Glomerular nephrotoxicity of aminoglycosides

In Vitro Activity of Allium cepa Organosulfur Derivatives against Canine Multidrug-Resistant Strains of Staphylococcus spp. and Enterobacteriaceae

BACKGROUND

The increase of multi-resistant bacteria, especially Staphylococcus spp. and Enterobacteriaceae, constitutes a challenge in veterinary medicine. The rapid growth of resistance is outpacing antibiotic discovery. Innovative strategies are needed, including the use of natural products like Allium species (Allium sativum L. and Allium cepa L.), which have been used empirically for centuries to treat infectious diseases in humans and farm and aquaculture animals due to their antibacterial properties.

METHODS

This study aimed to evaluate the in vitro activity of two Allium-derived compounds, propyl propane thiosulfinate (PTS) and propyl propane thiosulfonate (PTSO), against multi-resistant Staphylococcus spp. (n = 30) and Enterobacteriaceae (n = 26) isolated from dogs referred to a veterinary teaching hospital in Madrid.

RESULTS AND DISCUSSION

The results indicated the in vitro efficacy of PTSO/PTS against the tested bacterial strains, and 56.7% of Staphylococcus pseudintermedius and 53.8% of Enterobacteriaceae showed sensitivity to PTS and PTSO compared with classic antibiotics. In addition, 50% of S. pseudintermedius strains resistant to erythromycin, ibofloxacin, difloxacin and orbifloxacin and 50% of Enterobacteriaceae strains resistant to tetracycline and doxycycline were sensitive to PTS and PTSO. Although studies are needed to verify their efficacy in vivo, the combined use of PTS and PTSO exhibits promise in enhancing bacterial sensitivity against S. pseudintermedius and Enterobacteriaceae infections, providing a first insight into the potential of both compounds in veterinary practice.

Aminoglycoside uptake, stress, and potentiation in Gram-negative bacteria: new therapies with old molecules

SUMMARYAminoglycosides (AGs) are long-known molecules successfully used against Gram-negative pathogens. While their use declined with the discovery of new antibiotics, they are now classified as critically important molecules because of their effectiveness against multidrug-resistant bacteria. While they can efficiently cross the Gram-negative envelope, the mechanism of AG entry is still incompletely understood, although this comprehension is essential for the development of new therapies in the face of the alarming increase in antibiotic resistance. Increasing antibiotic uptake in bacteria is one strategy to enhance effective treatments. This review aims, first, to consolidate old and recent knowledge about AG uptake; second, to explore the connection between AG-dependent bacterial stress and drug uptake; and finally, to present new strategies of potentiation of AG uptake for more efficient antibiotic therapies. In particular, we emphasize on the connection between sugar transport and AG potentiation.

Overview of Antibiotic-Induced Nephrotoxicity

Drug-induced nephrotoxicity accounts for up to 60% of cases of acute kidney injury (AKI) in hospitalized patients and is associated with increased morbidity and mortality in both adults and children. Antibiotics are one of the most common causes of drug-induced nephrotoxicity. Mechanisms of antibiotic-induced nephrotoxicity include glomerular injury, tubular injury or dysfunction, distal tubular obstruction from casts, and acute interstitial nephritis (AIN) mediated by a type IV (delayed-type) hypersensitivity response. Clinical manifestations of antibiotic-induced nephrotoxicity include acute tubular necrosis (ATN), AIN, and Fanconi syndrome. Given the potential nephrotoxic effects of antibiotics on critically ill patients, the use of novel biomarkers can provide information to optimize dosing and duration of treatment and can help prevent nephrotoxicity when traditional markers, such as creatinine, are unreliable. Use of novel kidney specific biomarkers, such as cystatin C and urinary kidney injury molecule-1 (KIM-1), may result in earlier detection of AKI, dose adjustment, or discontinuation of antibiotic and development of nonnephrotoxic antibiotics.

Further insights into the impact of rebamipide on gentamicin-induced nephrotoxicity in rats: modulation of SIRT1 and β-catenin/cyclin D1 pathways

Gentamicin (GM) is an effective antibiotic administered to treat acute Gram-negative infections. Nevertheless, its clinical application is limited due to nephrotoxicity. Therefore, our research aimed to investigate the potential renoprotective impact of rebamipide (RBM), a gastroprotective drug, on GM-induced kidney damage in rats, as well as putative nephroprotective pathways. RBM was orally administered (100 mg/kg/d for 14 d) commencing 7 d before the administration of GM (100 mg/kg/d, intraperitoneally). Nephrotoxicity was elucidated, and the silent information regulator 1 (SIRT1) and β-catenin/cyclin D1 pathways were assessed. GM induced a significant elevation in the serum levels of creatinine, blood urea nitrogen (BUN), and kidney injury molecule-1 (KIM-1), as well as the relative kidney index. In addition, GM increased lipid peroxidation and lowered total antioxidant capacity (TAC) level and superoxide dismutase (SOD) activity. GM administration also demonstrated a significant amplification in tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), nuclear factor-κappa B p65 (NF-κB p65), p38 mitogen-activated protein kinase (p38 MAPK), and caspase-3 kidney levels, as well as B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax)/Bcl-2 ratio. Notably, RBM treatment amended all these changes induced by GM. Furthermore, the potential role of SIRT1 and β-catenin-dependent signaling pathways in GM-induced renal injury was assessed. Our findings showed that GM-treated rats demonstrated a substantial decrease in SIRT1, nuclear factor E2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) along with an increase in β-catenin, forkhead box O-3a (FOXO-3a), and cyclin D1 protein expressions. RMB treatment markedly attenuated the deterioration caused by GM on these pathways. Additionally, RBM alleviated the GM-induced deleterious kidney tissue histopathology. In conclusion, our findings have verified that RBM can halt GM-induced renal injury by partly modulating SIRT1 and β-catenin pathways.

Urinary exosomes: a promising biomarker of drug-induced nephrotoxicity

Drug-induced nephrotoxicity (DIN) is a big concern for clinical medication, but the clinical use of certain nephrotoxic drugs is still inevitable. Current testing methods make it hard to detect early renal injury accurately. In addition to understanding the pathogenesis and risk factors of drug-induced nephrotoxicity, it is crucial to identify specific renal injury biomarkers for early detection of DIN. Urine is an ideal sample source for biomarkers related to kidney disease, and urinary exosomes have great potential as biomarkers for predicting DIN, which has attracted the attention of many scholars. In the present paper, we will first introduce the mechanism of DIN and the biogenesis of urinary exosomes. Finally, we will discuss the changes in urinary exosomes in DIN and compare them with other predictive indicators to enrich and boost the development of biomarkers of DIN.

Exploring porcine kidney explants as a model for the study of nephrotoxins and the therapeutic potential of phytic acid

The use of in vivo models to assess nephrotoxicity has faced ethical limitations. A viable alternative is the ex vivo model that combines the 3 R principles with the preservation of tissue histology. Here, we established a gentamicin nephrotoxicity model using pigs` kidney explants and investigated the effect of phytic acid (IP6) against gentamicin- induced nephrotoxicity. A total of 360 kidney explants were divided into control, gentamicin (10 mM), IP6 (5 mM), and gentamicin+IP6 groups. The activity of gammaglutamyltransferase (GGT), creatinine levels, histological assessment, oxidative stress, and inflammatory cytokine expression were analyzed. Exposure to gentamicin induced an increase in GGT activity, creatinine levels, lesion score, lipoperoxidation and IL-8 expression. Explants exposed to IP6 remained like the control. The addition of IP6 to gentamicin prevented tissue damage, increasing the antioxidant status and gene expression of IL-10. This model proved to be an adequate experimental approach for identifying nephrotoxins and potential products to modulate the toxicity.

Off target toxicities and links with physicochemical properties of medicinal products, including antibiotics, oligonucleotides, lipid nanoparticles (with cationic and/or anionic charges). Data review suggests an emerging pattern

Toxicology is an essential part of any drug development plan. Circumnavigating the risk of failure because of a toxicity issue can be a challenge, and failure in late development is extremely costly. To identify potential risks, it requires more than just understanding the biological target. The toxicologist needs to consider a compound's structure, it's physicochemical properties (including the impact of the overall formulation), as well as the biological target (e.g., receptor interactions). Understanding the impact of the physicochemical properties can be used to predict potential toxicities in advance by incorporating key endpoints in early screening strategies and/or used to compare toxicity profiles across lead candidates. This review discussed the risks of off-target and/or non-specific toxicities that may be associated with the physicochemical properties of compounds, especially those carrying dominant positive or negative charges, including amphiphilic small molecules, peptides, oligonucleotides and lipids/liposomes/lipid nanoparticles. The latter of which are being seen more and more in drug development, including the recent Covid pandemic, where mRNA and lipid nanoparticle technology is playing more of a role in vaccine development. The translation between non-clinical and clinical data is also considered, questioning how a physicochemical driven toxicity may be more universal across species, which means that such toxicity may be reassuringly translatable between species and as such, this information may also be considered as a support to the 3 R's, particularly in the early screening stages of a drug development plan.

Understanding the role of chronopharmacology for drug optimization: what do we know?

INTRODUCTION

Circadian rhythm influences the pharmacokinetics and pharmacodynamics of a number of drugs and affects their therapeutic efficacy and toxicity depending on the time of day they are administered. Chronopharmacology is a method for incorporating knowledge about circadian rhythm into pharmacotherapy. Chronotherapy, which is the clinical application of chronopharmacology, is particularly relevant when the risk and/or severity of symptoms of a disease change in a predictable manner over time. Chronotherapy has potential benefits in the treatment of many diseases.

AREAS COVERED

Although a considerable amount of knowledge about chronopharmacology and chronotherapy has been accumulated, its therapeutic application in clinical practice remains limited in terms of therapy optimization. Resolution of these issues will improve our ability to deliver adequate drug treatment.

EXPERT OPINION

We propose four approaches for promoting chronotherapy-based drug treatment in clinical practice: targeting drug development and regulatory authorities; education about chronotherapy; drug information for both health professionals and consumers; and a chronotherapy network.

Protective Effect of Neutral Electrolyzed Saline on Gentamicin-Induced Nephrotoxicity: Evaluation of Histopathologic Parameters in a Murine Model

Background and Objectives: Gentamicin (GM) is a nephrotoxic aminoglycoside. Neutral electrolyzed saline (SES) is a compound with anti-inflammatory, antioxidant, and immunomodulatory properties. The objective of the present study was to evaluate whether kidney damage by GM can be prevented and/or reversed through the administration of SES. Materials and Methods: The study was carried out as a prospective, single-blind, five-arm, parallel-group, randomized, preclinical trial. The nephrotoxicity model was established in male BALB/c mice by administering GM at a dose of 100 mg/kg/day intraperitoneally for 30 days, concomitantly administering (+) SES or placebo (physiologic saline solution), and then administering SES for another 30 days after the initial 30 days of GM plus SES or placebo. At the end of the test, the mice were euthanized, and renal tissues were evaluated histopathologically. Results: The GM + placebo group showed significant tubular injury, interstitial fibrosis, and increased interstitial infiltrate of inflammatory cells compared with the group without GM. Tubular injury and interstitial fibrosis were lower in the groups that received concomitant GM + SES compared with the GM + placebo group. SES administration for 30 days after the GM administration periods (GM + placebo and GM + SES for 30 days) did not reduce nephrotoxicity. Conclusions: Intraperitoneal administration of SES prevents gentamicin-induced histologic nephrotoxicity when administered concomitantly, but it cannot reverse the damage when administered later.

Aminoglycosides use has a risk of acute kidney injury in patients without prior chronic kidney disease

The outcome of acute kidney injury (AKI) as a result of aminoglycosides (AGs) use remains uncertain in patients without prior chronic kidney disease (CKD). Therefore, we explored the outcomes of AGs use on AKI episodes associated with renal recovery and progress in patients without prior CKD in Taiwan. This was a retrospective cohort study by using the Taipei Medical University Research Database from January 2008 to December 2019. 43,259 individuals without CKD who had received parenteral AGs were enrolled. The exposed and unexposed groups underwent propensity score matching for age, gender, patients in intensive care unit/emergency admission, and covariates, except serum hemoglobin and albumin levels. We identified an exposed group of 40,547 patients who used AGs (median age, 54.4 years; 44.3% male) and an unexposed group of 40,547 patients without AG use (median age, 55.7 years; 45.5% male). There was the risk for AKI stage 1 (adjusted hazard ratio [HR] 1.34; 95% confidence interval [CI] 1.00-1.79; p = 0.05) in patients that used AGs in comparison with the control subjects. Moreover, patients using AGs were significantly associated neither with the progression to acute kidney disease (AKD) stages nor with the progression to end-stage renal disease (ESRD) on dialysis. Further analyzed, there was an increased risk of AKI episodes for serum albumin levels less than 3.0 g/dL and hemoglobin levels less than 11.6 g/dL. Among patients without prior CKD, AGs-used individuals were associated with AKI risks, especially those at relatively low albumin (< 3.0 g/dL) or low hemoglobin (< 11.6 g/dL). That could raise awareness of AGs prescription in those patients in clinical practice.

Campylobacter jejuni subdural hygroma infection in a 2-year old boy: case report and a brief literature review

Background

Campylobacter jejuni is a common cause of acute gastroenteritis, but central nervous system infections are rare manifestations of Campylobacter infection. Therefore, C. jejuni trauma-related subdural hygroma infection in children is poorly described in the literature.

Case presentation

We described a 2-year old boy with lobar holoprosencephaly presenting with subdural hygroma following head trauma. C. jejuni infection was confirmed from a subdural hygroma sample by culture as well as by DNA sequencing of a broad range 16S rDNA PCR product. Cerebrospinal fluid from the ventriculoperitoneal shunt remained sterile. Combined neurosurgical and antimicrobial treatment led to complete recovery. Review of the literature showed that the most common manifestation of Campylobacter central nervous system infection is meningitis, mostly in neonates, and subdural hygroma infection was described for only one case.

Conclusions

Subdural hygroma infection caused by C. jejuni is a rare clinical condition in children. Molecular methods represent an important tool for the detection of rare or unexpected pathogens. No standard recommendations for antimicrobial treatment of C. jejuni subdural space infection in children are available, but meropenem treatment combined with surgery seems to be an effective approach.

Protective effect of empagliflozin on gentamicin-induced acute renal injury via regulation of SIRT1/NF-κB signaling pathway

Gentamicin is a highly effective antibiotic. However, its major complication is nephrotoxicity. This study investigated the beneficial effects of empagliflozin against gentamicin-induced nephropathy. Kidney damage was induced in male Wistar rats by administration of gentamicin (100 mg/kg/day, i.p.) for 8 days. Two doses of empagliflozin (10 and 20 mg/kg, p.o.) were concomitantly given with gentamicin for 8 days. Gentamicin administration increased serum creatinine, urea, and cystatin C concentrations. Empagliflozin in both doses ameliorated these changes via mitigation of gentamicin-induced increase in renal oxidative stress, inflammation, and apoptosis. Empagliflozin added to GM treatment led to lower measured levels of TGF-B, NF-κB and caspase 3, and only the higher dose increased PAX2 levels indicating an improvement in tubular regeneration. Additionally, empagliflozin (20 mg/kg/day) markedly prevented gentamicin-induced histopathological changes. The protective effects of empagliflozin may be mediated by decreasing gentamicin concentration in renal tissue and possibly other effects like antioxidant and antiapoptotic effects.

Reported Cases of Urinary Tract Infections and the Susceptibility of Uropathogens from Hospitals in Northern Ghana

As global studies report varying trends in antibiotic susceptibility of uropathogens, it is necessary to have current and constant information on the prevalence of urinary tract infections, the causative pathogens, and their susceptibility profiles, for effective management in specific geographical settings. This prospective cross-sectional study focused on the prevalence of urinary tract infections, etiological agents, and their antibiogram in a secondary and tertiary care hospital in Northern Ghana. Urine samples collected from 219 patients of all age groups were cultured on cysteine lactose electrolyte deficient agar. Pathogens were identified following standard microbiological methods, and their susceptibility to antibiotics was determined by the Kirby-Bauer disk diffusion method. Approximately 34% of the patients had significant bacteria, but the prevalence was slightly higher (P = .763) in the Tertiary care hospital (37.3%) than in the Secondary hospital (30.3%). Patients who were 60 years and above (27.0%) were commonly found with UTIs followed by the year group 20 to 29 years (20.3%). Although all the diagnoses had a positive relationship with urinary tract infection except Pyelonephritis, none of the underlying conditions was a significant (P > .05) predictor of urinary tract infection, with the odds ratio indicating that patients with hyperparathyroidism and dysuria had 2.606 times more likely increased risk or predictor of urinary tract infection. Ten different pathogens were identified, but Escherichia coli and Staphylococcus saprophyticus were frequently encountered. Gram-negative isolates generally showed more resistance. High resistance against ampicillin (100%), trimethoprim-sulfamethoxazole (88.5%), chloramphenicol (84.6%), augmentin (69.2%), ceftriaxone (69.2%), and ciprofloxacin (61.5%) were recorded. Amikacin was relatively effective against isolated pathogens. The high records of resistance among uropathogens and the occurrence of multidrug resistance (92%) reiterate the urgent call for rigorous surveillance of antimicrobial resistance among infectious pathogens in Ghana.

Glutamine alleviates the renal dysfunction associated with gentamicin-induced acute kidney injury in Sprague-Dawley rats

Sepsis is a clinical condition caused by an uncontrolled response to an infection, leading to acute kidney injury (AKI) and an increased risk of mortality. Although life support and antibiotic therapy are available, the mortality rate remains high in patients with sepsis. The present study investigated the therapeutic effect of glutamine on gentamicin-induced acute kidney injury in Sprague-Dawley rats. We randomly grouped 24 male rats to the normal control, AKI (control), glutamine 50 mg/kg, and glutamine 500 mg/kg groups. The dose was administered orally for 14 consecutive days. Rats treated with glutamine 500 mg/kg showed changes in systolic blood pressure. Glutamine increased renal blood flow, creatinine clearance, and the levels of potassium, creatinine, blood urea nitrogen, and urine osmolality, while reducing the relative excretion of sodium, potassium, urinary sodium, and plasma blood urea nitrogen and creatinine levels. In our study, glutamine supplementation reduced gentamicin-induced oxidative stress and increased catalase, superoxide dismutase, glutathione peroxidase, and glutathione levels in AKI rats. In addition, glutamine supplementation attenuated the severity of pathological features in this model. Collectively, our results showed that gentamicin has therapeutic potential against gentamicin-induced AKI due to its ability to mitigate the effects of oxidative stress.

The concurrent therapeutic potential of adipose-derived mesenchymal stem cells on Gentamycin-induced hepatorenal toxicity in rats

BACKGROUND

Adipose mesenchymal stem cells (AMSCs) are a type of stem cell employed to repair damaged organs. This study aimed to see how effective AMSCs are at treating gentamycin-induced hepatorenal damage in rats.

METHODS

18 male Wister rats were assigned into three groups; control, Gentamycin (GM), and GM+AMSCs. GM induced hepatorenal toxicity through daily injection (100 mg/kg, i.p.) for eight days. On day 9, AMSC (106 cells/ml/rat) was injected intravenously.

RESULTS

Creatinine, urea, uric acid, AST, ALP, ALT, TNF-, and MDA levels decreased, whereas IL-10, GSH, and CAT levels increased, indicating the therapeutic potency of intravenous injection AMSCs.

CONCLUSION

The current study demonstrated the simultaneous therapeutic efficacy of adipose mesenchymal stem cells on the liver and kidney in the treatment of Gentamycin-induced hepatotoxicity. These data show that AMSCs could be a feasible therapy option for liver and kidney disease.

Involvement of oxidative stress and toll-like receptor-4 signaling pathways in gentamicin-induced nephrotoxicity in male Sprague Dawley rats

Gentamicin (GM) is an antibiotic belonging to an aminoglycoside family that might induce nephrotoxicity in human and animal models via oxidative stress. Toll-like receptors (TLRs) are part of innate immune systems that participate in inflammatory responses. In this regard, we investigated the effect of GM on kidney functional and structural parameters, enzymatic antioxidant levels, and mRNA expression of TLR4 and IL6 in the rat kidney. Adult male Sprague Dawley rats were randomly divided into two groups (n = 10): Control and Gentamicin (100 mg/kg, i.p.). After ten days of GM administration, a blood sample was taken, and the kidneys were removed. The serum levels of creatinine (Cr) and blood urea nitrogen (BUN) were measured. Furthermore, the right kidney was preserved in formalin 10% for hematoxylin and eosin (H&E) staining, and the left kidney was kept at -80 °C for molecular and oxidative indexes analysis. Administration of GM caused tubular damages and functional disturbance. So that, Cr and BUN values in the GM group were higher than Control group. Furthermore, molecular findings showed upregulation of TLR4 and IL-6 mRNA expression in renal tissue of the GM-received group. In this study, superoxide dismutase (SOD) activity was slightly increased as a compensatory mechanism in response to elevated malondialdehyde (MDA) levels in the GM-treated group. On the other hand, the activity of catalase (CAT) and glutathione peroxidase (GPx) were significantly declined. Our results demonstrated that oxidative stress and subsequent TLR4 upregulation signaling pathways are involved in GM-induced nephrotoxicity.

Ameliorative impacts of Glycyrrhiza glabra root extract against nephrotoxicity induced by gentamicin in mice

Gentamicin is an effective antibiotic that has been used worldwide for many years. While considered an essential medicine by the WHO, gentamicin can also lead to severe kidney damage. This study explored the ameliorative effects of Glycyrrhiza glabra root extract on gentamicin-induced renal injury in mice. Four groups of n = 7 mice were used: (a) control; (b) G. glabra-only; (c) gentamicin-only; and (d) gentamicin plus G. glabra. Kidney samples were tested for: antioxidant enzyme activity (superoxide dismutase [SOD] and glutathione peroxidase [Gpx]); expression of HO-1 and nuclear factor erythroid 2-related factor 2 genes; expression of Cox-2 and Bax; cytokine levels (IL-1β, and IL-6); histopathological anomalies; and standard renal functional component levels (creatinine, urea, and blood urea nitrogen). The effects of gentamicin were generally reversed or normalized following treatment with G. glabra root extract. Gentamicin decreased Gpx and SOD parameters and increased IL-1 β and IL-6 levels, but these returned to normal in the G. glabra-treated group. Gentamicin upregulated tissue levels of Cox-2 and Bax, and downregulated HO-1 and Nrf-2 expression but again, and these levels returned to normal in the group treated with G. glabra. Mice that had received gentamicin exhibited acute renal blood vessel congestion, focal interstitial round cell aggregation, and hydropic degeneration of renal tubular epithelium. However, those that had also received G. glabra showed a normal histopathology. Findings from this study indicate that in mouse models, gentamicin-induced kidney damage can be reversed or ameliorated by administering G. glabra, so it can be considered as an effective complimentary therapy.

ACE2 activator diminazene aceturate exerts renoprotective effects in gentamicin-induced acute renal injury in rats

Acute Kidney Injury (AKI) comprises a rapidly developed renal failure and is associated with high mortality rates. The Renin-Angiotensin System (RAS) plays a pivotal role in AKI, as the over-active RAS axis exerts major deleterious effects in disease progression. In this sense, the conversion of Angiotensin II (Ang II) into Angiotensin-(1-7) (Ang-(1-7)) by the Angiotensin-converting enzyme 2 (ACE2) is of utmost importance to prevent worse clinical outcomes. Previous studies reported the beneficial effects of oral diminazene aceturate (DIZE) administration, an ACE2 activator, in renal diseases models. In the present study, we aimed to evaluate the therapeutic effects of DIZE administration in experimental AKI induced by gentamicin (GM) in rats. Our findings showed that treatment with DIZE improved renal function and tissue damage by increasing Ang-(1-7) and ACE2 activity, and reducing TNF-α. These results corroborate with a raising potential of ACE2 activation as a strategy for treating AKI.

HIF2alpha-Associated Pseudohypoxia Promotes Radioresistance in Pheochromocytoma: Insights from 3D Models

Pheochromocytomas and paragangliomas (PCCs/PGLs) are rare neuroendocrine tumors arising from chromaffin tissue located in the adrenal or ganglia of the sympathetic or parasympathetic nervous system. The treatment of non-resectable or metastatic PCCs/PGLs is still limited to palliative measures, including somatostatin type 2 receptor radionuclide therapy with [¹⁷⁷Lu]Lu-DOTA-TATE as one of the most effective approaches to date. Nevertheless, the metabolic and molecular determinants of radiation response in PCCs/PGLs have not yet been characterized. This study investigates the effects of hypoxia-inducible factor 2 alpha (HIF2α) on the susceptibility of PCCs/PGLs to radiation treatments using spheroids grown from genetically engineered mouse pheochromocytoma (MPC) cells. The expression of Hif2α was associated with the significantly increased resistance of MPC spheroids to external X-ray irradiation and exposure to beta particle-emitting [¹⁷⁷Lu]LuCl₃ compared to Hif2α-deficient controls. Exposure to [¹⁷⁷Lu]LuCl₃ provided an increased long-term control of MPC spheroids compared to single-dose external X-ray irradiation. This study provides the first experimental evidence that HIF2α-associated pseudohypoxia contributes to a radioresistant phenotype of PCCs/PGLs. Furthermore, the external irradiation and [¹⁷⁷Lu]LuCl₃ exposure of MPC spheroids provide surrogate models for radiation treatments to further investigate the metabolic and molecular determinants of radiation responses in PCCs/PGLs and evaluate the effects of neo-adjuvant-in particular, radiosensitizing-treatments in combination with targeted radionuclide therapies.

D-Limonene Alleviates Acute Kidney Injury Following Gentamicin Administration in Rats: Role of NF-κB Pathway, Mitochondrial Apoptosis, Oxidative Stress, and PCNA

Clinical application of gentamicin (GM) is well known to be associated with the development of acute kidney injury (AKI). This study was the first to investigate the possible protective effects of D-limonene (D-lim) on AKI following GM administration in rats. 32 rats arranged in four groups (n = 8): (1) the control group received saline intraperitoneally (0.5 ml/day) and orally (0.5 ml/day), (2) the D-lim group received D-lim (100 mg/kg) orally and saline (0.5 ml/day) intraperitoneally, (3) the GM group received GM (100 mg/kg/day) intraperitoneally and saline (0.5 ml/day) orally, and (4) the treated group received intraperitoneal GM (100 mg/kg) and oral D-lim (100 mg/kg). All treatments were performed daily for 12 consecutive days. Results revealed that D-lim ameliorated GM-induced AKI, oxidative stress, mitochondrial apoptosis, and inflammation. D-lim showed nephroprotective effects as reflected by the decrease in serum urea and creatinine and improvement of renal histopathological changes. D-lim alleviated GM-induced oxidative stress by increasing the activities of renal catalase, serum and renal glutathione peroxidase, and renal superoxide dismutase and decreasing renal malondialdehyde and serum nitric oxide levels. Intriguingly, D-lim suppressed mitochondrial apoptosis by considerably downregulating Bax and caspase-3 (Casp-3) mRNA and protein expressions and markedly enhancing Bcl2 mRNA and protein expressions. Furthermore, D-lim significantly decreases GM-induced inflammatory response through downregulation of NF-κB, IL-6, and TNF-α mRNA and/or protein expressions and decrease in renal myeloperoxidase activity. Finally, D-lim remarkably downregulated PCNA protein expression in the treated group compared with the GM group. In brief, this study showed that D-lim alleviated AKI following GM administration in rats, partially through its antioxidant, anti-inflammatory, and antiapoptotic activities as well as downregulation of PCNA expression.

Exposure to an Extended-Interval, High-Dose Gentamicin Regimen in the Neonatal Period Is Not Associated With Long-Term Nephrotoxicity

Objectives: To assess the association between gentamicin exposure and subclinical signs of nephrotoxicity in school children who were exposed to a high-dose gentamicin regimen in the neonatal period. Methods: Children receiving three or more doses (6 mg/kg) of gentamicin as neonates were invited to a follow-up in school age. We evaluated potential signs of subclinical nephrotoxicity with four validated urine biomarkers: protein-creatinine ratio (PCR), albumin-creatinine ratio (ACR), kidney injury molecule-1 (KIM-1), and N-acetyl-beta-D-glucosaminidase (NAG) normalized for urine creatinine (NAG-Cr). In addition, blood pressure was measured. The measures of gentamicin exposure were cumulative dose (mg/kg) and highest trough plasma concentration (TPC) in mg/L. We used logistic and linear regression and non-parametric kernel regression to analyze the relationship between gentamicin exposure and the urine biomarkers. Results: A total of 222 gentamicin exposed children were included. As neonates, the children were exposed to a median (interquartile range-IQR) cumulative gentamicin dose of 36 (26-42) mg/kg and the median (IQR) TPC was 1.0 (0.7-1.3) mg/L. At follow-up, 15 children (6.8%) had either one abnormal urine biomarker value (13 children) or two abnormal urine biomarker values (2 children). These 17 biomarker values were all marginally above the suggested upper cutoff, and included the following markers; KIM-1 (n = 2), NAC-Cr (n = 5), ACR (n = 6), and PCR (n = 4). All other 207 children had normal sets of all four urine biomarkers. One child had hypertension. There were no differences in gentamicin exposure, gestational age (GA) at birth or birth weight between the group of 15 children with one or two abnormal urine biomarker values compared to the other 207 children who had normal biomarker values. Using different regression analyses, we did not find any association between gentamicin exposure (cumulative dose and/or TPC) and the urine biomarker values. Conclusions: Exposure to an extended-interval, high-dose gentamicin regimen in the neonatal period was not associated with signs of subclinical nephrotoxicity in schoolchildren. We therefore suggest that the gentamicin treatment regimen evaluated in this study is safe in terms of long-term nephrotoxicity. Clinical Trial Registration: ClinicalTrials.gov, identifier: NCT03253614.

Chronotoxicity of Streptomycin-Induced Renal Injury in Mice

The aim of the present study was to investigate the "chronotoxicity" of streptomycin (SM) in relation to its circadian periodicity. Male ICR mice were injected intraperitoneally with SM (780 mg/kg, one shot) one of six time points throughout the day. Mortality was monitored until 14 d after the injection and clearly differed depending on the timing of the injection (i.e., mice were more sensitive to injection during the dark phase). Moreover, when mice were administered with non-lethal doses of SM (550 mg/kg, every 24 h for 3 d, in the light phase or dark phase), the levels of nephrotoxicity indicators (blood urea nitrogen and renal levels of malondialdehyde and cyclooxygenase-2) were significantly increased by the injection in the dark phase, but not in the light phase. These results suggested that SM showed clear chronotoxicity. Our current data indicated that chronotoxicology may provide valuable information on the importance of injection timings for evaluations of toxicity and undesirable side effects.

An updated review of protective effects of rosemary and its active constituents against natural and chemical toxicities

Natural and chemical toxic agents cause severe adverse effects on people's health in a variety of exposing ways. Herbal medications have taken into consideration as alternative safe treatments for toxicities. Rosmarinus officinalis also known as rosemary belongs to the Lamiaceae family. Rosemary and its constituents including carnosic acid, rosmarinic acid, and carnosol have a lot of benefits such as anti-inflammatory, antioxidant, anti-mutagenic, anti-bacterial, antiviral, antinociceptive, and neuroprotective activities. In this literate review, we focused on the protective effects of rosemary and its main compounds against natural and chemical toxicities in both in vitro and in vivo studies. The protective effects of rosemary and its components are mostly mediated through different mechanisms such as the inhibition of oxidative stress, reduction of inflammatory mediators including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-17 (IL-17), cyclooxygenase-2 (COX-2) and nuclear factor ĸB (NF-ĸB) as well as the modulation of apoptosis and mitogen-activated protein kinase (MAPK) signaling pathways.

Acute Kidney Injury in Septic Patients Treated by Selected Nephrotoxic Antibiotic Agents-Pathophysiology and Biomarkers-A Review

Acute kidney injury is a common complication in critically ill patients with sepsis and/or septic shock. Further, some essential antimicrobial treatment drugs are themselves nephrotoxic. For this reason, timely diagnosis and adequate therapeutic management are paramount. Of potential acute kidney injury (AKI) biomarkers, non-protein-coding RNAs are a subject of ongoing research. This review covers the pathophysiology of vancomycin and gentamicin nephrotoxicity in particular, septic AKI and the microRNAs involved in the pathophysiology of both syndromes. PubMED, UptoDate, MEDLINE and Cochrane databases were searched, using the terms: biomarkers, acute kidney injury, antibiotic nephrotoxicity, sepsis, miRNA and nephrotoxicity. A comprehensive review describing pathophysiology and potential biomarkers of septic and toxic acute kidney injury in septic patients was conducted. In addition, five miRNAs: miR-15a-5p, miR-192-5p, miR-155-5p, miR-486-5p and miR-423-5p specific to septic and toxic acute kidney injury in septic patients, treated by nephrotoxic antibiotic agents (vancomycin and gentamicin) were identified. However, while these are at the stage of clinical testing, preclinical and clinical trials are needed before they can be considered useful biomarkers or therapeutic targets of AKI in the context of antibiotic nephrotoxicity or septic injury.

Impact of deceased donor multidrug-resistant bacterial organisms on organ utilization

The extent to which donor multidrug-resistant organisms (MDROs) affect organ utilization remains unclear. We performed a retrospective cohort study at 4 transplant centers between 2015 and 2016 to evaluate this question. All deceased donors who donated at least one organ were included. Exposed donors had at least one MDRO on culture. Unexposed donors had no MDRO-positive cultures. Only cultures obtained during the donor's terminal hospitalization were evaluated. Multivariable regression was used to determine the association between donor MDRO and (1) number of organs transplanted per donor and (2) the match run at which each organ was accepted. Subsequently, we restricted the analysis to donors with MDR-Gram-negative (GN) organisms. Of 440 total donors, 29 (7%) donors grew MDROs and 7 (2%) grew MDR-GNs. There was no significant association between donor MDRO and either measure of organ utilization. However, donor MDR-GNs were associated with a significant reduction in the number of organs transplanted per donor (incidence rate ratio 0.43, 95% confidence interval [CI] 0.39-0.48, P < .01), and organs were accepted significantly further down the match list (relative count 5.08, 95% CI 1.64-15.68, P = .01). Though donor MDR-GNs were infrequent in our study, their growing prevalence could meaningfully reduce the donor pool over time.

Slower Elimination of Tofacitinib in Acute Renal Failure Rat Models: Contribution of Hepatic Metabolism and Renal Excretion

Tofacitinib is a Jak inhibitor developed as a treatment for rheumatoid arthritis. Tofacitinib is metabolized mainly through hepatic CYP3A1/2, followed by CYP2C11. Rheumatoid arthritis tends to increase renal toxicity due to drugs used for long-term treatment. In this study, pharmacokinetic changes of tofacitinib were evaluated in rats with gentamicin (G-ARF) and cisplatin-induced acute renal failure (C-ARF). The time-averaged total body clearance (CL) of tofacitinib in G-ARF and C-ARF rats after 1-min intravenous infusion of 10 mg/kg was significantly decreased by 37.7 and 62.3%, respectively, compared to in control rats. This seems to be because the time-averaged renal clearance (CL_R) was significantly lower by 69.5 and 98.6%, respectively, due to decreased creatinine clearance (CL_CR). In addition, the time-averaged nonrenal clearance (CL_NR) was also significantly lower by 33.2 and 57.4%, respectively, due to reduction in the hepatic CYP3A1/2 and CYP2C11 subfamily in G-ARF and C-ARF rats. After oral administration of tofacitinib (20 mg/kg) to G-ARF and C-ARF rats, both CL_R and CL_NR were also significantly decreased. In conclusion, an increase in area under plasma concentration-time curves from time zero to time infinity (AUC) of tofacitinib in G-ARF and C-ARF rats was due to the significantly slower elimination of tofacitinib contributed by slower hepatic metabolism and urinary excretion of the drug.

Renal safety of a single dose of gentamicin in patients with sepsis in the emergency department

OBJECTIVES

To determine the effect of a single dose of gentamicin on the incidence and persistence of acute kidney injury (AKI) in patients with sepsis in the emergency department (ED).

METHODS

We retrospectively studied patients with sepsis in the ED in three hospitals. Local antibiotic guidelines recommended a single dose of gentamicin as part of empirical therapy in selected patients in one hospital, whereas the other two hospitals did not. Multivariate analysis was used to evaluate the effect of gentamicin and other potential risk factors on the incidence and persistence of AKI after admission. AKI was defined according to the KDIGO (Kidney Disease Improving Global Outcomes) criteria.

RESULTS

Of 1573 patients, 571 (32.9%) received a single dose of gentamicin. At admission, 181 (31.7%) of 571 of the gentamicin-treated and 228 (22.8%) of 1002 of the non-gentamicin-treated patients had AKI (p < 0.001). After admission, AKI occurred in 64 (12.0%) of 571 patients who received gentamicin and in 82 (8.9%) of 1002 people in the control group (p 0.06). Multivariate analysis showed that shock (odds ratio (OR), 2.72; 95% CI, 1.31-5.67), diabetes mellitus (OR, 1.49; 95% CI, 1.001-2.23) and higher baseline (i.e. before admission) serum creatinine levels (OR, 1.007; 95% CI, 1.005-1.009) were associated with the development of AKI after admission, but not receipt of gentamicin (OR, 1.29; 95% CI, 0.89-1.86). Persistent AKI was rare in both the group that received gentamicin (16/260, 6.2%) and the group that did not (15/454, 3.3%, p 0.09).

CONCLUSIONS

With regard to renal function, a single dose of gentamicin in patients with sepsis in the ED is safe. The development of AKI after admission was associated with shock, diabetes mellitus and higher baseline creatinine level.

Mechanisms and pharmacokinetic/pharmacodynamic profiles underlying the low nephrotoxicity and ototoxicity of etimicin

Etimicin (ETM), a fourth-generation aminoglycosides (AGs), is now widely clinically used in China due to its high efficacy and low toxicity. However, the mechanisms underlying its low nephrotoxicity and ototoxicity remain unclear. In the present study we compared the antibacterial and toxicity profiles of etimicin, gentamicin (GM, a second-generation AG), and amikacin (AMK, a third-generation AG), and investigated their pharmacokinetic properties in the toxicity target organs (kidney and inner ear) and subcellular compartments. We first demonstrated that ETM exhibited superior antibacterial activities against clinical isolates to GM and AMK, and it exerted minimal nephrotoxicity and ototoxicity in rats following multi-dose administration. Then, we conducted pharmacokinetic studies in rats, showed that the three AGs accumulated in the kidney and inner ear with ETM being distributed to a lesser degree in the two toxicity target organs as compared with GM and AMK high-dose groups. Furthermore, we conducted in vitro experiments in NRK-52E rat renal tubular epithelial cells and HEI-OC1 cochlear hair cells, and revealed that all the three AGs were distributed predominantly in the mitochondria with ETM showing minimal accumulation; they not only directly inhibited the activity of mitochondrial complexes IV and V but also inhibited mitochondrial function and its related PGC-1α-NRF1-TFAM pathway; ETM caused minimal damage to the mitochondrial complex and mitochondrial biogenesis. Our results demonstrate that the minimal otonephrotoxicity of ETM results from its lesser accumulation in mitochondria of target cells and subsequently lesser inhibition of mitochondrial function. These results provide a new strategy for discovering novel AGs with high efficacy and low toxicity.

A Multiparametric Assay Platform for Simultaneous In Vivo Assessment of Pronephric Morphology, Renal Function and Heart Rate in Larval Zebrafish

Automated high-throughput workflows allow for chemical toxicity testing and drug discovery in zebrafish disease models. Due to its conserved structural and functional properties, the zebrafish pronephros offers a unique model to study renal development and disease at larger scale. Ideally, scoring of pronephric phenotypes includes morphological and functional assessments within the same larva. However, to efficiently upscale such assays, refinement of existing methods is required. Here, we describe the development of a multiparametric in vivo screening pipeline for parallel assessment of pronephric morphology, kidney function and heart rate within the same larva on a single imaging platform. To this end, we developed a novel 3D-printed orientation tool enabling multiple consistent orientations of larvae in agarose-filled microplates. Dorsal pronephros imaging was followed by assessing renal clearance and heart rates upon fluorescein isothiocyanate (FITC)-inulin microinjection using automated time-lapse imaging of laterally positioned larvae. The pipeline was benchmarked using a set of drugs known to induce developmental nephrotoxicity in humans and zebrafish. Drug-induced reductions in renal clearance and heart rate alterations were detected even in larvae exhibiting minor pronephric phenotypes. In conclusion, the developed workflow enables rapid and semi-automated in vivo assessment of multiple morphological and functional parameters.

Chemical Modifications Reduce Auditory Cell Damage Induced by Aminoglycoside Antibiotics

Although aminoglycoside antibiotics are effective against Gram-negative infections, these drugs often cause irreversible hearing damage. Binding to the decoding site of the eukaryotic ribosomes appears to result in ototoxicity, but there is evidence that other effects are involved. Here, we show how chemical modifications of apramycin and geneticin, considered among the least and most toxic aminoglycosides, respectively, reduce auditory cell damage. Using molecular dynamics simulations, we studied how modified aminoglycosides influence the essential freedom of movement of the decoding site of the ribosome, the region targeted by aminoglycosides. By determining the ratio of a protein translated in mitochondria to that of a protein translated in the cytoplasm, we showed that aminoglycosides can paradoxically elevate rather than reduce protein levels. We showed that certain aminoglycosides induce rapid plasma membrane permeabilization and that this nonribosomal effect can also be reduced through chemical modifications. The results presented suggest a new paradigm for the development of safer aminoglycoside antibiotics.

Development of a Novel Pharmaceutical Formula of Nanoparticle Lipid Carriers of Gentamicin/α-Tocopherol and In Vivo Assessment of the Antioxidant Protective Effect of α-Tocopherol in Gentamicin-Induced Nephrotoxicity

Gentamicin is a potent antibiotic with a nephrotoxicity drawback which limits its use. D-α-tocopherol polyethylene glycol succinate (α-tocopherol) is widely used as a surfactant and have potent antioxidant properties. This study aimed to assess the protective effect of α-tocopherol on gentamicin-induced nephrotoxicity by loading gentamicin on nanostructured lipid carriers (NLC). In vivo, the product was administered intravenously to three groups of rabbits (control, gentamicin and gentamicin/α-tocopherol NLC) for 10 consecutive days. Blood was collected on days 1, 5 and 10 to assess renal function. A significant difference in all plasma parameters related to kidney function were observed in the gentamicin group compared to the control by day 5 and 10, confirming the nephrotoxicity effect. On the other hand, the same parameter levels of the NLC group were significantly different compared to the gentamicin group, confirming the protective effect on kidney function. Gentamicin also caused significant decreases in plasma levels of glutathione sulfhydryl (GSH) and superoxide dismutase (SOD) activity. However, gentamicin-α-tocopherol NLC significantly elevates both plasma levels of GSH as well as SOD activity. The present work indicates that, loading of gentamicin on NLC by using α-tocopherol, is an innovative strategy to protect against aminoglycoside-induced nephrotoxicity due to its antioxidant activity.

Aqueous garlic extract supresses experimental gentamicin induced renal pathophysiology mediated by oxidative stress, inflammation and Kim-1

BACKGROUND

Gentamicin (Gent) has rapid & high bactericidal action in addition to its cheap price. Nevertheless, 30% of gentamicin-treated patients develop nephrotoxicity.

OBJECTIVE

To explore the probable nephroprotective effects of the aqueous garlic extract (AGE) & to elucidate its underlying mechanisms via monitoring proinflammatory cytokines as tumer necrosis factor (TNF-α), interleukin 6 (IL-6) and interferon-γ (INF-γ), oxidative stess markers as malondialdehyde (MDA) & superoxide dismutase (SOD) & kidney injury molecule (Kim-1) as a promising early specific biomarker of renal dysfunction.

METHODS

32 adult male rats were divided into 4 equal groups treated for 21 days as: normal control group received normal saline orally, AGE-treated group received AGE at 250 mg/kg/day orally, Gent-treated group received Gent-sulphate intraperitoneal injection at 80 mg/kg /day, and AGE & Gent cotreated group received AGE and Gent concomitantly in the same previous doses. Serum urea, creatinine, glomerular filteration rate (GFR), systolic (SBP) and diastolic blood pressure (DBP), TNF-α, IL-6, INF-γ, MDA and SOD and Kim-1 mRNA expression were evaluated in kidney tissue homogenate. Renal cortex sections stained with Haematoxylin & eosin (H&E) were examined.

RESULTS

AGE is nephroprotective through significantly reducing serum urea, creatinine, SBP and DBP, TNF-α, IL-6, INF-γ and MDA (the main product of lipid peroxidation), decreasing expression of Kim-1 mRNA in renal tissue and increasing level of GFR, the natural antioxidant SOD and improving renal histological features of Gent-treated rats.

CONCLUSION

AGE normalizes Gent-induced renal dysfunction. Their co-administration is a plausible advice, although the therapeutic efficiency of Gent was not investigated.

Renoprotective effects of stevia (Stevia rebaudiana Bertoni), amlodipine, valsartan, and losartan in gentamycin-induced nephrotoxicity in the rat model: Biochemical, hematological and histological approaches

The current study investigated the renoprotective effects of stevia, angiotensin-II type 1 receptor (AT1) blocker and calcium (Ca2+) channel blocker in gentamycin-induced nephrotoxicity in rat models. Six groups of male Sprague-Dawley rats of eight weeks old were taken for the experiment: sham control, nephrotoxicity, treatment with amlodipine (4 mg/kg/day); stevia (200 mg/kg/day); losartan (15 mg/kg/day) and valsartan (5 mg/kg/day), accordingly. The blood sample was taken for the assessment of renal and hepatic-functional variables like serum creatinine, blood urea, BUN and SGPT, SGOT, and total serum bilirubin. Hematological parameters were also examined. Histological examination has been done on kidneys and liver. Alterations of the body weight and the organ's weight were documented. Treatment with stevia and valsartan significantly decreased serum creatinine levels. A reduction of liver enzymes, and total serum bilirubin levels were observed in all the treatment groups. Treatment with valsartan and amlodipine, remarkably and stevia, mildly reduced the renal tissue damage, inflammation, and tubular necrosis. However, the present study demonstrated that losartan treatment aggravated kidney damage by increasing protein cast, calcification, tubular necrosis, and injury. This comparison indicated that both stevia and valsartan have beneficial renoprotective effect and valsartan offers a better treatment option in renal damage over losartan.

Pharmacological properties of Rheum turkestanicum Janisch

Medicinal herbs have been increasingly used worldwide for diseases prevention and treatment. Rheum turkestanicum Janisch. is a perennial shrub of the Polygonaceae family. Genus Rheum includes more than 60 species growing around the world which are used in foods and traditional medicines. R. turkestanicum is believed to be able to improve different kinds of disorders including diabetes, hypertension, jaundice and cancer. In recent years, this medicinal plant has been a subject of many experimental studies to document its health-beneficial properties. These studies have revealed antidiabetic, anticancer, nephroprotective, cardioprotective, and hepatoprotective properties of R. turkestanicum. The presence of flavonoids (e.g. epicatechin and quercetin) and anthraquinones (e.g. chrysophanol, physcion, and emodin) in R. turkestanicum justifies its health-beneficial effects. Nevertheless, possible therapeutic applications and safety of this plant still need to be elucidated in further clinical studies.

The footprints of mitochondrial impairment and cellular energy crisis in the pathogenesis of xenobiotics-induced nephrotoxicity, serum electrolytes imbalance, and Fanconi's syndrome: A comprehensive review

Fanconi's Syndrome (FS) is a disorder characterized by impaired renal proximal tubule function. FS is associated with a vast defect in the renal reabsorption of several chemicals. Inherited and/or acquired conditions seem to be connected with FS. Several xenobiotics including many pharmaceuticals are capable of inducing FS and nephrotoxicity. Although the pathological state of FS is well described, the exact underlying etiology and cellular mechanism(s) of xenobiotics-induced nephrotoxicity, serum electrolytes imbalance, and FS are not elucidated. Constant and high dependence of the renal reabsorption process to energy (ATP) makes mitochondrial dysfunction as a pivotal mechanism which could be involved in the pathogenesis of FS. The current review focuses on the footprints of mitochondrial impairment in the etiology of xenobiotics-induced FS. Moreover, the importance of mitochondria protecting agents and their preventive/therapeutic capability against FS is highlighted. The information collected in this review may provide significant clues to new therapeutic interventions aimed at minimizing xenobiotics-induced renal injury, serum electrolytes imbalance, and FS.

Drug-induced Glomerulonephritis: The Spectre of Biotherapeutic and Antisense Oligonucleotide Immune Activation in the Kidney

Prevalence of immune-mediated glomerulonephritis has increased in preclinical toxicity studies, with more frequent use of biotherapeutic agents (especially antigenic humanized molecules) and antisense oligonucleotide (ASO) therapies. Immune complex disease affects a small number of study monkeys, often correlates with antidrug antibody (ADA) titers, and occurs at a dose that favors immune complex formation or impedes clearance. While preclinical glomerulonephritis often fails to correlate with evidence of glomerular or vascular injury in human clinical trials and is not considered predictive, additional animal investigative immunohistochemical work may be performed to substantiate evidence for immune complex pathogenesis. While ADA is most commonly encountered as a predisposing factor with biotherapeutic agents, complement activation may occur without circulating complexes, and other mechanisms of non-ADA immune-mediated glomerulonephritis have been observed including nonendogenous immune aggregates and immunoregulatory pharmacology. Although glomerulonephritis associated with oligonucleotide therapies has been noted occasionally in preclinical studies and more rarely with human patients, pathophysiologic mechanisms involved appear to be different between species and preclinical cases are not considered predictive for humans. ADA is not involved in oligonucleotide-associated cases, and complement fixation plays a more important role in monkeys. Recent screening of ASOs for proinflammatory activity appears to have decreased glomerulonephritis incidence preclinically.

Protective effect of Rotula aquatica Lour against gentamicin induced oxidative stress and nephrotoxicity in Wistar rats

Gentamicin is an aminoglycoside antibiotic widely used for the treatment of life-threatening infections caused by Gram-negative bacteria. The use of gentamicin was limited due to its ototoxic and nephrotoxic adverse effects. The current study was designed to evaluate the protective effect of ethyl acetate fraction from Rotula aquatica (EFRA) against gentamicin induced nephrotoxicity. The antioxidant enzymes status, lipid peroxidation, nitrate and ROS level, serum markers like creatinine, Urea, BUN were estimated in the present study. The histopathological analysis of renal tissues was done by H&E and PAS staining. The mRNA level expression of KIM-1, NF-κB, TNF- α, and IL-6 were measured by semi-quantitative reverse transcription-polymerase chain reaction. The changes in antioxidant parameters were restored by the treatment of EFRA at different dose (50 mg/kg bwt, 100 mg/kg bwt). The serum parameters, ROS, MDA and nitrate level were decreased by administration of EFRA. The EFRA ameliorates histological changes associated with gentamicin induced nephrotoxicity. The mRNA level expression of KIM-1, NF-κB, TNF- α, and IL-6 were downregulated in EFRA treated groups. The results from present study reveals the role of EFRA as good anti-inflammatory and nephro protective drug.

Effect of Helichrysum plicatum DC. subsp. plicatum ethanol extract on gentamicin-induced nephrotoxicity in rats

The aim of this study was to evaluate the possible therapeutic or protective effects of Helichrysum plicatum DC. subsp. plicatum ethanol extract (HPE) against gentamicin-induced nephrotoxicity. Thirty-six Sprague Dawley male rats weighing between 200 and 250 g were used as live material. They were formed into six groups containing 6 rats each and were allowed to adapt to laboratory conditions for 7 d. Group I: control, 5% DMSO intraperitoneal (i.p.); Group II: HPE 100 mg/(kg·d) i.p.; Group III: HPE 200 mg/(kg·d) i.p.; Group IV: gentamicin as 80 mg/(kg·d) i.p.; Group V: gentamicin as 80 mg/(kg·d) i.p.+HPE 100 mg/(kg·d) i.p.; and Group VI: gentamicin as 80 mg/(kg·d) i.p.+HPE 200 mg/(kg·d) i.p. for 8 d. Following treatment, serum, liver, and kidney tissues were used to assess blood urea nitrogen (BUN), creatinine, enzymatic and non-enzymatic antioxidants, and lipid peroxidation. Gentamicin significantly increased serum BUN, creatinin, and liver and kidney levels of malondialdehyde (MDA). It also decreased the activity of catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD). Treatment with the HPE 100 mg/kg reversed gentamicin-induced alterations as evidenced by decreased serum BUN and creatinin, liver and kidney oxidant marker, and tubular necrosis as well as by an increase in antioxidant enzymes. It was found that HPE 200 mg/kg significantly increased liver and kidney tissue MDA levels in nephrotoxicity in rats. As a result, these findings support the proposition that HPE in 100 mg/kg dose demonstrates in the kidney and liver as free radicals and scavenger to prevent the toxic effects of gentamicin in both the biochemical and histopathology parameters.

α-Tocopherol Reduces Morphological Changes and Oxidative Stress during Gentamicin-Induced Acute Renal Failure

We studied the effect of α-tocopherol on gentamicin-induced morphological and functional changes in the kidneys of Wistar rats. Special attention was paid to the ability of α-tocopherol administered in combination with gentamicin to correct ultrastructural changes in the glomerular basal membrane and tubules. Combined treatment with α-tocopherol (100 mg/kg) and gentamicin (100 mg/kg) led to correction of histopathological and biochemical changes and oxidative injury to the kidneys induced by this antibiotic.

Troxerutin down-regulates KIM-1, modulates p38 MAPK signaling, and enhances renal regenerative capacity in a rat model of gentamycin-induced acute kidney injury

Troxerutin enhances renal tissue regeneration, improves renal function, and decreases renal tissue injury in gentamycin-treated rats.

In Vitro Assessment of Gentamicin Cytotoxicity on the Selected Mammalian Cell Line (Vero cells)

The aim of this study was to evaluate the in vitro cytotoxicity of different concentrations (500-7500 μg/mL) of gentamicin - GENT (aminoglycoside antibiotic) on the selected mammalian cell line (Vero - cell line from African green monkey kidney). Analysis of the cell morphological changes was microscopically evaluated (magnification × 400). Quantification of Ca, Mg and total proteins was performed using spectrophotometry on device Rx Monza (Randox). Quantification of Na, K and Cl was performed on the automatic analyzer EasyLyte. The cell viability was assessed using the metabolic mitochondrial MTT test. Vero cells were able to survive at concentrations of 500 (89.21 %), 1000 (79.54 %) and 2000 μg/mL (34.59 %). We observed statistically significant decrease of vital cell content at concentrations of 2000, 4500, 7500 μg/mL against control group. Vero cell line slightly reacted to the presence of GENT but total proteins and mineral parameters were not significantly affected. Vero cells were highly sensitive to GENT with a significant decrease of viability at concentrations of 2000 and 4500 μg/mL (P < 0.001). Our data reveal that GENT has a significant cytotoxic and adverse effect on the cell viability.

Nebulized Versus IV Amikacin as Adjunctive Antibiotic for Hospital and Ventilator-Acquired Pneumonia Postcardiac Surgeries: A Randomized Controlled Trial

OBJECTIVE

Nebulized antibiotics offer high efficacy due to significant local concentrations and safety with minimal blood levels. This study evaluates the efficacy and nephrotoxicity of nebulized versus IV amikacin in postcardiothoracic surgical patients with nosocomial pneumonia caused by multidrug-resistant Gram- negative bacilli.

DESIGN

Prospective, randomized, controlled study on surgical patients divided into two groups.

SETTING

Postcardiac surgery ICU.

INTERVENTIONS

The first gtroup was administered IV amikacin 20 mg/kg once daily. The second group was prescribed amikacin nebulizer 400 mg twice daily. Both groups were co-administered IV piperacillin/tazobactam empirically.

PATIENTS

Recruited patients were diagnosed by either hospital-acquired pneumonia or ventilator-associated pneumonia where 56 (42.1%) patients were diagnosed with hospital-acquired pneumonia, 51 (38.34%) patients were diagnosed with early ventilator-associated pneumonia, and 26 (19.54%) patients with late ventilator-associated pneumonia.

MEASUREMENTS AND MAIN RESULTS

Clinical cure in both groups assessed on day 7 of treatment was the primary outcome. Efficacy was additionally evaluated through assessing the length of hospital stay, ICU stay, days on amikacin, days on mechanical ventilator, mechanical ventilator-free days, days to reach clinical cure, and mortality rate. Lower nephrotoxicity in the nebulized group was observed through significant preservation of kidney function (p < 0.001). Although both groups were comparable regarding length of hospital stay, nebulizer group showed shorter ICU stay (p = 0.010), lower number of days to reach complete clinical cure (p = 0.001), fewer days on mechanical ventilator (p = 0.035), and fewer days on amikacin treatment (p = 0.022).

CONCLUSION

Nebulized amikacin showed better clinical cure rates, less ICU stay, and fewer days to reach complete recovery compared to IV amikacin for surgical patients with nosocomial pneumonia. It is also a less nephrotoxic option associated with less deterioration in kidney function.