Preventive Effect of Garlic Oil and Its Organosulfur Component Diallyl-Disulfide on Cigarette Smoke-Induced Airway Inflammation in Mice

Effect of Honey and Aqueous Garlic Extracts against Short-Term Exposure of Cigarette Tobacco Smoking in Mice: Histopathological and Biochemical Investigations

It is well known that cigarette smoking adversely affects human health and induces oxidative stress in most vital organs. This study aims to assess the biochemical, histological, and ultrastructural values of honey and garlic extracts in ameliorating the effects of short-term exposure to cigarette smoke in mice. Forty-eight mice were randomly divided into six equal groups: group I was exposed to fresh air only, group II was exposed to cigarette smoke, group III was given 0.2 ml of honey extract, group IV was exposed to cigarette smoke and was given 0.2 ml of honey extract, group V was given 0.2 ml of garlic extract, and group VI was exposed to cigarette smoke and was given 0.2 ml of aqueous garlic extract. These exposures were repeated daily for 21 consecutive days among the treated groups. By the end of the third week, the animals were euthanized by physical cervical dislocation. Blood was taken for biochemical study, and the selected organs of the liver, kidney, and jejunum were processed for histological and ultrastructural studies. The biochemical results showed that short-term exposure of experimental mice to cigarette smoking did not alter the liver function tests except for decreasing the albumin level. Moreover, cigarette smoking elevates the concentration of carbonyl protein content and cystatin C. Histologically, the use of honey and garlic showed good protection to the liver, kidney, and jejunum, which was proved by transmission electron microscopy, in addition to lowering the oxidative stress biomarkers. In conclusion, using honey and/or garlic helps protect the liver, kidney, and jejunum against the hazardous effects of cigarette smoke.

Diallyl disulfide attenuates pyroptosis via NLRP3/Caspase-1/IL-1β signaling pathway to exert a protective effect on hypoxic-ischemic brain damage in neonatal rats

Hypoxic-ischemic encephalopathy (HIE) is a perinatal brain disease caused by hypoxia in neonates. It is one of the leading causes of neonatal death in the perinatal period, as well as disability beyond the neonatal period. Due to the lack of a unified and comprehensive treatment strategy for HIE, research into its pathogenesis is essential. Diallyl disulfide (DADS) is an allicin extract, with detoxifying, antibacterial, and cardiovascular disease protective effects. This study aimed to determine whether DADS can alleviate HIE induced brain damage in rats and oxygen-glucose deprivation (OGD)-induced pyroptosis in PC12 cells, as well as whether it can inhibit pyroptosis via the NLRP3/Caspase-1/IL-1β signaling pathway. In vivo, DADS significantly reduced the cerebral infarction volume, alleviated inflammatory reaction, reduced astrocyte activation, promoted tissue structure recovery, improved pyroptosis caused by HIE and improved the prognosis following HI injury. In vitro findings indicated that DADS increased cell activity, decreased LDH activity and reduced the expression of pyroptosis-related proteins, including IL-1β, IL-18, and certain inflammatory factors in PC12 cells caused by OGD. Mechanistically, DADS inhibited pyroptosis and protected against HIE via the NLRP3/Caspase-1/IL-1β pathway. The specific inhibitor of caspase-1, VX-765, inhibited caspase-1 activation, and IL-1β expression was determined. Additionally, the overexpression of NLRP3 reversed the protective effect of allicin against OGD-induced pyroptosis. In conclusion, these findings demonstrated that DADS inhibits the NLRP3/Caspase-1/IL-1β signaling pathway and decreases HI brain damage.

The Potential of Natural Oils to Improve Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory disorder that includes ulcerative colitis (UC) and Crohn's disease (CD), the exact cause of which is still unknown. Numerous studies have confirmed that diet is one of the major environmental factors associated with IBD, as it can regulate the gut microbiota and reduce inflammation and oxidative stress. Since the consumption of oil is essential in the diet, improving IBD through oil has potential. In this article, we first briefly reviewed the current treatment methods for IBD and introduce the role of natural oils in improving inflammatory diseases. We then focused on the recent discovery of the role of natural oils in the prevention and treatment of IBD and summarized their main mechanisms of action. The results showed that the anti-inflammatory activity of oils derived from different plants and animals has been validated in various experimental animal models. These oils are capable of improving the intestinal homeostasis in IBD animal models through multiple mechanisms, including modulation of the gut microbiota, protection of the intestinal barrier, reduction in colonic inflammation, improvement in oxidative stress levels in the intestine, and regulation of immune homeostasis. Therefore, dietary or topical use of natural oils may have potential therapeutic effects on IBD. However, currently, only a few clinical trials support the aforementioned conclusions. This review emphasized the positive effects of natural oils on IBD and encouraged more clinical trials to provide more reliable evidence on the improvement of human IBD by natural oils as functional substances.

Biological properties and therapeutic applications of garlic and its components

Garlic is one of the most widely employed condiments in cooking. It has also been used since ancient times in traditional plant-based medicine, largely based on its organosulfur compounds. The objective of this study was to provide updated information on the biological and therapeutic garlic properties. Garlic has been found to possess important biological properties with high therapeutic potential, which is influenced by the mode of its utilization, preparation, and extraction. It has been attributed with antioxidant, anti-inflammatory, and immunomodulatory capacities. Garlic, in particular its organosulfur compounds, can maintain immune system homeostasis through positive effects on immune cells, especially by regulating cytokine proliferation and expression. This may underlie their usefulness in the treatment of infectious and tumor processes. These compounds can also offer vascular benefits by regulating lipid metabolism or by exerting antihypertensive and antiaggregant effects. However, further clinical trials are warranted to confirm the therapeutic potential of garlic and its derivatives.

Allicin supressed Escherichia coli-induced urinary tract infections by a Novel MALT1/NF-κB pathway

Escherichia coli (E. coli) strains cause the majority of urinary tract infections (UTIs) and are resistant to various antibiotics. Therefore, it is imperative to explore novel host-target therapies. As a...

An exploratory review of Potential Adjunct Therapies for the Treatment of Coronavirus Infections

Objective

The purpose of this exploratory review c, including vitamin D, zinc, vitamin A, elderberry (S nigra), garlic (A sativum), licorice (G glabra), stinging nettle (U dioica), N-acetylcysteine, quercetin and selenium as potential adjunct therapies for the treatment of coronavirus infections.

Methods

A search of PubMed was performed for articles published from 2005 to 2021. Key words searched were zinc, vitamin A, vitamin D, Sambucus nigra, Allium sativum, Glycyrrhiza glabra, Urtica dioica, N-Acetylcysteine, quercetin, selenium and coronavirus.

Results

There were 47 articles selected for this review. Findings included that vitamin D, zinc, vitamin A, S nigra, A sativum, G glabra, U dioica, N-acetylcysteine, quercetin and selenium have been shown to produce anti-inflammatory, immunostimulatory or antiviral effects that may enhance the actions of standard therapeutics for the treatment of CoV infections. We found only research articles related to the effects of vitamin D, zinc, G glabra, quercetin and selenium against COVID-19.

Conclusion

We identified non-pharmaceutical supplements (Vitamin D, zinc, vitamin A, S nigra, A sativum, G glabra and U dioica) which may have potential to provide support for those with coronavirus infections. However, rigorous clinical studies need to be performed before any clinical recommendations can be made at this time.

Diallyl disulfide prevents cigarette smoke-induced emphysema in mice

INTRODUCTION

Cigarette smoke (CS) is the main risk factor for the development of chronic obstructive pulmonary disease (COPD) and pulmonary emphysema. The use of antioxidants has emerged as a potential therapeutic strategy to treat airway inflammation and lung diseases. In the current study, we investigated the potential therapeutic impact of diallyl disulfide (Dads) treatment in a murine model of CS-induced emphysema.

METHODS

C57BL/6 mice were exposed to CS for 60 consecutive days and treated with vehicle or Dads (30, 60 or 90 mg/kg) by oral gavage for the last 30 days, three times/week. The control group was sham-smoked and received vehicle treatment. All mice were euthanized 24 h after day 60; bronchoalveolar lavage (BAL) was performed and lungs were processed for further experimentation. Histological (HE stained sections, assessment of mean linear intercept (Lm)), biochemical (nitrite, superoxide dismutase (SOD), glutathione transferase (GST), and malondialdehyde (MDA) equivalents), and molecular biology (metalloproteinase (MMP) 12, SOD2, carbonyl reductase 1 (CBR1), nitrotyrosine (PNK), 4-hydroxynonenal (4-HNE), and CYP2E1) analyses were performed.

RESULTS

Treatment with Dads dose-dependently reduced CS-induced leukocyte infiltration into the airways (based on BAL fluid counts) and improved lung histology (indicated by a reduction of Lm). Furthermore, CS exposure dramatically reduced the activity of the antioxidant enzymes SOD and GST in lung tissue and increased nitrite and MDA levels in BAL; these effects were all effectively counteracted by Dads treatment. Western blot analysis further confirmed the antioxidant potential of Dads, showing that treatment prevented the CS-induced decrease in SOD2 expression and increase in lung damage markers, such as CBR1, PNK, and 4-HNE. Furthermore, increased MMP12 (an important hallmark of CS-induced emphysema) and CYP2E1 lung protein levels were significantly reduced in mice receiving Dads treatment.

CONCLUSION

Our findings demonstrate that treatment with Dads is effective in preventing multiple pathological features of CS-induced emphysema in an in vivo mouse model. In addition, we have identified several proteins/enzymes, including 4-HNE, CBR1, and CYP2E1, that are modifiable by Dads and could represent specific therapeutic targets for the treatment of COPD and emphysema.

A comprehensive understanding about the pharmacological effect of diallyl disulfide other than its anti-carcinogenic activities

Diallyl disulfide (DADS), an oil-soluble sulfur compound that is responsible for the biological effects of garlic, displays numerous biological activities, among which its anti-cancer activities are the most famous ones. In recent years, the pharmacological effects of DADS other than its anti-carcinogenic activities have attracted numerous attentions. For example, it has been reported that DADS can prevent the microglia-mediated neuroinflammatory response and depression-like behaviors in mice. In the cardiovascular system, DADS administration was found to ameliorate the isoproterenol- or streptozotocin-induced cardiac dysfunction via the activation of the nuclear factor E2-related factor 2 (Nrf2) and insulin-like growth factor (IGF)-phosphatidylinositol-3-kinase (PI3K)-protein kinase B (Akt) signaling. DADS administration can also produce neuroprotective effects in animal models of Alzheimer's disease and protect the heart, endothelium, liver, lung, and kidney against cellular or tissue damages induced by various toxic factors, such as the oxidized-low density lipoprotein (ox-LDL), carbon tetrachloride (CCl₄), ethanol, acetaminophen, Cis-Diammine Dichloroplatinum (CisPt), and gentamicin. The major mechanisms of action of DADS in disease prevention and/or treatment include inhibition of inflammation, oxidative stress, and cellular apoptosis. Mechanisms, including the activation of Akt, extracellular signal-regulated kinase 1/2 (ERK1/2), protein kinase A (PKA), and cyclic adenosine monophosphate-response element binding protein (CREB) and the inhibition of histone deacetylases (HDACs), can also mediate the cellular protective effects of DADS in different tissues and organs. In this review, we summarize and discuss the pharmacological effects of DADS other than its anti-carcinogenic activities, aiming to reveal more possibilities for DADS in disease prevention and/or treatment.

Immunomodulatory effect of diallyl sulfide on experimentally-induced benign prostate hyperplasia via the suppression of CD4+T/IL-17 and TGF-β1/ERK pathways

Benign prostatic hyperplasia (BPH) is a nonmalignant enlargement of the prostate common in older men. Diallyl sulfide (DAS), a major component of garlic, has been reported to possess antioxidant, anti-inflammatory, and antiproliferative effects. However, the underlying protective immunomodulatory mechanism of DAS on BPH remains vague. Herein, experimental BPH was induced in rats by daily subcutaneous injection of testosterone propionate (TP) (3 mg/kg, s.c.) for 4 weeks. In parallel, finasteride (Fin) (5 mg/kg, p.o) or DAS (50 mg/kg, p.o.) was administered orally during BPH induction. TP-induced histological alterations and the immune-inflammatory cascade. On the other hand, DAS or Fin administration alleviated all abnormalities induced testosterone. Fin and DAS administration markedly reduced prostate weight by 53% with Fin, and by 60% with DAS. Moreover, serum testosterone and DHT were reduced by 55% and 52%, respectively, with Fin and by 68% and 75%, respectively, with DAS, in concordance with decreased protein expression of androgen receptor (AR), and prostate-specific antigen (PSA). Furthermore, both regime lessen immune-inflammatory milieu, as evidenced by decrease CD4+ T-cells protein expression and associated inflammatory cytokines. Concomitantly, Fin and DAS exhibited marked mitigation in insulin-like growth factor-1 (IGF-1), transforming growth factor-beta1 (TGF-β1), and phosphorylated extracellular signal-regulated kinase (ERK1/2) signaling. Besides alleviating oxidative stress by 53% and 68% in prostatic MDA and by 27% and 7% in prostatic iNOS with Fin and DAS, respectively. In conclusion, this work highlighted a potential therapeutic approach of DAS as a dietary preventive agent against BPH via its anti-inflammatory and immunomodulatory effect along with suppression of the ERK pathway.

Diallyl Disulfide Suppresses Inflammatory and Oxidative Machineries following Carrageenan Injection-Induced Paw Edema in Mice

Diallyl disulfide (DADS) is the major organosulfur constituent in garlic, with a variety of pharmacological activities including antioxidant and anti-inflammatory. Here, we examined the potential antiedematous impact of DADS- versus carrageenan-mediated paw edema in mice. Carrageenan injection potentiated an inflammatory reaction as presented by the elevated serological C-reactive protein (CRP) levels and transcription of tumor necrosis factor-alpha (TNF-α, Tnfα), interleukin-1 beta (IL-1β, Il1b), interleukin-2 (IL-2, Il2), inducible nitric oxide synthase (iNOS), nitric oxide (NO), cyclooxygenase-2 (COX-2, Ptgs2), prostaglandin E2 (PGE2), monocyte chemoattractant protein-1 (MCP-1, Ccl1), nuclear factor kappa B (NF-κB), and myeloperoxidase (MPO) activity, while interleukin-10 (IL-10) was declined in the injured paw tissue. Additionally, carrageenan elevated lipid peroxidation in terms of malondialdehyde (MDA) and decreased glutathione content (GSH). Remarkably, DADS was found to inhibit the inflammatory signaling, suppressed the developed oxidative damage, and protected the histopathological alterations in the inflamed paw tissue in response to carrageenan injection. Our findings suggest that DADS could be used as an alternative therapy used to alleviate the pathophysiological changes associated with the genesis of paw edema through its potent anti-inflammatory and antioxidant impacts.

Ginsenoside Rg1 protects against cigarette smoke-induced airway remodeling by suppressing the TGF-β1/Smad3 signaling pathway

Chronic obstructive pulmonary disease (COPD) is a devastating and common respiratory disease characterized by chronic inflammation and progressive airway remodeling. Ginsenoside Rg1 (GRg1), a major active component of Panax ginseng, has been found to possess beneficial properties against acute lung injury and respiratory diseases. However, the effects of GRg1 on airway remodeling in COPD remain unclear. In this study, we aimed to investigate the potential protective effects of GRg1 on airway remodeling induced by cigarette smoke (CS) and the underlying mechanism. A rat model of COPD was established in which the animals were subjected to CS and GRg1 daily for 12 weeks. Subsequently, we evaluated lung function, inflammatory responses, along with airway remodeling and associated signaling factors. GRg1 treatment was found to improve pulmonary function, reduce airway collagen volume fraction, and markedly reduce the expression of IL-6, TNF-α, α-SMA, and collagen I. Moreover, GRg1 treatment decreased the expression of TGF-β1, TGF-βR1, and phosphorylated-Smad3. In vitro, pretreatment of MRC5 human lung fibroblasts with GRg1 prior to exposure to cigarette smoke extract (CSE) reversed the cell ultrastructure disorder, decreased the expression of IL-6 and TNF-α, and significantly attenuated transdifferentiation of MRC5 cells by suppressing α-SMA and collagen I expression. Additionally, GRg1 suppressed the TGF-β1/Smad3 signaling pathway in CSE-stimulated MRC5 cells, whereas Smad3 over-expression abolished the anti-transdifferentiation effect of GRg1. In conclusion, the results of our study demonstrated that GRg1 improves lung function and protects against CS-induced airway remodeling, in part by down-regulating the TGF-β1/Smad3 signaling pathway.

Scrophularia buergeriana attenuates allergic inflammation by reducing NF-κB activation

BACKGROUND

Scrophularia buergeriana Miq. (Scrophulariaceae) (SB) has been used as an oriental medicine for the treatment of inflammatory diseases, such as neuritis and pharyngolaryngitis.

PURPOSE

We explored the therapeutic effects of S. buergeriana ethanol extract (SBE) on airway inflammation in ovalbumin (OVA)-induced asthmatic mice and lipopolysaccharide (LPS)-stimulated RAW264.7 cells.

METHODS

Mice were intraperitoneally injected with OVA on days 0 and 14 to elevate the immune response. On days 21 to 23, the mice were challenged with OVA solution and SBE (20 and 40 mg/kg) was administered daily by oral gavage from days 18 to 23. RAW264.7 cells were pretreated with SBE 1 h before LPS stimulation.

RESULTS

SBE administration effectively suppressed inflammatory cell infiltration, the expression of interleukin (IL)-5, IL-13, and IL-17, immunoglobulin E, and airway hyperresponsiveness in an OVA-induced allergic asthma model. A reduction in histological alterations, including airway inflammation and mucus hypersecretion, was observed. These effects of SBE were accompanied by a decrease in matrix metalloproteinase-9 (MMP-9) expression and nuclear factor kappa B (NF-κB) phosphorylation. These responses were observed in LPS-stimulated RAW264.7 cells. SBE treatment reduced the mRNA expression of tumor necrosis factor (TNF)-α, IL-6, and MMP-9, and NF-κB phosphorylation, in LPS-stimulated RAW264.7 cells.

CONCLUSION

Our results indicated that SBE effectively attenuated airway inflammation in an OVA-induced allergic asthma model. These properties of SBE were thought to be involved in the suppression of NF-κB phosphorylation, suggesting that the material has the potential to regulate the development of allergic asthma.

Fatty liver and alteration of the gut microbiome induced by diallyl disulfide

Diallyl disulfide (DADS) is one of the primary components of garlic and it exhibits a broad range of biological activities. In the present study, the effects of DADS on lipid metabolism and its potential role in the modulation of the gut microbiome were determined. Hematoxylin and eosin and oil-red O staining were used to assess the liver and intestinal tissues of mice treated with DADS. The expression of lipid metabolism-associated genes was measured using reverse transcription-quantitative PCR (RT-qPCR). The effects of DADS on the gut microbiome were measured using 16S recombinant (r)DNA gene analysis. The results revealed that the serum non-esterified free fatty acids, high density lipopro-tein-cholesterol, low density lipoprotein-cholesterol, serum total cholesterol, liver triglyceride and total cholesterol levels of the mice fed with a low-dose of DADS was significantly higher when compared with the control. Hematoxylin and eosin and oil-red O staining demonstrated that DADS induced fatty liver in mice. The results of the RT-qPCR revealed that the expression levels of a number of lipid metabolism-associated genes were altered in the livers of mice treated with DADS.

The 16S rDNA gene analysis demonstrated that the mice fed on a normal diet treated with a low-dose of DADS had decreased levels of bacteria from the Bacteroidetes phyla and increased levels of bacteria from the Firmicutes phyla. The Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed the top 20 pathways enriched in the low-dose DADS group of mice fed with a normal diet. In the present study, low-dose DADS induced fatty liver and altered the gut micro-biota, similar to the phenotype induced by a high fat diet, by regulating the expression of lipid metabolism associated genes.