Renoprotective Effects of Alpha Lipoic Acid on Iron Overload-Induced Kidney Injury in Rats by Suppressing NADPH Oxidase 4 and p38 MAPK Signaling

We aimed to investigate the protective effect of alpha lipoic acid (ALA), a powerful antioxidant, against oxidative kidney damage induced by iron overload in rats. Male Wistar albino rats were separated into groups: control (n = 7), ALA (100 mg/kg (n = 7), iron sucrose (IS) (40 mg/kg) (n = 7), and IS + ALA (40 mg/kg IS administration followed by 100 mg/kg ALA) (n = 7). IS and ALA were injected weekly for 4 weeks via the tail vein. Blood and kidneys were collected at sacrification on day 29. Serum creatinine and iron levels were analyzed. Tubular injury and iron deposits were evaluated histopathologically. Additionally, iron, malondialdehyde (MDA), superoxide dismutase (SOD), catalase, and glutathione (GSH) levels and mRNA expressions of the subunits of NADPH oxidase, known as NOX4 and p22phox, tumor necrosis factor (TNF)-α, kidney injury molecule-1 (KIM-1), and also p38 MAPK signaling in the kidneys, were evaluated biochemically. In the IS group, serum creatinine and iron level, tubular dilation, and loss of brush border in the kidneys were significantly higher than those of the control. Although those changes were reduced by ALA, the differences were not statistically significant. However, ALA reduced significantly MDA level and increased SOD activity in the kidney during IS administration. ALA also significantly reduced mRNA expressions of NOX4 and p22phox induced by IS, which was parallel to significant decreases of TNF-α and KIM-1 mRNA expressions. Moreover, ALA could suppress the activation of p38 MAPK during IS administration. In conclusion, ALA may be an effective strategy to attenuate in IS-induced oxidative kidney injury.

Pretreatment with nebivolol attenuates level and expression of matrix metalloproteinases in a rat model of renal ischaemia-reperfusion injury

AIM

Matrix metalloproteinases (MMPs) are zinc-containing proteinases that are involved in the degradation of extracellular matrix (ECM) and a number of cell surface proteins in order to maintain tissue homeostasis. They are involved in pathogenesis of several ischaemic organ injuries. In the present study, we aimed to determine the expression and level of MMP-2 and MMP-9 in renal ischaemia-reperfusion injury (IRI) model and the potential beneficial effect of nebivolol, a β1 -adrenergic receptor blocker, on both MMP-2 and -9 level and expression and tubular injury caused by IRI.

METHODS

Twenty Wistar albino rats were divided into three groups: sham-operated , ischaemia-reperfusion, and nebivolol-pretreated. IRI model was induced by bilateral clamping of renal arteries for 45 min followed by 24 h of reperfusion. The analysis of serum creatinine levels, quantity and expression of MMP-2 and MMP-9 were performed after 24 h of IRI. The effects of nebivolol on level and expression of MMP-2 and MMP-9 levels were investigated by enzyme-linked immunosorbent assay and immunohistochemistry, respectively. The pathological examinations were performed to score tubular damage by light microscopy.

RESULTS

Creatinine levels increased significantly in the ischaemia-reperfusion group compared to the sham-operated group. Rats in the nebivolol-pretreated group showed significant decrease in expression and quantity of MMP-2 and MMP-9 during IRI. The pathological examinations demonstrated significantly low level of tubular injury score in nebivolol-pretreated group.

CONCLUSION

Nebivolol attenuated IRI by decreasing the expression and level of MMP-2 and MMP-9.

Pretreatment with paricalcitol attenuates level and expression of matrix metalloproteinases in a rat model of renal ischemia-reperfusion injury

BACKGROUND

Ischemia-reperfusion injury (IRI) is a leading cause of acute kidney injury (AKI). The inflammatory response that drives IRI involves upregulation of matrix metalloproteinases (MMPs), which results in proteolytic degradation of renal microvascular matrix. Evidence suggests a potential protective role of active vitamin D on ischemic injury by downregulating MMPs. In the present study, we aimed to determine the expression and level of MMP-2 and MMP-9 in renal IRI model and the potential beneficial effect of paricalcitol on both level and expression of MMPs and tubular injury caused by IRI.

MATERIALS AND METHODS

20 Wistar albino rats were divided into three groups: sham-operated, ischemia-reperfusion, and paricalcitol-pretreated. IRI model was induced by bilateral clamping of renal arteries for 45 minutes followed by 24 hours of reperfusion. The analysis of serum creatinine and levels of MMPs were performed after 24 hours of IRI. The effects of paricalcitol on the quantity and expression of MMP-2 and MMP-9 in renal tubular epithelial cells were investigated by enzyme-linked immunosorbent assay and immunohistochemistry, respectively. The pathological examinations were performed to score tubular damage by light microscopy.

RESULTS

Creatinine levels decreased in the paricalcitol group, although this was not proven to be significant. Rats in the paricalcitol group showed significant decrease in both level and expression of MMPs and in tubular injury scores as compared to the IRI group.

CONCLUSION

Paricalcitol may attenuate renal tubular injury caused by IRI by decreasing both level and expression of MMPs. Further studies are required to investigate the interplay between activated vitamin D and MMPs in AKI.
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Alpha-lipoic acid alleviates colistin nephrotoxicity in rats

Colistin methanesulfonate (CMS), a clinical form of colistin, is widely used as a last-line treatment for multidrug-resistant (MDR) gram-negative bacterial infections in critically ill patients presenting a considerably high mortality rate. However, nephrotoxicity is considered to be a critical adverse effect that limits CMS's clinical use. Alpha-lipoic acid (ALA) is a strong antioxidant that is effective in preventing nephrotoxicity in many models. The aim of this study was to investigate ALA's ability to protect against nephrotoxicity induced by colistin in rats. Male Wistar albino rats were randomly divided into four groups. Group 1 was the control group (Control; n = 6), in which isotonic saline was administered to the rats. Group 2 was the ALA group (ALA; n = 6) in which rats received 100 mg/kg ALA. Groups 3 was the CMS (CMS; n = 7) in which 450.000 IU/kg/day of CMS was administered to the rats. Groups 4 was the CMS + ALA group (n = 6), in which rats were injected with 100 mg/kg of ALA 30 min before administration of CMS. All injections were performed intraperitoneally at 1, 4, 7, and 10 days. Urine was collected by using a metabolic cage for 24 h after each administration. The rats were euthanized under ether anesthesia after 24 h of the last administration. Blood and kidney samples then were collected for histological and biochemical analysis. ALA pretreatment could reverse the effects of colistin-induced nephrotoxicity, partly through its suppressing effect on Nox4 and caspase-3, which in turn results in its antioxidant and antiapoptotic effect. Therefore, ALA may be an effective strategy for the management of colistin nephrotoxicity.

Protective effects of alpha-lipoic acid on bleomycin-induced skin fibrosis through the repression of NADPH Oxidase 4 and TGF-β1/Smad3 signaling pathways

The aim of this study was to determine the protective effects of alpha-lipoic acid (ALA), which is known as a powerful antioxidant, and the possible related molecular mechanisms that mediate its favorable action on skin fibrosis in the bleomycin (BLM)-induced scleroderma (SSc) model in mice. The experimental design was established with four groups of eight mice: Control, ALA (100 mg/kg), BLM (5 μg/kg), and BLM + ALA group. BLM was administered via subcutaneous (sc) once a day while ALA was injected intraperitoneally (ip) twice a week for 21 days. Histopathological and biochemical analyses showed that ALA significantly reduced BLM-induced dermal thickness, inflammation score, and mRNA expression of tumor necrosis factor-alpha (TNF-α) in the skin. Besides, the mRNA expressions of the subunits of NADPH oxidase, which are Nox4 and p22phox, were found to be significantly induced in the BLM group. However, ALA significantly reduced their mRNA expression, which were in parallel to its decreasing effect on serum total oxidant status (TOS) level. Moreover, it was found that ALA downregulated the mRNA expressions of alpha-smooth muscle actin (α-SMA), collagen type I and fibronectin in the skin tissue of the BLM group. Additionally, it was shown that ALA reduced significantly the TGF-β1 and p-Smad3 protein expressions in the BLM + ALA group. On the other hand, ALA did not exhibit any significant effect on the p38 mitogen-activated kinase (MAPK) activation induced by BLM. All these findings point out that ALA may be a promising treatment for the attenuation of skin fibrosis in SSc patients.

Rapid Fibroblast Cell Culture Characterization with Impedimetric Label‐free Heat Shock Protein – 47 Biosensor

In this study, for the first time in literature, an impedimetric biosensor technology was developed to determine Heat Shock Protein‐47 (HSP‐47) for the characterization of primary skin fibroblast cells. Gold nanoparticle electrodes (GNPE) were modified with amino‐functionalized graphene oxide layers and anti‐HSP‐47 were immobilized on this layer. The performance of the biosensor was tested with real samples as cell lysates. The low detection limit (LOD) and the linear detection limit (LOQ) of the biosensor were calculated as 9.47 pg/mL and 3.23 pg/mL, respectively. Linear measurement range was obtained between 10–160 pg/mL HSP‐47. The reproducibility of the biosensor was good.

Paricalcitol pretreatment attenuates renal ischemia/reperfusion injury by inhibiting p38 MAPK and activating PI3K/Akt signaling pathways

Objective

This study aimed to investigate the renoprotective effects of paricalcitol, a synhetic vitamin D analog, through its possible roles on p38 MAPK and PI3K/Akt signaling pathways to prevent oxidative stress, inflammation and apoptosis during renal I/R.

Materials and methods

Total 20 kidney tissues of sham (n = 6), subjected to renal I/R bilaterally for 45 min ischemia followed by 24 h reperfusion (n = 7) and paricalcitol (0.3 μg/kg, ip) pretreated Wistar albino rats (n =7) were used in this study. Interstitial inflammation and active caspase-3 expression were evaluated histologically. TNF-α, IL-1β, kidney injury molecule-1 (KIM-1), MDA and SOD activity in kidneys were analysed biochemically. Furthermore, activation of p38 MAPK, PI3K/Akt signaling pathways and NFκB p65 were evaluated by western blot.

Results

Paricalcitol pretreatment significantly reduced interstitial inflammation during renal I/R, which was consistent with decreased tumor TNF-α, IL-1β, active caspase-3 and KIM-1 expression. Paricalcitol also reduced MDA level and attenuated the reduction of SOD activity in the kidney during I/R. Moreover, paricalcitol could suppress the p38 MAPK and NFκB p65, and also activate PI3K/Akt signaling pathway during renal I/R.

Conclusion

All these findings indicate that paricalcitol may be an effective practical strategy to prevent renal I/R injury.

Effects of epigallocatechin-3-gallate (EGCG) on a scleroderma model of fibrosis

Objective

The aim of the present study was to evaluate the potential protective effects of epigallocatechin-3-gallate (EGCG) on fibrosis in bleomycin induced scleroderma model.

Materials and methods

Thirty-two healthy female Balb-c mice with the average body weight of 22±5 g were used in this study. The mice were randomly divided into four groups as control (n=8), Bleomycin (n=8), Bleomycin+EGCG (n=8) and EGCG (n=8). Skin tissue samples were collected to quantify matrix metalloproteinases (MMP-1, MMP-8, MMP-13), p-SMAD 2/3 and SMAD 2/3 in protein homogenates by western blotting. TGF-β1 expression was determined by real-time PCR. Immunohistopathological and histopathological examinations of skin tissues were also done.

Results

When measured with Masson Trichrome, EGCG treatment was found to decrease fibrosis in connective tissue compared to the BLM injected control. EGCG was decreased dermal fibrosis. Bleomycin+EGCG group showed a significant reduction in fibrosis at the dermal surface area using hematoxylin measurements compared with the BLM group. MMP-1, MMP-8 protein levels were increased and p-SMAD 2/3 protein level was decreased. TGF-β mRNA expression was decreased in the EGCG+BLM group compared with the BLM group.

Conclusion

These results suggest an antifibrotic role for EGCG.

Antioxidant Effect of Epigallocatechin-3-Gallate in a Bleomycin-Induced Scleroderma Model

Objectives

This study aims to evaluate the antioxidant effects of epigallocatechin-3-gallate (EGCG) in a bleomycin (BLM)-induced scleroderma model.

Materials and methods

Thirty-two healthy female Balb-c mice (6-8-week-old; weighing 22±5 g) were used in this study. The mice were randomly divided into four groups: control (n=8), BLM (n=8), BLM+EGCG (n=8), and EGCG (n=8). Skin tissue specimens were collected at the end of the experiments. Histopathological examinations of skin tissues were performed. Skin samples were assessed for total superoxide dismutase activity and malondialdehyde content. The phosphorylation of p-38 mitogen-activated protein kinase and Akt protein (the serine-threonine protein kinase encoded by the AKT), as well as the nuclear factor-kappa B levels, were analyzed by western blotting.

Results

Epigallocatechin-3-gallate-treated groups were observed to have reduced connective tissue fibrosis in the dermis area using Masson’s trichrome staining method. Pp-38 and nuclear factor-kappa B were found to decrease significantly in the BLM + EGCG group compared with the BLM group. Parallel to these findings, phosphorylated Akt protein was found to increase in the BLM + EGCG group compared with the BLM group. Superoxide dismutase activity was increased in the EGCG group and content of malondialdehyde level was decreased in EGCG groups.

Conclusion

The results of the present study demonstrated that EGCG represses pp-38 and nuclear factor-kappa B signaling pathways, exerting a protective effect for scleroderma through its anti-oxidative role.

Alpha lipoic acid attenuates iron induced oxidative acute kidney injury in rats

Iron has been implicated in oxidative tissue injury owing to its ability to generate reactive oxygen species (ROS). We investigated the reno-protective effects of alpha lipoic acid (ALA) by investigating its effects on the kidney isoform of NADPH oxidase (Nox4) and the specific signaling pathways, p38 MAPK and PI3K/Akt, which participate in apoptosis and survival, respectively. We established four groups of seven rats: control, 100 mg/kg ALA, 80 mg/kg iron sucrose (IS) and IS + ALA. IS and ALA were injected intravenously and rats were sacrificied after 6 h. The mRNA expression of the subunits of NADPH oxidase, Nox4 and p22phox; tumor necrosis factor-alpha (TNF-α); and kidney injury molecule-1 (KIM-1) were measured using quantitative real time polymerase chain reaction (qRT-PCR). Active caspase-3 protein expression was evaluated by immunostaining. Also, p38 MAPK and PI3K/Akt signaling pathways were analyzed using western blot. ALA suppressed the mRNA expression of Nox4, p22phox, TNF-α and KIM-1. Active caspase-3 protein expression induced by IS was decreased by ALA. ALA also suppressed p38 MAPK and activated the PI3K/Akt signaling pathway following IS administration. We found that ALA may be an effective strategy for preventing oxidative acute kidney injury caused by IS.

Role of p38 MAPK, Akt and NFκB in renoprotective effects of nebivolol on renal ischemia-reperfusion injury in rats

Renal ischemia-reperfusion (I-R) injury is a complex pathophysiologic condition characterized by oxidative stress, inflammation and apoptosis. We investigated the potential renoprotective effect of nebivolol, a β1 adrenergic receptor blocker, against renal I-R injury. We focused on the role of nebivolol in activating p38 mitogen-activated protein kinase (MAPK) signaling, Akt (protein kinase B) and nuclear factor-κB (NFκB) transcription factors, which contribute to oxidative stress, inflammation and apoptosis during renal I-R. We divided 20 adult male Wistar albino rats into three experimental groups. Group 1 was a sham control in which only laparotomy was performed. Group 2 was the I-R group in which both kidneys were made ischemic for 45 min, then reperfused for 24 h. Group 3 was the I-R + nebivolol group in which 10 mg/kg nebivolol was administrated by gavage for 7 days before I-R. We measured Inflammation, oxidative stress and active caspase-3 as well as activation of p38 MAPK, Akt (protein kinase B) and NFκB transcription factor. Nebivolol significantly reduced oxidative stress and increased superoxide dismutase levels during renal I-R. We found that nebivolol significantly decreased interstitial inflammation, and TNF-α and interleukin-1β mRNA expression. Nebivolol significantly reduced active caspase-3 and kidney injury molecule-1 (KIM-1) expressions. Nebivolol also significantly decreased activation of p38 MAPK signaling and NFκB, and induced Akt activation during renal I-R. Our findings suggest that nebivolol may be useful for management of renal I-R injury.

Relationship of Wnt pathway activity and organ involvement in scleroderma types

OBJECTIVE

Scleroderma (SSc) is a chronic inflammatory autoimmune disease characterized by fibrosis in the skin and internal organs. In SSc, the heart, lung, kidney, gastrointestinal (GIS) system, muscle, and peri-articular structures are damaged. There is no study of the relationship between SSc type, stage, pathogenesis, organ involvement, and Wnt signaling. In this study, we aimed to show the relationship of the Wnt gene family and antagonists in SSc subtypes and different organ involvement.

METHODS

Eighty-five SSc patients and 77 controls were included in this study. The gene expressions and protein levels of the Wnt family and antagonists were analyzed from blood samples. The relationship between these parameters and disease stage, type, and organ involvement were evaluated.

RESULTS

Wnt-1, Wnt-10b, Wnt-2, and Wnt-6 gene expressions are increased and Axin-2, DKK-1, and Kremen protein expressions are decreased in SSc. Wnt-3a and Wnt-10a gene expressions are increased in generalized SSc compared to limited SSc. Wnt-1, Wnt-2 gene expressions are increased significantly in pulmonary arterial hypertension (PAH)(+) SSc compared to PAH(-) SSc. There was a positive correlation between the modified Rodnan skin score and Wnt-2 in SSc. There was a significant positive correlation between GIS involvement score and Wnt-1, Wnt-2, Wnt-4, Wnt-8a, Wnt-9b in SSc.

CONCLUSION

Wnt-1 and Wnt-2 were found higher in scleroderma and organ involvement. They may play a role in the pathogenesis of the disease.

Evaluation of the first Turkish in vitro diagnostic symposium

In vitro diagnostic (IVD) medical laboratory devices, tests and equipment are closely related with public health, patient safety and the safety of all who utilize these tools in laboratories. The close monitoring of the process from the production line to the end-point user is crucial so that IVD devices and tests do not pose a risk to individuals and society. Based on this background, the “First Turkish in vitro Diagnostic Symposium: Medical Laboratory Tests” was held in February, 2016. The symposium was organized by the cooperation of Turkish Biochemical Society, Izmir Branch and Dokuz Eylul University Health Sciences Institute along with the contributions of TurkLab Calibration Association. It was intended that the meeting would shed light on questions such as, ‘What is the place and importance of IVD in Turkey?’, ‘What are the responsibilities of educational institutions?’, ‘What is the role of Ministry of Health?’, with the aim that the answers would help to determine the infrastructure needed for successful production of IVD medical devices in Turkey. At the end of the symposium, feedback from participants were collected via a questionnaire. This article presents the general evaluation of the symposium based on the results of this survey.

Evaluation of potential tumor markers that may predict neoadjuvant treatment efficiency in rectal cancer

Objectives

The recurrence of rectal cancer or its resistance to neoadjuvant treatment develops due to the adaptation to hypoxia, apoptosis or autophagy. Survivin, one of the inhibitors of apoptosis; Beclin 1, which is a positive regulator in the autophagy pathway; and hypoxia-inducible factor-1α (HIF-1α) and carbonic anhydrase-9 (CA9), which are associated with tumor tissue hypoxia, may be related to resistance to treatment. Our aim was to evaluate the potential tumor markers that may help to monitor the response to neoadjuvant treatment in locally advanced rectal cancer (RC).

Methods

Twenty-five patients with locally advanced RC were included in the study. Gene expression and protein levels of Beclin 1, Survivin, HIF-1α, and CA9 were analyzed in fresh tissue specimens and blood samples. The relationships of these markers to tumor staging and regression grade were evaluated.

Results

Higher blood CA9 gene expression levels and lower blood HIF-1α protein levels were found in the response group according to tumor regression grade. After neoadjuvant treatment, tissue Beclin 1 and blood Survivin gene expressions and tissue CA9, blood Beclin 1 and blood HIF-1α protein levels decreased significantly.

Conclusion

Beclin 1, Survivin, HIF-1α ve CA9 may help to predict the effects of the applied treatment approach.

Porcupine inhibitors LGK-974 and ETC-159 inhibit Wnt/β-catenin signaling and result in inhibition of the fibrosis

OBJECTIVES

We evaluated potential therapeutic efficacy of LGK-974 and ETC-159 in fibrotic scleroderma cells.

METHODS

Primary scleroderma dermal fibroblast cells of mouse origin (SSc fibroblasts) and primary fibrotic lung fibroblast cells of human origin (CCL-191) were used in this study. PORCN inhibitors LGK-974 (S7143, 1 μM; Selleckchem, USA) and ETC-159 (S7143, 10 μM; Selleckchem, USA) were used. The possible therapeutic effects of LGK-974 and ETC-159 on scleroderma cells and fibrosis cells were examined. Cell viability experiments were performed for each substance, and the expression levels of WNT and fibrosis marker genes were determined by qPCR. Western blotting was also used to determine collagen, fibronectin and α-SMA protein markers.

RESULTS

This study showed that LGK-974 and ETC-159 probable protein-cysteine N-palmitoyltransferase porcupine (PORCN) inhibitors exert potent antifibrotic effects and reduce fibrosis by modulating the TGF-β signaling pathway in scleroderma cells. Using LGK-974 and ETC-159 PORCN inhibitors, either alone or in combination, can affect collagen deposition and fibrosis in patients with SSc.

CONCLUSIONS

LGK-974 and ETC-159 may be a possible long-term therapeutic target for scleroderma.

A preliminary study of possible fibrotic role of meprin metalloproteases in scleroderma patients

OBJECTIVES

This study aims to investigate the possible fibrotic role of meprin metalloproteases and possible fibrotic effects of activator protein-1 (AP-1) in scleroderma patients.

PATIENTS AND METHODS

Between April 2018 and April 2019, a total of 85 scleroderma patients (9 males, 76 females; mean age: 54.9 years; range, 22 to 80 years) who met the 2013 American College of Rheumatology/European League Against Rheumatism criteria and 80 healthy control individuals (10 males, 70 females; mean age 42.9 years; range, 19 to 65 years) were included. Patients' data and blood samples were collected. Messenger ribonucleic acid expressions of interleukin (IL)-6, AP-1 subunits, and tumor necrosis factor-alpha (TNF-α) were analyzed by quantitative real-time polymerase chain reaction. Serum meprin alpha and beta protein levels were analyzed using the enzyme-linked immunosorbent assay.

RESULTS

Meprin alpha and meprin beta protein levels increased in scleroderma patients. The AP-1 subunits (c-Fos, c-Jun), IL-6, and TNF-α increased in scleroderma patients, compared to controls.

CONCLUSION

Our results provide evidence showing that increased meprins levels may be related to AP-1 levels and increased meprins levels may responsible for increased inflammatory TNF-α and IL-6 levels. All these data suggest meprins as promising therapeutic targets to restore the balance between inflammation and extracellular matrix deposition in scleroderma.

Effects of upadacitinib and PD29 on oxidative damage and inflammation in bleomycin-induced scleroderma model kidney tissues

Objective: Scleroderma (SSc) is a rare autoimmune tissue disease. There is currently no effective treatment for SSc. The aim of this study was to investigate the antioxidant and anti-inflammatory effects of upadacitinib and PD29 on total oxidant status (TOS), total antioxidant status (TAS), malondialdehyde (MDA), catalase (CAT), glutathione (GSH) peroxidase levels, and interleukin-6 (IL-6) and interleukin-13 ( IL-13) in kidney tissues of an experimental SSc model. Materials and Methods: The experimental design was established with five groups of eight mice: Control, bleomycin (BLM) (5 μg/kg), BLM + upadacitinib (3mg/kg), BLM + PD29 (5 mg/kg) and BLM + PD29 + upadacitinib group. BLM was administered subcutaneously once a day for 21 days. PD29 was administered subcutaneously and upadacitinib (gavage) were injected for 21 days. Renal tissues were collected at the end of the experiment. Renal TOS, TAS, MDA, CAT, GSH levels, and IL-6 and IL-13 gene expressions were evaluated. Results: Upadacitinib and PD29 affected oxidant status and TOS. MDA levels decreased, and GSH, CAT, and TAS levels increased. Also, upadacitinib and PD29 decreased inflammation via IL-6 and IL-13 cytokines. Conclusion: Upadacitinib and PD29 may have therapeutic roles for SSc renal crisis.