EGR1) increased in mice with renal IRI and promoted NF-κB mediated inflammatory processes, and CAL dose-dependably reduced EGR1. Through JASPAR database and luciferase reporter assay, peroxisome proliferator-activated receptor γ (PPARγ) was predicted to be a transcription factor of EGR1 and repressed the expression of EGR1 in renal tubular epithelial cells. CAL could increase PPARγ in a dose dependent manner in mice with renal IRI and molecular docking predicted CAL could bind stably to PPARγ. In HK-2 cells after H/R, CAL increased PPARγ, decreased EGR1, and inhibited NF-κB mediated inflammatory response. However, PPARγ knockdown by siRNA transfection abrogated the anti-inflammation therapeutic effect of CAL. CAL produced a protective effect on renal IRI by attenuating NF-κB mediated inflammatory response via PPARγ/EGR1 pathway.

Estrogen Protects against Renal Ischemia-Reperfusion Injury by Regulating Th17/Treg Cell Immune Balance

Inflammation is a critical mediator of renal ischemia-reperfusion (I/R) injury (IRI), and T lymphocytes exert a key role in the renal IRI-induced inflammation. Connexin 43 (Cx43) is related to the maintenance of T lymphocyte homeostasis. Various preclinical researches have reported that estrogen is a renoprotective agent based on its anti-inflammatory potential. The present research is aimed at studying the role of T lymphocytes activated by Cx43 in 17β-estradiol-mediated protection against renal IRI. Female rats were classified into six groups: control rats, I/R rats, ovariectomized rats, ovariectomized I/R rats, and ovariectomized rats treated with 17β-estradiol or gap27. Levels of serum creatinine (Scr) and blood urea nitrogen (BUN) and Paller scoring were dramatically increased in I/R rats, especially in ovariectomized rats. By contrast, these indicators were markedly decreased by administering estradiol or gap27. Immunofluorescence staining revealed that CD4⁺ T cells infiltrated kidney tissues in the early stage of IRI. In both peripheral blood and renal tissue, the proportion of CD3⁺CD4⁺ T cells and ratio of CD4⁺ to CD8⁺ were high in I/R rats, especially in ovariectomized rats. The proportion of CD3⁺CD8⁺ T cells was low in peripheral blood but high in renal tissues. Administration of estrogen or Gap27 reversed these effects. IL-17 levels in both serum and tissue homogenate were significantly increased in ovariectomized rats subjected to I/R but significantly decreased in estrogen or gap 27 treated rats. The opposite trend was observed for IL-10 levels. Correlation analysis demonstrated that IL-17 was correlated positively with BUN, Scr, and Paller scores, while IL-10 was negatively correlated with these indicators. Western blot showed that Cx43 expression was markedly increased in the peripheral blood T lymphocytes of I/R rats, especially ovariectomized rats. After intervention with estrogen and gap27, Cx43 expression was significantly downregulated. These findings indicate that Cx43 may participate in the regulation of Th17/Treg balance by estrogen against renal IRI.

An integrated study of Shenling Baizhu San against hyperuricemia: Efficacy evaluation, core target identification and active component discovery

ETHNOPHARMACOLOGICAL RELEVANCE

Shenling Baizhu San (SLBZ) is a famous Traditional Chinese Medicine (TCM) formula that strengthens the spleen for replenishing qi, removing dampness, and inducing diuresis to relieve diarrhea. Combining the TCM interpretation that dampness is a vital pathogenesis factor in hyperuricemia occurrence and development, SLBZ has excellent potential against hyperuricemia from the perspective of TCM theories.

AIM OF THE STUDY

This study aimed to investigate the efficacy of SLBZ against hyperuricemia and its possible mechanism with emphasis on the active components and the core targets.

MATERIALS AND METHODS

In the present study, we employed meta-analysis and a hyperuricemia quail model to evaluate the uric acid-lowering effect of SLBZ. Bodyweight, serum uric acid, and excreta uric acid levels in quails were assessed. Subsequently, we analyzed the potential active components and core targets of SLBZ against hyperuricemia by network pharmacology and calculated their interaction using molecular docking. Furthermore, the hyperuricemia rats treated with interfering agents of core targets were established to determine the central role of selected targets in hyperuricemia progression. Besides, we isolated and characterized the primary renal tubular epithelial cells of quails to verify the active components and core targets of SLBZ against hyperuricemia. Western blotting was used to observe the expression of core targets treated with active components under the stimulation of interfering agents.

RESULTS

Data from meta-analysis and animal experiments showed that SLBZ could work effectively against hyperuricemia. Hyperuricemia quails treated with SLBZ displayed significantly reduced serum uric acid levels accompanied by increased excretion of uric acid. According to network pharmacology and molecular docking results, 34 potential active components and the core target peroxisome proliferator-activated receptor gamma (PPARγ) for SLBZ against hyperuricemia were identified. The decreased serum uric acid levels in hyperuricemia rats treated with rosiglitazone, an agonist of PPARγ, confirms the essential role of PPARγ in the pathological process of hyperuricemia. Moreover, we first successfully isolated and characterized the primary renal tubular epithelial cells of quails and observed enhanced phosphorylation of PPARγ at Ser273 in cells handled with high-level uric acid. Whereas, the enhanced expression of p-PPARγ Ser273 could be down-regulated by luteolin and naringenin, two active components of SLBZ against hyperuricemia.

CONCLUSION

In summary, SLBZ is a promising anti-hyperuricemia agent, and luteolin and naringenin are the active components for SLBZ against hyperuricemia by down-regulating phosphorylation of PPARγ at Ser273.

Effects of propofol on macrophage activation and function in diseases

Macrophages work with monocytes and dendritic cells to form a monocyte immune system, which constitutes a powerful cornerstone of the immune system with their powerful antigen presentation and phagocytosis. Macrophages play an essential role in infection, inflammation, tumors and other pathological conditions, but these cells also have non-immune functions, such as regulating lipid metabolism and maintaining homeostasis. Propofol is a commonly used intravenous anesthetic in the clinic. Propofol has sedative, hypnotic, anti-inflammatory and anti-oxidation effects, and it participates in the body’s immunity. The regulation of propofol on immune cells, especially macrophages, has a profound effect on the occurrence and development of human diseases. We summarized the effects of propofol on macrophage migration, recruitment, differentiation, polarization, and pyroptosis, and the regulation of these propofol-regulated macrophage functions in inflammation, infection, tumor, and organ reperfusion injury. The influence of propofol on pathology and prognosis via macrophage regulation is also discussed. A better understanding of the effects of propofol on macrophage activation and function in human diseases will provide a new strategy for the application of clinical narcotic drugs and the treatment of diseases.

Does G Protein-Coupled Estrogen Receptor 1 Contribute to Cisplatin-Induced Acute Kidney Injury in Male Mice?

Nephrotoxicity is the dose-limiting side-effect of the chemotherapeutic agent cisplatin (Cp). Recent evidence points to renal protective actions of G protein-coupled estrogen receptor 1 (GPER1). In addition, it has been shown that GPER1 signaling elicits protective actions against acute ischemic injuries that involve multiple organ systems; however, the involvement of GPER1 signaling in Cp-induced acute kidney injury (AKI) remains unclear. This study tested whether genetic deletion of GPER1 exacerbates Cp-induced AKI in male mice. We subjected male mice, homozygous (homo) and heterozygous (het) knockout for the GPER1 gene, and wild-type (WT) littermates to Cp or saline injections and assessed markers for renal injury on the third day after injections. We also determined serum levels of proinflammatory markers in saline and Cp-treated mice. Given the protective role of heme oxygenase-1 (HO-1) in Cp-mediated apoptosis, we also investigated genotypic differences in renal HO-1 abundance, cell death, and proliferation by Western blotting, the TUNEL assay, and Ki67 immunostaining, respectively. Cp increased serum creatinine, urea, and neutrophil gelatinase-associated lipocalin (NGAL) levels, the renal abundance of kidney injury molecule-1, and NGAL in all groups. Cp-induced AKI resulted in comparable histological evidence of injury in all genotypes. WT and homo mice showed greater renal HO-1 abundance in response to Cp. Renal HO-1 abundance was lower in Cp-treated homo, compared to Cp-treated WT mice. Of note, GPER1 deletion elicited a remarkable increase in renal apoptosis; however, no genotypic differences in cell proliferation were observed. Cp augmented kidney Ki67-positive counts, regardless of the genotype. Overall, our data do not support a role for GPER1 in mediating Cp-induced renal injury. GPER1 deletion promotes renal apoptosis and diminishes HO-1 induction in response to Cp, suggesting that GPER1 may play cytoprotective and anti-apoptotic actions in AKI. GPER1-induced regulation of HO-1 and apoptosis may offer novel therapeutic targets for the treatment of AKI.

Baseline Serum Estradiol Level Is Associated with Acute Kidney Injury in Patients with Moderately Severe and Severe Acute Pancreatitis

Background. Sexual dimorphism with critical diseases has been documented. However, the role of serum sex hormones for the presence of acute kidney injury (AKI) in moderately or severe acute pancreatitis (MSAP and SAP) patients remains controversial. Here we set out to evaluate whether early (first 48 h) serum estradiol level is associated with AKI in patients with MSAP and SAP. Patients and Methods. We retrospectively collected data from patients with preliminary diagnosis of MSAP and SAP from the Affiliated Hospital of Yangzhou University between January 2014 and June 2018. Serum sex hormones were extracted for further assessment within first 48 h following admission. Logistic regression analysis and the receiving operating characteristic (ROC) curve were applied to evaluate the association and correlation between serum sex hormones and AKI. Results. Data from a total of 122 patients with MSAP or SAP were enrolled in this study. There were no differences in the incidence of AKI between males and females. However, comparing with patients without AKI, those with AKI saw higher estradiol level ( $p\le 0.01$ ) and slight higher progesterone level ( $p=0.014$ ) but similar testosterone level ( $p=0.668$ ). Interestingly, during both the manual selection and the stepwise backward logistic regression analysis, serum estradiol level was independently associated with AKI in patients with MSAP and SAP (OR 4.699, CI 1.783-12.386, and $p=0.002$ ). Additionally, area under the curve of ROC (AUCROC) showed that serum estradiol level was a proper predictor for AKI (area under the curve 0.875). Specifically, the serum estradiol level of 223.15 pg/mL demonstrated a 92.3% sensitive and a 79.3% specificity in predicting AKI of MSAP and SAP patients, respectively. Conclusions. High baseline serum estradiol level appears to be an independent risk factor for AKI in patients with MSAP and SAP. It also tends to be an appropriate indicator for AKI.

The Selective Estrogen Receptor Modulator, Raloxifene, Is Protective Against Renal Ischemia-Reperfusion Injury

BACKGROUND

There is increasing evidence that estrogen is responsible for improved outcomes in female kidney transplant recipients. Although the exact mechanism is not yet known, estrogen appears to exert its protective effects by ameliorating ischemia-reperfusion injury (IRI). In this study, we have examined whether the beneficial effects of exogenous estrogen in renal IRI are replicated by therapy with any one of several selective estrogen receptor modulators.

METHODS

C57BL/6 adult mice underwent standardized warm renal ischemia for 28 min after being injected with the selective estrogen receptor modulators, raloxifene, lasofoxifene, tamoxifen, bazedoxifene, or control vehicle (dimethyl sulfoxide), at 16 and 1 h before IRI. Plasma concentrations of blood urea nitrogen and creatinine were assessed 24, 48, 72, and 96 h post-IRI. Tissue was collected 30 d postischemia for fibrosis analysis using Sirius Red staining.

RESULTS

Raloxifene treatment in female mice resulted in significantly lower blood urea nitrogen and creatinine after IRI and significantly lower fibrosis 30 d following IRI.

CONCLUSIONS

Raloxifene is protective against both acute kidney injury and fibrosis resulting from renal IRI in a mouse model.

Estradiol Ameliorates Acute Kidney Ischemia-Reperfusion Injury by Inhibiting the TGF-βRI-SMAD Pathway

Renal ischemia–reperfusion injury (IRI) is less extensive in females than males in both animals and humans; however, this protection diminishes after menopause, suggesting that estrogen plays a pivotal role in IRI, but the underlying mechanism remains largely unknown. Our study found that 45 min of warm ischemia was sufficient to induce significant pathological changes without causing death in model animals. Compared with male rats, female rats exhibited less extensive apoptosis, kidney injury, and fibrosis; these effects were worsened in ovariectomized (OVX) rats and ameliorated upon estradiol (E₂) supplementation. Furthermore, the levels of TGF-βRI, but not TGF-βRII or TGF-β1, were significantly increased in OVX rats, accompanied by phosphorylated SMAD2/3 activation. Interestingly, the alteration trend of the nuclear ERα level was opposite that of TGF-βRI. Furthermore, dual luciferase reporter and chromatin immunoprecipitation assays showed that ERα could bind to the promoter region of TGF-βRI and negatively regulate its mRNA expression. Moreover, an in vitro study using NRK-52E cells showed that ERα knockdown blocked E₂-mediated protection, while TGF-βRI knockdown protected cells against hypoxic insult. The findings of this study suggest that renal IRI is closely related to the TGF-βRI-SMAD pathway in females and that E₂ exert its protective effect via the ERα-mediated transcriptional inhibition of TGF-βRI expression.

Single cell sequencing coupled with bioinformatics reveals PHYH as a potential biomarker in kidney ischemia reperfusion injury

Ischemia reperfusion injury(IRI) is an important factor affecting the early function and long-term survival of transplanted kidney. Single cell RNA sequencing (scRNA-seq) is a powerful method for investigating cell-specific transcriptome changes in the kidney. This study aimed to identify the significant cell type and potential biomarkers in IRI. First, we downloaded the IRI related scRNA dataset GSE139506 from the GEO database. Then, classification of cell type was characterized and proximal tubule cell (PTC) was identified as a significant cell type. The functional enrichment analysis indicated that PTC were related to kidney function and is significant in the ferroptosis of IRI. Analyses of three-dimensional structure and iron binding substructure of protein was carried out basing on SWISS-MODEL database. Finally, we constructed the murine model with IRI and verify the higher expression of PHYH in IRI by PCR, Western blot (WB) and Immunohistochemistry (IHC) experiments. In conclusion, this study provided novel insights on the cell-type-specific expression gene biomarker in IRI pathogenesis.

Ebselen ameliorates renal ischemia-reperfusion injury via enhancing autophagy in rats

Renal ischemia-reperfusion (I/R) injury is one of the most common causes of chronic kidney disease (CKD). It brings unfavorable outcomes to the patients and leads to a considerable socioeconomic burden. The study of renal I/R injury is still one of the hot topics in the medical field. Ebselen is an organic selenide that attenuates I/R injury in various organs. However, its effect and related mechanism underlying renal I/R injury remains unclear. In this study, we established a rat model of renal I/R injury to study the preventive effect of ebselen on renal I/R injury and further explore the potential mechanism of its action. We found that ebselen pretreatment reduced renal dysfunction and tissue damage caused by renal I/R. In addition, ebselen enhanced autophagy and inhibited oxidative stress. Additionally, ebselen pretreatment activated the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway. The protective effect of ebselen was suppressed by autophagy inhibitor wortmannin. In conclusion, ebselen could ameliorate renal I/R injury, probably by enhancing autophagy, activating the Nrf2 signaling pathway, and reducing oxidative stress.

Emerging Roles for G Protein-Coupled Estrogen Receptor 1 in Cardio-Renal Health: Implications for Aging

Cardiovascular (CV) and renal diseases are increasingly prevalent in the United States and globally. CV-related mortality is the leading cause of death in the United States, while renal-related mortality is the 8th. Despite advanced therapeutics, both diseases persist, warranting continued exploration of disease mechanisms to develop novel therapeutics and advance clinical outcomes for cardio-renal health. CV and renal diseases increase with age, and there are sex differences evident in both the prevalence and progression of CV and renal disease. These age and sex differences seen in cardio-renal health implicate sex hormones as potentially important regulators to be studied. One such regulator is G protein-coupled estrogen receptor 1 (GPER1). GPER1 has been implicated in estrogen signaling and is expressed in a variety of tissues including the heart, vasculature, and kidney. GPER1 has been shown to be protective against CV and renal diseases in different experimental animal models. GPER1 actions involve multiple signaling pathways: interaction with aldosterone and endothelin-1 signaling, stimulation of the release of nitric oxide, and reduction in oxidative stress, inflammation, and immune infiltration. This review will discuss the current literature regarding GPER1 and cardio-renal health, particularly in the context of aging. Improving our understanding of GPER1-evoked mechanisms may reveal novel therapeutics aimed at improving cardio-renal health and clinical outcomes in the elderly.

Protective effect of estradiol copreservation against kidney ischemia-reperfusion injury

Ischemia-reperfusion injury (IRI) is the major cause of delayed graft function (DGF) during the posttransplantation period. Estradiol (E2) prevents IRI-induced kidney dysfunction and tissue injury. However, many side effects limit E2's in vivo application. Recent evidence uncovers E2's expanded use in the field of transplantation. We aimed to study if and how E2 exerts protective activity during the period of kidney organ preservation. The autologous kidney transplant model in rats was first established. Rats were divided into 5 groups: normal group (N), sham group (sham), static cold storage (SCS) 4 hours group (control), SCS 4 hours + ethanol (1 µL/mL) group (solvent), and SCS 4 hours + ethanol (1 µL/mL) + E2 (1000 ng/mL) group (E2). ERα expression under hypothermia was measured by western blotting. Moreover, biochemical analyses of plasma levels of creatinine, BUN, estradiol, and testosterone were examined. Among all groups, kidney tissues were collected and processed for further western blot analysis about ERα, eNOS, Bcl-2, and Bax expression, histological analyses such as H&E staining to evaluate pathological severity. In addition, a TUNEL assay is performed to evaluate apoptosis. E2 copreservation upregulated ERα expression under hypothermia. Moreover, E2 copreservation reduced levels of creatinine and BUN in plasma but without affecting estradiol and testosterone. Further, E2 copreservation increased expression of eNOS and antiapoptotic Bcl-2 and decreases expression of proapoptotic Bax. E2 copreservation significantly inhibited IRI-induced apoptosis and evidently improved pathological severity in the kidney of rats. E2 copreservation exerts protective activity against IRI-induced pro-inflammatory and proapoptotic effects in kidneys during organ preservation time and improves transplanted kidney function.

Female and male mice have differential longterm cardiorenal outcomes following a matched degree of ischemia-reperfusion acute kidney injury

Acute kidney injury (AKI) is common in patients, causes systemic sequelae, and predisposes patients to long-term cardiovascular disease. To date, studies of the effects of AKI on cardiovascular outcomes have only been performed in male mice. We recently demonstrated that male mice developed diastolic dysfunction, hypertension and reduced cardiac ATP levels versus sham 1 year after AKI. The effects of female sex on long-term cardiac outcomes after AKI are unknown. Therefore, we examined the 1-year cardiorenal outcomes following a single episode of bilateral renal ischemia-reperfusion injury in female C57BL/6 mice using a model with similar severity of AKI and performed concomitantly to recently published male cohorts. To match the severity of AKI between male and female mice, females received 34 min of ischemia time compared to 25 min in males. Serial renal function, echocardiograms and blood pressure assessments were performed throughout the 1-year study. Renal histology, and cardiac and plasma metabolomics and mitochondrial function in the heart and kidney were evaluated at 1 year. Measured glomerular filtration rates (GFR) were similar between male and female mice throughout the 1-year study period. One year after AKI, female mice had preserved diastolic function, normal blood pressure, and preserved levels of cardiac ATP. Compared to males, females demonstrated pathway enrichment in arginine metabolism and amino acid related energy production in both the heart and plasma, and glutathione in the plasma. Cardiac mitochondrial respiration in Complex I of the electron transport chain demonstrated improved mitochondrial function in females compared to males, regardless of AKI or sham. This is the first study to examine the long-term cardiac effects of AKI on female mice and indicate that there are important sex-related cardiorenal differences. The role of female sex in cardiovascular outcomes after AKI merits further investigation.

A cohort study investigating the occurrence of differences in care provided to men and women in an intensive care unit

It has been reported that there are differences in the care given within the intensive care unit (ICU) between men and women. The aim of this study is to investigate if any differences still exist between men and women regarding the level of intensive care provided, using prespecified intensive care items. This is a retrospective cohort study of 9017 ICU patients admitted to a university hospital between 2006 and 2016. Differences in use of mechanical ventilation, invasive monitoring, vasoactive treatment, inotropic treatment, echocardiography, renal replacement therapy and central venous catheters based on the sex of the patient were analysed using univariate and multivariable logistic regressions. Subgroup analyses were performed on patients diagnosed with sepsis, cardiac arrest and respiratory disease. Approximately one third of the patients were women. Overall, men received more mechanical ventilation, more dialysis and more vasoactive treatment. Among patients admitted with a respiratory disease, men were more likely to receive mechanical ventilation. Furthermore, men were more likely to receive levosimendan if admitted with cardiac arrest. We conclude that differences in the level of intensive care provided to men and women still exist.

A high dose of estrogen can improve renal ischemia-reperfusion-induced pulmonary injury in ovariectomized female rats

Renal ischemia-reperfusion injury (RIRI) as a pathological process induces remote organ injury such as lung complications and it is regulated in a hormone-dependent manner. This study investigates the effect of estrogen on RIR-induced pulmonary injury in ovariectomized (OV) rats. A total of 60 female Wistar rats were divided into six groups: (i) intact sham, (ii) OV sham, (iii) OV sham + estradiol valerate (E), (iv) intact ischemia, (v) OV ischemia, and (vi) OV ischemia + E. Bilateral ischemia was performed for 45 min in all groups except sham. Before the ischemia, OV groups received an intramuscular (i.m.) injection of E. After reperfusion, blood samples were collected for serum analysis and kidney and lung tissue were separated for pathological experiment and malondialdehyde (MDA) and nitrite measurement. The left lung was weighed to measure pulmonary edema. Estrogen deficiency caused a greater increase in blood urea nitrogen and creatinine levels during IRI. Ischemia reduced nitrite of serum and lung tissue. The increased level of MDA during ischemia, returned to normal levels via estrogen injection. The severity of renal and lung damage in ischemic groups increased significantly, and estrogen improved this injury. Estrogen as an antioxidant agent can reduce oxidative stress and may improve renal function and ameliorating lung damage caused by RIR.

Mitochondrial Dysfunction in Cardiorenal Syndrome 3: Renocardiac Effect of Vitamin C

Cardiorenal syndrome (CRS) is a pathological link between the kidneys and heart, in which an insult in a kidney or heart leads the other organ to incur damage. CRS is classified into five subtypes, and type 3 (CRS3) is characterized by acute kidney injury as a precursor to subsequent cardiovascular changes. Mitochondrial dysfunction and oxidative and nitrosative stress have been reported in the pathophysiology of CRS3. It is known that vitamin C, an antioxidant, has proven protective capacity for cardiac, renal, and vascular endothelial tissues. Therefore, the present study aimed to assess whether vitamin C provides protection to heart and the kidneys in an in vivo CRS3 model. The unilateral renal ischemia and reperfusion (IR) protocol was performed for 60 min in the left kidney of adult mice, with and without vitamin C treatment, immediately after IR or 15 days after IR. Kidneys and hearts were subsequently collected, and the following analyses were conducted: renal morphometric evaluation, serum urea and creatinine levels, high-resolution respirometry, amperometry technique for NO measurement, gene expression of mitochondrial dynamic markers, and NOS. The analyses showed that the left kidney weight was reduced, urea and creatinine levels were increased, mitochondrial oxygen consumption was reduced, NO levels were elevated, and Mfn2 expression was reduced after 15 days of IR compared to the sham group. Oxygen consumption and NO levels in the heart were also reduced. The treatment with vitamin C preserved the left kidney weight, restored renal function, reduced NO levels, decreased iNOS expression, elevated constitutive NOS isoforms, and improved oxygen consumption. In the heart, oxygen consumption and NO levels were improved after vitamin C treatment, whereas the three NOS isoforms were overexpressed. These data indicate that vitamin C provides protection to the kidneys and some beneficial effects to the heart after IR, indicating it may be a preventive approach against cardiorenal insults.

Glucose Metabolic Alteration of Cerebral Cortical Subareas in Rats with Renal Ischemia/Reperfusion Based on Small-Animal Positron Emission Tomography

OBJECTIVE

To investigate glucose metabolic alterations in cerebral cortical subareas using ¹⁸F-labeled glucose derivative fluorodeoxyglucose (FDG) micro-positron emission tomography (PET) scanning in a rat renal ischemia/reperfusion (RIR) model.

METHODS

Small-animal PET imaging in vivo was performed with ¹⁸F-labeled FDG as a PET tracer to identify glucose metabolic alterations in cerebral cortical subregions using a rat model of RIR.

RESULTS

We found that the average standardized uptake value (SUV_average) of the cerebral cortical subareas in the RIR group was significantly increased compared to the sham group (P<0.05). We also found that glucose uptake in different cortical subregions including the left auditory cortex, right medial prefrontal cortex, right para cortex, left retrosplenial cortex, right retrosplenial cortex, and right visual cortex was significantly increased in the RIR group (P<0.05), but there was no significant difference in the SUV_average of right auditory cortex, left medial prefrontal cortex, left para cortex, and left visual cortex between the two groups.

CONCLUSION

The ¹⁸F-FDG PET data suggests that RIR causes a profound shift in the metabolic machinery of cerebral cortex subregions.

Xiaoyu Xiezhuo Drink Protects against Ischemia-Reperfusion Acute Kidney Injury in Aged Mice through Inhibiting the TGF-β1/Smad3 and HIF1 Signaling Pathways

Acute kidney injury (AKI) is responsible for significant mortality among hospitalized patients that is especially troubling aged people. An effective self-made Chinese medicine formula, Xiaoyu Xiezhuo Drink (XXD), displayed therapeutic effects on AKI. However, the compositions and underlying mechanisms of XXD remain to be elucidated. In this study, we used the ultra-high-performance liquid chromatography method coupled with hybrid triple quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) to investigate the chemical components in XXD. Then, the absorbable components of XXD were identified based on the five principles and inputted into the SwissTargetPrediction and STITCH databases to identify the drug targets. AKI-related targets were collected from the GenCLiP 3, GeneCards, and DisGeNET databases. The crossover genes of XXD and AKI were identified for functional enrichment analysis. The protein-protein interaction (PPI) network of crossover genes was constructed, followed by the identification of hub genes. Subsequently, the effects and potential mechanisms of XXD on AKI predicted by the network pharmacology and bioinformatics analyses were experimentally validated in ischemia-reperfusion (I/R) injury-induced AKI aged mouse models. A total of 122 components in XXD were obtained; among them, 58 components were found that could be absorbed in the blood. There were 800 potential drug targets predicted from the 58 absorbable components in AKI which shared 36 crossover genes with AKI-related targets. The results of functional enrichment analysis indicated that crossover genes mostly associated with the response to oxidative stress and the HIF1 signaling pathway. In the PPI network analysis, 12 hub genes were identified, including ALB, IL-6, TNF, TP53, VEGFA, PTGS2, TLR4, NOS3, EGFR, PPARG, HIF1A, and HMOX1. In AKI aged mice, XXD prominently alleviated I/R injury-induced renal dysfunction, abnormal renal pathological changes, and cellular senescence, inflammation, and oxidative damage with a reduction in the expression level of the inflammatory mediator, α-SMA, collagen-1, F4/80, TP53, VEGFA, PTGS2, TLR4, NOS3, EGFR, PPARG, HIF1A, ICAM-1, TGF-β1, Smad3, and p-Smad3 and an increase of nephridial tissue p-H3, Ki67, HMOX1, MMP-9, and Smad7 levels. In summary, our findings suggest that XXD has renoprotective effects against AKI in aged mice via inhibiting the TGF-β1/Smad3 and HIF1 signaling pathways.

Umbelliferone attenuates glycerol-induced myoglobinuric acute kidney injury through peroxisome proliferator-activated receptor-γ agonism in rats

Rhabdomyolysis is a clinical syndrome caused by damage to skeletal muscle, which consequently releases breakdown products into circulation and causes acute kidney injury (AKI) in humans. Intramuscular injection of glycerol mimics rhabdomyolysis and associated AKI. In this study, we explored the role of umbelliferone against glycerol-induced AKI in rats. Kidney function was assessed by measuring serum creatinine, urea, electrolytes, and microproteinuria. Renal oxidative stress was quantified using thiobarbituric acid reactive substances, superoxide anion generation, and reduced glutathione assay. Renal histological changes were determined using periodic acid Schiff and hematoxylin-eosin staining, and immunohistology of apoptotic markers (Bax, Bcl-2) was done. Serum creatine kinase was quantified to assess glycerol-induced muscle damage. Umbelliferone attenuated glycerol-induced change in biochemical parameters, oxidative stress, histological alterations, and renal apoptosis. Pretreatment with bisphenol A diglycidyl ether, a peroxisome proliferator-activated receptor-γ (PPAR-γ) antagonist, attenuated umbelliferone-mediated protection. It is concluded that umbelliferone attenuates glycerol-induced AKI possibly through PPAR-γ agonism in rats.

Betaine attenuates sodium arsenite-induced renal dysfunction in rats

Exposure to higher levels of arsenic is a serious threat affecting human health worldwide. We investigated the protective role of betaine (N,N,N-trimethylglycine) against sodium arsenite-induced renal dysfunction in rats. Sodium arsenite (5 mg/kg, oral) was given to rats for 4 weeks to induce nephrotoxicity. Betaine (125 and 250 mg/kg, oral) was administered in rats for 4 weeks along with sodium-arsenite feeding. Arsenic-induced renal dysfunction was demonstrated by measuring serum creatinine, creatinine clearance, urea, uric acid, potassium, fractional excretion of sodium, and microproteinuria. Oxidative stress in rat kidneys was determined by assaying thiobarbituric acid reactive substances, superoxide anion generation, and reduced glutathione levels. Furthermore, hydroxyproline assay was done to assess renal fibrosis in arsenic intoxicated rats. Hematoxylin-eosin and picrosirius red staining revealed pathological alterations in rat kidneys. Renal endothelial nitric oxide synthase (eNOS) expression was determined by immuno-histochemistry. Concurrent administration of betaine abrogated arsenic-induced renal biochemical and histological changes in rats. Betaine treatment significantly attenuated arsenic-induced decrease in renal eNOS expression. In conclusion, betaine is protective against sodium arsenite-induced renal dysfunction, which may be attributed to its anti-oxidant activity and modulation of renal eNOS expression in rat kidneys.

Nitric oxide synthesis stimulated by arachidonic acid accumulation via PPARα in acetylcholine-stimulated gastric mucous cells

NEW FINDINGS

What is the central question of this study? Arachidonic acid (AA) stimulates NO production in antral mucous cells without any increase in [Ca²⁺ ]_i . Given that the intracellular AA concentration is too low to measure, the relationship between AA accumulation and NO production remains uncertain. Is AA accumulation a key step for NO production? What is the main finding and its importance? We demonstrated that AA accumulation is a key step for NO production. The amount of AA released could be measured using fluorescence-HPLC. The intracellular AA concentration was maintained at < 1 μM. Nitric oxide is produced by AA accumulation in antral mucous cells, not as a direct effect of [Ca²⁺ ]_i .

ABSTRACT

In the present study, we demonstrate that NO production is stimulated by an accumulation of arachidonic acid (AA) mediated via peroxisome proliferation-activated receptor α (PPARα) and that the NO produced enhances Ca²⁺ -regulated exocytosis in ACh-stimulated antral mucous cells. The amount of AA released from the antral mucosa, measured by fluorescence high-performance liquid chromatography (F-HPLC), was increased by addition of ionomycin (10 μM) or ACh, suggesting that AA accumulation is stimulated by an increase in [Ca²⁺ ]_i . The AA production was inhibited by an inhibitor of cytosolic phospholipase A2 (cPLA2-inhα). GW6471 (a PPARα inhibitor) and cPLA2-inhα inhibited NO synthesis stimulated by ACh. Moreover, indomethacin, an inhibitor of cyclooxygenase, stimulated AA accumulation and NO production. However, acetylsalicylic acid did not stimulate AA production and NO synthesis. An analogue of AA (AACOCF3) alone stimulated NO synthesis, which was inhibited by GW6471. In antral mucous cells, indomethacin enhanced Ca²⁺ -regulated exocytosis by increasing NO via PPARα, and the enhancement was abolished by GW6471 and cPLA2-inhα. Thus, AA produced via PLA2 activation is the key step for NO synthesis in ACh-stimulated antral mucous cells and plays important roles in maintaining antral mucous secretion, especially in Ca²⁺ -regulated exocytosis.

Sex Differences in Renal Function: Participation of Gonadal Hormones and Prolactin

Kidney pathophysiology is influenced by gender. Evidence suggests that kidney damage is more severe in males than in females and that sexual hormones contribute to this. Elevated prolactin concentration is common in renal impairment patients and is associated with an unfavorable prognosis. However, PRL is involved in the osmoregulatory process and promotes endothelial proliferation, dilatation, and permeability in blood vessels. Several proteinases cleavage its structure, forming vasoinhibins. These fragments have antagonistic PRL effects on endothelium and might be associated with renal endothelial dysfunction, but its role in the kidneys has not been enough investigated. Therefore, the purpose of this review is to describe the influence of sexual dimorphism and gonadal hormones on kidney damage, emphasizing the role of the hormone prolactin and its cleavage products, the vasoinhibins.

DNA demethylase Tet2 suppresses cisplatin-induced acute kidney injury

Demethylase Tet2 plays a vital role in the immune response. Acute kidney injury (AKI) initiation and maintenance phases are marked by inflammatory responses and leukocyte recruitment in endothelial and tubular cell injury processes. However, the role of Tet2 in AKI is poorly defined. Our study determined the degree of renal tissue damage associated with Tet2 gene expression levels in a cisplatin-induced AKI mice model. Tet2-knockout (KO) mice with cisplatin treatment experienced severe tubular necrosis and dilatation, inflammation, and AKI markers' expression levels than the wild-type mice. In addition, the administration of Tet2 plasmid protected Tet2-KO mice from cisplatin-induced nephrotoxicity, but not Tet2-catalytic-dead mutant. Tet2 KO was associated with a change in metabolic pathways like retinol, arachidonic acid, linolenic acid metabolism, and PPAR signaling pathway in the cisplatin-induced mice model. Tet2 expression is also downregulated in other AKI mice models and clinical samples. Thus, our results indicate that Tet2 has a renal protective effect during AKI by regulating metabolic and inflammatory responses through the PPAR signaling pathway.

Propofol ameliorates renal ischemia/reperfusion injury by enhancing macrophage M2 polarization through PPARγ/STAT3 signaling

Propofol (Pro) confers protection against renal ischemia/reperfusion (rI/R) injury through incompletely characterized mechanisms. Since Pro has shown net anti-inflammatory properties as part of its beneficial effects, we examined the potential role of Pro in the modulation of macrophage polarization status during both rI/R injury in vivo and exposure of cultured peritoneal macrophages (PMs) to hypoxia/reoxygenation (H/R). Rats were subjected to 45-min r/IR surgery or a sham procedure and administered PBS (vehicle) or Pro during the ischemia stage. Pro administration attenuated rI/R-induced kidney damage and renal TNF-α, IL-6, and CXCL-10 expression. Enhanced macrophage M2 polarization, evidenced by reduced iNOS and increased Arg1 and Mrc1 mRNA levels, was further detected after Pro treatment both in the kidney, after rI/R in vivo, and in H/R-treated PMs. Pro administration also repressed phosphorylated signal transducer and activator of transcription 1 (p-STAT1) and increased p-STAT3, p-STAT6, and peroxisome proliferator-activated receptor-γ (PPARγ) mRNA levels in H/R-exposed PMs. Importantly, siRNA-mediated PPARγ silencing repressed Pro-mediated STAT3 activation in PMs and restored proinflammatory cytokine levels and prevented macrophage M2 marker expression in both rI/R-treated rats and cultured PMs. These findings suggest that Pro confers renoprotection against rI/R by stimulating PPARγ/STAT3-dependent macrophage conversion to the M2 phenotype.

Ameliorative Role of Diallyl Disulfide Against Glycerol-induced Nephrotoxicity in Rats

Introduction:

This study investigated the role of diallyl disulfide (DADS) against glycerol-induced nephrotoxicity in rats. Moreover, the role of peroxisome proliferator activated receptor-γ (PPAR-γ) in DADS-mediated renoprotection has been explored.

Materials and Methods:

Male Wistar albino rats were challenged with glycerol (50% w/v, 8 mL/kg intramuscular) to induce nephrotoxicity. Kidney injury was quantified by measuring serum creatinine, creatinine clearance, urea, potassium, fractional excretion of sodium, and microproteinuria in rats. Renal oxidative stress was measured in terms of thiobarbituric acid reactive substances, superoxide anion generation, and reduced glutathione levels. Hematoxylin–eosin (H&E) and periodic acid Schiff staining of renal samples was done to show histological changes. Glycerol-induced muscle damage was quantified by assaying creatine kinase (CK) levels in rat serum.

Results:

Administration of glycerol resulted in muscle damage as reflected by significant rise in CK levels in rats. Glycerol intoxication led kidney damage was reflected by significant change in renal biochemical parameters, renal oxidative stress and histological changes in rat kidneys. Administration of DADS attenuated glycerol-induced renal damage. Notably, pretreatment with bisphenol A diglycidyl ether, a PPAR-γ antagonist, abolished DADS renoprotection in rats.

Conclusion:

We conclude that DADS affords protection against glycerol-induced renal damage in rats. Moreover, PPAR-γ plays a key role in DADS-mediated renoprotective effect.

Ameliorative role of inducible nitric oxide synthase inhibitors against sodium arsenite-induced renal and hepatic dysfunction in rats

Arsenic exposure causes immense health distress by increasing risk of cardiovascular abnormalities, diabetes mellitus, neurotoxicity, and nephrotoxicity. The present study explored the role of inducible nitric oxide synthase (iNOS) inhibitors against sodium arsenite-induced renal and hepatic dysfunction in rats. Female Sprague Dawley rats were subjected to arsenic toxicity by administering sodium arsenite (5 mg/kg/day, oral) for 4 weeks. The iNOS inhibitors, S-methylisothiourea (10 mg/kg, i.p.) and aminoguanidine (100 mg/kg, i.p.) were given one hour before sodium arsenite administration in rats for 4 weeks. Sodium arsenite led rise in serum creatinine, urea, uric acid, electrolytes (potassium, fractional excretion of sodium), microproteinuria, and decreased creatinine clearance (p < 0.001) indicated renal dysfunction in rats. Arsenic-intoxication resulted in significant oxidative stress in rat kidneys, which was measured in terms of increase in lipid peroxides, superoxide anion generation and decrease in reduced glutathione (p < 0.001) levels. A threefold increase in renal hydroxyproline level in arsenic intoxicated rats indicated fibrosis. Hematoxylin-eosin staining indicated tubular damage, whereas picrosirius red staining highlighted collagen deposition in rat kidneys. S-methylisothiourea and aminoguanidine improved renal function and attenuated arsenic led renal oxidative stress, fibrosis, and decreased the kidney injury score. Additionally, arsenite-intoxication resulted in significant rise in hepatic parameters (serum aspartate aminotransferase, alanine transferase, alkaline phosphatase, and bilirubin (p < 0.001) along with multi-fold increase in oxidative stress, fibrosis and liver injury score in rats, which was significantly (p < 0.001) attenuated by concurrent administration of iNOS inhibitors). Hence, it is concluded that iNOS inhibitors attenuate sodium arsenite-induced renal and hepatic dysfunction in rats.

PPARγ in Ischemia-Reperfusion Injury: Overview of the Biology and Therapy

Ischemia-reperfusion injury (IRI) is a complex pathophysiological process that is often characterized as a blood circulation disorder caused due to various factors (such as traumatic shock, surgery, organ transplantation, burn, and thrombus). Severe metabolic dysregulation and tissue structure destruction are observed upon restoration of blood flow to the ischemic tissue. Theoretically, IRI can occur in various tissues and organs, including the kidney, liver, myocardium, and brain, among others. The advances made in research regarding restoring tissue perfusion in ischemic areas have been inadequate with regard to decreasing the mortality and infarct size associated with IRI. Hence, the clinical treatment of patients with severe IRI remains a thorny issue. Peroxisome proliferator-activated receptor γ (PPARγ) is a member of a superfamily of nuclear transcription factors activated by agonists and is a promising therapeutic target for ameliorating IRI. Therefore, this review focuses on the role of PPARγ in IRI. The protective effects of PPARγ, such as attenuating oxidative stress, inhibiting inflammatory responses, and antagonizing apoptosis, are described, envisaging certain therapeutic perspectives.

Entacapone scavenges peroxynitrite and protects against kidney and liver injuries induced by renal ischemia/reperfusion in rats

BACKGROUND

Acute kidney injury (AKI), secondary to renal ischemia/reperfusion (I/R), is a serious problem associated with high mortality. The pathophysiology of AKI after renal I/R involves peroxynitrite production; hence, scavenging this metabolite may rescue AKI. Entacapone is a catechol-O-methyl transferase (COMT) inhibitor which elicits antioxidant activity by scavenging peroxynitrite. Therefore, we hypothesized that the peroxynitrite scavenging activity of entacopone protects against AKI after renal I/R injury in rats.

METHODS

Male Wistar rats were given either entacapone or a well-known peroxynitrite scavenger (FeTPPS) daily for 10 days before I/R procedures. I/R was induced by occluding both renal pedicles for 45 min followed by reperfusion for 24 h.

RESULTS

Pre-treatment with either entacapone or FeTPPS improved renal function as indicated by a significant reduction in serum creatinine and urea when compared to I/R group (P < 0.05). I/R injury increased renal levels of NO (4-folds, P < 0.05), iNOS (4-folds, P < 0.05), and 3-nitrotyrosine (5-folds, P < 0.05) compared to sham control. These effects were abrogated in animals pre-treated with entacapone or FeTPPS before being subjected to I/R (P < 0.05). In addition, entacapone or FeTPPS significantly inhibited I/R-induced elevation in renal TNF-α levels (78% and 58%, respectively) and caspase-3 activity (72% and 56%, respectively) indicating the reduction of both inflammation and apoptosis in the kidney (P < 0.05). The two drugs also improved kidney and liver functions in rats with renal I/R injury.

CONCLUSION

Our study showed that entacapone and FeTPPS protected against AKI and remote liver damage associated with renal I/R and this effect might be due to scavenging peroxynitrite and reducing nitrosative stress.

Ameliorative role of bosentan, an endothelin receptor antagonist, against sodium arsenite-induced renal dysfunction in rats

Arsenic exposure is well documented to cause serious health hazards, such as cardiovascular abnormalities, neurotoxicity and nephrotoxicity. In the present study, we intended to explore the role of bosentan, an endothelial receptor antagonist, against sodium arsenite-induced nephrotoxicity and hepatotoxicity in rats. Sodium arsenite (5 mg/kg, oral) was administered for 4 weeks to induce renal dysfunction in rats. Sodium arsenite intoxicated rats were treated with bosentan (50 and 100 mg/kg, oral) for 4 weeks. Arsenic led renal damage was demonstrated by significant increase in serum creatinine, urea, uric acid, potassium, fractional excretion of sodium, microproteinuria and decreased creatinine clearance in rats. Sodium arsenite resulted in marked oxidative stress in rat kidneys as indicated by profound increase in lipid peroxides, and superoxide anion generation alongwith decrease in reduced glutathione levels. Hydroxyproline assay highlighted arsenic-induced renal fibrosis in rats. Hematoxylin-eosin staining indicated glomerular and tubular changes in rat kidneys. Picrosirius red staining highlighted collagen deposition in renal tissues of arsenic treated rats. Immunohistological results demonstrated the reduction of renal eNOS expression in arsenic treated rats. Notably, treatment with bosentan attenuated arsenic-induced renal damage and resisted arsenic-led reduction in renal eNOS expression. In addition, sodium arsenite-induced alteration in hepatic parameters (serum aspartate aminotransferase, alanine transferase, alkaline phosphatase, bilirubin), oxidative stress and histological changes were abrogated by bosentan treatment in rats. Hence, we conclude that bosentan treatment attenuated sodium arsenite-induced oxidative stress, fibrosis and reduction in renal eNOS expression in rat kidneys. Moreover, bosentan abrogated arsenic led hepatic changes in rats.

Stevioside protects against rhabdomyolysis-induced acute kidney injury through PPAR-γ agonism in rats

We explored the potential role of peroxisome proliferator activated receptor-γ (PPAR-γ) in stevioside-mediated renoprotection using rhabdomyolysis-induced acute kidney injury (AKI) model in rats. Rhabdomyolysis refers to intense skeletal muscle damage, which further causes AKI. Glycerol (50% w/v, 8 ml/kg) was injected intramuscularly in rats to induce rhabdomyolysis. After 24 hr, AKI was demonstrated by quantifying serum creatinine, urea, creatinine clearance, microproteinuria, and electrolytes in rats. Further, oxidative stress was measured by assaying thiobarbituric acid reactive substances, generation of superoxide anion, and reduced glutathione levels. Additionally, serum creatine kinase (CK) level was assayed to determine glycerol-induced muscle damage in rats. Pathological changes in rat kidneys were studied using hematoxylin-eosin and periodic acid Schiff staining. Moreover, the expression of apoptotic markers (Bcl-2, Bax) in rat kidneys was demonstrated by immunohistochemistry. Stevioside (10, 25, and 50 mg/kg) was administered to rats, prior to the induction of AKI. In a separate group, bisphenol A diglycidyl ether (BADGE, 30 mg/kg), a PPAR-γ receptor antagonist was given prior to stevioside administration, which was followed by rhabdomyolysis-induced AKI in rats. The significant alteration in biochemical and histological parameters in rats indicated AKI, which was attenuated by stevioside treatment. Pretreatment with BADGE abrogated stevioside-mediated renoprotection, which is suggestive of the involvement of PPAR-γ in its renoprotective effect. In conclusion, stevioside protects against rhabdomyolysis-induced AKI, which may be attributed to modulation of PPAR-γ expression.

Estrogen and estrogen receptors in kidney diseases

Acute kidney injury (AKI) and chronic kidney disease (CKD) are posing great threats to global health within this century. Studies have suggested that estrogen and estrogen receptors (ERs) play important roles in many physiological processes in the kidney. For instance, they are crucial in maintaining mitochondrial homeostasis and modulating endothelin-1 (ET-1) system in the kidney. Estrogen takes part in the kidney repair and regeneration via its receptors. Estrogen also participates in the regulation of phosphorus homeostasis via its receptors in the proximal tubule. The ERα polymorphisms have been associated with the susceptibilities and outcomes of several renal diseases. As a consequence, the altered or dysregulated estrogen/ERs signaling pathways may contribute to a variety of kidney diseases, including various causes-induced AKI, diabetic kidney disease (DKD), lupus nephritis (LN), IgA nephropathy (IgAN), CKD complications, etc. Experimental and clinical studies have shown that targeting estrogen/ERs signaling pathways might have protective effects against certain renal disorders. However, many unsolved problems still exist in knowledge regarding the roles of estrogen and ERs in distinct kidney diseases. Further research is needed to shed light on this area and to enable the discovery of pathway-specific therapies for kidney diseases.

Acute Kidney Injury in Pediatric Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a common complication of type 1 and 2 diabetes and often presents during adolescence and young adulthood. Given the growing incidence of both type 1 and type 2 diabetes in children and adolescents, DKD represents a significant public health problem. Acute kidney injury (AKI) in youth with diabetes is strongly associated with risk of DKD development. This review will summarize the epidemiology and pathophysiology of AKI in children with diabetes, the relationship between AKI and DKD, and the potential therapeutic interventions. Finally, we will appraise the impact of the recent COVID-19 infection pandemic on AKI in children with diabetes.

Nitric Oxide Mediates Inflammation in Type II Diabetes Mellitus through the PPARγ/eNOS Signaling Pathway

Inflammation accounts for the process of type II diabetes mellitus (T2DM), the specific mechanism of which is still to be elucidated yet. Nitric oxide (NO), a critical inflammation regulator, the role of which is the inflammation of T2DM, is rarely reported. Therefore, our study is aimed at exploring the effect of NO on the inflammation in T2DM and the corresponding mechanism. We analyzed the NO levels in plasma samples from T2DM patients and paired healthy adults by Nitric Oxide Analyzer then measured the expression of inflammatory cytokines (C-reactive protein, heptoglobin, IL-1β, TNF-α, IL-6) in insulin-induced HepG2 cells treated with NO donor or NO scavenger, and the PPARγ, eNOS, C-reactive protein, heptoglobin, IL-1β, TNF-α, and IL-6 levels were detected by RT-PCR and western blot in insulin-induced HepG2 cells transfected with si-PPARγ. The results showed that excess NO increased the inflammation marker levels in T2DM, which is activated by the PPARγ/eNOS pathway. These findings will strengthen the understanding of NO in T2DM and provide a new target for the treatment of T2DM.

Fenofibrate attenuates ischemia reperfusion-induced acute kidney injury and associated liver dysfunction in rats

Ischemia/reperfusion (I/R) is one of the common reasons for acute kidney injury (AKI) and we need to develop effective therapies for treating AKI. We investigated the role of fenofibrate against I/R-induced AKI and associated hepatic dysfunction in rats. In male wistar albino rats, renal pedicle occlusion for 40 min and 24 h reperfusion resulted in AKI. I/R-induced AKI was demonstrated by measuring serum creatinine, creatinine clearance, urea, uric acid, potassium, fractional excretion of sodium and urinary microproteins. Oxidative stress in rat kidneys was quantified by assaying superoxide anion generation, thiobarbituric acid reactive substances, and reduced glutathione levels. AKI-induced hepatic damage was quantified by assaying serum aminotransferases, alkaline phosphatase and bilirubin levels. Moreover, serum cholesterol, high density lipoprotein and triglycerides were quantified. Hematoxylin-eosin staining of renal and hepatic tissues was done and the kidney and liver injury scores were determined. Immunohistology of endothelial nitric oxide synthase (eNOS) was done in rat kidneys. Fenofibrate was administered for 1 week before subjecting rats to AKI. In separate group, the nitric oxide synthase inhibitor, L-nitroarginine methyl ester (L-NAME) was administered prior to fenofibrate treatment. In I/R group, significant alteration in the serum/urine parameters indicated AKI and hepatic dysfunction along with marked increase in kidney and liver injury scores. Treatment with fenofibrate attenuated AKI and associated hepatic dysfunction. Moreover, I/R-induced decrease in renal eNOS expression was abrogated by fenofibrate. Pre-treatment with L-NAME abolished fenofibrate mediated reno- and hepato-protective effects. In conclusion, fenofibrate attenuates I/R-induced AKI and associated hepatic dysfunction putatively through modulation of eNOS expression.

A single dose of estrogen during hemorrhagic shock protects against Kidney Injury whereas estrogen restoration in ovariectomized mice is ineffective

The protective effect of estrogens against chronic glomerular diseases is admitted but remains debated during acute kidney injury (AKI). Using a model of resuscitated hemorrhagic shock in C57/Bl6 female mice, this study evaluated at 1 and 21 days the renal effect of (1) endogenous estrogen, using ovariectomized mice with or without chronic estrogen restoration, or (2) exogenous estrogen, using a single administration of a pharmacological dose during shock resuscitation. In both ovariectomized and intact mice, hemorrhagic shock induced epithelial cell damages (assessed by KIM-1 renal expression) with secondary renal fibrosis but without significant decrease in GFR at day 21. Ovariectomy with or without estrogen restoration have no significant effect on renal damages and dysfunction. This lack of effect was associated with a marked (> 80%) reduction of total kidney GPR30 expression. By contrast, a single high dose of estradiol in intact mice reduced renal KIM-1 expression by 2/3, attenuated the severity of cell death related to pyroptosis, and prevented the increase of fibrosis by 1/3. This provides a rationale to investigate the benefits of a single administration of estrogen or estrogen modulators during acute kidney injuries in males. Furthermore, the cost/benefit ratio of such administration should be investigated in Human.

The Role of Vaccinium Myrtillus in the Prevention of Renal Injury in an Experimental Model of Ruptured Abdominal Aortic Aneurysm

Objective

To examine the biochemical and histopathological renal effects of ischemia/reperfusion (I/R) injury using a ruptured abdominal aortic aneurysm (RAAA) model in rats and to investigate the potential protective effects of whortleberry (Vaccinium myrtillus).

Methods

Thirty-two male Sprague-Dawley rats were randomly assigned into four groups - control, sham (I/R+glycerol), I/R, and I/R+whortleberry. Midline laparotomy alone was performed in the control group. Atraumatic abdominal clamps were attached under anesthesia to the abdominal aorta beneath the level of the renal artery in the groups subjected to I/R. Sixty-minute reperfusion was established one hour after ischemia. The sham group received five intraperitoneal doses of glycerol five days before I/R. The I/R+whortleberry group received a single intraperitoneal 50 mg/kg dose diluted with saline solution five days before I/R. All animals were finally euthanized by cervical dislocation following 60-min reperfusion.

Results

Increases were observed in malondialdehyde (MDA) levels and tubular necrosis scores (TNS) in thin kidney tissues and in numbers of apoptotic renal tubule cells, together with a decrease in glutathione (GSH) levels, in sham and I/R groups. In contrast, we observed a decrease in MDA levels, TNS, and numbers of apoptotic renal tubule cells, and an increase in GSH levels with whortleberry treatment compared to the I/R group.

Conclusion

Our findings suggest that whortleberry may be effective against acute kidney injury by reducing oxidative stress and apoptosis.

Catalpol ameliorates doxorubicin-induced inflammation and oxidative stress in H9C2 cells through PPAR-γ activation

Drug-induced cardiomyopathy is a severe disease that leads to refractory heart disease at late stages, with increasing detrimental effects. DOX-induced cell damage is primarily induced via cellular oxidative stress. The present study investigated the effects of catalpol on doxorubicin (DOX)-induced H9C2 cardiomyocyte inflammation and oxidative stress. The Cell Counting Kit-8 assay was performed to detect cell viability, and western blotting was performed to detect the expression of peroxisome proliferator-activated receptor (PPAR)-γ in H9C2 cells. The expression levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6 were measured using ELISAs. Furthermore, the oxidative stress kit was used to detect the levels of malondialdehyde, superoxide dismutase and glutathione peroxidase. A reactive oxygen species (ROS) kit and DCF-DA staining were used to detect ROS levels. The results indicated that DOX treatment inhibited H9C2 cell expression of PPAR-γ and decreased H9C2 cell viability. Various concentrations of catalpol exhibited a less potent effect on H9C2 cell viability compared with DOX; however, catalpol increased the viability of DOX-induced H9C2 cells. Catalpol treatment also significantly decreased the expression levels of inflammatory factors (TNF-α, IL-1β and IL-6) in DOX-induced H9C2 cells, which was reversed by transfections with short hairpin RNA targeting PPAR-γ. Results from the present study indicated that catalpol ameliorated DOX-induced inflammation and oxidative stress in H9C2 cardiomyoblasts by activating PPAR-γ.

Bergenin Exerts Hepatoprotective Effects by Inhibiting the Release of Inflammatory Factors, Apoptosis and Autophagy via the PPAR-γ Pathway

Objective

Hepatic ischemia reperfusion (IR) limits the development of liver transplantation technology. The aim of this study was to explore the protective effects of Bergenin on hepatic IR, particularly the elimination of reactive oxygen species (ROS) and activation of the peroxisome proliferators activated receptor γ (PPAR-γ) pathway.

Methods

Initial experiments were performed to confirm the non-toxicity of Bergenin. Mice were randomly divided into sham, IR, and IR + Bergenin (10, 20 and 40 mg/kg) groups, and serum and tissue samples were obtained at 2, 8 and 24 h for detection of liver enzymes (ALT and AST), inflammatory factors (TNF-α, IL-6 and IL-1β), ROS, cell death markers (Bcl-2, Bax, Beclin-1 and LC3) and related important pathways (PPAR-γ, P38 MAPK, NF-κB p65 and JAK2/STAT1).

Results

Bergenin reduced the release of ROS, down-regulated inflammatory factors, and inhibited apoptosis and autophagy. Additionally, expression of PPAR-γ-related genes was increased and phosphorylation of P38 MAPK, NF-κB p65 and JAK2/STAT1-related proteins was decreased in Bergenin pre-treatment groups in a dose-dependent manner.

Conclusion

Bergenin exerts hepatic protection by eliminating ROS, affecting the release of inflammatory factors, and influencing apoptosis- and autophagy-related genes via the PPAR-γ pathway in this model of hepatic IR injury.