Cysteine-binding adjuvant enhances survival and promotes immune function in a murine model of acute myeloid leukemia.

ABSTRACT: Therapeutic vaccination has long been a promising avenue for cancer immunotherapy but is often limited by tumor heterogeneity. The genetic and molecular diversity between patients often results in variation in the antigens present on cancer cell surfaces. As a result, recent research has focused on personalized cancer vaccines. Although promising, this strategy suffers from time-consuming production, high cost, inaccessibility, and targeting of a limited number of tumor antigens. Instead, we explore an antigen-agnostic polymeric in situ cancer vaccination platform for treating blood malignancies, in our model here with acute myeloid leukemia (AML). Rather than immunizing against specific antigens or targeting adjuvant to specific cell-surface markers, this platform leverages a characteristic metabolic and enzymatic dysregulation in cancer cells that produces an excess of free cysteine thiols on their surfaces. These thiols increase in abundance after treatment with cytotoxic agents such as cytarabine, the current standard of care in AML. The resulting free thiols can undergo efficient disulfide exchange with pyridyl disulfide (PDS) moieties on our construct and allow for in situ covalent attachment to cancer cell surfaces and debris. PDS-functionalized monomers are incorporated into a statistical copolymer with pendant mannose groups and TLR7 agonists to target covalently linked antigen and adjuvant to antigen-presenting cells in the liver and spleen after IV administration. There, the compound initiates an anticancer immune response, including T-cell activation and antibody generation, ultimately prolonging survival in cancer-bearing mice.

Photoinduced Electron Transfer-Based Glutathione-Sensing Theranostic Nanoprodrug with Self-Tracking and Real-Time Drug Release Monitoring for Cancer Treatment.

The rapid development of nanomedicine has considerably advanced precision therapy for cancer treatment. Superior to traditional chemotherapy, emerging theranostic nanoprodrugs can effectively realize inherent self-tracking, targeted drug delivery, stimuli-triggered drug release, and reduced systemic toxicity of chemotherapeutic drugs. However, theranostic nanoprodrugs with real-time drug release monitoring have remained rare so far. In this work, we developed a new glutathione-responsive theranostic nanoprodrug with a high drug-loading content of 59.4 wt % and an average nanoscale size of 46 nm, consisting of the anticancer drug paclitaxel and a fluorescent imaging probe with a high fluorescence quantum yield, which are linked by a disulfide-based glutathione-sensitive self-immolating linker. The strong fluorescence emission of the fluorophore enables efficacious self-tracking and sensitive fluorescence "ON-OFF" glutathione sensing. Upon encountering high-level glutathione in cancer cells, the disulfide bond is cleaved, and the resulting linker halves spontaneously collapse into cyclic small molecules at the same pace, leading to the simultaneous release of the therapeutic drug and the fluorescence-OFF imaging probe. Thereby, the drug release process is efficiently monitored by the fluorescence change in the nanoprodrug. The nanoprodrugs exerted high cytotoxicity toward various cancer cells, especially for A549 and HEK-293 cells, in which the nanoprodrugs generated better therapeutic effects than free paclitaxel. Our work demonstrated a new modality of smart theranostic nanoprodrugs for precise cancer therapy.

Self-Assembly of Cysteine into Nanofibrils Precedes Cystine Crystal Formation: Implications for Aggregation Inhibition.

The self-association of metabolites into well-ordered assemblies at the nanoscale has significant biological and medical implications. The thiol-containing amino acid cysteine (CYS) can assemble into amyloid-like nanofibrils, and its oxidized form, the disulfide-bonded cystine (CTE), forms hexagonal crystals as those found in cystinuria due to metabolic disorder. Yet, there have been no attempts to connect these two phenomena, especially the fibril-to-crystal transition. Here, we reveal that these are not separated events, and the CYS-forming amyloid fibrils are mechanistically linked to hexagonal CTE crystals. For the first time, we demonstrated that cysteine fibrils are a prerequisite for forming cystine crystals, as observed experimentally. To further understand this mechanism, we studied the effects of thiol-containing cystinuria drugs (tiopronin, TIO; and d-penicillamine, PEN) and the canonical epigallocatechin gallate (EGCG) amyloid inhibitor on fibril formation by CYS. The thiol-containing drugs do not solely interact with monomeric CYS via disulfide bond formation but can disrupt amyloid formation by targeting CYS oligomers. On the other hand, EGCG forms inhibitor-dominant complexes (more than one EGCG molecule per cysteine unit) to prevent CYS fibril formation. Interestingly, while CYS can be oxidized into CTE, the thiol drugs can reduce CTE back to CYS. We thus suggest that the formation of crystals in cystinuria could be halted at the initial stage by targeting CYS fibril formation as an alternative to solubilizing the water-insoluble hexagonal CTE crystals at a later stage. Taken together, we depicted a complex hierarchical organization in a simple amino acid assembly with implications for therapeutic intervention.

Allicin Alleviated LPS-Induced Mastitis via the TLR4/NF-κB Signaling Pathway in Bovine Mammary Epithelial Cells.

Dairy farming is the most important economic activity in animal husbandry. Mastitis is the most common disease in dairy cattle and has a significant impact on milk quality and yield. The natural extract allicin, which is the main active ingredient of the sulfur-containing organic compounds in garlic, has anti-inflammatory, anticancer, antioxidant, and antibacterial properties; however, the specific mechanism underlying its effect on mastitis in dairy cows needs to be determined. Therefore, in this study, whether allicin can reduce lipopolysaccharide (LPS)-induced inflammation in the mammary epithelium of dairy cows was investigated. A cellular model of mammary inflammation was established by pretreating bovine mammary epithelial cells (MAC-T) with 10 µg/mL LPS, and the cultures were then treated with varying concentrations of allicin (0, 1, 2.5, 5, and 7.5 µM) added to the culture medium. MAC-T cells were examined using RT-qPCR and Western blotting to determine the effect of allicin. Subsequently, the level of phosphorylated nuclear factor kappa-B (NF-κB) was measured to further explore the mechanism underlying the effect of allicin on bovine mammary epithelial cell inflammation. Treatment with 2.5 µM allicin considerably decreased the LPS-induced increase in the levels of the inflammatory cytokines interleukin-1ß (IL-1ß), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor-α (TNF-α) and inhibited activation of the NOD-like receptor protein 3 (NLRP3) inflammasome in cow mammary epithelial cells. Further research revealed that allicin also inhibited the phosphorylation of inhibitors of nuclear factor kappa-B-α (IκB-α) and NF-κB p65. In mice, LPS-induced mastitis was also ameliorated by allicin. Therefore, we hypothesize that allicin alleviated LPS-induced inflammation in the mammary epithelial cells of cows probably by affecting the TLR4/NF-κB signaling pathway. Allicin will likely become an alternative to antibiotics for the treatment of mastitis in cows.

Bioderived Lipoic Acid-Based Dynamic Covalent Nanonetworks of Poly(disulfide)s: Enhanced Encapsulation Stability and Cancer Cell-Selective Delivery of Drugs.

Dynamic covalent poly(disulfide)-based cross-linked nanoaggregates, termed nanonetworks (NNs), endowed with pH- and redox-responsive degradation features have been fabricated for stable noncovalent encapsulation and triggered cargo release in a controlled fashion. A bioderived lipoic acid-based Gemini surfactant-like amphiphilic molecule was synthesized for the preparation of nanoaggregates. It self-assembles by a entropy-driven self-assembly process in aqueous milieu. To further stabilize the self-assembled nanostructure, the core was cross-linked by ring-opening disulfide exchange polymerization (RODEP) of 1,2-dithiolane rings situated inside the core of the nanoaggregates. The cross-linked nanoaggregates, i.e., nanonetwork, are found to be stable in the presence of blood serum, and also, they maintain the self-assembled structure even below the critical aggregation concentration (CAC) as probed by dynamic light scattering (DLS) experiments. The nanonetwork showed almost 50% reduction in guest leakage compared to that of the nanoaggregates as shown by the release profile in the absence of stimuli, suggesting high encapsulation stability as evidenced by the fluorescence resonance energy transfer (FRET) experiment. The decross-linking of the nanonetwork occurs in response to redox and pH stimuli due to disulfide reduction and ß-thioester hydrolysis, respectively, thus empowering disassembly-mediated controlled cargo release up to ∼87% for 55 h of incubation. The biological evaluation of the doxorubicin (DOX)-loaded nanonetwork revealed environment-specific surface charge modulation-mediated cancer cell-selective cellular uptake and cytotoxicity. The benign nature of the nanonetwork toward normal cells makes the system very promising in targeted drug delivery applications. Thus, the ease of synthesis, nanonetwork fabrication reproducibility, robust stability, triggered drug release in a controlled fashion, and cell-selective cytotoxicity behavior, we believe, will make the system a potential candidate in the development of robust materials for chemotherapeutic applications.

Oxidative stress and the importance of H. pylori eradication in patients with functional dyspepsia.

Background: To investigage the thiol and disulphide levels in Helicobacter pylori-positive patients with non-ulcer dyspepsia and investigate the change in these levels with eradication therapy. Methods: This is a prospective observational study. A total of 320 patients diagnosed with dyspepsia according to Rome IV criteria were included in the study. First, blood samples were drawn from patients to determine their serum thiol and disulphide levels. Endoscopic biopsy was performed on all patients and the biopsy specimens obtained were examined pathologically. Patients positive for H. pylori were administered eradication therapy. Blood samples were drawn from these patients for the second time, and their serum thiol and disulphide levels were measured. The thiol-disulfide levels of the patients who were successful in H. pylori eradication treatment, with those who were not, were compared before and after the treatment. Results: The mean plasma disulphide level decreased significantly from 14.0 ± 6.6 to 10.9 ± 5.9 µmol/L in H. pylori-positive patients that responded to the H. pylori eradication treatment (P = 0.033). On the other hand, there was an insignificant increase in the mean serum thiol level (341.4 ± 30.5 vs. 342.6 ± 29.8 µmol/L; P = 0.273) and an insignificant decrease in the mean serum disulphide level (15.2 ± 2.5 vs. 14.8 ± 2.3 µmol/L; P = 0.163) in H. pylori-positive patients that did not respond to the H. pylori eradication treatment. Conclusion: The inflammation caused by H. pylori shifted the thiol-disulphide equilibrium in the cell redox system towards the direction of disulphide. The study findings suggest that the restoration of the said hemostatic balance with eradication therapy relieved the organism from oxidative stress.

Cellular Mechanisms Underlying the Cardioprotective Role of Allicin on Cardiovascular Diseases.

Cardiovascular diseases (CVDs) are a group of diseases in which the common denominator is the affection of blood vessels, heart tissue, and heart rhythm. The genesis of CVD is complex and multifactorial; therefore, approaches are often based on multidisciplinary management and more than one drug is used to achieve the optimal control of risk factors (dyslipidemia, hypertension, hypertrophy, oxidative stress, endothelial dysfunction, inflammation). In this context, allicin, a sulfur compound naturally derived from garlic, has shown beneficial effects on several cardiovascular risk factors through the modulation of cellular mechanisms and signaling pathways. Effective pharmacological treatments for CVD or its risk factors have not been developed or are unknown in clinical practice. Thus, this work aimed to review the cellular mechanisms through which allicin exerts its therapeutic effects and to show why it could be a therapeutic option for the prevention or treatment of CVD and its risk factors.

Experimental study on thioredoxin redox inhibitor 1-methylpropyl 2-imidazolyl disulfide promoting apoptosis of multiple myeloma cells in vitro and in vivo.

OBJECTIVE:   To explore the in vitro and in vivo experimental study of thioredoxin-1(Trx1) inhibitor 1-methylpropyl 2-imidazolyl disulfide (PX-12) promoting multiple myeloma H929 cell apoptosis, investigate the relationship between the inhibitory effect of PX-12 on H929 cells and reactive oxygen species (ROS). MATERIALS AND METHODS: Inhibition of PX-12 on H929 cells in relation to reactive oxygen species (ROS), cell cycle, and apoptosis were assessed by flow cytometry. ELISA kit, IVIS Imaging, Hematoxylin and eosin (H&E) staining and immunohistochemical staining assessment were applied to assess the anti-myeloma effect in the SCID mice model established by H929EL cells. RESULTS: PX-12 inhibited proliferation of H929 cells performed time and dose dependent style. Furthermore, it significantly induced a G2/M phase arrest of the cell cycle in H929 cells. It also increased intracellular ROS and caspase-3 activity in H929 cells indicating that cells have undergone apoptosis. There was an almost 3-5-fold decrease in tumor viability measured by the Living-Imaging system after 21 and 28 days after PX-12 injection compared with the control group. Importantly, PX-12 caused significant decrease in expression of Kappa chain in vivo assessed by immunohistochemical staining. CONCLUSIONS: The results suggest that PX-12 may be a potential strategy for the treatment of MM, and the inhibition of TRX-1 in the treatment of myeloma deserves further research.

Inhibitors of ERp44, PDIA1, and AGR2 induce disulfide-mediated oligomerization of Death Receptors 4 and 5 and cancer cell death.

Breast cancer mortality remains unacceptably high, indicating a need for safer and more effective therapeutic agents. Disulfide bond Disrupting Agents (DDAs) were previously identified as a novel class of anticancer compounds that selectively kill cancers that overexpress the Epidermal Growth Factor Receptor (EGFR) or its family member HER2. DDAs kill EGFR+ and HER2+ cancer cells via the parallel downregulation of EGFR, HER2, and HER3 and activation/oligomerization of Death Receptors 4 and 5 (DR4/5). However, the mechanisms by which DDAs mediate these effects are unknown. Affinity purification analyses employing biotinylated-DDAs reveal that the Protein Disulfide Isomerase (PDI) family members AGR2, PDIA1, and ERp44 are DDA target proteins. Further analyses demonstrate that shRNA-mediated knockdown of AGR2 and ERp44, or expression of ERp44 mutants, enhance basal DR5 oligomerization. DDA treatment of breast cancer cells disrupts PDIA1 and ERp44 mixed disulfide bonds with their client proteins. Together, the results herein reveal DDAs as the first small molecule, active site inhibitors of AGR2 and ERp44, and demonstrate roles for AGR2 and ERp44 in regulating the activity, stability, and localization of DR4 and DR5, and activation of Caspase 8.

Anticancer potential of allicin: A review.

Phytochemicals have attracted attention in the oncological field because they are biologically friendly and have relevant pharmacological activities. Thanks to the intense and unique spicy aroma, garlic is one of the most used plants for cooking. Its consumption is correlated to health beneficial effects towards several chronic diseases, such as cancer, mainly attributable to allicin, a bioactive sulfur compound stored in different plant parts in a precursor form. The objective of this review is to present and critically discuss the chemistry and biosynthesis of allicin, its pharmacokinetic profile, its anticancer mechanisms and molecular targets, and its selectivity towards tumor cells. The research carried out so far revealed that allicin suppresses the growth of different types of tumors. In particular, it targets many signaling pathways associated with cancer development. Future research directions are also outlined to further characterize this promising natural product.

Current Knowledge about the New Drug Firibastat in Arterial Hypertension.

Hypertension significantly increases the risk of cardiovascular disease. Currently, effective standard pharmacological treatment is available in the form of diuretics, ACE inhibitors, angiotensin II receptor blockers and calcium channel blockers. These all help to decrease blood pressure in hypertensive patients, each with their own mechanism. Recently, firibastat, a new first-in-class antihypertensive drug has been developed. Firibastat is a prodrug that when crossing the blood-brain barrier, is cleaved into two active EC33 molecules. EC33 is the active molecule that inhibits the enzyme aminopeptidase A. Aminopeptidase A converts angiotensin II to angiotensin III. Angiotensin III usually has three central mechanisms that increase blood pressure, so by inhibiting this enzyme activity, a decrease in blood pressure is seen. Firibastat is an antihypertensive drug that affects the brain renin angiotensin system by inhibiting aminopeptidase A. Clinical trials with firibastat have been performed in animals and humans. No severe adverse effects related to firibastat treatment have been reported. Results from studies show that firibastat is generally well tolerated and safe to use in hypertensive patients. The aim of this review is to investigate the current knowledge about firibastat in the treatment of hypertension.

Diallyl Disulfide Attenuates STAT3 and NF-κB Pathway Through PPAR-γ Activation in Cerulein-Induced Acute Pancreatitis and Associated Lung Injury in Mice.

We have previously shown that diallyl disulfide (DADS) protects mice against cerulein-induced acute pancreatitis (AP) and associated lung injury. However, the molecular mechanisms underlying its effect and the components involved have not been studied. We hypothesized that DADS may reduce TNF-α, CSE expression, H2S production, STAT3, and NF-κB activation and induce SOCS3 expression through peroxisome proliferator-activated receptor γ (PPAR-γ) pathway in cerulein-induced mice. Male Swiss mice were treated with hourly intraperitoneal injections of cerulein (50 µg/kg) for 6 h. Diallyl disulfide (200 µg/kg) was administered in the presence or absence of PPAR-γ antagonist GW9662 (0.3 mg/kg) (i.p) 1 h after the induction of AP. Our findings revealed that DADS blocked TNF-α, CSE expression, H2S production, and STAT3, and NF-κB activation was reversed by GW9662. Furthermore, GW9662 abrogated DADS-induced SOCS3 expression. The results show for the first that DADS-induced anti-inflammatory effect in acute pancreatitis is regulated through PPAR-γ.

Allicin induces cell cycle arrest and apoptosis of breast cancer cells in vitro via modulating the p53 pathway.

BACKGROUND: The tumor suppressor protein p53 is a most promising target for the development of anticancer drugs. Allicin (diallylthiosulfinate) is one of the most active components of garlic (Alliium sativum L.) and possesses a variety of health-promoting properties with pharmacological applications. However, whether allicin plays an anti-cancer role against breast cancer cells through the induction of p53-mediated apoptosis remains unknown. METHODS AND RESULTS: In this study, we investigate the anti-breast cancer effect of allicin in vitro by using MCF-7 and MD-MBA-231 cells. We found that allicin reduces cell viability, induces apoptosis and cell cycle arrest in both cells. Allicin activated p53 and caspase 3 expressions in both cells but produced different effects on the expression of p53-related biomarkers. In MDA-MB-231 cells, allicin up-regulated the mRNA and protein expression of A1BG and THBS1 while down-regulated the expression of TPM4. Conversely, the mRNA and protein expression of A1BG, THBS1 and TPM4 were all reduced in MCF-7 cells. Hence, allicin induces cell cycle arrest and apoptosis in breast cancer cells through p53 activation but it effects on the expression of p53-related biomarkers were dependent upon the specific type of breast cancer involved. CONCLUSIONS: These findings suggest that allicin induces apoptosis and regulates biomarker expression in breast cancer cell lines through modulating the p53 signaling pathway. Furthermore, our results promote the utility of allicin as compound for further studies as an anticancer drug targeting p53.

New Drug for Mismatch Repair Deficient Endometrial Cancer and Solid Tumors.

The Food and Drug Administration (FDA) has granted accelerated approval to dostarlimab-gxly (Jemperli) for the treatment of adults with mismatch repair deficient recurrent or advanced endometrial cancer and solid tumors.

Engineering Paclitaxel Prodrug Nanoparticles via Redox-Activatable Linkage and Effective Carriers for Enhanced Chemotherapy.

The current clinical performance of chemotherapy is far from satisfactory, greatly limited by insufficient delivery efficacy and serious systemic side effects. Dimeric prodrug systems are emerging as valuable strategies for boosting the antitumor outcome. Here, dimeric paclitaxel prodrugs were synthesized with different bridged linkers, and the formed prodrug nanoparticles possessed excellent colloidal stability and ultrahigh drug content. The diselenide bond containing paclitaxel prodrugs could respond to a redox-heterogeneous intracellular microenvironment for on-demand drug release and subsequently show a selective cytotoxicity toward tumor cells against normal cells. Furthermore, the optimal carrier materials were screened out according to their contribution on stability, endocytosis, cytotoxicity, biodistribution, and antitumor efficacy. Compared with DSPE-PEG, human serum albumin, and Fe-tannic acid-based complex, F127 anchored dimeric paclitaxel nanoformulations exhibited preferential tumor accumulation and potent anticancer effect. Our present work provides deep insight into the development of advanced nanoformulations with comprehensive advantages for enhancing cancer therapy.

Anti-Inflammatory Effect of Allicin Associated with Fibrosis in Pulmonary Arterial Hypertension.

Pulmonary arterial hypertension (PAH) is characterized by pulmonary vascular remodeling. Recent evidence supports that inflammation plays a key role in triggering and maintaining pulmonary vascular remodeling. Recent studies have shown that garlic extract has protective effects in PAH, but the precise role of allicin, a compound derived from garlic, is unknown. Thus, we used allicin to evaluate its effects on inflammation and fibrosis in PAH. Male Wistar rats were divided into three groups: control (CON), monocrotaline (60 mg/kg) (MCT), and MCT plus allicin (16 mg/kg/oral gavage) (MCT + A). Right ventricle (RV) hypertrophy and pulmonary arterial medial wall thickness were determined. IL-1ß, IL-6, TNF-α, NFκB p65, Iκß, TGF-ß, and α-SMA were determined by Western blot analysis. In addition, TNF-α and TGF-ß were determined by immunohistochemistry, and miR-21-5p and mRNA expressions of Cd68, Bmpr2, and Smad5 were determined by RT-qPCR. Results: Allicin prevented increases in vessel wall thickness due to TNF-α, IL-6, IL-1ß, and Cd68 in the lung. In addition, TGF-ß, α-SMA, and fibrosis were lower in the MCT + A group compared with the MCT group. In the RV, allicin prevented increases in TNF-α, IL-6, and TGF-ß. These observations suggest that, through the modulation of proinflammatory and profibrotic markers in the lung and heart, allicin delays the progression of PAH.

Parasitological and Biochemical Efficacy of the Active Ingredients of Allium sativum and Curcuma longa in Schistosoma mansoni Infected Mice.

The active ingredients allicin and curcumin have a wide range of actions against fungi, bacteria, and helminths. Therefore, the study was aimed to evaluate the efficacy of allicin (AL) and curcumin (CU) as antischistosomal drugs and their biochemical effects in normal and Schistosoma mansoni-infected mice. Praziquantel (PZQ) was administrated for two successive days while AL or CU was given for two weeks from the week 7th postinfection (PI). The possible effect of different regimens on Schistosoma worms was evaluated by measuring the percentage of the recovered worms, tissue egg load, and oogram pattern. Serum alanine transaminase activity and levels of triglycerides, cholesterol, and uric acid were measured. Liver tissue malondialdehyde and reduced glutathione levels besides, the activities of glutathione-S-transferase, superoxide dismutase and catalase were assessed for the oxidative/antioxidant condition. DNA electrophoresis of liver tissue was used to indicate the degree of fragmentation. There was a significant reduction in the recovered worms and egg load, with a marked change of oogram pattern in all treated groups with PZQ, AL, and CU in comparison with infected-untreated mice. PZQ, AL, and CU prevented most of the hematological and biochemical disorders, as well as significantly improved the antioxidant capacity and enhanced DNA fragmentation in the liver tissue of schistosomiasis mice compared to the infected-untreated group. These promising results suggest that AL and CU are efficient as antischistosomal drugs, and it would be beneficial to test their combination to understand the mechanism of action and the proper period of treatment leading to the best result.

Aptamer-PROTAC Conjugates (APCs) for Tumor-Specific Targeting in Breast Cancer.

Development of proteolysis targeting chimeras (PROTACs) is emerging as a promising strategy for targeted protein degradation. However, the drug development using the heterobifunctional PROTAC molecules is generally limited by poor membrane permeability, low in vivo efficacy and indiscriminate distribution. Herein an aptamer-PROTAC conjugation approach was developed as a novel strategy to improve the tumor-specific targeting ability and in vivo antitumor potency of conventional PROTACs. As proof of concept, the first aptamer-PROTAC conjugate (APC) was designed by conjugating a BET-targeting PROTAC to the nucleic acid aptamer AS1411 (AS) via a cleavable linker. Compared with the unmodified BET PROTAC, the designed molecule (APR) showed improved tumor targeting ability in a MCF-7 xenograft model, leading to enhanced in vivo BET degradation and antitumor potency and decreased toxicity. Thus, the APC strategy may pave the way for the design of tumor-specific targeting PROTACs and have broad applications in the development of PROTAC-based drugs.

Diallyl disulfide ameliorates methotrexate-induced nephropathy in rats: Molecular studies and network pharmacology analysis.

Methotrexate (MTX) is a promising chemotherapeutic agent. Its medical use is limited by induced nephropathy. Our study was designed to explore the reno-protective effect of diallyl disulfide (DADS), an organosulfur compound of garlic oil, on MTX-induced nephropathy. Adult rats were randomly divided into 4 groups; normal control, DADS (50 mg kg-1  day-1 , p.o.), MTX (20 mg/kg, i.p.) and DADS+MTX. DADS significantly decreased serum creatinine, urea, uric acid, and albumin levels with an improvement of final body weight. Additionally, DADS markedly attenuated MTX-induced elevations in renal MDA and NO2- contents with an increase in GSH content and SOD activity. Mechanistically, DADS effectively down-regulated mRNA expression level of renal p38 and NF-κB. Additionally, DADS positively regulated the NRF2 gene with a remarkable inhibition of Keap-1 gene. Furthermore, DADS up-regulated BCL2 protein and remarkably suppressed the expression of both BAX and caspase-3 proteins. Overall, DADS has favorable renal protection against MTX-induced nephropathy via modulation of Keap-1/NRF2, p38/NF-κB, and BCL2/BAX/caspase-3 signaling. PRACTICAL APPLICATIONS: Diallyl disulfide is one of the organosulfur compounds of garlic oil. Our study demonstrated that DADS substantially alleviated the decline of kidney function and renal injury induced by MTX. The antioxidative, anti-inflammatory, and anti-apoptotic properties may constitute an important part of its therapeutic applications via regulation of p38/NF-κB, Keap-1/NRF2, and BCL2/BAX/caspase-3 signaling pathways. Therefore, DADS could be a potential therapeutic adjunct in cancer chemotherapy to decrease the associated side effects of MTX. It should be further explored clinically as a protective agent for MTX-treated cancer patients.

Thioacetamide-induced acute hepatic encephalopathy: central vs peripheral effect of Allicin.

Hepatic encephalopathy (HE) is a debilitating and life-threatening disease. Results from acute or chronic liver failure and is characterized by abnormal cerebral and neurological alterations. This study aimed at investigating the effect of allicin, the major functional component in freshly crushed garlic extract, on thioacetamide (TAA)-induced HE in rats. Induction of HE by a single dose of TAA (300 mg/kg; I.P.) was associated with a marked elevation in the serum levels of alanine aminotransferase, aspartate aminotransferase, bilirubin, albumin, total protein, blood urea nitrogen and serum ammonia besides reduction in the serum level of albumin. Moreover, it was accompanied with an increase in the hepatic and brain levels of inflammatory mediators; TNF-α and IL-1ß as well as elevation of the hepatic and brain levels of oxidative stress biomarkers; reduced glutathione and lipid peroxidation evidenced by malondialdeyde. Oral administration of allicin (50, 100 and 200 mg/kg; P.O.) for 6 days prior to TAA injection restored the serum liver function, hepatic and brain levels of inflammatory mediators as well as oxidative stress biomarkers in a dose-dependent manner. From our results, it can be concluded that allicin has a protective effect on TAA-induced HE in rats in a dose-dependent manner due to its powerful antioxidant and anti-inflammatory properties.