Preventing contrast-induced nephropathy (CIN) with herbal medicines: A review

Evaluation of pathways involved in the protective effect of trans sodium crocetinate against contrast-induced nephropathy in rats

Contrast-induced nephropathy (CIN) is the most important side effect following contrast media application. The purpose of this study was to investigate the nephroprotective effects of trans sodium crocetinate (TSC) against sodium amidotrizoate/meglumine amidotrizoate (SAMA). Wistar rats were classified into eight groups (n = 6, male, 220-250 g) including (1) sham, injection of solvents (intraperitoneally; i.p.), (2) premedication-control, N(ω)-nitro-L-arginine methyl ester (L-NAME, 10 mg/kg, i.p.) + indomethacin (IND, 10 mg/kg, i.p.), (3) model (L-NAME + IND + SAMA (12.5 ml/kg, i.p.)), (4-6) TSC 10, 20, and 40 mg/kg/day, 7 days, i.p., and L-NAME + IND + SAMA, (7) N-acetylcysteine (NAC, 125 mg/kg/day, 7 days, i.p.) and L-NAME + IND + SAMA, (8) TSC alone (40 mg/kg/day, 7 days, i.p.). Rats were injected with L-NAME, IND, and SAMA 40 h after water deprivation. SAMA caused the enhancement of histopathological damage in kidney tissue, biochemical factors (serum blood urea nitrogen and creatinine), and oxidative stress. Moreover, SAMA increased inflammation (TNF-α), apoptosis proteins (Caspase 3-cleaved and Bax/Bcl-2 ratio), and autophagy markers (Beclin-1 and LC3 II/I ratio). TSC declined biochemical factors and oxidative stress. Also, TSC 40 mg/kg decreased histopathological damage, inflammation, apoptosis, and autophagy markers. This study demonstrated that TSC has nephroprotective effects through anti-oxidant, anti-inflammatory, and anti-apoptotic properties, as well as regulating autophagy.

Ameliorative and protective effects of coenzyme Q10 against natural and chemical toxicity: a narrative review

Coenzyme Q10 (CoQ10) or ubiquinone is the most known dietary and nutritional supplementation, which has various functions in the body such as involvement in adenosine triphosphate production, modulation of gene expression, antioxidant, and anti-inflammatory effects. It has been indicated that it is useful against cardiotoxicity, hepatotoxicity, neurotoxicity, nephrotoxicity, and so on, which are induced by various toxicants. In this review, we selected articles that include the protective effects of CoQ10 against the toxicity of various chemical and natural compounds including pharmaceuticals, metals, pesticides, etc. Scientific databases including PubMed/Medline, Science Direct, Scopus, and Google Scholar were searched to find relevant in vitro and in vivo studies. The underlying protective mechanisms for CoQ10 against natural and chemical compound toxicity included the enhancement of antioxidant enzyme activities such as superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, and suppression of pro-inflammatory markers such as tumor necrosis factor-alpha, interleukin-1, and IL-6. Furthermore, it has anti-apoptotic potential by regulating the B-cell lymphoma, Bcl-2-associated X protein, and caspase3/9. Overall, these properties make CoQ10 a highly fascinating compound that may contribute to different aspects of health.

Berberine ameliorates contrast-induced acute kidney injury by regulating HDAC4-FoxO3a axis-induced autophagy: In vivo and in vitro

In hospitals, contrast-induced acute kidney injury (CI-AKI) is a major cause of renal failure. This study evaluates berberine's (BBR) renal protection and its potential HDAC4 mechanism. CI-AKI in rats was induced with 10 mL kg-1 ioversol. Rats were divided into five groups: Ctrl, BBR, CI-AKI, CI-AKI + BBR, and CI-AKI + Tasq. The renal function of CI-AKI rats was determined by measuring serum creatinine and blood urea nitrogen. Histopathological changes and apoptosis of renal tubular epithelial cells were observed by HE and terminal deoxynucleotidyl transferase (TdTase)-mediated dUTP-biotin nick end labeling (TUNEL) staining. Transmission electron microscopy was used to observe autophagic structures. In vitro, a CI-AKI cell model was created with ioversol-treated HK-2 cells. Treatments included BBR, Rapa, HCQ, and Tasq. Analyses focused on proteins and genes associated with kidney injury, apoptosis, autophagy, and the HDAC4-FoxO3a axis. BBR showed significant protective effects against CI-AKI both in vivo and in vitro. It inhibited apoptosis by increasing Bcl-2 protein levels and decreasing Bax levels. BBR also activated autophagy, as indicated by changes in autophagy-related proteins and autophagic flux. The study further revealed that the contrast agent ioversol increased the expression of HDAC4, which led to elevated levels of phosphorylated FoxO3a (p-FoxO3a) and acetylated FoxO3a (Ac-FoxO3a). However, BBR inhibited HDAC4 expression, resulting in decreased levels of p-FoxO3a and Ac-FoxO3a. This activation of autophagy-related genes, regulated by the transcription factor FoxO3a, played a role in BBR's protective effects. BBR, a traditional Chinese medicine, shows promise against CI-AKI. It may counteract CI-AKI by modulating HDAC4 and FoxO3a, enhancing autophagy, and limiting apoptosis.

Adult hippocampal neurogenesis: pharmacological mechanisms of antidepressant active ingredients in traditional Chinese medicine

Depression is characterized by prominent indicators and manifestations, such as anhedonia, which refers to the inability to experience pleasure, and persistent feelings of hopelessness. In clinical practice, the primary treatment approach involves the utilization of selective serotonin reuptake inhibitors (SSRIs) and related pharmacological interventions. Nevertheless, it is crucial to recognize that these agents are associated with significant adverse effects. Traditional Chinese medicine (TCM) adopts a multifaceted approach, targeting diverse components, multiple targets, and various channels of action. TCM has potential antidepressant effects. Anomalies in adult hippocampal neurogenesis (AHN) constitute a pivotal factor in the pathology of depression, with the regulation of AHN emerging as a potential key measure to intervene in the pathogenesis and progression of this condition. This comprehensive review presented an overview of the pharmacological mechanisms underlying the antidepressant effects of active ingredients found in TCM. Through examination of recent studies, we explored how these ingredients modulated AHN. Furthermore, we critically assessed the current limitations of research in this domain and proposed novel strategies for preclinical investigation and clinical applications in the treatment of depression in future.

Endogenous and Exogenous Antioxidants as Agents Preventing the Negative Effects of Contrast Media (Contrast-Induced Nephropathy)

The use of conventional contrast media for diagnostic purposes (in particular, Gd-containing and iodinated agents) causes a large number of complications, the most common of which is contrast-induced nephropathy. It has been shown that after exposure to contrast agents, oxidative stress often occurs in patients, especially in people suffering from various diseases. Antioxidants in the human body can diminish the pathological consequences of the use of contrast media by suppressing oxidative stress. This review considers the research studies on the role of antioxidants in preventing the negative consequences of the use of contrast agents in diagnostics (mainly contrast-induced nephropathy) and the clinical trials of different antioxidant drugs against contrast-induced nephropathy. Composite antioxidant/contrast systems as theranostic agents are also considered.

Incomplete Recovery from the Radiocontrast-Induced Dysregulated Cell Cycle, Adhesion, and Fibrogenesis in Renal Tubular Cells after Radiocontrast (Iohexol) Removal

Contrast-induced nephropathy (CIN) is one of the most common causes of acute kidney injury (AKI). However, management is still limited, and the cellular response to radiocontrast removal for CIN remains unclear. This study aimed to explore the latent effects of iohexol in cultured renal tubular cells with or without the removal of iohexol by medium replacement. HK2 renal tubular cells were subcultured 24 h before use in CIN experiments. Three treatment groups were established: the control, a radiocontrast (iohexol)-only group at 75 mg I/mL (I-75), and iohexol exposure for 24 h with culture medium replacement (I-75/M). Cell cycle arrest, fibrogenic mediator assays, cell viability, cell function, and cell-cycle-related protein expression were compared between groups. Iohexol induced numerous changes in HK2 renal tubular cells, such as enlarged cell shape, cell cycle arrest, increased apoptosis, and polyploidy. Iohexol inhibited the expression of cyclins, CDKs, ZO-1, and E-cadherin but conversely enhanced the expression of p21 and fibrosis-related genes, including TGF-β1, CTGF, collagen I, collagen III, and HIF-1α within 60 hr after the exposure. Except for the recovery from cell cycle arrest and cell cycle gene expression, notably, the removal of iohexol by medium replacement could not fully recover the renal tubular cells from the formation of polyploid cells, the adhesion or spreading, or the expression of fibrosis-related genes. The present study demonstrates, for the first time, that iohexol exerts latent cytotoxic effects on cultured renal tubular cells after its removal, suggesting that these irreversible cell changes may cause the insufficiency of radiocontrast reduction in CIN, which is worth investigating further.

Nature's Toolbox Against Tau Aggregation: An Updated Review of Current Research

Tau aggregation is a hallmark of several neurodegenerative disorders, such as Alzheimer's disease (AD), frontotemporal dementia, and progressive supranuclear palsy. Hyperphosphorylated tau is believed to contribute to the degeneration of neurons and the development of these complex diseases. Therefore, one potential treatment for these illnesses is to prevent or counteract tau aggregation. In recent years, interest has been increasing in developing nature-derived tau aggregation inhibitors as a potential treatment for neurodegenerative disorders. Researchers have become increasingly interested in natural compounds with multifunctional features, such as flavonoids, alkaloids, resveratrol, and curcumin, since these molecules can interact simultaneously with the various targets of AD. Recent studies have demonstrated that several natural compounds can inhibit tau aggregation and promote the disassembly of pre-formed tau aggregates. Nature-derived tau aggregation inhibitors hold promise as a potential treatment for neurodegenerative disorders. However, it is important to note that more research is needed to fully understand the mechanisms by which these compounds exert their effects and their safety and efficacy in preclinical and clinical studies. Nature-derived inhibitors of tau aggregation are a promising new direction in the research of neurodegenerative complexities. This review focuses on the natural products that have proven to be a rich supply for inhibitors in tau aggregation and their uses in neurodegenerative complexities, including AD.

Kidney Function, Male Gender, and Aneurysm Diameter Are Predictors of Acute Kidney Injury in Patients with Abdominal Aortic Aneurysms Treated Endovascularly

Abdominal aortic aneurysm (AAA) is a degenerative disease of the aortic wall with potentially fatal complications. The widespread adoption of endovascular aneurysm repair (EVAR), which is less invasive and equally (if not more) effective for abdominal aortic aneurysms (AAA), is due to the obvious advantages of the procedure compared to the traditional open repair. As the popularity of endovascular procedures grows, related complications become more evident, with kidney damage being one of them. Although acute kidney injury following EVAR is relatively common, its true incidence is still uncertain. The purpose of this study was to assess the incidence of acute kidney injury among patients treated with endovascular repair of ruptured AAA. In addition, we aimed to determine the predictors of PC-AKI in patients with abdominal aortic aneurysm treated with EVAR.

PATIENTS AND METHODS

We retrospectively analyzed a prospective registry of abdominal aortic aneurysm of 247 patients operated endovascularly at a single center between 2015 and 2021. Due to a lack of clinical data, data of 192 patients were reviewed for postcontrast acute kidney injury. Additional comorbidities were included in this study: hypertension, diabetes mellitus, atrial fibrillation, chronic coronary syndrome, COPD, and chronic kidney disease. Follow-up examinations were performed before the procedure and 48 h after contrast administration.

RESULTS

The group of 36 patients developed PC-AKI, which is 19% of the entire study population. Hypertension, diabetes, chronic kidney disease, male gender, and incidence of PC-AKI were more prevalent in patients with higher aortic aneurysm diameter ≥67 mm. In multiple regression analyses, independent predictors of PC-AKI were serum creatinine, chronic kidney disease, male gender, and aortic aneurysm diameter ≥67 mm.

CONCLUSIONS

One of the major complications after EVAR is acute kidney injury, which is linked to higher death and morbidity rates. Independent risk factors for postcontrast acute kidney injury were chronic kidney disease, male gender, and aortic diameter. Only aortic diameter could be modifiable risk factor, and earlier surgery could be considered to yield better outcomes. More research is critically needed to determine how AKI affects long-term outcomes and to look at preventive options.

Contrast-Associated Acute Kidney Injury: Advances and Challenges

A decrease in renal function that follows intravascular administration of contrast medium (CM) within a few days is reported as contrast-induced acute kidney injury (CI-AKI). In clinical practice, the imaging procedure is frequently deferred when clinicians consider that the renal risks caused by CM outweigh the benefits of enhanced imaging. However, with an in-depth understanding of AKI and contrast medium, scholars have realized that the decrease in renal function after CM is caused by contrast medium factors and noncontrast medium factors (such as anemia and hemodynamic instability). Therefore, acute kidney injury caused by CM has been overestimated in the past. The term “contrast-associated acute kidney injury (CA-AKI)” has been increasingly used to indicate AKI after intravascular administration of contrast medium compared with CI-AKI. CA-AKI can increase the risk of death and chronic kidney disease. However, its pathophysiological mechanism has not been fully elucidated, and the effectiveness of various preventive and therapeutic measures have been questioned. These present challenges for us. In this article, we will review the diagnostic criteria, epidemiology, risk factors, pathophysiological mechanisms and treatment of CA-AKI to provide optimized imaging procedures in clinical practice.

(+)-Sesamin, a sesame lignan, is a potent inhibitor of gut bacterial tryptophan indole-lyase that is a key enzyme in chronic kidney disease pathogenesis

The progression of chronic kidney disease (CKD) increases the risks of cardiovascular morbidity and end-stage kidney disease. Indoxyl sulfate (IS), which is derived from dietary l-tryptophan by the action of bacterial l-tryptophan indole-lyase (TIL) in the gut, serves as a uremic toxin that exacerbates CKD-related kidney disorder. A mouse model previously showed that inhibition of TIL by 2-aza-l-tyrosine effectively reduced the plasma IS level, causing the recovery of renal damage. In this study, we found that (+)-sesamin and related lignans, which occur abundantly in sesame seeds, inhibit intestinal bacteria TILs. Kinetic studies revealed that (+)-sesamin and sesamol competitively inhibited Escherichia coli TIL (EcTIL) with K_i values of 7 μM and 14 μM, respectively. These K_i values were smaller than that of 2-aza-l-tyrosine (143 μM). Molecular docking simulation of (+)-sesamin- (or sesamol-)binding to EcTIL predicted that these inhibitors potentially bind near the active site of EcTIL, where the cofactor pyridoxal 5'-phosphate is bound, consistent with the kinetic results. (+)-Sesamin is a phytochemical with a long history of consumption and is generally regarded as safe. Hence, dietary supplementation of (+)-sesamin encapsulated in enteric capsules could be a promising mechanism-based strategy to prevent CKD progression. Moreover, the present findings would provide a new structural basis for designing more potent TIL inhibitors for the development of mechanism-based therapeutic drugs to treat CKD.

[Effect of half-dose fluorescein sodium contrast agent on liver and kidney functions in patients with mild to moderate chronic kidney disease: a retrospective cohort study]

OBJECTIVE

To observe the effect of half-dose fluorescein sodium (FINa) contrast agent on liver and kidney functions in patients with mild to moderate (stage 1 to 3) chronic kidney disease (CKD) and the incidence of contrast-induced nephropathy (CIN).

METHODS

Seventy-seven patients (including 50 male and 27 female patients with an mean age of 53.5±9.6 years) with CKD with normal renal function or mild to moderate abnormalities underwent fundus fluorescein angiography (FFG) examination with half-dose FINa. Liver function, blood creatinine (Scr), blood urea nitrogen (BUN), urine β2 microglobulin (β2-MG), and glomerular filtration rate (eGFR) of the patients were measured within 3 days before intravenous injection of the contrast agent and at 1, 3, 7, and 30±1 days after the operation to analyze the effect of the contrast agent on renal function.

RESULTS

Among the 77 patients, CIN occurred only in one case with an incidence rate of 1.30%. BUN, urine β2- MG, or rapid microalbumin/creatinine did not vary significantly after FFA in these patients. Scr levels showed no significant increments at 1 day and 7 days after FFA, but increased significantly at 3 days (24.6±2.3; P < 0.01) and 30 days (16.0±21.7; P < 0.05). Urine NAG enzymes and urinary osmolality were significantly reduced at 1, 3, 7, and 30 days after FFA (P < 0.01). The eGFR decreased significantly to 10.23±0.62 at 3 days after FAG and became normal at 7 days. Urine albumin level decreased significantly at 1, 3, 7, and 30 days after FFA (P < 0.01). Blood β2-MGFAG level increased significantly at 3 days after FFA (0.314± 0.121; P < 0.01), but decreased to 0.134±0.143 at 7 days (P < 0.05). The level transaminase decreased significantly at 3 and 7 days after FFA (P < 0.01).

CONCLUSION

Half-dose of FINa has no significant effect on liver function and has only minimal effect on kidney function in patients with mild to moderate CKD, and FFA with half-dose FINa can therefore be safely performed in these patients.