Effect of antioxidants, resveratrol, quercetin, and N-acetylcysteine, on the functions of cultured rat hepatic stellate cells and Kupffer cells

Quercetin and L-Arginine Ameliorated the Deleterious Effects of Copper Oxide Nanoparticles on the Liver of Mice Through Anti-inflammatory and Anti-apoptotic Pathways

The widespread use and applications of copper oxide nanoparticles (CuO NPs) in daily life make human exposure to these particles inevitable. This study was carried out to investigate the deteriorations in hepatic and serum biochemical parameters induced by CuO NPs in adult male mice and the potential ameliorative effect of L-arginine and quercetin, either alone or in combination. Seventy adult male mice were equally allocated into seven groups: untreated group, L-arginine, quercetin, CuO NPs, arginine + CuO NPs, quercetin + CuO NPs, and quercetin + arginine + CuO NPs. Treating mice with CuO NPs resulted in bioaccumulation of copper in the liver and consequent liver injury as typified by elevation of serum ALT activity, reduction in the synthetic ability of the liver indicated by a decrease in the hepatic arginase activity, and serum total protein content. This copper accumulation increased oxidative stress, lipid peroxidation, inflammation, and apoptosis as manifested by elevation in malondialdehyde, nitric oxide, tumor necrosis factor-α, the expression level of caspase-3 and bax quantified by qPCR, and the activity of caspase-3, in addition to the reduction of superoxide dismutase activity. It also resulted in severe DNA fragmentation as assessed by Comet assay and significant pathological changes in the liver architecture. The study proved the efficiency of quercetin and L-arginine in mitigating CuO NPs-induced sub-chronic liver toxicity due to their antioxidant, anti-inflammatory, and anti-apoptotic properties; ability to inhibit DNA damage; and the potential as good metal chelators. The results of histopathological analysis confirmed the biochemical and molecular studies.

Phytochemicals in Cancer Treatment and Cancer Prevention-Review on Epidemiological Data and Clinical Trials

Phytochemicals are a non-nutritive substances that are present in plants and contribute significantly to their flavor and color. These biologically active compounds are classified into five major groups, namely phenolics, carotenoids, organosulfur compounds, nitrogen-containing compounds, and alkaloids, and are known for their potential health benefits in the prevention of various diseases, including cancer. The purpose of this review article is to explore the potential therapeutic benefits of the dietary phytochemicals, such as flavonoids, phenolic acids, phytosterols, carotenoids, and stilbenes, in cancer treatment and prevention based on the epidemiological studies and clinical trials. Although the majority of epidemiological studies report a significant advantage of the heightened phytochemical consumption and increased serum levels of these compounds, linking increased exposure with a lower cancer risk across most cancer types, these effects could not be replicated in the most available clinical trials. In fact, many of these trials were withdrawn early due to a lack of evidence and/or risk of harm. Despite the strong anticancer effect of phytochemicals, as well as their proven efficacy in multiple epidemiological studies, there is still a great need for human studies and clinical trials, with great caution regarding the safety measures. This review article provides an overview of the epidemiological and clinical evidence supporting the potential chemopreventive and anticancer properties of phytochemicals, with a focus on the need for further research in this area.

Interaction of quercetin and 5-fluorouracil: cellular and pharmacokinetic study

5-fluorouracil (5-FU) is a widely used chemotherapeutic agent, and its uncontrolled blood levels contribute to toxicity. Quercetin, as an important flavonoid, has many biological effects, including anti-tumor and anti-inflammatory features. The current study investigated the synergistic effect between 5-FU and quercetin using HT-29 cell line and fibroblast cells. Rats were assigned to two groups. The 5-FU/quercetin group received intraperitoneal quercetin (10 mg/kg) and the Tween was injected to the control group for 14 consecutive days. On the 15th day, both groups received 50 mg/kg of 5-FU. Upon the final injection, blood samples were obtained at different times. Pharmacokinetic parameters were evaluated using high-performance liquid chromatography (HPLC). The mean (±SD) of maximum plasma concentration (C_max) of 5-FU in combination therapy group was 3.10 ± 0.18 μg/ml and the area under the curve (AUC) was 153.89 ± 21.36, which increased by 113% and 128% compared to control group, respectively. Quercetin increased anti-tumor activity of 5-FU and enhanced C_max and AUC of 5-FU. These findings confirm the synergistic effects between quercetin and 5-FU at the usual doses in cancer treatment, which may lead to reduced toxicity.

Moringa oleifera: An Updated Comprehensive Review of Its Pharmacological Activities, Ethnomedicinal, Phytopharmaceutical Formulation, Clinical, Phytochemical, and Toxicological Aspects

Moringa oleifera, also known as the "tree of life" or "miracle tree," is classified as an important herbal plant due to its immense medicinal and non-medicinal benefits. Traditionally, the plant is used to cure wounds, pain, ulcers, liver disease, heart disease, cancer, and inflammation. This review aims to compile an analysis of worldwide research, pharmacological activities, phytochemical, toxicological, and ethnomedicinal updates of Moringa oleifera and also provide insight into its commercial and phytopharmaceutical applications with a motive to help further research. The scientific information on this plant was obtained from various sites and search engines such as Scopus, Pub Med, Science Direct, BMC, Google Scholar, and other scientific databases. Articles available in the English language have only been referred for review. The pharmacological studies confirm the hepatoprotective, cardioprotective, and anti-inflammatory potential of the extracts from the various plant parts. It was found that bioactive constituents are present in every part of the plant. So far, more than one hundred compounds from different parts of Moringa oleifera have been characterized, including alkaloids, flavonoids, anthraquinones, vitamins, glycosides, and terpenes. In addition, novel isolates such as muramoside A&B and niazimin A&B have been identified in the plant and have potent antioxidant, anticancer, antihypertensive, hepatoprotective, and nutritional effects. The traditional and nontraditional use of Moringa, its pharmacological effects and their phytopharmaceutical formulations, clinical studies, toxicity profile, and various other uses are recognized in the present review. However, several traditional uses have yet to be scientifically explored. Therefore, further studies are proposed to explore the mechanistic approach of the plant to identify and isolate active or synergistic compounds behind its therapeutic potential.

Gastroprotective and gastric healing effects of the aqueous extract of Casearia sylvestris in rodents: Ultrasound, histological and biochemical analyzes

ETHNOPHARMACOLOGICAL IMPORTANCE

Casearia sylvestris Sw. (Salicaceae) is a native plant from the Americas, where it is also known as "guaçatonga" or "erva-de-bugre." Although its leaves have been commonly used to treat inflammation and gastrointestinal disorders in South America, the antiulcer effects of an aqueous extract from this medicinal plant, similar to popular use, have not to be investigated yet.

AIM OF THE STUDY

This study evaluated the hypothesis that the aqueous extract a of C. sylvestris (AEC) prevents the gastric ulcers and accelerates the healing of ulcers already installed, by assessing ultrasound imaging, histological and biochemical analyses.

MATERIALS AND METHODS

Rats (females) were treated with AEC (3, 30 or 300 mg/kg) prior to the ethanol or piroxicam-induced gastric ulcers. The healing effect of AEC (300 mg/kg) was examined in 80% acetic acid-induced ulcer in rats, whereas the quality of healing was evaluated in recurrent 10% acetic acid-induced ulcer in mice with recurrence induced by interleukin 1β. To assess the responses of the lesions, in addition to the classical methods used to analyze gastroprotection (ex vivo), we also measured the gastric wall thickness (in vivo) using ultrasonography. After euthanasia, the extent of ulcer was determined and the levels of reduced glutathione (GSH), lipid hydroperoxides (LOOH), nitrate, and the activities of myeloperoxidase (MPO), N-acetyl-β-D-glycosaminidase (NAG), superoxide dismutase (SOD), and glutathione S-transferase (GST) were measured. The antisecretory activity of AEC was also examined based on pylorus ligated rats. Furthermore, gastric tissue samples were analyzed histologically, and phytochemical analyses of the C. sylvestris extract were parallelly performed.

RESULTS

The AEC (30 or 300 mg/kg) prevented ulcers in the ethanol- and piroxicam-induced acute. Moreover, the AEC at a dose of 300 mg/kg also accelerated the gastric healing of acetic acid-induced ulcer in rats by 48% and the ultrasonography records shown a decrease in the wall thickness and the extent of edema of ulcerous lesions promoted by the extract. The gastric healing effect of AEC was also accompanied by reduced MPO and NAG activities at acetic acid-induced ulcer in rats; as well as was by the reduction in the nitrate and LOOH levels, the increase in mucin and SOD activity, and by a partial recovery of GSH levels. The AEC (300 mg/kg) minimized the ulcer recurrence in mice exposed to IL-1β, but the extract administration did not change pH or peptic activity of gastric juice in pylorus ligated rats.

CONCLUSION

The results of this study provide convincing evidence for the therapeutic efficacy of C. sylvestris with respect to gastroprotection and indicate that ultrasound examination would be a potentially promising approach for evaluating gastroprotective effects in vivo. Collectively, our findings indicate that the gastric the gastroprotective and healing effects of aqueous extract C. sylvestris involve a reduction in acid secretion, promotion of the antioxidant system, reductions in the migration of neutrophils and mast cells, with a consequent lower inflammatory response, and the preservation of mucin.

Current strategies for targeted therapy of liver fibrosis

Liver fibrosis (LF) is an unfavorable event in the natural course of chronic liver diseases (CLD), therefore, early implementation and widespread use of antifibrotic therapy methods is a pressing issue in hepatology. The aim of the review was to describe current approaches to targeted therapy of LF.

PubMed database, Google Scholar search engine, Cochrane Database of Systematic Reviews, eLIBRARY.RU scientific electronic library, as well as reference lists of articles were used to search for scientific articles. The publications that corresponded to the aim of the study were selected for the period from 1998 to 2021 by the terms “liver fibrosis”, “pathogenesis”, and “treatment”. Inclusion criteria were restricted to targeted therapy of LF.

Despite the growing evidence for reversibility of LF, there are currently no effective or clinically approved regimens for its specific therapy. However, taking into account the relevance of the issue, scientific research in this area is necessary. Multiple drugs with a good safety profile have been studied, which, though intended for other purposes, can have a positive effect on LF. In addition, a number of innovative approaches that differ from pharmacotherapy inspire optimism about finding a solution to this problem. It is obvious that studies focused on well-characterized groups of patients with confirmed histologic, elastography, clinical, and radiological parameters are required. This is a challenging task, since the key point will be stratification of risk based on ethnicity, etiology, and clinical status, and very large samples will be required for a reliable assessment. Nevertheless, the solution will increase efficiency of treatment for patients with CLD, improve their prognosis and quality of life, and significantly reduce the need for liver transplantation, a demand for which remains extremely high worldwide.

Ameliorative effects of the phytochemicals in dates (Phoenix dactylifera) against the toxicological changes induced by fipronil in male albino rats

Scientific evidence has shown that fipronil induces oxidative stress and genotoxicity. Our study aimed to evaluate the potential oxidation in redox parameters and DNA, as well as determine the protective effect of date extract of increasing resistance to cellular damage. 30 Male albino rats were divided into six groups ( n = 5): 1) control group; 2) treatment group with date extract (1 g/kg B.W.); 3) treatment group with 1/20 LD50 of fipronil; 4) treatment group with 1/40 LD50 of fipronil; 5) treatment group with 1/20 LD50 of fipronil + 1 g/kg date extract; and 6) treatment group with 1/40 LD50 of fipronil + 1 g/kg dates extract. Date extract showed a high content of phenolic compounds and antioxidant properties. Fipronil increased 8-hydroxy-2-deoxyguanosine levels and lipid peroxidation by malondialdehyde but decreased the total antioxidant capacity in plasma. Moreover, glutathione, catalase, and superoxide dismutase levels in the liver and kidney decreased, along with histopathological abnormalities. Additionally, tail moment parameters of liver DNA and micronucleus frequencies in the bone marrow increased. This study showed that fipronil-induced various health hazards in vivo, whereas date extract alleviated the said toxicological effects. However, date extract failed to reduce genotoxicity.

MiR-155 Dysregulation Is Associated with the Augmentation of ROS/p53 Axis of Fibrosis in Thioacetamide-Induced Hepatotoxicity and Is Protected by Resveratrol

Liver fibrosis is a hallmark of thioacetamide (TAA) intoxications. MicroRNAs (miRs), such as miR-155, have been implied in the pathogenesis of liver disease, and regulated by the antioxidant and anti-inflammatory compound resveratrol (RES). The link between reactive oxygen species (ROS), tumour suppressor p53 (p53), and liver fibrosis-during the pathogenesis of TAA-induced liver injury-associated with miR-155 dysregulation with and without RES incorporation has not been previously studied. Therefore, one group of rats received TAA injections of 200 mg/kg; twice a week at the beginning of week 3 for 8 weeks (TAA group; or model group), whereas the protective group was pretreated daily with RES suspension (20 mg/kg; orally) for the first two weeks and subsequently sustained on receiving both RES and TAA until being sacrificed at the 10th week. Liver injuries developed in the model group were confirmed by a significant (p < 0.0001) elevation of hepatic tissue levels of miR-155, ROS, p53, and the profibrogenic biomarkers: tissue inhibitor of metalloproteinases-1 and α-smooth muscle actin, as well as collagen deposition (fibrosis). All these parameters were significantly (p ≤ 0.0234) protected by resveratrol (RES + TAA). In addition, we observed a significant (p < 0.0001) correlation between ROS/p53 axis mediated liver fibrosis and miR-155. Thus, TAA intoxication induced miR-155 imbalance and ROS/p53-mediated liver fibrosis, with resveratrol, conversely displaying beneficial hepatic pleiotropic effects for a period of 10 weeks.

Hepatic Myofibroblasts: A Heterogeneous and Redox-Modulated Cell Population in Liver Fibrogenesis

During chronic liver disease (CLD) progression, hepatic myofibroblasts (MFs) represent a unique cellular phenotype that plays a critical role in driving liver fibrogenesis and then fibrosis. Although they could originate from different cell types, MFs exhibit a rather common pattern of pro-fibrogenic phenotypic responses, which are mostly elicited or sustained both by oxidative stress and reactive oxygen species (ROS) and several mediators (including growth factors, cytokines, chemokines, and others) that often operate through the up-regulation of the intracellular generation of ROS. In the present review, we will offer an overview of the role of MFs in the fibrogenic progression of CLD from different etiologies by focusing our attention on the direct or indirect role of ROS and, more generally, oxidative stress in regulating MF-related phenotypic responses. Moreover, this review has the purpose of illustrating the real complexity of the ROS modulation during CLD progression. The reader will have to keep in mind that a number of issues are able to affect the behavior of the cells involved: a) the different concentrations of reactive species, b) the intrinsic state of the target cells, as well as c) the presence of different growth factors, cytokines, and other mediators in the extracellular microenvironment or of other cellular sources of ROS.

Association of resveratrol with the suppression of TNF-α/NF-kB/iNOS/HIF-1α axis-mediated fibrosis and systemic hypertension in thioacetamide-induced liver injury

Chronic liver injury can lead to hepatic failure and the only available method of treatment would be liver transplantation. The link between inflammation (TNF-α), nuclear factor-kappa B (NF-kB), nitrosative stress (iNOS) and hypoxia-inducible factor-1α (HIF-1α) in thioacetamide (TAA) induced liver fibrosis, and hypertension with and without the incorporation of the anti-inflammatory and antioxidant resveratrol (RES) has not been investigated before. Consequently, we injected rats with either 200 mg/kg TAA for 8 weeks starting at week 2 (model group) or pretreated them before TAA injections with RES (20 mg/kg) for 2 weeks and continued them on RES and TAA until being culled at week 10 (protective group). In the model group, we documented the induction of hepatic fibrosis and upregulation of tumor necrosis factor-α (TNF-α), NF-kB, inducible nitric oxide synthase (iNOS), HIF-1α and the profibrotic biomarkers alpha-smooth muscle actin (α-SMA) and matrix metalloproteinase-9 (MMP-9) that was significantly (p ≤ 0.0014) ameliorated by RES. RES also significantly (p ≤ 0.0232) reduced triglycerides (TG), cholesterol (CHOL), very low-density lipoprotein (vLDL-C), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure, and heart rate (HR) induction by TAA. Also, a significant (p < 0.0001) positive correlation between TNF-α/NF-kB/iNOS/HIF-1α axis-mediated fibrosis and hypertension and liver injury biomarkers was observed. These findings suggest that in the hepatotoxic compound, TAA is associated with TNF-α/NF-kB/iNOS/HIF-1α-mediated fibrosis and hypertension, whilst being inhibited by RES.

Click gold quantum dots biosynthesis with conjugation of quercetin for adenocarcinoma exertion

We developed a cost-effective and eco-friendly click biosynthesis of small molecule quercetin-gold quantum dots (QRT-AuQDs) involving quick conjugation using an ultrasonication method at ambient temperature by utilizing QRT and gold ions in the proportion of 0.1 : 1 (molar ratio). A comparatively very short amount of time (60 seconds) was required as compared to conventional procedures. The present biomimetics research relates to the isolation of bioactive QRT by the circularly spread silica gel layer technique (CSSGLT) and characterization (UV-Vis, FTIR, NMR and DSC analysis). Characterization of the synthesized QRT-AuQDs conjugated complex was carried out by UV-Vis, HR-TEM, DLS, zeta potential and X-ray diffraction. The main objective of the present work was to study the comparative anticancer activity of QRT and QRT-AuQDs on human lung cancer HOP-62 and leukemia K-562 cell lines. The results suggested that QRT-AuQDs showed potential for applications in anticancer treatment and were found to be a more cytotoxic agent in comparison to QRT, causing > 50% inhibition of cancer cells at the concentration < 10-7 M. Hence, small molecule conjugated QRT-AuQDs can be used as a promising material for biomedical, bioengineering and anti-infectives applications.

Comparative Analysis of the Antitumor Activity of Cis- and Trans-Resveratrol in Human Cancer Cells with Different p53 Status

Resveratrol, a natural plant phytoalexin, is produced in response to fungal infection or- UV irradiation. It exists as an isomeric pair with cis- and trans-conformation. Whereas multiple physiological effects of the trans-form, including a pronounced anti-tumoral activity, are nowadays elucidated, much less knowledge exists concerning the cis-isomer. In our work, we analyzed the antiproliferative and cytotoxic properties of cis-resveratrol in four different human tumor entities in direct comparison to trans-resveratrol. We used human cell lines as tumor models for hepatocellular carcinoma (HCC; HepG2, Hep3B), colon carcinoma (HCT-116, HCT-116/p53(-/-)), pancreatic carcinoma (Capan-2, MiaPaCa-2), and renal cell carcinoma (A498, SN12C). Increased cytotoxicity in all investigated tumor cells was observed for the trans-isomer. To verify possible effects of the tumor suppressor p53 on resveratrol-induced cell death, we used wild type and p53-deleted or -mutated cell lines for every tested tumor entity. Applying viability and cytotoxicity assays, we demonstrated a differential, dose-dependent sensitivity towards cis- or trans-resveratrol among the respective tumor types.

Effect of Quercetin on the Expression of NOXs and P-Smad3C in TGF-Β-Activated Hepatic Stellate Cell Line LX-2

Background: Hepatic stellate cells (HSCs) play a primary role in liver fibrogenesis. NOXs are the main origin of reactive oxygen species (ROS) in the liver. Among them, NOX1, NOX2, and NOX4 are expressed more in HSCs and are involved in the development of liver fibrosis. Quercetin, an abundant citrus flavonoid, is known to have beneficial effects on liver injury and hepatic fibrosis. Objectives: In this study, the effect of quercetin on NOX1, NOX2, and NOX4 expression and Smad3 phosphorylation induced by TGF-β in the human hepatic LX2 cell line was investigated. Methods: The cytotoxic effects of quercetin on the cells were determined by MTT assay. The cells were activated with 2 ng/mL of TGF-β for 24 h and then treated with different concentrations of Quercetin. The mRNA expression rates of NOX1, NOX2, NOX4, and phosphorylated Smad 3C (p-Smad3C) were analyzed using real-time polymerase chain reaction (PCR) and western blot assays. Results: TGF-β increased the mRNA expression of NOX1, NOX2, and NOX4 and the protein level of p-Smad3C in the LX2 cell line. Quercetin significantly decreased the mRNA expression of NOX1, NOX2, and NOX4 in the LX-2 cells. Moreover, quercetin significantly diminished the p-Smad3C level in the LX-2 cell line activated with TGF-β. Conclusions: Quercetin may be effective in improving hepatic fibrosis via the reduction of NOX1, NOX2, and NOX4 expression in activated HSCs. The main mechanism through which quercetin reduces the expression of these target genes may be related to the reduction of the p-Smad3C level.

Extraction and Identification of Two Flavonoids in Phlomoides hyoscyamoides as an Endemic Plant of Iran: The Role of Quercetin in the Activation of the Glutathione Peroxidase, the Improvement of the Hydroxyproline and Protein Oxidation in Bile Duct-Ligated Rats

BACKGROUND

Cholestatic liver disease, a serious chronic condition that develops progressive hepatic degeneration through free radicals.

OBJECTIVE

The present study was designed to extract and identify two flavonoids in Phlomoides hyoscyamoides plant, native to Iran and evaluate the role of quercetin identified on the liver injury among bile ductligated rats.

METHODS

This study was conducted on 25 male Wistar rats within three groups of sham control, mere bile duct-ligated, and bile duct-ligated with quercetin. The bile duct-ligated animals received quercetin at a dose of 50 mg/kg/day for 10 days, followed by biochemical tests, oxidative stress markers, activity of antioxidant enzymes and hematoxylin and eosin staining. Molecular docking was used to explore the interactive behavior of quercetin with glutathione peroxidase.

RESULTS

According to analyses of the obtained extract, two main active ingredients of P. hyoscyamoides were rutin and quercetin. Bile duct-ligated group showed a significant liver necrosis, a clear increase in plasma and tissue oxidative stress parameters, and a decrease in glutathione peroxidase activity as compared to sham control group. Quercetin injection in bile duct-ligated rats resulted in significant decrease in hydroxyproline, protein carbonyl and histopathologic indexes and significant increase in glutathione peroxidase activity (P-value≤0.05). Based on the molecular docking, the quercetin was able to regulate the glutathione peroxidase activity.

CONCLUSION

The quercetin acts as an enzyme inducer by renewing the glutathione peroxidase activity and inhibiting the oxidation of proteins and hence decreases the oxidative stress. These results could be a sign of confirming the positive role of quercetin in attenuating the liver damage and degeneration.

The effect of Ankaferd blood stopper on liver damage in experimental obstructive jaundice

Background/aims

To evaluate the potential protective effects of Ankaferd blood stopper (ABS) in an experimental obstructive jaundice (OJ) model.

Materials and methods

The study included 26 female rats, which were divided into 3 groups. The sham group, consisting of 10 rats, (group 1) only received solely laparotomy. In the control group, consisting of 8 rats, (group 2), ligation was applied to the biliary tract and no treatment was implemented. In the treatment group, consisting of 8 rats, (group 3), following ligation of biliary tract, 0.5 mL/day ABS was given for 10 days. Liver tissue and blood samples were taken for histopathological and biochemical examination.

Results

Compared to group 2, group 3 had higher aspartate aminotransferase (AST), total oxidant status (TOS) malondialdehyde (MDA), fluorescent oxidant products (FOP), and lower expression of albumin and total antioxidant status (TAS) (P < 0.05). In histopathological analysis, the mean scores of all histopathological parameters (fibrosis, portal inflammation, confluent necrosis, interphase activity, bile duct proliferation) have statistical significance between group 2 and group 3 (P < 005).

Conclusions

ABS has promising results in the treatment of experimental OJ because of its antioxidant and antiinflammatory properties. It may be used in clinical practice after more extensive studies about the effects of ABS on OJ.

The Role of Resveratrol in Liver Disease: A Comprehensive Review from In Vitro to Clinical Trials

Many studies have shown that resveratrol has a lot of therapeutic effects on liver disorders. Its administration can significantly increase the survival rate after liver transplantation, reduce fat deposition and ischemia-induced necrosis and apoptosis in Wistar rats. Resveratrol can provide Liver protection against chemical, cholestatic, and alcohol-mediated damage. It can improve glucose metabolism and lipid profile, reduce liver fibrosis, and steatosis. Additionally, it is capable of altering the fatty acid composition of the liver cells. Resveratrol may be a potential treatment option for the management of non-alcoholic fatty liver disease (NAFLD) due to its anti-inflammatory, antioxidant, and calorie-restricting effects. There are also studies that have evaluated the effect of resveratrol on lipid and liver enzyme profiles among patients with metabolic syndrome (MetS) and related disorders. Based on the extent of liver disease worldwide and the need to find new treatment possibilities, this review critically examines current in vitro and in vivo preclinical studies and human clinical studies related to liver protection.

Overview of Cellular Mechanisms and Signaling Pathways of Piceatannol

Stilbenoids are a group of naturally occurring phenolic compounds found in various plant species. They share a common backbone structure known as stilbene. However, differences in the nature and position of substituents have made it possible to produce many derivatives. Piceatannol [PT], a hydroxylated derivative from resveratrol, exerts various biological activities ranging from cancer prevention, cardio- protection, neuro-protection, anti-diabetic, depigmentation and so on. Although positive results were obtained in most cell culture and animal studies, the relevant cellular and molecular mechanisms of cytokines and signaling pathway about their biological effects still unclear. Thus, in the current review, we focus on the latest findings of PT on cellular biology in order to better understand the underlying therapeutic mechanisms of PT among various diseases.

Protective effects of extracts from Ephedra foeminea Forssk fruits against oxidative injury in human endothelial cells

ETHNOPHARMACOLOGICAL RELEVANCE

Ephedra foeminea is a member of the Ephedraceae family which is widespread in the eastern Mediterranean area. In Lebanon, Ephedra is a popular remedy in traditional medicine to prevent and/or counteract many stress oxidative-related diseases like inflammation and bacterial infections.

AIM OF THE STUDY

Oxidative stress leads to endothelial cell dysfunction, and is a major factor contributing to etiology of atherosclerosis and related diseases. This study aims to investigate the antioxidant and cytoprotective potential of extracts from E. foeminea fruits on human endothelial cells exposed to hydrogen peroxide (H₂O₂) to mimic in vitro vascular endothelium dysfunction.

MATERIALS AND METHODS

Different extracts of E. foeminea fruits were prepared using pure ethanol (EE), methanol/water (EMW), pure hexane (Ehex) or ethyl acetate/water (Epoly) as extraction solvents. The phenolome profile of each extract was characterized using high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS/MS). Total phenolic and flavonoid content, and radical scavenging properties of the extracts were assessed spectrophotometrically. Then, the effects on human endothelial cells HECV were evaluated.

RESULTS

Epoly extract showed the highest phenol and flavonoid content, and the highest radical scavenging capacity. On H₂O₂-insulted HECV cells Epoly was able: (i) to counteract the ROS/RNS production and lipid peroxidation; (ii) to rescue the ROS-dependent decrease in the mitochondrial membrane potential; (iii) to counteract the apoptosis induction; (iv) to restore endothelial cell viability and migration.

CONCLUSIONS

The findings indicated that the polyphenol-enriched extract Epoly from E. foeminea fruits is endowed with in vitro anti-oxidant and anti-apoptotic effects and might be used as nutraceutical for treating ROS-related endothelium dysfunction and inflammation.

Reversine and herbal Xiang-Sha-Liu-Jun-Zi decoction ameliorate thioacetamide-induced hepatic injury by regulating the RelA/NF-κB/caspase signaling pathway

This study investigated the anti-fibrotic effects of reversine and Chinese medicine Xiang–Sha–Liu–Jun–Zi decoction (XSLJZD) on thioacetamide (TAA)-induced hepatic injury. Sprague-Dawley rats were intraperitoneally administered with TAA, then injected with reversine intraperitoneally, and/or orally provided with XSLJZD. TAA resulted in liver injury with increases in the liver index and levels of serum aspartate aminotransferase (AST) and alanine aminotransferase. Reversine alleviated the liver index and AST level and improved TAA-induced pathological changes but decreased TAA-induced collagen deposition, and α-smooth muscle actin and transforming growth factor-β1 expression. Reversine also modulated the mRNA levels of inflammatory cytokines, such as RelA, interleukin (IL)-17A, IL-22, IL-1β, IL-6, NLR family pyrin domain containing 3, platelet-derived growth factor, and monocyte chemoattractant protein, and suppressed nuclear factor (NF)-κB (p65) phosphorylation and caspase 1 activation. Meanwhile, XSLJZD protected TAA-injured liver without increasing fibrosis and enhanced the regulating effect of reversine on RelA, IL-17A, IL-1β, and MCP-1 cytokines. In conclusion, reversine ameliorates liver injury and inhibits inflammation reaction by regulating NF-κB, and XSLJZD protects the liver through its synergistic effect with reversine on regulating inflammatory cytokines.

Synthesis and Biological Evaluation of 1,3,4-Oxadiazole Fused Resveratrol Derivatives as Anticancer Agents

A novel target compounds (9a-j) were design and synthesized and characterized by 1H & 13C NMR, ESI-MS spectral analysis. Further, these were tested for their anticancer activity against three human cancer cell lines such as MCF-7, MDA MB-231 (breast), A549 (Lung) and adriamycin was used as positive control. Among ten compounds, two compounds like 9b and 9j were showed a significant anticancer activity compared to control drug.

Amelioration of oxidative stress-mediated apoptosis in copper oxide nanoparticles-induced liver injury in rats by potent antioxidants

The purpose of this study is to investigate the therapeutic efficacy of individual or combined doses of dehydro-epiandrosterone (DHEA) and quercetin in ameliorating some biochemical indices in liver of CuO-NPs intoxicated-rats. CuO-NPs (50 nm) was administered as a daily oral dose 100 mg/kg for 2 weeks to rats followed by the fore-mentioned antioxidants for 1 month. We highlighted the therapeutic effect of DHEA and quercetin against CuO-NPs toxicity through monitoring the alteration of liver enzyme activity, antioxidant defense mechanism, necrosis, apoptosis, histopathological alterations, and DNA damage. The rats given CuO-NPs only showed marked significant elevation in liver enzymes, alteration in oxidant-antioxidant balance and an elevation in the hepatic inflammatory marker; tumor necrosis factor-α. Additionally, over expression of both caspase-3 and Bax proteins were detected. Whereas, Bcl2 was down regulated and DNA fragmentation was elevated. Moreover, Histopathological examination of hepatic tissue reinforced the previous biochemical results. Co-treatment with either DHEA, quercetin alone or in combination ameliorated the deviated parameters with variable degrees against CuO-NPs toxicity in rat. In conclusion, our findings suggested that the aforementioned treatments exert therapeutic effect in CuO-NPs toxicity by diminishing oxidative stress, mRNA gene expression and hepatic tissues DNA damage.

Role of cytoglobin, a novel radical scavenger, in stellate cell activation and hepatic fibrosis

Cytoglobin (Cygb), a stellate cell-specific globin, has recently drawn attention due to its association with liver fibrosis. In the livers of both humans and rodents, Cygb is expressed only in stellate cells and can be utilized as a marker to distinguish stellate cells from hepatic fibroblast-derived myofibroblasts. Loss of Cygb accelerates liver fibrosis and cancer development in mouse models of chronic liver injury including diethylnitrosamine-induced hepatocellular carcinoma, bile duct ligation-induced cholestasis, thioacetamide-induced hepatic fibrosis, and choline-deficient L-amino acid-defined diet-induced non-alcoholic steatohepatitis. This review focuses on the history of research into the role of reactive oxygen species and nitrogen species in liver fibrosis and discusses the current perception of Cygb as a novel radical scavenger with an emphasis on its role in hepatic stellate cell activation and fibrosis.

Targeting defective pulmonary innate immunity - A new therapeutic option?

Chronic pulmonary conditions now account for 1 in 15 deaths in the US and mortality is increasing. Chronic obstructive pulmonary disease (COPD) is due to become the 3rd largest cause of mortality by 2030 and mortality from other respiratory conditions such as asthma, idiopathic pulmonary fibrosis and cystic fibrosis are not reducing. There is an urgent need for novel therapies to address this problem as many of the current strategies targeting inflammation are not sufficient. The innate immune system of the lung is an important defence against invading pathogens, but in many chronic pulmonary diseases, this system mounts an inappropriate response. In COPD, macrophages are increased in number, but fail to clear pathogens correctly and become highly activated. This leads to increased damage and remodelling of the airways. In idiopathic fibrosis, there is a switch of macrophage phenotype to a cell that promotes abnormal repair. Neutrophils also display dysfunction in COPD where aberrant migratory profiles may lead to increased damage to lung tissue and emphysema; while in cystic fibrosis the proteolytic lung environment damages neutrophil receptors leading to ineffective phagocytosis and migration. Targeting the innate immune system to restore 'normal function' could have enormous benefits. Improving phagocytosis of pathogens could reduce exacerbations and hence the associated decline in lung function, and novel therapeutics such as sulforaphane appear to do this in vitro. Other natural products such as resveratrol and derivatives also have anti-inflammatory properties. Statins have traditionally been used to manage cholesterol levels in hypercholesterolaemia, however these molecules also have beneficial effects on the innate immune cells. Statins have been shown to be anti-inflammatory and restore aberrant neutrophil chemotaxis in aged cells. Other possible agents that may be efficacious are senolytics. These compounds include natural products such as quercetin which have anti-inflammatory properties but can also suppress viral replication. As viruses have been shown to suppress phagocytosis of macrophages, it is possible that these compounds could have benefit during viral exacerbations to protect this innate response. These compounds demonstrate that it is possible to address defective innate responses in the lung but a better understanding of the mechanisms driving defective innate immunity in pulmonary disease may lead to improved therapeutics.

Ameliorative effect of aqueous leaf extract of Solanum aethiopicum on phenylhydrazine-induced anaemia and toxicity in rats

Solanum aethiopicum is used in ethnomedicine for the treatment of overweight, constipation and anaemia. This study evaluated the ameliorative effect of aqueous leaf extract of S. aethiopicum on phenylhydrazine-induced anaemia in rats. Acute toxicity was determined in male and female rats (n = 5/group/sex) by oral administration of single dose of up to 5000 mg/kg of the S. aethiopicum extract. The experimental rats were randomly grouped into five (5) groups of 6 rats each. Group (i) served as normal control, group (ii) negative control, group (iii) standard drug-5 mg/kg ferrous sulphate, groups (iv) and (v), 200 and 400 mg/kg of S. aethiopicum extract respectively. Phenylhydrazine (PHZ) was administered intraperitoneally at the dose of 50 mg/kg body weight for two consecutive days to groups (ii-v). After 14 days, the rats were sacrificed; blood, liver and kidney were collected. The haematological, lipid profile, liver and kidney function parameters were determined and the histopathology of the liver and kidney were examined. In acute toxicity study, no signs of toxicity or death were recorded. The study shows an observable significant (P < 0.05) increase in packed cell volume, haemoglobin and red blood cell counts at 400 mg/kg S. aethiopicum extract in both the male and female rats when compared to other groups. Solanum aethiopicum extract at the dose of 400 mg/kg reduced aspartate aminotransferase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), urea, creatinine and chloride. The results of this study lent credence to the use of S. aethiopicum leaf as an anti-anaemic tonic with a wide margin of safety and hepato/reno-protective potentials.

A multi-scale approach to study biochemical and biophysical aspects of resveratrol on diesel exhaust particle-human primary lung cell interaction

Diesel exhaust particles (DEPs) are major air pollutants that lead to numerous human disorders, especially pulmonary diseases, partly through the induction of oxidative stress. Resveratrol is a polyphenol that ameliorates the production of reactive oxygen species (ROS) and delays aging-related processes. Herein we studied the cytoprotective effect of resveratrol on DEP-exposed human lung cells in a factorial experimental design. This work investigates biophysical features including cellular compositions and biomechanical properties, which were measured at the single-cell level using confocal Raman microspectroscopy (RM) and atomic force microscopy (AFM), respectively. Principal component analysis (PCA), hierarchical cluster analysis (HCA) and partial least square regression (PLS) analysis were applied to analyze Raman spectra with and without resveratrol protection. The health status of individual cells could be effectively predicted using an index derived from characteristic Raman spectral peak (e.g., 1006 cm⁻¹) based on PLS model. AFM measurements indicated that cellular adhesion force was greatly reduced, while Young’s modulus was highly elevated in resveratrol treated DEP-exposed cells. Anti-oxidant resveratrol reduced DEP-induced ROS production and suppressed releases of several cytokines and chemokines. These findings suggest resveratrol may enhance resistance of human lung cells (e.g., SAEC) to air pollutants (e.g. DEPs).

The effect of a Mediterranean diet on metabolic parameters in patients with non-alcoholic fatty liver disease: A systematic review of randomized controlled trials

BACKGROUND

Dietary habit can play a key role in the prevention and treatment of fatty liver disease (NAFLD). Although many studies have investigated the effect of Mediterranean diet on NAFLD, findings are inconsistent and there is no systematic review on this topic. Therefore, the aim of this systematic review is to summarize the effect of Mediterranean diet on serum metabolic indices and anthropometric measures among NAFLD patients.

METHODS

We searched titles, abstracts, and keywords of articles indexed in Science Direct, MEDLINE, and Google Scholar databases up to October 2018 to identify eligible RCT studies. Randomized clinical trials assessing the effects of MD on NAFLD were included.

RESULTS

The present study included 10 randomized controlled trials, which involved a total of 856 adults with NAFLD. According to the result, MD may improve anthropometric measures, lipid profile, glycemic indices, liver enzyme, and NAFLD severity indices among patients with NAFLD.

CONCLUSION

We found that MD could alleviate NAFLD severity parameters but differences between studies should be taken into account. Finally, in order to draw a firm link between MD and NAFLD, more clinical trials with adequate sample size and better methodology should be done.

Antifibrotic effect of methylated quercetin derivatives on TGFβ-induced hepatic stellate cells

Quercetin (QCT) and isorhamnetin (ISO), natural flavonoids, were both shown to possess antifibrotic activity in in vivo and in vitro models of hepatic fibrosis. Although ISO is a direct metabolite of QCT differing by a methyl group, it has been reported to be absorbed more adequately and eliminated slower than QCT after oral administration. Our aim of the study was to investigate biological effect of mono-methylated QCT derivatives against fibrosis using rat hepatic stellate cells (HSC-T6). All test derivatives were synthesized from QCT. HSC-T6 cells were induced by TGFβ and treated with derivatives followed by cell proliferation assay, immunofluorescence staining of αSMA, and gene expression analysis of fibrosis markers. All compounds showed a dose- and time-dependent antiproliferation effect. ISO, 3-O-methylquercetin (3MQ), and rhamnetin (RHA) reduced αSMA mRNA; 3MQ prevented the augmentation of collagen I mRNA; and compounds, except azaleatin and 3MQ, reduced Timp1 mRNA expression in TGFβ-induced HSCs. In conclusion, each compound had singular effect against different features of fibrosis depending on the position of methyl group although the further mechanism of action of compounds during fibrosis development remains to be investigated. These findings suggest that antifibrotic effect of quercetin can be enhanced by adding methyl group on functionally important position.

Natural compounds in the chemoprevention of alcoholic liver disease

Alcoholic liver disease (ALD), caused by excessive consumption of alcohol, is a major cause of chronic liver disease worldwide. Much effort has been expended to explore the pathogenesis of ALD. Hepatic cell injury, oxidative stress, inflammation, regeneration, and bacterial translocation are all involved in the pathogenesis of ALD. Immediate abstinence is the most important therapeutic treatment for affected individuals. However, the medical treatment for ALD had not advanced in a long period. Intriguingly, an increasing body of research indicates the potential of natural compounds in the targeted therapy of ALD. A plethora of dietary natural products such as flavonoids, resveratrol, saponins, and β-carotene are found to exert protective effects on ALD. This occurs through various mechanisms composed of antioxidative, anti-inflammatory, iron chelation, pro-apoptosis, and/or antiproliferation of hepatic stellate cells and hepatocellular carcinoma cells. In this review, we will summarize current knowledge about the pathogenesis and treatments of ALD and focus on the potential of natural compounds in ALD therapies and underlying mechanisms.

Dietary Flavonoids for Immunoregulation and Cancer: Food Design for Targeting Disease

Flavonoids, one of the most abundant phytochemicals in a diet rich in fruits and vegetables, have been recognized as possessing anti-proliferative, antioxidant, anti-inflammatory, and estrogenic activities. Numerous cellular and animal-based studies show that flavonoids can function as antioxidants by preventing DNA damage and scavenging reactive oxygen radicals, inhibiting formation of DNA adducts, enhancing DNA repair, interfering with chemical damage by induction of Phase II enzymes, and modifying signaling pathways. Recent evidence also shows their ability to regulate the immune system. However, findings from clinical trials have been mixed with no clear consensus on dose, frequency, or type of flavonoids best suited to elicit many of the beneficial effects. Delivery of these bioactive compounds to their biological targets through "targeted designed" food processing strategies is critical to reach effective concentration in vivo. Thus, the identification of novel approaches that optimize flavonoid bioavailability is essential for their successful clinical application. In this review, we discuss the relevance of increasing flavonoid bioavailability, by agricultural engineering and "targeted food design" in the context of the immune system and cancer.

Binding of Resveratrol to Vascular Endothelial Growth Factor Suppresses Angiogenesis by Inhibiting the Receptor Signaling

Resveratrol is a polyphenol commonly found in plants and food health products, such as grape and red wine, and was identified for its binding to vascular endothelial growth factor (VEGF) by using HerboChips screening. The binding, therefore, resulted in alterations of VEGF binding to its receptor and revealed the roles of VEGF in angiogenesis. Several lines of evidence gave support to the inhibitory activities of resveratrol in VEGF-triggered angiogenesis. In human umbilical vein endothelial cells (HUVECs), compared with a VEGF-induced group, resveratrol, at a high concentration, suppressed VEGF-mediated endothelial cell proliferation, cell migration, cell invasion, and tube formation by 80 ± 9.01%, 140 ± 3.78%, 110 ± 7.51%, and 120 ± 10.26%, respectively. Moreover, resveratrol inhibited the subintestinal vessel formation in zebrafish embryo. In signaling cascades, application of resveratrol in HUVECs reduced the VEGF-triggered VEGF receptor 2 phosphorylation and c-Jun N-terminal kinase phosphorylation. Moreover, the VEGF-mediated phosphorylations of endothelial nitric oxide synthase, protein kinase B, and extracellular signal-regulated kinase were obviously decreased by (3 ± 0.37)-, (2 ± 0.27)- and (6 ± 0.23)-fold, respectively, in the presence of resveratrol at high concentration. Parallelly, the VEGF-induced reactive oxygen species formation was significantly decreased by 50 ± 7.88% to 120 ± 14.82% under resveratrol treatment. Thus, our results provided support to the antiangiogenic roles of resveratrol, as well as its related signaling mechanisms, in attenuating the VEGF-mediated responses. The present results supported possible development of resveratrol, which should be considered as a therapeutic agent in terms of prevention and clinical treatment of diseases related to angiogenesis.

Quercetin Enhances the Thioredoxin Production of Nasal Epithelial Cells In Vitro and In Vivo

Background: Thioredoxin (TRX) acts as both a scavenger of reactive oxygen species (ROS) and an immuno-modulator. Although quercetin has been shown to favorably modify allergic rhinitis (AR) symptoms, its influence on TRX production is not well defined. The present study was designed to examine whether quercetin could favorably modify AR symptoms via the TRX production of nasal epithelial cells in vitro and in vivo. Methods: Human nasal epithelial cells (HNEpCs) were stimulated with H2O2 in the presence of quercetin. TRX levels in 24-h culture supernatants were examined with ELISA. BALB/c male mice were intraperitoneally sensitized to ovalbumin (OVA) and intranasally challenged with OVA every other day, beginning seven days after the final sensitization. The mice were orally administered quercetin once a day for five consecutive days, beginning seven days after the final sensitization. Nasal symptoms were assessed by counting the number of sneezes and nasal rubbing behaviors during a 10-min period immediately after the challenge. TRX levels in nasal lavage fluids obtained 6 h after the challenge were examined by ELISA. Results: Treatment with 1.0 nM quercetin increased H2O2-induced TRX levels. The oral administration of 20.0 mg/kg of quercetin significantly inhibited nasal symptoms after the challenge. The same dose of quercetin significantly increased TRX levels in nasal lavage fluids. Conclusions: Quercetin's ability to increase TRX production may account, at least in part, for its clinical efficacy toward AR.

Resveratrol: A miraculous natural compound for diseases treatment

Resveratrol (3, 5, 4'-trihydroxystilbene) is a nonflavonoid polyphenol that naturally occurs as phytoalexin. It is produced by plant sources such as grapes, apples, blueberries, plums, and peanut. This compound has critical roles in human health and is well known for its diverse biological activities such as antioxidant and anti-inflammatory properties. Nowadays, due to rising incidence of different diseases such as cancer and diabetes, efforts to find novel and effective disease-protective agents have led to the identification of plant-derived compounds such as resveratrol. Furthermore, several in vitro and in vivo studies have revealed the effectiveness of resveratrol in various diseases such as diabetes mellitus, cardiovascular disease, metabolic syndrome, obesity, inflammatory, neurodegenerative, and age-related diseases. This review presents an overview of currently available studies on preventive properties and essential molecular mechanisms involved in various diseases.

Suppressive Effect of Quercetin on Nitric Oxide Production from Nasal Epithelial Cells In Vitro

Nitric oxide (NO) is known to play pivotal roles as one of the final effector molecules in the development of allergic diseases, including allergic rhinitis (AR). Although quercetin has been reported to attenuate the clinical conditions of AR, its influence on NO production is not well defined. The present study aimed to examine the influence of quercetin on in vitro NO production from nasal epithelial cells after interleukin- (IL-) 4 stimulation. Human nasal epithelial cells (HNEpCs) at a concentration of 1 x 10⁵ cells/ml were stimulated with 10.0 ng/ml of IL-4 in the presence and absence of quercetin. After 48 hours, the culture supernatants were collected and assayed for NO (NO₂ and NO₃) using the Griess method. The influences of quercetin on the transcription factor, STAT6, activation, and iNOS mRNA expression were also examined using ELISA and real-time quantitative RT-PCR, respectively. Addition of quercetin to cell cultures caused suppression of NO production from HNEpCs after IL-4 stimulation. The minimum concentration of quercetin that caused significant suppression was 1.0 nM. Treatment of cells with quercetin at more than 1.0 nM suppressed STAT6 activation and iNOS mRNA expression induced by IL-4 stimulation. The present results strongly suggested that quercetin favorably modified the clinical condition of AR through the suppression of NO production from nasal epithelial cells after IL-4 stimulation.

Ameliorative effects of Moringa on cuprizone-induced memory decline in rat model of multiple sclerosis

Cuprizone is a neurotoxin with copper-chelating ability used in animal model of multiple sclerosis in which oxidative stress has been documented as one of the cascade in the pathogenesis. Moringa oleifera is a phytomedicinal plant with antioxidant and neuroprotective properties. This study aimed at evaluating the ameliorative capability of M. oleifera in cuprizone-induced behavioral and histopathological alterations in the prefrontal cortex and hippocampus of Wistar rats. Four groups of rats were treated with normal saline, cuprizone, M. oleifera and a combination of M. oleifera and cuprizone, for five weeks. The rats were subjected to Morris water maze and Y-maze to assess long and short-term memory respectively. The animals were sacrificed, and brain tissues were removed for histochemical and enzyme lysate immunosorbent assay for catalase, superoxide dismutase, and nitric oxide. Cuprizone significantly induced oxidative and nitrosative stress coupled with memory decline and cortico-hippocampal neuronal deficits; however, administration of M. oleifera significantly reversed the neuropathological deficits induced by cuprizone.

Oxidative stress is bane in chronic liver diseases: Clinical and experimental perspective

Oxidative stress plays an important role in the pathogenesis of various chronic liver diseases (CLD) and increasing evidence have confirmed the contributory role of oxidative stress in the pathogenesis of drugs and chemical-induced CLD. Chronic liver injury is manifested as necrosis, cholestasis, fibrosis, and cirrhosis. Chronic administration of anti-tubercular, anti-retroviral, immunosuppressive drugs is reported to induce free radical generation during their biotransformation in the liver. Further, these reactive intermediates are said to induce profibrogenic cytokines, several inflammatory markers, collagen synthesis during the progression of hepatic fibrosis. Oxidative stress and free radicals are reported to induce activation and proliferation of hepatic stellate cells in the injured liver leading to the progression of CLD. Hence, to counteract or to scavenge these reactive intermediates, several plant-derived antioxidant principles have been effectively employed against oxidative stress and came out with promising results in human and experimental models of CLD. This review summarizes the relationships between oxidative stress and different liver pathogenesis induced by drugs and xenobiotics, focusing upon different chronic liver injury induced by alcohol, antitubercular drugs and hyperactivity of antiretroviral drugs in HIV patients, viral hepatitis infection induced oxidative stress.

Chlorogenic acid ameliorates alcohol-induced liver injuries through scavenging reactive oxygen species

The key role of oxidative stress in alcoholic liver disease (ALD) has been established by the large body of evidence from previous studies. Excessive consumption of ethanol induces the production of a variety of reactive oxygen species (ROS) in the liver, such as superoxide, H₂O₂, and hydroxyl radical. These products activate oxidant-sensitive signaling cascades and modulators of apoptosis. Because ROS accumulation is closely related to ALD, a number of studies have investigated the benefits of antioxidants. Recent studies demonstrated that polyphenol chlorogenic acid (CGA) has antioxidant properties and health benefits, such as reduction of relative risk of cardiovascular diseases and hepatoprotective effects against acetaminophen toxicity. However, the protective effects of CGA against ALD have not been studied in detail. We hypothesize that CGA plays a role in preventing ALD through its antioxidant properties. In this study, we investigated the protective effects of CGA against liver injuries in vivo. Reduced alcohol-induced-steatosis, apoptotic cell death, and fibrosis due to reduced levels of oxidative stress were observed. These findings suggest that CGA treatment can be an effective approach to attenuate ALD through the suppression of oxidative stress.

The Effect of Calcium Dobesilate on Liver Damage in Experimental Obstructive Jaundice

Purpose/Aim of the study: Inflammation and oxidative stress are two significant factors affecting the degree of liver damage in obstructive jaundice. The aim of this study was to evaluate the effect of calcium dobesilate (CaDob), an effective antioxidant and anti-inflammatory drug, on damage to liver caused by experimental obstructive jaundice.

MATERIALS AND METHODS

30 rats in total were randomly placed into three groups, each group consisting of 10 rats. The sham group (Group 1) only received solely laparotomy. In the control group (Group 2), ligation was applied to the biliary tract and no treatment was implemented. In the CaDob group (Group 3), following ligation of the biliary tract, 100 mg/kg/day CaDob was implemented via an orogastric tube for a 10-day period. Liver tissue and blood samples were taken for histopathological and biochemical examination.

RESULTS

The CaDob group had significantly lower test values for serum liver functions when compared to the control group. Statistically lower levels of tissue malondialdehyde (MDA) and fluorescent oxidation products (FOP) were detected in the CaDob group, and the CaDob group had significantly higher levels of sulfydryl (SH) than the control group. Histopathological scores in the CaDob group were found out to be statistically less than the scores the control group received (p < 0.05).

CONCLUSIONS

CaDob treatment repaired the histpatological changes induced by bile duct ligation. The hepatoprotective effects of CaDob can be associated with its antioxidant properties of the drug.

Anti-fibrotic effects of Cuscuta chinensis with in vitro hepatic stellate cells and a thioacetamide-induced experimental rat model

CONTEXT

Cuscuta chinensis Lam. (Convolvulaceae) has been used as a traditional herbal remedy for treating liver and kidney disorders.

OBJECTIVE

Anti-fibrotic effects of C. chinensis extract (CCE) in cellular and experimental animal models were investigated.

MATERIALS AND METHODS

HSC-T6 cell viability, cell cycle and apoptosis were analysed using MTT assay, flow cytometry and Annexin V-FITC/PI staining techniques. Thioacetamide (TAA)-induced fibrosis model was established using Sprague Dawley rats (n = 10). Control, TAA, CCE 10 (TAA with CCE 10 mg/kg), CCE 100 (TAA with CCE 100 mg/kg) and silymarin (TAA with silymarin 50 mg/kg). Fibrosis was induced by TAA (200 mg/kg, i.p.) twice per week for 13 weeks. CCE and silymarin were administered orally two times per week from the 7th to 13th week. Fibrotic related gene expression (α-SMA, Col1α1 and TGF-β1) was measured by RT-PCR. Serum biomarkers, glutathione (GSH) and hydroxyproline were estimated by spectrophotometer using commercial kits.

RESULTS

CCE (0.05 and 0.1 mg/mL) and silymarin (0.05 mg/mL) treatment significantly (p < 0.01 and p < 0.001) induced apoptosis (11.56%, 17.52% for CCE; 16.50% for silymarin, respectively) in activated HSC-T6 cells, compared with control group (7.26%). Further, rat primary HSCs showed changes in morphology with CCE 0.1 mg/mL treatment. In in vivo studies, CCE (10 and 100 mg/kg) treatment ameliorated the TAA-induced altered levels of serum biomarkers, fibrotic related gene expression, GSH, hydroxyproline significantly (p < 0.05-0.001) and rescued the histopathological changes.

CONCLUSIONS

CCE can be developed as a potential agent in the treatment of hepatofibrosis.

Preventing oxygen free radical damage by proanthocyanidin in obstructive jaundice

OBJECTIVE

Tissue damage and endotoxemia in obstructive jaundice are attributed to the increase in oxygen free-radicals. We aimed at evaluating the possible protective effect of grape seed proanthocyanidin extract (GSPE), which is a potent exogenous free-radical scavenger and antioxidant.

MATERIAL AND METHODS

The study was performed at the Necmettin Erbakan University Meram School of Medicine Research and Application Center for Experimental Medicine Laboratory with ethical approval. 30 Wistar-Albino rats were used and were divided into 3 groups. The common bile duct was identified and only dissected in the first group (sham). Following dissection of the common bile duct it was ligated with 4/0 silk just above the pancreas in the second group (control). After ligation of the common bile duct, 100mg/kg/day GSPE was administered via orogastric lavage for 10 days in the third group.

RESULTS

Biochemical values revealed a statistically significant difference between Group I and the others. There was no difference between Group II and III regarding biochemical values. There was a statistically significant difference, however, between Group II and III with regards to nitric oxide levels. There was a statistically significant difference between Group I and the other groups concerning hepatic and pulmonary tissue damage on histopathologic evaluation. There was no difference among the groups with regards to renal tubular damage.

CONCLUSION

Proanthocyanidin is an effective natural antioxidant in decreasing the level of tissue damage caused by oxygen free-radicals.

Protective Effects of Ethyl Acetate Soluble Fraction of Limonium tetragonum on Diethylnitrosamine-Induced Liver Fibrosis in Rats

Diethylnitrosamine (DEN) is a potent toxic material that can cause necrosis and subsequent fibrosis in the liver. Based on the previously reported hepatoprotective effect of Limonium tetragonum against the proliferation of hepatic stellate cells, we tested the EtOAc soluble fraction of L. tetragonum extract (EALT) in a DEN-induced hepatotoxic rat model. The development of hepatotoxicity including mononuclear cell infiltration and fibrosis induced by intraperitoneal injections of DEN (70 mg/2 mL/kg body weight (b.w.) per week) was observed at 4, 6 and 8 weeks after the first DEN treatment. Administration of EALT (200 mg/kg body weight, per os (p.o.)) induced significant reductions in serum alanine transaminase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), and triglycerides (TG) in DEN-injected rats. Increased oxidative stress in DEN-induced liver fibrosis rats was diminished by EALT treatment through a decrease in malondialdehyde (MDA) and increase in superoxide dismutase (SOD). Histologic findings that included markedly attenuated mononuclear cell infiltration and fibrosis could be observed in liver samples from the EALT-treated groups. An extract of Hovenia dulcis fruit and Sylimarin were used as positive controls. The present study provides direct experimental evidence for EALT attenuated hepatic injury and fibrosis in DEN-treated mice. The L. tetragonum EtOAc fraction might be useful in treating fibrotic liver diseases.

Knockdown of histidine-rich calcium-binding protein (HRC) suppresses liver fibrosis by inhibiting the activation of hepatic stellate cells

The histidine-rich calcium-binding protein (HRC) is a regulator of Ca²⁺ homeostasis and it plays a significant role in hepatocellular carcinoma (HCC) progression. However, the relationship between HRC and liver fibrogenesis is still unknown. Our data demonstrates that HRC was upregulated in fibrotic liver and activated hepatic stellate cells (HSCs). TGF-β treatment increased α-SMA and HRC expression dose-dependently in HSCs. Repression of HRC reduced α-SMA, CTGF and collagen expression, and inhibited HSC proliferation and migration. In addition, we found that the anti-fibrosis effect of HRC knockdown was associated with endoplasmic reticulum (ER) stress. Silencing of HRC decreased the expression of ER stress and autophagy markers. Moreover, ER stress agonist thapsigargin (TG) enhanced, whereas ER stress antagonist 4-phenylbutyric acid (4-PBA) alleviated HSCs activation and autophagy. In conclusion, these data indicate that depletion of HRC inhibited HSC activation through the ER stress pathway, and HRC may be a potential regulator of liver fibrosis.

N-acetylcysteine Ameliorates Prostatitis via miR-141 Regulating Keap1/Nrf2 Signaling

Chronic prostatitis was the most common type of prostatitis and oxidative stress was reported to be highly elevated in prostatitis patients. In this study, we determined the effect of N-acetylcysteine (NAC) on prostatitis and the molecular mechanism involved in it. Male Sprague-Dawley rats were divided into three groups: control group (group A, n = 20), carrageenan-induced chronic nonbacterial prostatitis (CNP) model group (group B, n = 20), and carrageenan-induced CNP model group with NAC injection (group C, n = 20). Eye score, locomotion score, inflammatory cell count, cyclooxygenase 2 (COX2) expression, and Evans blue were compared in these three groups. The expression of miR-141 was determined by quantitative real-time PCR (qRT-PCR). Moreover, protein expressions of Kelch-like ECH-associated protein-1 (Keap1) and nuclear factor erythroid-2 related factor 2 (Nrf2) and its target genes were examined by Western blot. Luciferase reporter assay was performed in RWPE-1 cells transfected miR-141 mimic or inhibitor and the plasmid carrying 3'-UTR of Keap1. The value of eye score, locomotion score, inflammatory cell count, and Evans blue were significantly decreased in group C, as well as the expression of COX2, when comparing to that of group B. These results indicated that NAC relieved the carrageenan-induced CNP. Further, we found that NAC increased the expression of miR-141 and activated the Keap1/Nrf2 signaling. Luciferase reporter assay revealed that miR-141 mimic could suppress the activity of Keap1 and stimulate the downstream target genes of Nrf2. In addition, miR-141 inhibitor could reduce the effect of NAC on prostatitis. NAC ameliorates the carrageenan-induced prostatitis and prostate inflammation pain through miR-141 regulating Keap1/Nrf2 signaling.

Protective vascular effects of quercitrin in acute TNBS-colitis in rats: the role of nitric oxide

Quercitrin (quercetin 3-rhamnoside) is a bioflavonoid with anti-inflammatory activity in experimental colitis.

In vitro detection of diesel exhaust particles induced human lung carcinoma epithelial cells damage and the effect of resveratrol

People are taking up antioxidants in their daily diet and being exposed to a potential diesel exhaust particles (DEP)-containing environment. Thus it is important to study in vitro cellular responses when cells are exposed to DEP with or without antioxidant treatment. The investigation of DEP and resveratrol (RES) on cellular biophysical and biochemical changes is needed to better understand the mechanisms of DEP and RES in mammalian cells. A combination of two non-invasive techniques (atomic force microscopy, AFM, and Raman spectroscopy, RM) and multimodal tools were applied to evaluate the biophysical, biochemical alterations and cytokine, membrane potential and cell cycle of cells with or without RES pretreatment to different times of DEP exposure. AFM results indicated that RES protected cells from DEP-induced damage to cytoskeleton and cell architectures, and noted that RES treatments also attenuated DEP-induced alterations in cell elasticity and surface adhesion force over DEP incubation time. RM monitored the changes in characteristic Raman peak intensities of DNA and protein over the DEP exposure time for both RES and non-RES treated groups. The cytokine and chemokine changes quantified by Multiplex ELISA revealed that the inflammatory responses were enhanced with the increase in DEP exposure time and that RES enhanced the expression levels of cytokine and chemokine. This work demonstrated that significant biophysical and biochemical changes in cells might be relevant to early pathological changes induced by DEP damage. Copyright © 2016 John Wiley & Sons, Ltd.