Prophylactic effect of resveratrol against ethinylestradiol-induced liver cholestasis

Therapeutic approaches for cholestatic liver diseases: the role of nitric oxide pathway

Cholestasis describes bile secretion or flow impairment, which is clinically manifested with fatigue, pruritus, and jaundice. Neutrophils play a crucial role in many diseases such as cholestasis liver diseases through mediating several oxidative and inflammatory pathways. Data have been collected from clinical, in vitro, and in vivo studies published between 2000 and December 2021 in English and obtained from the PubMed, Google Scholar, Scopus, and Cochrane libraries. Although nitric oxide plays an important role in the pathogenesis of cholestatic liver diseases, excessive levels of NO in serum and affected tissues, mainly synthesized by the inducible nitric oxide synthase (iNOS) enzyme, can exacerbate inflammation. NO induces the inflammatory and oxidative processes, which finally leads to cell damage. We found that natural products such as baicalin, curcumin, resveratrol, and lycopene, as well as chemical likes ursodeoxycholic acid, dexamethasone, rosuvastatin, melatonin, and sildenafil, are able to markedly attenuate the NO production and iNOS expression, mainly through inducing the nuclear factor κB (NF-κB), Janus kinase and signal transducer and activator of transcription (JAK/STAT), and toll like receptor-4 (TLR4) signaling pathways. This study summarizes the latest scientific data about the bile acid signaling pathway, the neutrophil chemotaxis recruitment process during cholestasis, and the role of NO in cholestasis liver diseases. Literature review directed us to propose that suppression of NO and its related pathways could be a therapeutic option for preventing or treating cholestatic liver diseases.

Dietary Polyphenols Alleviate Autoimmune Liver Disease by Mediating the Intestinal Microenvironment: Challenges and Hopes

Autoimmune liver disease is a chronic liver disease caused by an overactive immune response in the liver that imposes a significant health and economic cost on society. Due to the side effects of existing medicinal medications, there is a trend toward seeking natural bioactive compounds as dietary supplements. Currently, dietary polyphenols have been proven to have the ability to mediate gut-liver immunity and control autoimmune liver disease through modulating the intestinal microenvironment. Based on the preceding, this Review covers the many forms of autoimmune liver illnesses, their pathophysiology, and the modulatory effects of polyphenols on immune disorders. Finally, we focus on how polyphenols interact with the intestinal milieu to improve autoimmune liver disease. In conclusion, we suggest that dietary polyphenols have the potential as gut-targeted modulators for the prevention and treatment of autoimmune liver disease and highlight new perspectives and critical issues for future pharmacological applications.

GANE can Improve Lung Fibrosis by Reducing Inflammation via Promoting p38MAPK/TGF-β1/NF-κB Signaling Pathway Downregulation

There is a trend to use nanoparticles as distinct treatments for cancer treatment because they have overcome many of the limitations of traditional drug delivery systems. Gallic acid (GA) is an effective polyphenol in the treatment of tissue injuries. In this study, GA was loaded onto niosomes to produce gallic acid nanoemulsion (GANE) using a green synthesis technique. GANE's efficiency, morphology, UV absorption, release, and Fourier-transform infrared spectroscopy (FTIR) analysis were evaluated. An in vitro study was conducted on the A549 lung carcinoma cell line to determine the GANE cytotoxicity. Also, our study was extended to evaluate the protective effect of GANE against lipopolysaccharide (LPS)-induced pulmonary fibrosis in rats. GANE showed higher encapsulation efficiency and strong absorption at 280 nm. Transmission electron microscopy presented a spherical shape of the prepared nanoparticles, and FTIR demonstrated different spectra for the free gallic acid sample compared to GANE. GANE showed cytotoxicity for the A549 carcinoma lung cell line with a low IC₅₀ value. It was found that oral administration of GANE at 32.8 and 82 mg/kg.b.w. and dexamethasone (0.5 mg/kg) provided significant protection against LPS-induced pulmonary fibrosis. GANE enhanced production of superoxide dismutase, GPx, and GSH. It simultaneously reduced the MDA level. The GANE and dexamethasone, induced the production of IL-4, but suppressed TNF-α and IL-6. On the other hand, the lung p38MAPK, TGF-β1, and NF-κB gene expression was downregulated in rats administrated with GANE when compared with the LPS-treated rats. Histological studies confirmed the effective effect of GANE as it had a lung-protective effect against LPS-induced lung fibrosis. It was noticed that GANE can inhibit oxidative stress, lipid peroxidation, and cytokines and downregulate p38MAPK, TGF-β1, and NF-κB gene expression to suppress the proliferation and migration of lung fibrotic cells.

Resveratrol: A Potential Protector Against Benzo[a]pyrene- Induced Lung Toxicity

<b>Background and Objective:</b> Benzo[a]pyrene (B[a]P), a major component of lipophilic pollutants then can be translated to diffluent substances. The aim of t he present article was to investigate protective activity of resveratrol against lung toxicity induced by B[a]P. Material and Methods: Male Sprague-Dawley rats were randomly assigned to 6 groups (6 animals/group): 3 negative control groups, control positive, B[a]P (20 mg kg<sup></sup><sup>1</sup> b.wt., resveratrol (50 mg kg<sup></sup><sup>1</sup> b.wt.)-B[a]P and vitamin C (1 g kg<sup></sup><sup>1</sup> b.wt.)-B[a]P groups. <b>Results:</b> The daily oral administration of the resveratrol (50 mg kg<sup></sup><sup>1</sup> b.wt.) and vitamin C (1 g kg<sup></sup><sup>1</sup> b.wt.) for 30 days to rats treated with B[a]P (20 mg kg<sup></sup><sup>1</sup> b.wt.) resulted in a significant improve plasma cholesterol, triglyceride and HDL-C as well as serum TNF-α, TBARS, IL-2,IL-6, haptoglobin, histamine, IgA, Ig E,Ig G and Ig M in B[a]P treated rats. On the other hand oral administration of resveratrol elevated the SOD, GPx and GR gene expression in lung rats treated with B[a]P. Furthermore, resveratrol and vitamin C nearly normalized these effects in lung histoarchitecture. <b>Conclusion:</b> The obtained biochemical, molecular biology and histological results of this study proved the lung protective activity of resveratrol against B[a]P induced lung toxicity in rats.

Resveratrol: Isolation, and Its Nanostructured Lipid Carriers, Inhibits Cell Proliferation, Induces Cell Apoptosis in Certain Human Cell Lines Carcinoma and Exerts Protective Effect Against Paraquat-Induced Hepatotoxicity

Resveratrol (RES) (trans-3, 5,-4'-trihydroxystilebene) is a multi-biofunctional compound found in a variety of plants such as grapes and mulberries. Studies of nanoencapsulated resveratrol have indicated that this compound can inhibit the growth of cancer cells and free radicals. The aim of this study was to isolate resveratrol from Vitis vinifera, develop and evaluate resveratrol nanostructured lipid carriers (NLCs) and/or resveratrol encapsulated chitosan-coated nanostructured lipid carriers (CSNLCs) using low-viscous chitosan for anticancer therapy. In addition, our study was carried out to examine the prophylactic potential of RES, NLC, and CSNLC on paraquat-induced injury in rat hepatocytes. In this study we isolated resveratrol and encapsulated NLCs in phosphate-buffered saline solution using a phase inversion method. In addition, CSNLCs were prepared by ionic gelation method of NLCs using chitosan. NLCs and CSNLCs were then characterized for their particle size, zeta potential, morphology, and entrapment efficiency. Furthermore, NLCs and CSNLCs were evaluated for their cytotoxic effect on Hep-G2, human HCT-116 (colorectal cancer cell line), lymphoblastic leukemia (1301), and human MCF-7 (Michigan Cancer Foundation-7) cells as well as their effect on caspase-3 and death receptor (DR-4). In addition, incubation of hepatocytes with paraquat resulted in increased formation of TBARS (thiobarbituric acid reactive substances) with a parallel increase in lactate dehydrogenase (LDH) leakage at 1 h after incubation. Time-dependent depletion of cellular glutathione (GSH) was observed starting 2 h after incubation with paraquat. The mean particle size of NLC and CSNLC were 67.0 and 98.41 nm, zeta potential were (-) 24.8 and (+) 31.6 mV, entrapment efficiency were 74.15% and 85.46%, respectively, with the observed shapes of nanoparticle being spherical. The treatment of Hep-G2, human HCT-116, lymphoblastic leukemia (1301), and human MCF-7 cells with NLC led to high inhibition in the cell proliferation as concluded by the low IC₅₀ values 27.7, 17.43, 35.39, and 47.66 μg/mL, respectively, whereas CSNLC had high cytotoxic effect on Hep-G2, human HCT-116, lymphoblastic leukemia (1301), and human MCF-7 cells with low IC₅₀ values 13.29, 10.56, 16.79 and 22.60 μg/mL, respectively. Both NLC and CSNLC possess apoptotic properties through activation of the caspase-3 and death receptor (DR-4). In addition, incubation of hepatocytes with RES, NLC, and CSNLC markedly protected against paraquat-induced formation of TBARS, increase in LDH leakage, and prevented GSH depletion. The most effective doses for ethyl acetate, ethanolic, and aqueous extracts were 7.5, 10, and 12.5 μg, respectively. The results presented here may suggest that nanoencapsulated resveratrol isolated from the stems of V. vinifera to obtain NLC and CSNLC possess anticancer and apoptotic effects on cell proliferation, and therefore, can be used as new approach of pharmaceutical drugs. In addition, the results clearly suggest that the RES, NLC, and CSNLC exerted protective effect against cytotoxicity induced by paraquat. On the contrary, the effect decreased in order of CSNLC, NLC, and RES.

Natural products for the prevention and treatment of cholestasis: A review

Cholestasis is a common manifestation of decreased bile flow in various liver diseases. It results in fibrosis and even cirrhosis without proper treatment. It is believed that a wide range of factors, including transporter dysfunction, oxidative stress, inflammatory damage, and immune disruption, can cause cholestasis. In recent years, natural products have drawn much attention for specific multiple-target activities in diseases. Many attempts have been made to investigate the anticholestatic effects of natural products with advanced technology. This review summarizes recent studies on the biological activities and mechanisms of recognized compounds for cholestasis treatment. Natural products, including various flavonoids, phenols, acids, quinones, saponins, alkaloids, glycosides, and so on, function as comprehensive regulators via ameliorating oxidative stress, inflammation, and apoptosis, restoring bile acid balance with hepatic transporters, and adjusting immune disruption. Moreover, in this progress, nuclear factor erythroid 2-related factor 2, reactive oxygen species production, heme oxygenase-1, NF-κB, cholesterol 7 alpha-hydroxylase, and farnesoid X receptors are thought as main targets for the activity of natural products. Therefore, this review presents the detailed mechanisms that include multiple targets and diverse signalling pathways. Natural products are the valuable when seeking novel therapeutic agents to treat cholestatic liver diseases.

Resveratrol Modulates miR-34a in Cardiotoxicity Induced by Isoproterenol

Acute myocardial infarction is a major cause of death and disability worldwide. This study was designed to elucidate the effect of resveratrol (RES) in isoproterenol (ISO)-challenged myocardial injury in rats. Male Sprague-Dawley rats were randomly allocated to four groups (10 rats/group): negative, control positive ISO (85 mg/kg), Propranolol/ISO, and RES/ISO. RES (50 mg/kg) improved plasma lactate dehydrogenase, creatine kinase, and cardiac troponin T; brain natriuretic peptide, interleukin-10, vascular endothelial growth factor, and transforming growth factor-β1; as well as cardiac superoxide dismutase, malondialdehyde, and total protein kinase-1 (Akt-1) levels. In addition, RES reduced the expression of cardiac inducible nitric oxide synthase and microRNA-34a, as well as p38 mitogen-activated protein kinase levels compared with positive control group. In conclusion, RES could reduce the degree of MI induced by ISO by improving the antioxidant, antiapoptotic, and anti-inflammatory capacities of the body.

Beneficial and Deleterious Effects of Female Sex Hormones, Oral Contraceptives, and Phytoestrogens by Immunomodulation on the Liver

The liver is considered the laboratory of the human body because of its many metabolic processes. It accomplishes diverse activities as a mixed gland and is in continuous cross-talk with the endocrine system. Not only do hormones from the gastrointestinal tract that participate in digestion regulate the liver functions, but the sex hormones also exert a strong influence on this sexually dimorphic organ, via their receptors expressed in liver, in both health and disease. Besides, the liver modifies the actions of sex hormones through their metabolism and transport proteins. Given the anatomical position and physiological importance of liver, this organ is evidenced as an immune vigilante that mediates the systemic immune response, and, in turn, the immune system regulates the hepatic functions. Such feedback is performed by cytokines. Pro-inflammatory and anti-inflammatory cytokines are strongly involved in hepatic homeostasis and in pathological states; indeed, female sex hormones, oral contraceptives, and phytoestrogens have immunomodulatory effects in the liver and the whole organism. To analyze the complex and interesting beneficial or deleterious effects of these drugs by their immunomodulatory actions in the liver can provide the basis for either their pharmacological use in therapeutic treatments or to avoid their intake in some diseases.

Protective Effects of Ginsenosides on 17α-Ethynyelstradiol-Induced Intrahepatic Cholestasis via Anti-Oxidative and Anti-Inflammatory Mechanisms in Rats

The present study was designed to assess the effects and potential mechanisms of ginsenosides on 17[Formula: see text]-ethynyelstradiol (EE)-induced intrahepatic cholestasis (IC). Ginsenoside at doses of 30, 100, 300[Formula: see text]mg/kg body weight was intragastrically (i.g.) given to rats for 5 days to examine the effect on EE-induced IC. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and total bile acid (TBA) were measured. Hepatic malondialdehyde (MDA) content and superoxide dismutase (SOD) activity were determined. Protein expression of proinflammatory cytokines TNF-[Formula: see text], IL-6 and IL-1[Formula: see text] was analyzed by immunohistochemistry and Western blot. Results indicated that ginsenosides remarkably prevented EE-induced increase in the serum levels of AST, ALT, ALP and TBA. Moreover, the elevation of hepatic MDA content induced by EE was significantly reduced, while hepatic SOD activities were significantly increased when treated with ginsenosides. Histopathology of the liver tissue showed that pathological injuries were relieved after treatment with ginsenosides. In addition, treatment with ginsenosides could significantly downregulate the protein expression of TNF-[Formula: see text], IL-6 and IL-1[Formula: see text] compared with EE group. These findings indicate that ginsenosides exert the hepatoprotective effect on EE-induced intrahepatic cholestasis in rats, and this protection might be attributed to the attenuation of oxidative stress and inflammation.

Mitigating Effect of Resveratrol on the Structural Changes of Mice Liver and Kidney Induced by Cadmium; A Stereological Study

Exposure to cadmium (Cd) has harmful effects on the liver and kidney. Resveratrol (RES) is an herbal substance that functions as a protective mediator. This study aimed to investigate the effects of RES on the histology of liver and kidney in Cd-exposed mice. Male mice were divided into 4 groups daily receiving normal saline (1 mL normal saline/d), Cd (1 mg/kg/d), RES (20 mg/kg/d), and Cd plus RES, respectively. After 4 weeks, the liver and kidney components were evaluated using stereological methods. The total volume and number of hepatocytes, and volume of fibrous tissue were respectively increased by 34%, 58%, and a 3-fold in the Cd-exposed mice in comparison to the control animals (P < 0.03). On the other hand, the volume of the main vasculature (sinusoids and central veins) was decreased by 36% in the Cd group compared to the control mice (P < 0.03). Considering the kidney, the results showed a 3-fold increase in the total glomeruli volume and a 7-fold increase in fibrous tissue in the Cd-treated group compared to the control mice (P < 0.03). After Cd treatment, a 32% reduction was observed in the volume and length of the proximal and distal convoluted tubules. RES-treatment alone did not induce any structural changes. In comparison to the Cd group, an increase in the normal components of the liver and kidney and a decrease in the formation of the fibrous and degenerated tissues were observed in the Cd+RES-treated mice (P < 0.03).

Critical review of resveratrol in xenobiotic-induced hepatotoxicity

Use of natural products is increasingly popular. In fact, many patients with liver diseases self-medicate with herbal supplements. Resveratrol (RSV), in particular, is a common natural product that can reduce injury in experimental models of liver disease. Xenobiotic hepatotoxicity is a particularly important area-of-need for therapeutics. Drug-induced liver injury, for example, is the most common cause of acute liver failure (ALF) and ALF-induced deaths in many countries. Importantly, RSV protects against hepatotoxicity in animal models in vivo caused by several drugs and chemicals and may be an effective intervention. Although many mechanisms have been proposed to explain the protection, not all are consistent with other data. Furthermore, RSV suffers from other issues, including limited bioavailability due to extensive hepatic metabolism. The purpose of this article is to summarize recent findings on the protective effects of RSV in xenobiotic-induced liver injury and other forms of liver injury and to provide a critical review of the underlying mechanisms. New mechanisms that are more consistent with data emerging from the toxicology field are suggested. Efforts to move RSV into clinical use are also considered. Overall, RSV is a promising candidate for therapeutic use, but additional studies are needed to better understand its effects.

Resveratrol effectively attenuates α-naphthyl-isothiocyanate-induced acute cholestasis and liver injury through choleretic and anti-inflammatory mechanisms

AIM

α-Naphthylisothiocyanate (ANIT) is a well-characterized cholestatic agent for rats. The aim of this study was to examine whether resveratrol could attenuate ANIT-induced acute cholestasis and liver injury in rats.

METHODS

SD rats were treated with resveratrol (15 or 30 mg/kg, ip) or a positive control drug ursodeoxycholic acid (100 mg/kg, po) for 5 consecutive days followed by a single dose of ANIT (60 mg/kg, po). Bile flow, and serum biochemical markers and bile constituents were measured 48 h after ANIT administration. Hepatic levels of oxidative repair enzymes (glutathione peroxidase, catalase and MnSOD), myeloperoxidase activity, TNF-α, IL-6 and ATP content, as well as the expression of liver transporter genes and proteins were assayed.

RESULTS

ANIT exposure resulted in serious cholestasis and liver injury, as shown by marked neutrophil infiltration in liver, dramatically increased serum levels of ALT, AST, GGT, ALP, TBA, TBIL, IBIL and DBIL, and significantly decreased bile excretion and biliary output of GSH and HCO3(-). ANIT significantly increased TNF-α and IL-6 release and myeloperoxidase activity, decreased mitochondrial biogenesis in liver, but had little effect on hepatic oxidative repair enzymes and ATP content. Furthermore, ANIT significantly decreased the expression of Mrp2, FXR and Cyp7a1, markedly increased Mrp3 expression in liver. Pretreatment with resveratrol attenuated ANIT-induced acute cholestasis and liver injury, and other pathological changes. Pretreatment with ursodeoxycholic acid was less effective.

CONCLUSION

Resveratrol effectively attenuates ANIT-induced acute cholestasis and liver injury in rats, possibly through suppression of neutrophil infiltration, as well as upregulation of expression of hepatic transporters and enzymes, thus decreasing accumulation of bile acids.