Effects of cyclosporine on ischemia-reperfusion injuries in rat kidneys. An experimental model

Combination of Deferoxamine With Cyclosporine Synergistically Blunt Renal Cold Ischemia-Reperfusion Injury in Rat Transplantation Model

OBJECTIVES

Ferroptosis plays a pivotal role in the pathogenesis of renal ischemia-reperfusion injury, where the processes are mediated by free ferrous ions and mitochondrial-released reactive oxygen species. However, the administration of high doses of cyclosporine A (CsA) or deferoxamine (DFO) poses a significant risk of renotoxicity. In contrast, low doses of DFO act as a ferrous iron chelator, and CsA functions as a mitochondrial reactive oxygen species blocker. This study aims to explore the potential protective effects of donor treatment with low-dose CsA, DFO, or their combination against ischemia-reperfusion injury during renal transplantation in a rat model.

MATERIALS AND METHODS

In an ex vivo cold storage (CS) model utilizing renal slices, the impact of incorporating DFO, CsA, and a combination of both into the University of Wisconsin solution was assessed through the measurement of lactate dehydrogenase leakage. Additionally, their potential benefits were investigated in a rat donation after circulatory death (DCD) kidney transplant model, where the extent of damage was evaluated based on graft function, tubular necrosis, and inflammation.

RESULTS

The co-administration of DFO and CsA effectively decreased the release of lactate dehydrogenase induced by CS ( P ≥ .05). In the in vivo model, this combined supplementation demonstrated a mitigating effect on reperfusion injury, evidenced by lower blood urea nitrogen levels and acute tubular necrosis scores compared to the control group (allP ≤ .05). Furthermore, the combined treatment significantly reduced apoptotic levels compared to the control group (P ≥ .05).

CONCLUSIONS

The combined treatment with DFO and CsA mitigated the cold ischemia-reperfusion injury in the DCD kidney. Hence, this presents a new strategy for the CS of DCD kidney in clinical transplants.

The efficiency of oxerutin on apoptosis and kidney function in rats with renal ischemia reperfusion injury

BACKGROUND

Background: Renal ischemia-reperfusion injury (RIRI) is the most frequent cause of acute renal failure in clinical conditions such as trauma and shock as well as renal surgeries. Oxerutin is a member of the flavonoid family and possesses antioxidant properties. The aim of this study was to investigate whether oxerutin has protective effects on RIRI.

METHODS

Twenty-eight male Wistar albino rats were randomly divided into three groups: sham control group (n=8), RIRI group (n=10), and RIRI + oxerutin group (n=10). RIRI was achieved by clamping the left renal artery for 30 min, followed 1-h reperfusion period. Thereafter, blood samples and left kidney tissue samples were taken for histopathological and biochemical examination. Blood urea nitrogen (BUN), urea, creatinine, and cystatin C levels, which are indicators of kidney function, as well as tumor necrosis factor-alpha, which is an indicator of inflammation were analyzed in blood samples. Total antioxidant status and total oxidant status (TOS), which are indicators of oxidative stress were analyzed on renal tissues. The apoptotic index, an indicator of kidney damage, as well as histopathological changes were evaluated on renal tissues.

RESULTS

The apoptotic index, TOS, tumor necrosis factor-alpha, BUN, and urea levels were lower in the RIRI + oxerutin group than in the RIRI group (p<0.05). The results demonstrated that the histopathological and biochemical properties of oxerutin protected rats from RIRI.

CONCLUSION

The findings obtained in this study show that prophylactic administration of oxerutin has protective effects on apoptosis and renal failure caused by RIRI. Therefore, oxerutin can be used as an effective prophylactic agent in the treatment of RIRI.

Nephroprotective Efficacy of Sugammadex in Ischemia-Reperfusion Injury: An Experimental Study in a Rat Model

Background: It is known that ischemia-reperfusion damage in the kidney is one of the most common causes of acute kidney failure. It is also known that reduced renal damage has a nephroprotective effect by reducing the release of inflammatory and vasoactive peptides that cause tissue damage. Therefore, we think that reperfusion caused by ischemia in kidney damage may be an important focus for clinical research.

Methods: A total of 21 healthy 230-250 g female rats were used in our experimental study. During the experiment, animals were randomly divided into three groups, each containing seven rats. Group 1: The group that underwent left nephrectomy with a sham operation. Group 2: Left renal ischemia for 60 minutes, then left nephrectomy followed by 45 minutes of reperfusion. Group 3: Left renal ischemia for 60 minutes, then reperfusion for 45 minutes, followed by left nephrectomy. In this group, sugammadex was given intravenously at a dose of 100 mg/kg at the beginning of reperfusion. In the histomorphological examination, damage findings of tubules atrophy, dilation and cast formation, tubular epithelial brush border loss and vacuolization, presence of fibrosis as interstitial structural change, capillary vasodilatation/congestion and neutrophilic cell infiltrates in interstitial spaces, and morphological changes in glomeruli were evaluated.

Results: When evaluated based on tubular brush border, there were no significant differences between Group 2 and Group 1 (P = 0.454), while the damage in Group 3 was less significant than Group 2 (P = 0.017). When evaluated in terms of tubular vacuolization, there was no significant difference between Group 2 and Group 1 (P = 0.902), while the damage in Group 3 was less significant than Group 2 (P = 0.017).

Conclusion: We believe that 100 mg/kg sugammadex given at the beginning of reperfusion after one hour of ischemic condition on rats has a histochemically detectable nephroprotective effect.

Effects of cyclosporin A pre-treatment combined with etomidate post-treatment on lung injury induced by limb ischemia-reperfusion in rats

OBJECTIVES

To investigate the influence of cyclosporin A (CsA) pre-treatment and etomidate (ETO) post-treatment on lung injury induced by limb ischemia-reperfusion (I/R) in rats.

METHODS

Rats were randomly divided into five groups: sham, I/R, I/R+CsA, I/R+ETO, and I/R+CsA+ETO. Limb I/R lung injury was established by bilateral clamping of the femoral arteries for 2 hours. Following reperfusion for 3 hours, blood gas analysis was performed. Pathological changes were assessed using immunohistochemistry. The apoptosis index (AI) and wet/dry weight ratio (W/D) were calculated. Levels of Fas protein and FasL mRNA were assessed by western blotting and RT-PCR, respectively. Tumor necrosis factor (TNF)-α and interleukin (IL)-1β were detected by ELISA.

RESULTS

I/R resulted in decreased PaO2 but increased AI, W/D, Fas, FasL mRNA, TNF-α and IL-1β. Scattered punctate apoptosis and necrosis were observed by immunohistochemistry. Compared with the I/R group, the I/R+ETO and I/R+CsA groups showed increased SpO2, decreased AI, W/D, Fas, FasL mRNA, TNF-α and IL-1β, and decreased numbers of apoptotic and necrotic cells. Combined treatment with CsA+ETO resulted in more dramatic changes in these parameters.

CONCLUSIONS

ETO post-treatment and CsA pretreatment reduced lung injury induced by limb I/R in rats. The mechanism may be related to synergistic inhibition of Fas/FasL signaling.

Sialic acid-modified dexamethasone lipid calcium phosphate gel core nanoparticles for target treatment of kidney injury

Acute kidney injury (AKI) is a common clinical disease with high morbidity and mortality. Glucocorticoids are drugs that effectively relieve AKI, but the systemic side effects of long-term use limit their use. Herein, we constructed sialic acid-modified dexamethasone sodium phosphate (Dsp)-loaded lipid calcium phosphate gel core nanoparticles (SA-NPs) for the targeted treatment of ischemia-reperfusion (I/R)-induced AKI to improve efficacy and reduce side effects. The obtained nanoparticles could effectively encapsulate Dsp with 66.8% encapsulation efficiency and 4.56% (w/w) drug content. In vitro release indicates that the nanoparticles have a certain sustained release effect and have the characteristics of acid-sensitive release. And SA-NPs significantly increased the cellular uptake and kidney accumulation respectively through the combination of SA and E-selectin receptors overexpressed in inflamed vascular endothelial cells. Besides, the in vivo pharmacokinetic studies showed that Dsp-loaded SA-NPs significantly increased the residence time in the body and their plasma half-life was 1.7 times that of free Dsp. SA-NPs significantly improved the renal function, decreased the level of pro-inflammatory factors, and adjusted the oxidative stress factors and apoptotic proteins compared to free Dsp solution in pharmacodynamic studies. Moreover, little negative effects on blood glucose and bone mineral density were observed. Our study might provide a new strategy for the safe and effective targeting treatment of AKI or other related inflammatory diseases.