Ameliorative effects of silymarin on HCl-induced acute lung injury in rats; role of the Nrf-2/HO-1 pathway

The clinical anti-inflammatory effects and underlying mechanisms of silymarin

Inflammatory conditions are key mediators in the progression of various diseases. Silymarin, derived from Silybum marianum seeds and fruits, has shown efficacy in treating a range of liver diseases. The expanding corpus of research on silymarin highlights its promising role in preventing and managing inflammatory conditions and autoimmune without adverse effects. This review discusses the absorption, metabolism, and anti-inflammatory mechanisms of silymarin, exploring its impact on the secretion of inflammatory factors, such as nuclear factor kappa B (NF-κB) pathway, mitogen-activated protein kinase (MAPK) pathway, and antioxidant pathway. We delve into its disease-modifying potential for clinical applications, thereby laying a theoretical foundation for further silymarin research and clinical studies.

The Radiosensitizing Potentials of Silymarin/Silibinin in Cancer: A Systematic Review

INTRODUCTION

Although radiotherapy is one of the main cancer treatment modalities, exposing healthy organs/tissues to ionizing radiation during treatment and tumor resistance to ionizing radiation are the chief challenges of radiotherapy that can lead to different adverse effects. It was shown that the combined treatment of radiotherapy and natural bioactive compounds (such as silymarin/silibinin) can alleviate the ionizing radiation-induced adverse side effects and induce synergies between these therapeutic modalities. In the present review, the potential radiosensitization effects of silymarin/silibinin during cancer radiation exposure/radiotherapy were studied.

METHODS

According to the PRISMA guideline, a systematic search was performed for the identification of relevant studies in different electronic databases of Google Scholar, PubMed, Web of Science, and Scopus up to October 2022. We screened 843 articles in accordance with a predefined set of inclusion and exclusion criteria. Seven studies were finally included in this systematic review.

RESULTS

Compared to the control group, the cell survival/proliferation of cancer cells treated with ionizing radiation was considerably less, and silymarin/silibinin administration synergistically increased ionizing radiation-induced cytotoxicity. Furthermore, there was a decrease in the tumor volume, weight, and growth of ionizing radiation-treated mice as compared to the untreated groups, and these diminutions were predominant in those treated with radiotherapy plus silymarin/ silibinin. Furthermore, the irradiation led to a set of biochemical and histopathological changes in tumoral cells/tissues, and the ionizing radiation-induced alterations were synergized following silymarin/silibinin administration (in most cases).

CONCLUSION

In most cases, silymarin/silibinin administration could sensitize the cancer cells to ionizing radiation through an increase of free radical formation, induction of DNA damage, increase of apoptosis, inhibition of angiogenesis and metastasis, etc. However, suggesting the use of silymarin/silibinin during radiotherapeutic treatment of cancer patients requires further clinical studies.

Evaluation of the Protective Effect of Citral, Silymarin, and Thymoquinone on Methotrexate-Induced Lung Injury in Rats

Objectives

Several studies have reported that methotrexate is an anti-cancer and immunosuppressive drug leading to lung injury. Therefore, the present study aimed to investigate the protective effects of silymarin, citral, and thymoquinone on methotrexate-induced pulmonary toxicity.

Methods

Forty-eight rats were divided into six groups, including healthy, Methotrexate, and drug carrier control groups and silymarin, citral, and thymoquinone treatment groups. At the end of the experiment, the studied rats were anesthetized and sacrificed by CO₂. Lung tissue samples were isolated to measure the antioxidant activity and histopathological evaluation.

Results

In the thymoquinone treatment group, the concentration of total antioxidant capacity and Malondialdehyde increased and decreased significantly, respectively, compared to the methotrexate group. The histopathological evaluation of the lung of the methotrexate group showed hemorrhage and congestion, the nodule-like accumulation of mononuclear inflammatory lymphocytes around the blood vessel, a small number of neutrophils around the blood vessel, and the inflammatory cells around the small vessels. However, no significant pathological alterations were observed in the treatment groups, especially the thymoquinone treatment group.

Conclusion

Thymoquinone has the greatest protective effect on methotrexate-induced lung injury, probably due to its antioxidant effect.

The effect of Moringa oleifera leaf extracts against urethane-induced lung cancer in rat model

Lung cancer is one of the most common malignancies in the world, and chemotherapy can have unfavorable side effects. The aim of the present study is to evaluate the therapeutic anticancer role of Moringa oleifera leaf extracts (MLE) in urethane-induced lung cancer in adult male albino rats as compared to standard chemotherapy. Rats were categorized into four groups (10 rats/group), including negative control rats, urethane lung cancer model rats, MLE-treated lung cancer rats, and cisplatin-treated rats. Estimation of lung index, some biochemical markers of oxidative stress, quantitative real-time polymerase chain reaction (qRT-PCR), and histopathology and transmission electron microscopy were performed. The lung index was significantly increased about one-fold in urethane lung cancer model rats, but it decreased after MLE treatment. Also, MLE was able to improve the induced changes in glutathione, superoxide dismutase, and malondialdehyde concentration to be 3.8 ± 0.4 mg/g, 900.6 ± 58 U/g, and 172 ± 24 nmol/g, respectively. Additionally, after MLE treatment, the expression of EGFR-mRNA increased by about 50%. Our light and electron microscopic examination revealed that urethane group showed abnormally distributed excessive collagen fibers and the development of papillary adenocarcinoma from hyperplastic Clara cells in the lumen of terminal bronchiole with bronchiolar wall thickening, alveolar collapse, and inflammation. MLE group has moderate amount of collagen fiber and absence of tumor mass and provided more or less restoration of normal lung histology. Moreover, MLE was able to ameliorate the induced changes in mucin and PCNA positive cells in the lung by 10.8 ± 2.3%. Collectively, the current study showed that MLE could be used as anticancer agents alleviating changes associated with lung cancer in a urethane-induced lung cancer bearing rats thereby representing alternative options to toxic chemotherapy.

Design and optimization of silymarin loaded in lyophilized fast melt tablets to attenuate lung toxicity induced via HgCl2 in rats

The present study aimed to develop fast melting tablets (FMTs) using silymarin (SM) owing to FMTs rapid disintegration and dissolution. FMTs represent a pathway to help patients to increase their compliance level of treatment via facile administration without water or chewing beside reduction cost. One of the methods for FMTs formulation is lyophilization. Optimization of SM-FMTs was developed via a 32 factorial design. All prepared SM-FMTs were evaluated for weight variation, thickness, breaking force, friability, content uniformity, disintegration time (DT), and % SM released. The optimized FMT formula was selected based on the criteria of scoring the fastest DT and highest % SM released after 10 min (Q10). Optimized FMT was subjected to Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), and scanning electron microscopy (SEM) besides investigating its lung-protective efficacy. All SM-FMT tablets showed acceptable properties within the pharmacopeial standards. Optimized FMT (F7) scored a DT of 12.5 ± 0.64 Sec and % SM released at Q10 of 82.69 ± 2.88%. No incompatibilities were found between SM and excipients, it showed a porous structure under SEM. The optimized formula decreased cytokines, up-regulated miRNA133a, and down-regulated miRNA-155 and COX-2 involved in the protection against lung toxicity prompted by HgCl2 in a manner comparable to free SM at the same dosage.

Combined Silymarin and Cotrimoxazole Therapy Attenuates Pulmonary Fibrosis in Experimental Paracoccidioidomycosis

Paracoccidioidomycosis (PCM), which mainly affects rural workers, is a systemic mycosis caused by the Paracoccidioides genus that induces pulmonary sequelae in most adult patients, causing serious disability and impairing their quality of life. Silymarin is herbal medicine with an effective antifibrotic activity. Considering that in PCM, antifibrotic treatment is still not available in pulmonary fibrosis, we aimed to evaluate combined silymarin and cotrimoxazole (CMX) therapy via the intratracheal route in BALB/c mice infected with P. brasiliensis yeast. After 12 weeks of treatment, the lungs were collected for the determination of fungal burden, production of OH-proline, deposition of collagen fibers, pulmonary concentrations of cytokines, and expression of fibronectin, α-SMA, MMP-2, MMP-9, and TIMP-2. Spleen cell cultures were also performed. Our results showed that infected mice treated with combined silymarin/CMX showed lower deposition of collagen fibers in the lungs and lower pulmonary concentrations of hydroxyproline than the placebo groups. Decreased levels of TGF-β1 and fibronectin and high levels of MMP-2 and IFN-γ were also observed in this group of mice. Collectively, our findings indicate that the combination of antifungal treatment with silymarin has a potent antifibrotic effect associated with an immunomodulatory effect that potentializes the antifungal immune response.

A Review on Herbal Secondary Metabolites Against COVID-19 Focusing on the Genetic Variants of SARS-CoV-2

Context: An outbreak of the new coronavirus disease 2019 (COVID-19) was reported in Wuhan, China, in December 2019, subsequently affecting countries worldwide and causing a pandemic. Although several vaccines, such as mRNA vaccines, inactivated vaccines, and adenovirus vaccines, have been licensed in several countries, the danger of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants persists. To date, Alpha (B.1.1.7), Beta (B.1.351, B.1.351.2, B.1.351.3), Delta (B.1.617.2, AY.1, AY.2, AY. 3), Gamma (P.1, P.1.1, P.1.2), and Iota (B.1 .526) circulating in the United States, Kappa (B.1.617.1) in India, Lambda (C.37) in Peru and Mu (B.1.621) in Colombia are considered the variants of concern and interest. Evidence Acquisition: Data were collected through the end of August 2021 by searching PubMed, Scopus, and Google Scholar databases. There were findings from in silico, in vitro cell-based, and non-cell-based investigations. Results: The potential and safety profile of herbal medicines need clarification to scientifically support future recommendations regarding the benefits and risks of their use. Conclusions: Current research results on natural products against SARS-CoV-2 and variants are discussed, and their specific molecular targets and possible mechanisms of action are summarized.

Amelioration of Endotoxin-Induced Acute Lung Injury and Alveolar Epithelial Cells Apoptosis by Simvastatin Is Associated with Up-Regulation of Survivin/NF-kB/p65 Pathway

Disruption of the alveolar−endothelial barrier caused by inflammation leads to the progression of septic acute lung injury (ALI). In the present study, we investigated the beneficial effects of simvastatin on the endotoxin lipopolysaccharide (LPS)-induced ALI and its related mechanisms. A model of ALI was induced within experimental sepsis developed by intraperitoneal injection of a single non-lethal LPS dose after short-term simvastatin pretreatment (10−40 mg/kg orally). The severity of the lung tissue inflammatory injury was expressed as pulmonary damage scores (PDS). Alveolar epithelial cell apoptosis was confirmed by TUNEL assay (DNA fragmentation) and expressed as an apoptotic index (AI), and immunohistochemically for cleaved caspase-3, cytochrome C, and anti-apoptotic Bcl-xL, an inhibitor of apoptosis, survivin, and transcriptional factor, NF-kB/p65. Severe inflammatory injury of pulmonary parenchyma (PDS 3.33 ± 0.48) was developed after the LPS challenge, whereas simvastatin significantly and dose-dependently protected lung histology after LPS (p < 0.01). Simvastatin in a dose of 40 mg/kg showed the most significant effects in amelioration alveolar epithelial cells apoptosis, demonstrating this as a marked decrease of AI (p < 0.01 vs. LPS), cytochrome C, and cleaved caspase-3 expression. Furthermore, simvastatin significantly enhanced the expression of Bcl-xL and survivin. Finally, the expression of survivin and its regulator NF-kB/p65 in the alveolar epithelium was in strong positive correlation across the groups. Simvastatin could play a protective role against LPS-induced ALI and apoptosis of the alveolar−endothelial barrier. Taken together, these effects were seemingly mediated by inhibition of caspase 3 and cytochrome C, a finding that might be associated with the up-regulation of cell-survival survivin/NF-kB/p65 pathway and Bcl-xL.

Chronic Intermittent Hypoxia Reduces the Effects of Glucosteroid in Asthma via Activating the p38 MAPK Signaling Pathway

Aims

Obstructive sleep apnea (OSA) is a risk factor for steroid-resistant (SR) asthma. However, the underlying mechanism is not well defined. This study aimed to investigate how chronic intermittent hypoxia (CIH), the main pathophysiology of OSA, influenced the effects of glucocorticoids (GCs) on asthma.

Main Methods

The effects of dexamethasone (Dex) were determined using the ovalbumin (OVA)-challenged mouse model of asthma and transforming growth factor (TGF)-β treated airway smooth muscle cells (ASMCs), with or without CIH. The p38 MAPK signaling pathway activity was then detected in the mouse (n = 6) and ASMCs models (n = 6), which were both treated with the p38 MAPK inhibitor SB239063.

Key Findings

Under CIH, mouse pulmonary resistance value, inflammatory cells in bronchoalveolar lavage fluid (BALF), and inflammation scores increased in OVA-challenged combined with CIH exposure mice compared with OVA-challenged mice (p < 0.05). These indicators were similarly raised in the OVA + CIH + Dex group compared with the OVA + Dex group (P < 0.05). CIH exposure enhanced the activation of the p38 MAPK pathway, oxidative stress injury, and the expression of NF-κB both in lung tissue and ASMCs, which were reversed by treatment with Dex and SB239063. In the in vitro study, treatment with Dex and SB239063 decreased ASMCs proliferation induced by TGF-β combined with CIH and suppressed activation of the p38 MAPK pathway, oxidative stress injury, and NF-κB nuclear transcription (p < 0.05).

Significance

These results indicated that CIH decreased GC sensitivity by activating the p38 MAPK signaling pathway.

Effect of Silymarin Supplementation in Lung and Liver Histological Modifications during Exercise Training in a Rodent Model

BACKGROUND

Exercise training induces adaptive physiological and morphological modifications in the entire organism; however, excessive loads of training may increase damage in tissues. The purpose of this study was to evaluate the effect of silymarin in lung and liver histological changes in rats subjected to exercise training (ET).

METHODS

Male Wistar rats were subjected to an 8-week ET treadmill program 5 days per week, 60 min/session, and were previously administered 100 mg ascorbic acid or 100 mg of silymarin.

RESULTS

Silymarin increased alveolar and bronchial muscle size, improve vascularization, and reduced tissue inflammation. In liver, silymarin promoted the reduction of lipid content.

CONCLUSION

Silymarin supplementation may improve inflammation in pulmonary tissue after 8 weeks of the ET treadmill program, improve cell recovery, and reduce intrahepatic lipid content.

Potential of rosmarinic acid to ameliorate toxic effects of diethyl methoxy thio‑phosphoryl thio‑succinate on albino wistar rats' lung, mast cell infiltration inhibitory pathway

Malathion (MA) is a widely used pesticide in agriculture. It can cause toxicity in different organs of the body. Rosmarinic acid (RO) is found in rosemary extract that can be absorbed through gastrointestinal tract mucosa with potent antioxidant, and anti-inflammatory potential. The current study is designed to investigate the potential of RO to protect the lung after MA administration. Forty albino rats were allocated equally to four groups. C-group received corn oil. RO-group received RO orally. MA-group received MA. MA-RO-group received RO in addition to MA. After three weeks the lungs were dissected for histopathological and biochemical investigations. MA-group showed manifestations of severe inflammation with inflammatory cells infiltration in the lung. MA-RO-group showed limited inflammatory cell infiltration. C-group and RO-group appeared with weak anti-survivin immunoreactivity. MA-group showed strong positive immunoreactivity. The reactivity was weakly positive in MA-RO-group. MA-group showed a significant decrease in SP-D gene expression in comparison to the C-group, in addition, MA-RO-group showed a significant increase in SP-D expression. In conclusion, the current study approves that oral administration of MA causes lung injury as it has inflammatory effects, caused by oxidative stress and reports the potential of RO to protect lung tissue against toxic effects of MA through its anti-inflammatory, antioxidant, and anti-apoptotic potential.