Oxidative stress-induced renal telomere shortening as a mechanism of cyclosporine-induced nephrotoxicity.

Due to the association of oxidative stress and telomere shortening, it was aimed in the present study to investigate the possibility whether cyclosporine-A exerts its nephrotoxic side effects via induction of oxidative stress-induced renal telomere shortening and senescent phenotype in renal tissues of rats. Renal oxidative stress markers, 8-hydroxydeoxyguanosine, malondialdehyde, and protein carbonyl groups were measured by standard methods. Telomere length and telomerase activity were also evaluated in kidney tissue samples. Results showed that cyclosporine-A treatment significantly (P < 0.05) enhanced renal malondialdehyde, 8-hydroxydeoxyguanosine, and protein carbonyl groups levels, decreased renal telomere length, and deteriorated renal function compared with the controls. Renal telomerase activity was not affected by cyclosporine-A. Renal telomere length could be considered as an important parameter of both oxidative stress and kidney function. Telomere shortening and accelerated kidney aging may be caused by cyclosporine-induced oxidative stress, indicating the potential mechanism of cyclosporine-induced nephrotoxicity.

The Effects of Valsartan on Renal Klotho Expression and Oxidative Stress in Alleviation of Cyclosporine Nephrotoxicity.

BACKGROUND: Nephrotoxicity side effect of the immunosuppressive drug, cyclosporine A (CsA), can be a major issue in transplantation medicine. Cyclosporine A-induced nephrotoxicity is multifactorial but oxidative stress has a critical role in this process. It has been demonstrated that Valsartan (Val) as an angiotensin receptor blocker has renoprotective effects, but the molecular mechanisms responsible for the renal protection, independent from its blood pressure lowering effect, have not yet been fully understood. The present study is aim at evaluating the Val effect in alleviation of CsA nephrotoxicity by probable increase in renal Klotho expression and/or reducing oxidative stress. METHODS: Thirty-two Sprague-Dawley rats were divided into 4 groups based on the administration of CsA and/or Val: group A (control, 1 mL/kg per day of olive oil as vehicle), group B (CsA, 30 mg/kg per day), group C (CsA + Val, 30 + 30 mg/kg per day), and group D (Val, 30 mg/kg per day). Real-time polymerase chain reaction and Western blotting were used to evaluate Renal Klotho expression. Serum Klotho level was measured by enzyme-linked immunosorbent assay. 8-Hydroxy-deoxy guanosine and malondialdehyde levels as markers of oxidative stress were measured by enzyme-linked immunosorbent assay and spectrophotometrically, respectively. RESULTS: Cyclosporine A treatment reduced renal expression and serum levels of Klotho, improved malondialdehyde and 8-hydroxy-deoxy guanosine levels, and also deteriorated renal function. Valsartan prevented CsA-induced oxidative stress as well as Klotho downregulation and could alleviate CsA-induced renal histological changes and function. CONCLUSIONS: Administration of Val might lead to amelioration of CsA nephrotoxicity by probably diminishing CsA-induced renal Klotho downregulation and oxidative stress.

Effects of Angiotensin II Receptor Blockade on Soluble Klotho and Oxidative Stress in Calcineurin Inhibitor Nephrotoxicity in Rats.

INTRODUCTION: Calcineurin inhibitor nephrotoxicity is major problem after organ transplantation. It is multifactorial, but oxidative stress may have an important role in this process. It has been shown that angiotensin II receptor blockers have renoprotective effects but their molecular mechanism is largely unknown. Antioxidative effect is an important role of the recently known anti-aging protein, klotho. This study aimed to evaluate effect of valsartan in alleviation of cyclosporine A nephrotoxicity via a probable increase in serum klotho levels or decreasing oxidative stress. MATERIALS AND METHODS: Thirty-two Sprague-Dawley rats were divided into 4 groups to receive 1 mL/kg/d of olive oil as control; 30 mg/kg/d of cyclosporine; 30 mg/kg/d of cyclosporine and 50 mg/kg/d of valsartan; and 50 mg/kg/d of valsartan. After the 6 weeks of administration period, serum levels of klotho and 8-hydroxydeoxyguanosine were measured using an enzyme-linked immunosorbent assay. Serum malondialdehyde level was measured spectrophotometrically. RESULTS: The mean serum level of klotho was significantly lower in the cyclosporine group compared with control and valsartan groups. Klotho level in the valsartan group was significantly higher than those in the other groups. The cyclosporine group was detected to have significantly higher serum 8-hydroxydeoxyguanosine and malondialdehyde levels compared with the other study groups. The levels of klotho were negatively correlated with 8-hydroxydeoxyguanosine and malondialdehyde levels. CONCLUSIONS: Administration of valsartan may lead to attenuation of the nephrotoxic side effect of cyclosporine via enhancing klotho and decreasing oxidative stress levels.

The effects of valsartan on renal glutathione peroxidase expression in alleviation of cyclosporine nephrotoxicity in rats.

Introduction: Nephrotoxicity as a side effect caused by the immunosuppressive drug, cyclosporine-A (CsA), can be a major problem in transplant medicine. Oxidative stress may play an important role in the CsA-induced nephrotoxicity. It has been shown that the antihypertensive drug, valsartan (Val), has also renoprotective effects but, its molecular mechanism is largely unknown. In the present study, it was aimed to evaluate the Val effect in the alleviation of CsA nephrotoxicity via probable renal glutathione peroxidase (GPx) upregulation and oxidative stress decrease. Methods: Thirty-two Sprague-Dawley rats were divided into four groups based on CsA and/or Val administration: group A (Control, 1 mL/kg/day of olive oil as vehicle), group B (CsA, 30 mg/kg/day), group C (CsA+Val, 30+30 mg/kg/day), and group D (Val, 30 mg/kg/day). After the administration period (six weeks), renal GPx expression was evaluated by real-time polymerase chain reaction (PCR). Plasma levels of GPx and 8-Hydroxydeoxyguanosine (8-OHdG) were measured by enzyme-linked immunosorbent assay (ELISA). Malondialdehyde (MDA) and protein carbonyl groups (PCG) were measured by spectrophotometer. Plasma levels of urea and creatinine were measured by an autoanalyzer. Results: CsA treatment led to the decrease in renal expression and plasma levels of GPx in comparison to other study groups. Rats received CsA were detected to have significantly (p<0.05) higher plasma 8-OHdG, MDA, PCG, urea, and creatinine levels in comparison to other groups. Plasma urea and creatinine levels were negatively correlated with renal GPx expression and positively correlated with the oxidative stress markers. Conclusion: Administration of Val may result in attenuating the nephrotoxic side effect of CsA via probable renal GPx upregulation, and subsequently oxidative stress decrease.

Retraction Note: The effects of valsartan on renal glutathione peroxidase expression in alleviation of cyclosporine nephrotoxicity in rats.

[This retracts the article DOI: 10.15171/bi.2016.18.].

Design and construction of immune phage antibody library against Tetanus neurotoxin: Production of single chain antibody fragments.

BACKGROUND: Tetanus neurotoxin (TeNT) is composed of a light (LC) and heavy chain (HC) polypeptides, released by anaerobic bacterium Clostridium tetani and can cause fatal life-threatening infectious disease. Toxin HC and LC modules represents receptor binding and zinc metalloprotease activity, respectively. The passive administration of animal-derived antibodies against tetanus toxin has been considered as the mainstay therapy for years. However, this treatment is associated with several adverse effects due to the presence of anti-isotype antibodies. OBJECTIVE: In the present study, we have produced the fully human single chain antibody fragments (HuScFv) from two human antibody phage display libraries. MATERIAL AND METHODS: Twenty-four different HuscFvs were isolated from two anti TeNT immune libraries. Our produced human ScFv (HuScFv) were converted to IgG platform and analyzed regarding their specific reactivity to TeNT. RESULTS: All of the selected scFvs have the same VL but different VH. Three HuscFvs from the first library (TTX15, 51, 75) and two HuscFvs from the second library (TTX16, 20) were chosen to convert to IgG1 using pOptiVEC and pcDNA3.3 systems. Production of IgG1 from transfected DG44 and binding capacity of them to tetanus toxin and toxoid were measured by ELISA. ELISA results showed no detectable production of TTX16 and TTX20 IgG1. Although, TTX51 and TTX75 were converted and produced as IgG1, no reactivity to tetanus toxin and toxoid was observed. However, TTX15 was successfully produced as whole IgG1 platform with reactivity to both tetanus toxin and toxoid. The latter would be an appropriate replacement for conventional polyclonal antibodies if would meet the further characterization including specificity determination, affinity measurement and toxin neutralizing assays. CONCLUSION: Our results demonstrated production of functional IgG1 derived from TTX15 scFv and might be an appropriate replacement for polyclonal Tetabulin but it needs further characterization.

Tissue fatty acid composition in obstructive sleep apnea and recurrent tonsillitis.

OBJECTIVE: Tonsillar hypertrophy cells appear to have an altered lipid metabolism as evidenced by modulated inflammatory cytokines that affect tissue lipid metabolism. The aim of this study was to investigate differences in tissue fat composition between obstructive sleep apnea (OSA) and recurrent infective tonsillitis (RT) in children. METHODS: Tonsillar tissues were collected from 114 patients with OSA and 92 patients with RT, aged 4-10 years, during tonsillectomy. The tissue lipid extracts were analyzed by gas liquid chromatography for a comprehensive fatty acid profile. RESULTS: In the tonsillitis tissue, the levels of palmitoleic acid (16:1n-7; P=0.002) and oleic acid (18:1n-9; P=0.003) were higher, and the level of stearic acid (18:0; P=0.004) was lower than that in the hyperplastic tonsillar tissue. Overall, tonsillar tissue of patients with RT had a significant increase in the total monounsaturated fatty acids (+9.9%; P<0.001) and the fatty acid desaturation index (+20.5%; P<0.001). Furthermore, oleic acid content of tonsillar tissue was positively correlated with BMI (r=0.20, P=0.004), snoring (r=0.16, P=0.022) and hypertrophy grade (r=0.18, P=0.023), which remain significant in the subgroup analysis by hypertrophy type. CONCLUSIONS: The change in the fatty acid composition may be regarded as an indicator of altered lipid metabolism occurring in vivo during human tonsillar hypertrophy, which might be linked to the severity or type of the tissue damage.

The effect of erythropoietin on ischemia/reperfusion injury after testicular torsion/detorsion: a randomized experimental study.

This study was conducted to investigate the protective effect of erythropoietin (EPO) on ischemia/reperfusion related changes after testicular torsion/detorsion. In a randomized experimental trial 30 male rats were randomly allocated into six equal groups of five rats each. Group I (orchiectomy for histopathologic examination), group II (sham operation), group III (torsion for 2 hours, and ischemia/detorsion for 24 hours, and orchiectomy); group IV (torsion for 2 hours, ischemia/detorsion for 24 hours with erythropoietin injection then orchiectomy), group V (torsion for 2 hours and detorsion and EPO injection and orchiectomy 1 week later, group VI (torsion for 2 hours/detorsion and orchiectomy 1 week later). Two groups (groups 4 and 5) received different protocols of erythropoietin administration after testicular torsion/distortion. other groups were not receiving erythropoietin. Johnsen's spermatogenesis scoring method and Cosentino's histologic staging method were used to assess main outcome measures of the study. After the experimentation, Johnsen's score in EPO Groups was statistically different from the score in some groups not receiving erythropoietin. Cosentino's score in EPO groups was statistically different from the score in all groups not receiving erythropoietin. Neovascularization, vascular necrosis, vascular congestion, edema, hemorrhage, and acute inflammation were observed in some groups. This study shows short-term protective efficacy of erythropoietin on rat testicular injury after ischemia/reperfusion.

Circulating phospholipase-A2 activity in obstructive sleep apnea and recurrent tonsillitis.

OBJECTIVE: Phospholipase A2 (PLA2) plays a major part in growth regulation, differentiation and inflammation. It has been proposed as an evaluating marker for infection and inflammation. The aim of this study was to investigate activity of serum type II secretory PLA2 (sPLA2 IIa) in obstructive sleep apnea (OSA) and recurrent infective tonsillitis (RT) in children. METHODS: Activity of serum sPLA2 IIa was determined in children who underwent tonsillectomy, including OSA in 126 cases and RT in 60. Serum enzyme activities were measured using the standard assay with Diheptanoyl Thio-Phosphatidylcholin as substrate. RESULTS: The sPLA2 IIa activity of serum was significantly higher in RT than in OSA (P<0.01). Serum sPLA2 IIa activity in the RT patients was positively correlated with BMI (r=0.26; P=0.02), which was not apparent in OSA (r=0.14; P=0.09). CONCLUSION: This study suggests that serum sPLA2 IIa activity may be considered as a supportive diagnostic marker in suspected or clinically unclear cases of RT children.

A neonate with cleft palate and a fetal mass in the oral cavity: a rare case of an oral fetus-in-fetu.

Fetus-in-fetu is a rare congenital condition in which a malformed fetus-like structure is found in the body of its twin. We report a unique case of a male neonate with cleft palate and a fetus-like structure arising in his oral cavity. The neonate underwent emergent surgical removal of the mass immediately after delivery. Radiological and pathological studies of the resected mass provided supportive evidence for the case of an oral fetus-in-fetu. To our knowledge, there are few cases of oral fetus-in-fetu in the literature. Moreover, the presence of cleft palate in this neonate is of potential interest and clinical importance.