Wheat germ and vitamin E decrease BAX/BCL-2 ratio in rat kidney treated with gentamicin

Investigation of the effects of crocin on inflammation, oxidative stress, apoptosis, NF-κB, TLR-4 and Nrf-2/HO-1 pathways in gentamicin-induced nephrotoxicity in rats

The primary limitation of gentamicin (Gm) treatment is its potential to induce nephrotoxicity, which can restrict both its duration and efficacy. This study aims to investigate the protective effects of Crocin (Cr) against Gm-induced nephrotoxicity and its underlying mechanisms, including inflammation, apoptosis, TLR-4, Nrf-2/HO-1 pathways. 36 Sprague Dawley rats were divided into 6 groups for the study. Group I received only saline. Groups II and III were administered 25 and 50 mg/kg of crocin, respectively. Group IV was treated with 80 mg/kg of Gm. Groups V and VI received 25 and 50 mg/kg of crocin, respectively, in addition to Gm administration. Crocin demonstrated protective effects on kidney tissue. It down-regulated the genes NF-κB, COX-2, TLR-4, Bax, and Caspase-3, while up-regulating Bcl-2, Nrf-2, and HO-1. In conclusion, these findings hold promise for the prevention of Gm-induced nephrotoxicity through the modulation of the Nrf-2/HO-1 pathway.

Ameliorative Impacts of Wheat Germ Oil against Ethanol-Induced Hepatic and Renal Dysfunction in Rats: Involvement of Anti-Inflammatory, Anti-Apoptotic, and Antioxidant Signaling Pathways

Wheat germ oil (WGO) is a well-known product with anti-inflammatory and antioxidant properties. The current study aimed to investigate the impacts of WGO against ethanol-induced liver and kidney dysfunction at the serum, anti-inflammatory, antioxidants and anti-apoptotic signaling pathways. Rats received saline orally as a negative control or WGO in a dose of 1.5 mL/kg (1400 mg/kg body weight orally) for 15 days. The affected group received ethanol 50% v/v 10 mL/kg (5 g/kg) body weight orally once a day for consecutive 15 days to induce hepatorenal injuries in ethanolic non-treated group. The protective group received WGO daily 1 h before ethanol administration. Serum (1.5 mL) from blood was extracted and examined for the changes in biochemical assessments in serum alkaline phosphatase (ALP), alanine aminotransferase (ALT), bilirubin, serum γ-glutamyl transpeptidase (GGT), total protein, serum albumin, butyrylcholinesterase (BChE), total cholesterol (TC), total triglyceride (TG), urea, creatinine, uric acid, potassium (K⁺), Beta-2 microglobulin (β₂M), malondialdehyde (MDA), catalase (CAT), reduced glutathione (GSH), superoxide dismutase (SOD) and aspartate aminotransferase (AST). Kidney and liver homogenate was used to measure MDA, GSH and catalase activities. Quantitative real time PCR (qRT-PCR) was used to express Nrf2 and HO-1 in liver, and NF-kB and kidney injury molecule (KIM-1) in kidneys, which are correlated with oxidative stress and inflammation. Capase-3 and Bcl2 genes were examined using immunohistochemical analysis in the kidney and liver. Ethanol administration induced significant alteration in examined liver and kidney markers (AST, ALT, GGT, ALP, total proteins, urea, creatinine and uric acid). Moreover, alcohol administration decreased antioxidant activities at serum and hepatorenal tissues (GSH, catalase and SOD), while MDA was increased as a tissue degradation marker. Inflammatory cytokines, together with genes of oxidative stress markers (Nrf2 and HO-1), were all affected. At cellular levels, apoptotic marker caspase-3 was upregulated, while antiapoptotic marker B-cell lymphoma 2 (Bcl2), was down regulated using immunohistochemical analysis. Of interest, pretreatment with WGO improved the side effects induced by ethanol on hepatic, renal biomarkers and reversed its impact on serum and tissue antioxidant parameters. Nrf2/HO-1 were upregulated, while NFk-B and KIM-1 were downregulated using real time PCR. Immune reactivities of caspase-3 and Bcl2 genes were restored in the protective group. In conclusion, WGO ameliorated ethanol-induced hepatic and renal dysfunction at the biochemical, molecular and cellular levels by regulating some mechanisms that controls oxidative stress, apoptosis, inflammation and anti-apoptotic pathways.

Protective Effect of Vitamin E on Cadmium-Induced Renal Oxidative Damage and Apoptosis in Rats

Cadmium (Cd), a widely distributed heavy metal, is extremely toxic to the kidney. Vitamin E (VE) is an important antioxidant in the body. It is known that VE exerts a protective effect on renal oxidative damage caused by Cd, but the effect and mechanism of VE on apoptosis are not fully understood. Thus, we conducted this study to explore the protective effect of VE on Cd-induced renal apoptosis and to elucidate its potential mechanism. Thirty-two 9-week-old male Sprague-Dawley rats were randomly divided into four groups, namely control, VE (100 mg/kg VE), Cd (5 mg/kg CdCl₂), and VE + Cd (100 mg/kg VE + 5 mg/kg CdCl₂), and received intragastric administration of Cd and/or VE for 4 weeks. The results showed that Cd exposure significantly reduced the weight of the body and kidney, elevated the accumulation of Cd in the kidney as well as the levels of BUN and Scr in serum, caused renal histological alterations, decreased the GSH and T-AOC contents and antioxidant enzyme (SOD, CAT, GSH-PX) activities, and increased renal MDA content. And the increased number of TUNEL-positive cells by Cd was accompanied by upregulated mRNA and protein expressions of apoptotic regulatory molecules (Bax, Caspase-3, GRP94, GRP78, Caspase-8) and downregulated Bcl-2 expressions. However, the combined treatment of Cd and VE could restore the above parameters to be close to those in the control rats. In conclusion, VE supplement could alleviate Cd-induced rat renal damage and oxidative stress through enhancing the antioxidant defense system and inhibiting apoptosis of renal cells.

Picroside II Improves Severe Acute Pancreatitis-Induced Hepatocellular Injury in Rats by Affecting JAK2/STAT3 Phosphorylation Signaling

Picroside II is an important ingredient agent in Traditional Chinese medicine and hoped to reduce hepatocellular injury caused by severe acute pancreatitis (SAP). An SAP-induced hepatocellular injury model was established in rats by using pentobarbital sodium. 27 rats were divided into 3 groups: the sham group (SG), model group (MG), and Picroside groups (PG). SAP-induced hepatocellular injury was assessed using hematoxylin and eosin staining. We measured hepatocellular enzymes (amylase (AMY), alanine aminotransferase (ALT), and aspartate aminotransferase (AST)), oxidative stress factors (superoxidase dismutase (SOD) and malondialdehyde (MDA)), and inflammatory factors (tumor necrosis factor α (TNF-α), interleukin- (IL-) 6, and IL-10), apoptotic factors (BAX and cleaved caspase 3), and inflammatory signaling (Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3), p-JAK2, and p-STAT3) in hepatocellular tissues. The SAP-induced hepatocellular injury model was successfully established. Picroside II treatment repaired hepatocellular injury by reducing the activities of AMY, ALT, and AST; reducing the levels of MDA, TNF-α, IL-1, IL-6, p-JAK2, p-STAT3, BAX, and cleaved caspase 3; and increasing the levels of SOD and IL-10. Picroside II exerted protective function for the SAP-induced hepatocellular injury model. Picroside II improved SAP-induced hepatocellular injury and antioxidant and anti-inflammatory properties by affecting JAK2/STAT3 phosphorylation signaling.

Grape Seed Proanthocyanidin Extract Mitigates Titanium Dioxide Nanoparticle (TiO2-NPs)-Induced Hepatotoxicity Through TLR-4/NF-κB Signaling Pathway

With the progress of nanotechnology, the adverse effects of nanoscale materials are receiving much attention. Inhibition of toll-like receptor 4 (TLR-4)/nuclear factor kappa B (NF-κB) signaling is a hallmark for downregulating the expression of many inflammatory genes implicated in oxidative stress. Therefore, the present study aimed to demonstrate the influence of grape seed proanthocyanidin extract (GSE) on the hepatic TLR-4/ NF-κB signaling pathway in TiO₂-NP-induced liver damage in rats. Forty male Albino rats were divided into 4 groups (n = 10): G1 was used as a control, G2 received TiO₂-NPs (500 mg/kg/day orally) from the 17th to 30th day (acute toxicity), G3 received GSE (75 mg/kg/day orally) for 30 days, and G4 pre- and co-treated with GSE (for 30 days) and TiO₂-NPs (from the 17th to 30th day), with the aforementioned doses. TiO₂-NPs induced severe hepatic injury that was indicated by biochemical alterations in serum liver markers (acetylcholinesterase, ALT, ALP, total proteins, albumin, and direct bilirubin), oxidative stress indicators (MDA, GSH, and catalase), and histopathological alterations as well. Moreover, TiO₂-NPs triggered an inflammatory response via the upregulation of TLR-4, NF-κB, NIK, and TNF-α mRNA expressions. Pre- and co-treatments with GSE alleviated the detrimental effects of TiO₂-NPs which were enforced by the histopathological improvements. These results indicated that GSE effectively protected against TiO₂-NP-induced hepatotoxicity via the inhibition of TLR-4/NF-κB signaling and hence suppressed the production of pro inflammatory cytokines such as TNF-α and improved the antioxidant status of the rats.

Melatonin and vitamin E alleviate homocysteine-induced oxidative injury and apoptosis in endothelial cells

A relationship exists between hyperhomocysteinemia and cardiovascular diseases, although the underlying mechanisms are still incompletely defined. One possibility involves a homocysteine (Hcy)-induced increased oxidative stress. Melatonin (Mel) and vitamin E (vitE) are important anti-oxidants. The main purpose of this study was (1) to compare the effect of treatments with Mel, vitE or both, on Hcy-induced apoptosis in human umbilical vein endothelial cells (HUVECs), and (2) to investigate the underlying mechanisms. Cell proliferation assay was carried out by Water Soluble Tetrazolium-1 (WST-1) assay kit. Apoptotic index was calculated by TUNEL Assay. Anti-oxidant parameters were studied by measurement of reactive oxygen species (ROS) and lipid peroxidation (LPO) levels. mRNA and protein expression levels of apoptotic and anti-apoptotic genes and proteins were studied by quantitative real time polymerase chain reaction (qRT-PCR) and Western blotting experiments respectively. The results showed that treatments with Mel, vitE or Mel + vitE suppressed Hcy-induced cell death, with a higher efficiency for the Mel and Mel + vitE treatments. Our results suggests that the mechanisms by which these anti-oxidants protected endothelial cells include the decrease in ROS and LPO levels, an increase in cell migration, the downregulation of pro-apoptotic proteins Cas 3, Cas 9, Cyt C and Bax and the upregulation of anti-apoptotic protein Bcl 2. Collectively, these results revealed the protective role of vitE and Mel against Hcy-induced cell apoptosis, which may add insight into therapeutic approaches to Hcy-induced damages.

Vitamin E preconditioning alleviates in vitro thermal stress in cultured human epidermal keratinocytes

AIMS

Thermal burns are the most common type of skin injuries. Clinically, the deteriorating thermal wounds have been successfully treated with skin cell sheets, suspensions or bioengineered skin substitutes. After thermal injury, oxidative microenvironment prevalent in the burnt tissue due to imbalance between production of free radicals and antioxidants defense aiding to destruction of cellular or tissue components. However, depleted antioxidant content particularly vitamin E after heat injury challenges efficient regenerative and healing capacity of transplanted cells. Thus, aim of current study was to pretreat human epidermal keratinocytes with vitamin E in order to enhance their survival rate and therapeutic ability under oxidative microenvironment induced by in vitro heat stress.

MAIN METHODS

Keratinocytes were treated with 100 μM vitamin E at 37 °C for 24 h followed by thermal stress at 51 °C for 10 min. Cell viability and cytotoxicity assays, gene expression analysis and paracrine release analysis were performed.

KEY FINDINGS

Vitamin E preconditioning resulted in significantly improved cell morphology, enhanced viability and reduced lactate dehydrogenase release. Furthermore, Vitamin E preconditioned cells exposed to thermal stress showed significant down-regulated expression of BAX and up-regulated expression of PCNA, BCL-XL, vascular endothelial growth factor (VEGF), involucrin, transglutaminase 1 (TGM1) and filaggrin (FLG) escorted by increased paracrine release of VEGF, basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF).

SIGNIFICANCE

Results of the current study suggest that clinical transplantation of vitamin E preconditioned keratinocytes alone or in combination with dermal fibroblasts in skin substitutes for the treatment of thermally injured skin.