Allicin Improves Intestinal Epithelial Barrier Function and Prevents LPS-Induced Barrier Damages of Intestinal Epithelial Cell Monolayers

Selenomethionine and Allicin Synergistically Mitigate Intestinal Oxidative Injury by Activating the Nrf2 Pathway

Oxidative stress frequently contributes to intestinal barrier injury in animals and humans. It was reported that both Selenomethionine (SeMet) and allicin exhibit protective effects against a range of diseases caused by oxidative stress. This study aimed to investigate the synergistic antioxidant effects and underlying mechanisms of SeMet and allicin on a H2O2-induced intestinal barrier injury model using IPEC-J2 cells and mice. The results showed that H2O2 induced severe oxidative stress, including a decrease in cell viability, antioxidant level, migration capacity, and cell integrity. SeMet and allicin exhibited significant synergistic anti-oxidative effects on intestinal epithelial cells. The combined use of SeMet and allicin increased SOD activity, GSH content, and GSH/GSSG ratio while decreasing MDA, NO, and ROS content levels. Furthermore, we found that SeMet and allicin synergistically activated the nuclear factor erythroid-related factor 2 (Nrf2)-NAD(P)H dehydrogenase [quinone] 1 (NQO1) signaling pathway and down-regulated endoplasmic reticulum stress (ER stress)-related proteins. However, the synergistic antioxidative and intestinal barrier protective effects of SeMet and allicin were abolished by Nrf2 inhibitor ML385 in vitro and in vivo. In conclusion, SeMet and allicin synergistically attenuate intestinal barrier injury induced by excessively oxidative stress through the activation of the Nrf2 signaling pathway and inhibition ER stress. These findings support that the combined use of SeMet and allicin could enhance antioxidative properties and alleviate intestinal injury in further clinical practice.

Cellular uptake of allicin in the hCMEC/D3 human brain endothelial cells: exploring blood-brain barrier penetration in an in vitro model

Background

Allicin, a bioactive compound derived from garlic (Allium sativum), demonstrates antibacterial activity against a broad spectrum of bacteria including the most common meningitis pathogens. In order to advocate for allicin as a potential therapeutic candidate for bacterial meningitis, the present study aimed to assess the ability of allicin to cross the blood-brain barrier (BBB) using an in vitro model.

Methods

The cell viability of the human brain endothelial cell line hCMEC/D3 after incubation with various concentrations of allicin was investigated using an MTT assay at 3 and 24 h. Additionally, reactive oxygen species (ROS) production of allicin-treated hCMEC/D3 cells was examined at 3 h. The concentrations of allicin that were not toxic to the cells, as determined by the MTT assay, and did not significantly increase ROS generation, were then used to investigate allicin's ability to traverse the in vitro BBB model for 3 h. High-performance liquid chromatography (HPLC) analysis was utilized to examine the allicin concentration capable of passing the in vitro BBB model. The cellular uptake experiments were subsequently performed to observe the uptake of allicin into hCMEC/D3 cells. The pkCSM online tool was used to predict the absorption, distribution, metabolism, excretion, and pharmacokinetic properties of allicin and S-allylmercaptoglutathione (GSSA).

Results

The results from MTT assay indicated that the highest non-toxicity concentration of allicin on hCMEC/D3 cells was 5 µg/ml at 3 h and 2 µg/ml at 24 h. Allicin significantly enhanced ROS production of hCMEC/D3 cells at 10 µg/ml at 3 h. After applying the non-toxicity concentrations of allicin (0.5-5 µg/ml) to the in vitro BBB model for 3 h, allicin was not detectable in both apical and basolateral chambers in the presence of hCMEC/D3 cells. On the contrary, allicin was detected in both chambers in the absence of the cells. The results from cellular uptake experiments at 3 h revealed that hCMEC/D3 cells at 1 × 104 cells could uptake allicin at concentrations of 0.5, 1, and 2 µg/ml. Moreover, allicin uptake of hCMEC/D3 cells was proportional to the cell number, and the cells at 5 × 104 could completely uptake allicin at a concentration of 5 µg/ml within 0.5 h. The topological polar surface area (TPSA) predicting for allicin was determined to be 62.082 Å2, indicating its potential ability to cross the BBB. Additionally, the calculated logBB value surpassing 0.3 suggests that the compound may exhibit ease of penetration through the BBB.

Conclusion

The present results suggested that allicin was rapidly taken up by hCMEC/D3 cells in vitro BBB model. The prediction results of allicin's distribution patterns suggested that the compound possesses the capability to enter the brain.

Bacillus amyloliquefaciens SC06 Relieving Intestinal Inflammation by Modulating Intestinal Stem Cells Proliferation and Differentiation via AhR/STAT3 Pathway in LPS-Challenged Piglets

Bacillus amyloliquefaciens is a well-accepted probiotic, with many benefits for both humans and animals. The ability of intestinal stem cells (ISCs) to develop into several intestinal epithelial cell types helps accelerate intestinal epithelial regeneration. Limited knowledge exists on how bacteria regulated ISCs proliferation and regeneration. Our study investigated the effects of Bacillus amyloliquefaciens supplementation on ISC proliferation and regeneration and intestinal mucosal barrier functions in piglets exposed to lipopolysaccharide (LPS). Eighteen piglets (male, 21 days old) were randomly split into 3 clusters: CON cluster, LPS cluster, and SC06+LPS cluster. On day 21, 100 μg/kg body weight of LPS was intraperitoneally administered to the SC06+LPS and LPS groups. We found SC06 supplementation maintained the intestinal barrier integrity, enhanced intestinal antioxidant capacity, reduced generation of inflammatory response, and suppressed enterocyte apoptosis against the deleterious effects triggered by LPS. In addition, our research indicated that the SC06 supplementation not only improved the ISC regeneration, but also resulted in upregulation of aryl hydrocarbon receptor (AhR) in LPS-challenge piglets. Further studies showed that SC06 also induced ISC differentiation toward goblet cells and inhibited their differentiation to intestinal absorptive cells and enterocytes. The coculture system of SC06 and ileum organoids revealed that SC06 increased the growth of ISCs and repaired LPS-induced organoid damage through activating the AhR/STAT3 signaling pathway. These findings showed that SC06, possibly through the AhR/STAT3 pathway, accelerated ISC proliferation and promoted epithelial barrier healing, providing a potential clinical treatment for IBD. Our research demonstrated that SC06 is effective in preventing intestinal epithelial damage after pathological injury, restoring intestinal homeostasis, and maintaining intestinal epithelial regeneration.

Regulation Mechanism and Potential Value of Active Substances in Spices in Alcohol-Liver-Intestine Axis Health

Excessive alcohol intake will aggravate the health risk between the liver and intestine and affect the multi-directional information exchange of metabolites between host cells and microbial communities. Because of the side effects of clinical drugs, people tend to explore the intervention value of natural drugs on diseases. As a flavor substance, spices have been proven to have medicinal value, but they are still rare in treating hepatointestinal diseases caused by alcohol. This paper summarized the metabolic transformation of alcohol in the liver and intestine and summarized the potential value of various perfume active substances in improving liver and intestine diseases caused by alcohol. It is also found that bioactive substances in spices can exert antioxidant activity in the liver and intestine environment and reduce the oxidative stress caused by diseases. These substances can interfere with fatty acid synthesis, promote sugar and lipid metabolism, and reduce liver injury caused by steatosis. They can effectively regulate the balance of intestinal flora, promote the production of SCFAs, and restore the intestinal microenvironment.

Development of Intestinal Injury and Restoration of Weaned Piglets under Chronic Immune Stress

This study aimed to investigate the effects of lipopolysaccharide (LPS)-induced chronic immune stress on intestinal morphology and function, immune system, oxidative status, and mitochondrial function in piglets. Fifty healthy Duroc × Landrace × Yorkshire piglets (21 ± 2 days old, barrow, 6.98 ± 0.14 kg body weight) were selected and randomly allotted to five groups, which were slaughtered at 0 (0 group), 1, 5, 9, and 15 d of LPS injection. The results showed that compared with the piglets without LPS injection, LPS injection significantly impaired the intestinal morphology and permeability at 1, 5, and 9 d, as manifested by the increased serum lactic acid and decreased ratio of villus height to crypt depth (p < 0.05). Moreover, intestinal inflammation and oxidative and mitochondrial injury were caused at 1 d, as manifested by upregulated IL-6 mRNA expression, increased malondialdehyde content, and impaired mitochondrial morphology (p < 0.05). However, these parameters were restored to levels identical to 0 group at 9~15 d, accompanied by significantly increased antioxidant capacity, enhanced protein expression of CD3+ and CD68+, and upregulated mRNA abundance of genes related to mitochondrial biogenesis and functions (p < 0.05). Collectively, these results suggest that the intestinal injury of piglets caused by chronic immune stress could be self-repaired.

Qige Huxin Formula Attenuates Isoprenaline-Induced Cardiac Fibrosis in Mice via Modulating Gut Microbiota and Protecting Intestinal Integrity

Background

The composition and metabolic activities of gut microbiota are strongly interconnected with cardiac fibrosis (CF) and heart failure (HF). Qige Huxin formula (QHF), a traditional Chinese medicine (TCM) formulation originating from a classical Fangji Huangqi decoction, has been widely used to clinically treat HF for decades. However, it is still unclear whether QHF alleviates CF by modulating gut microbiota and intestinal integrity.

Purpose

This study aimed to investigate the cardioprotective effects of QHF in isoprenaline-induced CF through modulating gut microbiota and intestinal integrity.

Methods

Fifty mice were randomly divided into five groups after one week of acclimatization feeding: control group, model group, 2.56 g/kg/d group (low-dose QHF), 5.12 g/kg/d group (high-dose QHF), and meto group (15 mg/kg/d). The CF model was established by subcutaneously injecting the mice with isoprenaline (10 mg/kg/d for 14 days), followed by QHF treatment. The heart volume, cardiac weight index (CWI), serum myocardial enzymes, serum inflammatory cytokines, serum lipopolysaccharide, histopathology of the heart and colon tissues, ZO-1, and occludin of colon tissues were then measured. Fecal samples from mice were analyzed using 16S rRNA sequencing.

Results

QHF treatment significantly reduced heart volume, CWI, and serum CK and CK-MB levels, attenuated cardiac histopathological alterations, and alleviated CF. QHF treatment also downregulated TNF-α, IL-1β, and IL-6 in serum. Moreover, QHF treatment decreased the serum level of lipopolysaccharide and maintained intestinal integrity by upregulating ZO-1 and occludin. The 16S rRNA microbiota analysis revealed that QHF treatment increased the relative abundance of Marvinbryantia and Phascolarctobacterium.

Conclusions

QHF treatment exerts cardioprotective effects through modulating gut microbiota, protecting intestinal integrity, and alleviating inflammation. This study shows that gut microbiota may enhance heart-gut interaction.

Allicin in Digestive System Cancer: From Biological Effects to Clinical Treatment

Allicin is the main active ingredient in freshly-crushed garlic and some other allium plants, and its anticancer effect on cancers of digestive system has been confirmed in many studies. The aim of this review is to summarize epidemiological studies and in vitro and in vivo investigations on the anticancer effects of allicin and its secondary metabolites, as well as their biological functions. In epidemiological studies of esophageal cancer, liver cancer, pancreatic cancer, and biliary tract cancer, the anticancer effect of garlic has been confirmed consistently. However, the results obtained from epidemiological studies in gastric cancer and colon cancer are inconsistent. In vitro studies demonstrated that allicin and its secondary metabolites play an antitumor role by inhibiting tumor cell proliferation, inducing apoptosis, controlling tumor invasion and metastasis, decreasing angiogenesis, suppressing Helicobacter pylori, enhancing the efficacy of chemotherapeutic drugs, and reducing the damage caused by chemotherapeutic drugs. In vivo studies further demonstrate that allicin and its secondary metabolites inhibit cancers of the digestive system. This review describes the mechanisms against cancers of digestive system and therapeutic potential of allicin and its secondary metabolites.