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

Krüppel-like factor 4 modulates the miR-101/COL10A1 axis to inhibit renal fibrosis after AKI by regulating epithelial-mesenchymal transition

Acute kidney injury (AKI) can progress to renal fibrosis and chronic kidney disease (CKD), which reduces quality of life and increases the economic burden on patients. However, the molecular mechanisms underlying renal fibrosis following AKI remain unclear. This study tested the hypothesis that the Krüppel-like factor 4 (KLF4)/miR-101/Collagen alpha-1X (COL10A1) axis could inhibit epithelial-mesenchymal transition (EMT) and renal fibrosis after AKI in a mouse model of ischemia-reperfusion (I/R)-induced renal fibrosis and HK-2 cells by gene silencing, overexpression, immunofluorescence, immunohistochemistry, real-time quantitative PCR, Western blotting, dual-luciferase reporter assay, fluorescence in situ hybridization (FISH) and ELISA. Compared with the Sham group, I/R induced renal tubular and glomerular injury and fibrosis, and increased the levels of BUN, serum Scr and neutrophil gelatinase-associated lipocalin (NGAL), Col10a1 and Vimentin expression, but decreased E-cadherin expression in the kidney tissues of mice at 42 days post-I/R. Similarly, hypoxia promoted fibroblastic morphological changes in HK-2 cells and enhanced NGAL, COL10A1, Vimentin, and α-SMA expression, but reduced E-cadherin expression in HK-2 cells. These pathological changes were significantly mitigated in COL10A1-silenced renal tissues and HK-2 cells. KLF4 induces miR-101 transcription. More importantly, hypoxia upregulated Vimentin and COL10A1 expression, but decreased miR-101, KLF4, and E-cadherin expression in HK-2 cells. These hypoxic effects were significantly mitigated or abrogated by KLF4 over-expression in the HK-2 cells. Our data indicate that KLF4 up-regulates miR-101 expression, leading to the downregulation of COL10A1 expression, inhibition of EMT and renal fibrosis during the pathogenic process of I/R-related renal fibrosis.

The ameliorative effect of vinpocetine against gentamicin-induced uterine-injury in rats involves the inflammasome/caspase-1/IL-1β pathway

BACKGROUND

There is limited data regarding the hazardous effect of gentamicin (GM) on the uterus and whether or not vinpocetine (Vinpo) ameliorates it. The present study aimed to identify the possible protective effect of Vinpo in GM-induced uterine injury in rats.

METHODS

Female rats were assorted in control-group, Vinpo-group, GM-group, and Vinpo plus GM group. Serum and uterine GM concentration were measured. Uterine oxidative stress parameters besides inflammatory and apoptotic biomarkers were evaluated. Uterine histopathological examination and interlukin-1beta (IL-1β) immune-histochemical study were detected.

RESULTS

GM significantly increased uterine oxidative stress, inflammatory and apoptotic biomarkers. Histopathological picture of uterine damage and increased IL-1β immunoexpression were detected. Vinpo significantly ameliorated the distributed GM concentration, oxidative stress, inflammatory and apoptotic biomarkers with a prompt improvement in histopathological picture and a decrease in IL-1β immunoexpression.

CONCLUSION

Vinpo protective effect against GM-induced uterine injury involves modulation of inflammasome/caspase-1/IL-1β signaling pathway.

Empagliflozin alleviates diabetes-induced cognitive impairments by lowering nicotinamide adenine dinucleotide phosphate oxidase-4 expression and potentiating the antioxidant defense system in brain tissue of diabetic rats

BACKGROUND

Diabetes-induced cognitive impairment is a major challenge in patients with uncontrolled diabetes mellitus. It has a complicated pathophysiology, but the role of oxidative stress is central. Therefore, the use of antidiabetic drugs with extra-glycemic effects that reduce oxidative damage may be a promising treatment option.

METHODS

Male Wistar rats were randomly divided into four groups as normal, normal treated, diabetic and diabetic treated (n = 8 per group). Type 1 diabetes was induced by a single intraperitoneal dose of streptozotocin (STZ) (40 mg/kg). Two treatment groups received empagliflozin for 5 weeks (20 mg/kg/po). Cognitive ability was evaluated using open field, Elevated Plus Maze (EPM) and the Morris Water Maze (MWM) tests at study completion. Blood and brain tissue samples were collected - and analysis for malondialdehyde (MDA) and glutathione (GLT) content and catalase (CAT) and superoxide dismutase (SOD) enzyme activity were performed. Additionally, expression of nicotinamide adenine dinucleotide phosphate oxidase-4 (Nox-4) enzyme in brain tissue was analyzed using RT-PCR.

RESULTS

STZ increased blood glucose and induced diabetes with oxidative stress by lowering the antioxidant system potency and increasing Nox-4 expression after 5-weeks in brain tissue accompanied by reduction in cognitive performance. Also, diabetes induced anxiety-like behavior and impaired spatial memory in MWM, EPM and open field tests. However, empagliflozin reversed these changes, improving SOD and CAT activity, GLT content and reducing Nox-4 expression and MDA concentration in brain tissue while improving cognitive ability. It reduced anxiety and depression-related activities. It also improved spatial memory in MWM test.

CONCLUSION

Uncontrolled diabetes negatively impacts mental function and impairs learning and cognitive performance via oxidative stress induction, the Nox-4 enzyme playing a central role. Empagliflozin reverses these effects, improving cognitive ability via promoting the anti-oxidative system and damping Nox-4 free radical generator enzyme expression. Therefore, empagliflozin is a promising treatment, providing both antidiabetic and extra-glycemic benefits for improving brain function in the diabetic milieu.

Dihydromyricetin protects against gentamicin-induced nephrotoxicity via upregulation of renal SIRT3 and PAX2

AIM

Gentamicin-induced nephrotoxicity limits its widespread use as an effective antibacterial agent. Oxidative stress, inflammatory cytokines and apoptotic cell death are major participants in gentamicin-induced nephrotoxicity. We therefore, investigated whether dihydromyricetin (DHM), the antioxidant and anti-inflammatory flavonoid, could protect against the nephrotoxic effects of gentamicin.

METHODS

Male Wistar rats administrated gentamicin (100 mg/kg/day, i.p.) for 8 days. DHM (400 mg/kg, p.o.) was concurrently given with gentamicin for 8 days. Control group received the vehicle of DHM and gentamicin. Histopathological examinations, biochemical measurements and immunohistochemical analyses were done at the end of the study.

KEY FINDINGS

Treatment with DHM improved the gentamicin induced deterioration of renal functions; serum levels of urea, creatinine and cystatin-C as well as urinary levels of Kim-1 and NGAL, the sensitive indicators for early renal damage, were declined. Additionally, DHM abrogated gentamicin-induced changes in kidney morphology. These nephroprotective effects were possibly mediated via decreasing renal gentamicin buildup, activating the antioxidant enzymes GSH, SOD and CAT and decreasing lipid peroxidation and nitric oxide levels. Further, DHM suppressed renal inflammation and apoptotic cell death by decreasing the expression of nuclear factor-kappa B (NF-κB), TNF-alpha and caspase-3. These effects were correlated to the upregulation of renal SIRT3 expression. Also, DHM activated the regeneration and replacement of injured tubular cells with new ones via enhancing PAX2 expression.

SIGNIFICANCE

DHM is a promising therapeutic target that could prevent acute renal injury induced by gentamicin and help renal tubular cells to recover through its antioxidant, anti-inflammatory and antiapoptotic properties.

Protective effects of empagliflozin on methotrexate induced hepatotoxicity in rats

Methotrexate (MTX), a folic acid antagonist, is commonly prescribed as a cytotoxic drug to treat several conditions such as leukemia and inflammation-related diseases, including rheumatoid arthritis and psoriasis. However, its use in clinical practice has been limited due to its fatal side effects, especially hepatotoxicity. Empagliflozin is a sodium-glucose cotransporter 2 (SGLT2) inhibitor that has recently been reported to exhibit anti-inflammatory and anti-oxidative properties. This study was aimed to evaluate the effect of Empagliflozin on liver injury induced by MTX in rats. The rats were divided into five groups as control, MTX (20 mg/kg; i.p.), Empagliflozin (30 mg/kg/day; i.p.), MTX and Empagliflozin (10 and 30 mg/kg/day; i.p.). Histopathologic alterations were examined for assessment of the liver injury. Furthermore, the levels of tissue malondialdehyde (MDA) and activity of anti-oxidative enzymes, superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase, as well as serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were evaluated. Our results revealed that treatment with Empagliflozin significantly improved histopathologic alterations, and elevated levels of AST and ALT induced by MTX administration. Additionally, altered activities of SOD, GPx, and catalase were significantly improved followed by Empagliflozin treatment. However, the higher dose of Empagliflozin was observed to have several benefits compared to the lower dose. Our data suggest that Empagliflozin might possess a protective role against MTX-induced hepatotoxicity by inhibiting oxidative stress in liver tissue.

Empagliflozin inhibits neointimal hyperplasia through attenuating endothelial-to-mesenchymal transition via TAK-1/NF-κB pathway

OBJECTIVE

To investigate whether empagliflozin could prevent injury-induced vascular neointimal hyperplasia and to further explore its mechanism.

METHODS

Male C57BL/6J mice were divided into two groups with or without the empagliflozin treatment, and carotid ligation injury was performed to induce neointimal hyperplasia. The injured carotid arteries were collected for Western blotting (WB), histology and immunofluorescence analysis after four weeks. The inflammatory responses were analyzed by qRT-PCR to detect the inflammatory gene mRNA expression. To further explore its mechanism, HUVECs were treated with TGFβ-1 to induce EndMT followed by empagliflozin or vehicle treatment in vitro. A23187 (Calcimycin), an agonist of NF-κB signaling was used in the experiment.

RESULTS

The wall thickness and the neointima area was significantly reduced in the empagliflozin treatment group on day 28 after artery ligation. The Ki-67 positive cells were 28.33 ± 12.66% and 48.83 ± 10.41% in the empagliflozin-treated group and control group, respectively (P < 0.05). The mRNA expression levels of the inflammatory genes and inflammatory cells were decreased in the empagliflozin treatment group, as well as the MMP2 and MMP9. Meanwhile, empagliflozin can significantly reduce the migratory ability of inflammatory-treated HUVECs. The CD31 was increased in the TGFβ1+empagliflozin group, whereas the FSP-1, phosphorylation of TAK-1 (p-TAK-1) and phosphorylation of NF-κB (p- NF-κB) expression level were decreased, compared to the control group without empagliflozin treatment. However, the expression level of FSP-1 and p-NF-κB were reversed after co-treatment with A23187, whereas the (p-TAK-1 expression level was without any significant difference.

CONCLUSION

Empagliflozin inhibits the inflammation-induced EndMT via the TAK-1/NF-κB signaling pathway.

Sodium Glucose Cotransporter-2 Inhibitor Empagliflozin Increases Antioxidative Capacity and Improves Renal Function in Diabetic Rats

INTRODUCTION

There are several pathologic mechanisms involved in diabetic nephropathy, but the role of oxidative stress seems to be one of the most important. Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a relatively new class of antidiabetic drugs that might also have some other effects in addition to lowering glucose. The aim of this study was to evaluate the possible effects of the SGLT2 inhibitor empagliflozin on oxidative stress and renal function in diabetes.

METHODS

Male Wistar rats were randomly divided into four groups: control, control-treated, diabetic, and diabetic-treated (n = 8 per group). Diabetes was induced by a single intraperitoneal dose of streptozotocin (50 mg/kg). The treated animals received empagliflozin for 5 weeks (20 mg/kg/day/po). All groups were sacrificed on the 36th day, and blood and tissue samples were collected. Serum levels of urea, uric acid, creatinine, and glucose levels were determined. The level of malondialdehyde (MDA) and glutathione (GLT), as well as the activity of catalase (CAT) and superoxide dismutase (SOD), was measured in all groups. Data were analyzed using one-way Anova and paired T-tests, and p ≤ 0.05 was considered significant.

RESULTS

Diabetes significantly increased urea (p < 0.001), uric acid (p < 0.001), and creatinine (p < 0.001) in the serum, while the activities of CAT (p < 0.001) and SOD (p < 0.001) were reduced. GLT was also reduced (p < 0.001), and MDA was increased (p < 0.001) in non-treated animals. Treatment with empagliflozin improved renal function, as shown by a reduction in the serum levels of urea (p = 0.03), uric acid (p = 0.03), and creatinine (p < 0.001). Empagliflozin also increased the antioxidant capacity by increasing CAT (p = 0.035) and SOD (p = 0.02) activities and GLT content (p = 0.01) and reduced oxidative damage by lowering MDA (p < 0.001).

CONCLUSIONS

It seems that uncontrolled diabetes induces renal insufficiency by decreasing antioxidant defense mechanisms and inducing oxidative stress. Empagliflozin might have additional benefits in addition to lowering glucose--reversing these processes, improving antioxidative capacity, and improving renal function.

Diacerein modulates TLR4/ NF-κB/IL-1β and TRPC1/CHOP signalling pathways in gentamicin-induced parotid toxicity in rats

The present study aimed to identify the possible protective effect of diacerein (DIA) on gentamicin (GNT)-induced parotid toxicity in rats. DIA was administered in the presence and absence of GNT. Thirty-two Wistar adult male rats were randomly arranged into four groups: control, DIA (50 mg/kg/day), GNT (100 mg/kg) and GNT+DIA groups for 8 days. Parotid oxidative stress parameters, besides inflammatory and apoptotic biomarkers, were evaluated. Salivary flow rate, transient receptor potential canonical 1 (TRCP1), and C/EBP homologous protein (CHOP) in parotid tissue were measured. A parotid histopathological examination and an interleukin-1 beta (IL-1β) immunohistochemical study were also performed. GNT significantly increased parotid oxidative stress, inflammatory, apoptotic and CHOP biomarkers with decreased salivary flow rate and TRCP1 level. A histopathological picture of parotid damage and high IL-1β immunoexpression were detected. DIA significantly normalized the distributed oxidative, inflammatory and apoptotic indicators, CHOP and TRCP1, with a prompt improvement in the histopathological picture and a decrease in IL-1β immunoexpression. These results reported that DIA protects against GNT-induced parotid toxicity via modulation of TLR4/NF-κB/IL-1β and TRPC1/CHOP signalling pathways.

Shikonin Alleviates Gentamicin-Induced Renal Injury in Rats by Targeting Renal Endocytosis, SIRT1/Nrf2/HO-1, TLR-4/NF-κB/MAPK, and PI3K/Akt Cascades

Gentamicin causes kidney injury due to its accumulation in proximal tubule epithelial cells via the megalin/cubilin/CLC-5 complex. Recently, shikonin has been shown to have potential anti-inflammatory, antioxidant, antimicrobial, and chloride channel-inhibiting effects. The current study investigated the alleviation of gentamicin-induced renal injury by shikonin while preserving its bactericidal effect. Nine-week-old Wistar rats were administered 6.25, 12.5, and 25 mg/kg/day shikonin orally, one hour after the i.p. injection of 100 mg/kg/day gentamicin for seven days. Shikonin significantly and dose-dependently alleviated gentamicin-induced renal injury, as revealed by restoring normal kidney function and histological architecture. Furthermore, shikonin restored renal endocytic function, as indicated by suppressing the elevated renal megalin, cubilin, and CLC-5 and enhancing the reduced NHE3 levels and mRNA expressions induced by gentamicin. These potentials could be attributed to the modulation of the renal SIRT1/Nrf2/HO-1, TLR-4/NF-κB/MAPK, and PI3K/Akt cascades, which enhanced the renal antioxidant system and suppressed renal inflammation and apoptosis, as indicated by enhancements of SIRT1, Nrf2, HO-1, GSH, SOD, TAC, Iκb-α, Bcl-2, PI3K, and Akt levels and mRNA expressions, with reduction of TLR-4, NF-κB, MAPK, IL-1β, TNF-α, MDA, iNOS, NO, cytochrome c, caspase-3, Bax levels, and Bax/Bcl-2 ratio. Therefore, shikonin is a promising therapeutic agent for alleviating gentamicin-induced renal injury.