Anti-apoptotic and Anti-inflammatory Effects of Olive Leaf Extract Against Cisplatin-induced Nephrotoxicity in Male Rats

Antioxidant and anti-inflammatory activity by modulating IL-6 as a potential mechanism in the nephroprotective and hepatoprotective properties of Tribulus terrestris

Background and purpose

Carboplatin, a second-generation platinum-containing compound is associated with renal tubular injury and hepatic damage in cancer patients. Tribulus terrestris (TT) is widely used in Indian traditional medicine for its anti-inflammatory properties. The present study aimed to evaluate TT's beneficial effects against liver and kidney damage induced by carboplatin.

Experimental approach

An in-vivo study was conducted on thirty rats. All the groups, except the control, received intraperitoneal carboplatin 90 mg/kg on day 5; the three treatment groups received TT extract (1 g/kg, 1.25, and 1.5 g/kg) for 14 days. Serum and tissue parameters for liver functions, kidney functions, oxidative stress, and inflammatory marker interleukin 6 were measured along with histopathological assessment.

Findings/Results

TT at 1.5 g/kg on day 14 significantly reduced creatinine and aspartate transaminase levels compared to the carboplatin group. The increase in malondialdehyde levels and decrease in glutathione levels was significantly reversed in the groups treated with TT 1.25 and 1.5 g/kg. Interleukin 6 showed a significant decrease in treatment groups when compared to the carboplatin group. Carboplatin distorted hepatic architecture and caused diffused inflammatory cell infiltration in the peritubular interstitial spaces in the kidney. The histopathological evaluation confirmed that TT extract ameliorated hepatic and kidney damage by restoring to normal architecture.

Conclusion and implications

Aqueous extract of TT demonstrated a therapeutic effect against nephrotoxicity and hepatotoxicity caused by carboplatin. The observed benefits can be attributed to its anti-inflammatory action and antioxidant properties.

Radioprotective Effects of Carvacrol and/or Thymol against Gamma Irradiation-Induced Acute Nephropathy: In Silico and In Vivo Evidence of the Involvement of Insulin-like Growth Factor-1 (IGF-1) and Calcitonin Gene-Related Peptide

Radiotherapy (RT) is an effective curative cancer treatment. However, RT can seriously damage kidney tissues resulting in radiotherapy nephropathy (RN) where oxidative stress, inflammation, and apoptosis are among the common pathomechanisms. Carvacrol and thymol are known for their antioxidative, anti-inflammatory, and radioprotective activities. Therefore, this study investigated the nephroprotective potentials of carvacrol and/or thymol against gamma (γ) irradiation-induced nephrotoxicity in rats along with the nephroprotection mechanisms, particularly the involvement of insulin-like growth factor-1 (IGF-1) and calcitonin gene-related peptide (CGRP). Methods: Male rats were injected with carvacrol and/or thymol (80 and 50 mg/kg BW in the vehicle, respectively) for five days and exposed to a single dose of irradiation (6 Gy). Then, nephrotoxicity indices, oxidative stress, inflammatory, apoptotic biomarkers, and the histopathological examination were assessed. Also, IGF-1 and CGRP renal expressions were measured. Results: Carvacrol and/or thymol protected kidneys against γ-irradiation-induced acute RN which might be attributed to their antioxidative, anti-inflammatory, and antiapoptotic activities. Moreover, both reserved the γ -irradiation-induced downregulation of CGRP- TNF-α loop in acute RN that might be involved in the pathomechanisms of acute RN. Additionally, in Silico molecular docking simulation of carvacrol and thymol demonstrated promising fitting and binding with CGRP, IGF-1, TNF-α and NF-κB through the formation of hydrogen, hydrophobic and alkyl bonds with binding sites of target proteins which supports the reno-protective properties of carvacrol and thymol. Collectively, our findings open a new avenue for using carvacrol and/or thymol to improve the therapeutic index of γ-irradiation.

TLR4/Inflammasomes Cross-Talk and Pyroptosis Contribute to N-Acetyl Cysteine and Chlorogenic Acid Protection against Cisplatin-Induced Nephrotoxicity

BACKGROUND

Cisplatin (Cp) is an antineoplastic agent with a dose-limiting nephrotoxicity. Cp-induced nephrotoxicity is characterized by the interplay of oxidative stress, inflammation, and apoptosis. Toll-4 receptors (TLR4) and NLPR3 inflammasome are pattern-recognition receptors responsible for activating inflammatory responses and are assigned to play a significant role with gasdermin (GSDMD) in acute kidney injuries. N-acetylcysteine (NAC) and chlorogenic acid (CGA) have documented nephroprotective effects by suppressing oxidative and inflammatory pathways. Therefore, the current study aimed to investigate the contribution of the upregulation of TLR4/inflammasomes/gasdermin signaling to Cp-induced nephrotoxicity and their modulation by NAC or CGA.

METHODS

A single injection of Cp (7 mg/kg, i.p.) was given to Wistar rats. Rats received either NAC (250 mg/kg, p.o.) and/or CGA (20 mg/kg, p.o.) one week before and after the Cp injection.

RESULTS

Cp-induced acute nephrotoxicity was evident by the increased blood urea nitrogen and serum creatinine and histopathological insults. Additionally, nephrotoxicity was associated with increased lipid peroxidation, reduced antioxidants, and elevated levels of inflammatory markers (NF-κB and TNF-α) in the kidney tissues. Moreover, Cp upregulated both TLR4/NLPR3/interleukin-1beta (IL-1β) and caspase-1/GSDMD-signaling pathways, accompanied by an increased Bax/BCL-2 ratio, indicating an inflammatory-mediated apoptosis. Both NAC and/or CGA significantly corrected these changes.

CONCLUSIONS

This study emphasizes that inhibition of TLR4/NLPR3/IL-1β/GSDMD might be a novel mechanism of the nephroprotective effects of NAC or CGA against Cp-induced nephrotoxicity in rats.

Approaches in Hydroxytyrosol Supplementation on Epithelial-Mesenchymal Transition in TGFβ1-Induced Human Respiratory Epithelial Cells

Hydroxytyrosol (HT) is an olive polyphenol with anti-inflammatory and antioxidant properties. This study aimed to investigate the effect of HT treatment on epithelial-mesenchymal transition (EMT) in primary human respiratory epithelial cells (RECs) isolated from human nasal turbinate. HT dose-response study and growth kinetic study on RECs was performed. Several approaches on HT treatment and TGFβ1 induction with varying durations and methods was studied. RECs morphology and migration ability were evaluated. Vimentin and E-cadherin immunofluorescence staining and Western blotting [E-cadherin, vimentin, SNAIL/SLUG, AKT, phosphorylated (p)AKT, SMAD2/3 and pSMAD2/3] were performed after 72-h treatment. In silico analysis (molecular docking) of HT was performed to evaluate the potential of HT to bind with the TGFβ receptor. The viability of the HT-treated RECs was concentration-dependent, where the median effective concentration (EC₅₀) was 19.04 μg/mL. Testing of the effects of 1 and 10 µg/mL HT revealed that HT suppressed expression of the protein markers vimentin and SNAIL/SLUG while preserving E-cadherin protein expression. Supplementation with HT protected against SMAD and AKT pathway activation in the TGFβ1-induced RECs. Furthermore, HT demonstrated the potential to bind with ALK5 (a TGFβ receptor component) in comparison to oleuropein. TGFβ1-induced EMT in RECs and HT exerted a positive effect in modulating the effects of EMT.

Bone-Marrow-Derived Mesenchymal Stem Cells, Their Conditioned Media, and Olive Leaf Extract Protect against Cisplatin-Induced Toxicity by Alleviating Oxidative Stress, Inflammation, and Apoptosis in Rats

BACKGROUND

Hepatic and renal damage is a cisplatin (Cis)-induced deleterious effect that is a major limiting factor in clinical chemotherapy.

OBJECTIVES

The current study was designed to investigate the influence of pretreatment with olive leaf extract (OLE), bone-marrow-derived mesenchymal stem cells (BM-MSC), and their conditioned media (CM-MSC) against genotoxicity, nephrotoxicity, hepatotoxicity, and immunotoxicity induced by cisplatin in rats.

METHODS

The rats were randomly divided into six groups (six rats each) as follows: Control; OLE group, treated with OLE; Cis group, treated with a single intraperitoneal dose of Cis (7 mg/kg bw); Cis + OLE group, treated with OLE and cisplatin; Cis + CM-MSC group, treated with BM-MSC conditioned media and Cis; and Cis + MSC group, treated with BM-MSC in addition to Cis.

RESULTS

Cis resulted in a significant deterioration in hepatic and renal functions and histological structures. Furthermore, it increased inflammatory markers (TNF-α, IL-6, and IL-1β) and malondialdehyde (MDA) levels and decreased glutathione (GSH) content, total antioxidant capacity (TAC), catalase (CAT), and superoxide dismutase (SOD) activity in hepatic and renal tissues. Furthermore, apoptosis was evident in rat tissues. A significant increase in serum 8-hydroxy-2-deoxyguanosine (8-OH-dG), nitric oxide (NO) and lactate dehydrogenase (LDH), and a decrease in lysozyme activity were detected in Cis-treated rats. OLE, CM-MSC, and BM-MSC have significantly ameliorated Cis-induced deterioration in hepatic and renal structure and function and improved oxidative stress and inflammatory markers, with preference to BM-MSC. Moreover, apoptosis was significantly inhibited, evident from the decreased expression of Bax and caspase-3 genes and upregulation of Bcl-2 proteins in protective groups as compared to Cis group.

CONCLUSIONS

These findings indicate that BM-MSC, CM-MSC, and OLE have beneficial effects in ameliorating cisplatin-induced oxidative stress, inflammation, and apoptosis in the hepatotoxicity, nephrotoxicity, immunotoxicity, and genotoxicity in a rat model.

Antioxidant, anti-inflammatory, and anti-fibrotic properties of olive leaf extract protect against L-arginine induced chronic pancreatitis in the adult male albino rat

Chronic pancreatitis (CP) is an inflammatory disease affects the pancreas with upcoming fibrosis and notable parenchymal destruction. CP poses a high risk for pancreatic carcinoma. The present study aimed to investigate, for the first time up to our knowledge, the effect of olive leaf extract on L-arginine induced CP with referral to some of its underlying mechanisms. Forty adult male albino rats were divided equally into four groups; control, olive leaf extract treated (200 mg/kg orally once daily), CP group (300 mg L-arginine/100 g body weight intraperitoneally, once daily for 3 weeks then every 3 days for the subsequent 3 weeks), and CP treated with olive leaf extract group. At the end of the experiment, body weight, serum glucose, serum insulin, homeostatic model assessment of insulin resistance (HOMA-IR), serum amylase and lipase as well as tissue superoxide dismutase (SOD), and malondialdehyde (MDA) levels were assessed. Pancreatic tissues were subjected to histological and immuno-histochemical studies. The CP group revealed significant decrease in body weight and increase in serum glucose, serum insulin, HOMA-IR score, serum amylase, and serum lipase levels. Significant increase in MDA level and decrease in SOD level were detected. Marked degenerative changes and fibrosis were detected. Upregulation of alpha smooth muscle actin (α-SMA), transforming growth factor beta (TGF-β), caspase-3, and interleukin-6 (IL-6) immunoreactions were implicated in CP pathogenesis. Olive leaf extract alleviated all the examined parameters via its-antioxidant, anti-inflammatory, and anti-fibrotic properties. Olive leaf extract can protect against CP and restore pancreatic functions.

Pro-Angiogenic Effects of Natural Antioxidants Extracted from Mango Leaf, Olive Leaf and Red Grape Pomace over Endothelial Colony-Forming Cells

Cardiovascular diseases remain the leading cause of death worldwide, mainly triggered by the formation of atherosclerotic plaques that reduce blood flow. Angiogenic cell therapy based on endothelial colony forming cells (ECFCs) constitutes a promising alternative to promote vascular revascularization; however, under the oxidative environment that prevails in ischemic areas, these cells become impaired. Thus, it is necessary to investigate strategies to enhance their regenerative properties. Antioxidant substances, such as polyphenols, have been shown to be useful for this purpose. In the current study we evaluated the potential of mango leaves, olive leaves and red grape pomace extracts, rich in polyphenols, to promote ECFC reparative effects. For this, aqueous and ethanolic extracts of the aforementioned raw materials were obtained by pressurized liquid extraction (PLE). After evaluating the polyphenol content and the antioxidant activity, in vitro assays were carried out, and we found that ethanolic extracts at low concentrations improved angiogenic capacities of ECFCs and reduced proliferation, apoptosis, and the inflammatory response of these cells. Overall, mango leaves ethanolic extract provided the most promising results, but all three extracts ameliorated the functionality of ECFCs.

Preparation of highly purified oleuropein by combinative technology off line of HSCCC-PHPLC based on dual wavelength

Oleuropein is the main active substance in foods or functional foods produced from olive (Olea europaea L.) leaves. In the present study, the combinative technology off line of HSCCC-PHPLC based on dual wavelength was used to separate highly purified oleuropein from oleuropein extract. Response surface methodology was used to optimize the conditions of HSCCC. Furthermore, a large amount of higher purified oleuropein was obtained through HSCCC at the wavelength of 254 nm, and oleuropein with the purity greater than 98.5% was obtained by PHPLC at the wavelength of 300 nm. Finally, the purity and structure identification of highly purified oleuropein were determined by various methods and its stability was investigated. As a result, oleuropein was stable in solution, and had good stability under the condition of dark storage at 4°C within a week or under the condition of dark storage at -20°C within one year. PRACTICAL APPLICATION: In this study, an efficient method for purification and refining of oleuropein by combinative technology off line of HSCCC-PHPLC based on dual wavelength was established. Oleuropein with the purity greater than 98.5% was macro-obtained via the technology. The highly purified oleuropein could be used to control the quality of olive products.

Olive oil and leaf extract prevent fluoxetine-induced hepatotoxicity by attenuating oxidative stress, inflammation and apoptosis

Olive oil and leaf extract have several health benefits; however, their beneficial effect against fluoxetine-induced liver injury has not been investigated. The present study aimed to scrutinize the impact of fluoxetine on the liver of rats and to evaluate the protective effects of olive oil and leaf extract. Rats received fluoxetine orally at dose of 10 mg/kg body weight for 7 consecutive days. The fluoxetine-induced rats were concurrently treated with olive oil or leaf extract. At the end of the experiment, blood and liver samples were collected for analysis. Fluoxetine administration significantly increased circulating ALT, AST, ALP and the pro-inflammatory cytokines TNF-α and IL-1β levels in rats. Histological analysis showed several alterations, such as inflammatory cells infiltration, hepatocyte vacuolation and dilated sinusoids in the liver of fluoxetine-induced rats. Concurrent supplementation of olive oil and olive leaf extract significantly reduced circulating liver function marker enzymes and pro-inflammatory cytokines, and prevented fluoxetine-induced histological alterations. Both olive oil and leaf extract significantly decreased liver lipid peroxidation and nitric oxide, and ameliorated liver glutathione, superoxide dismutase, catalase and glutathione peroxidase. In addition, olive oil and leaf extract prevented fluoxetine-induced apoptosis in the liver of rats as evidenced by decreased expression of Bax and caspase-3, and up-regulated expression of Bcl-2. In conclusion, olive oil and leaf extract protect against fluoxetine-induced liver injury in rats through attenuation of oxidative stress, inflammation and apoptosis.