The antioxidant mechanisms underlying the aged garlic extract- and S-allylcysteine-induced protection

Aged Garlic Extract (AGE) and Its Constituent S-Allyl-Cysteine (SAC) Inhibit the Expression of Pro-Inflammatory Genes Induced in Bronchial Epithelial IB3-1 Cells by Exposure to the SARS-CoV-2 Spike Protein and the BNT162b2 Vaccine

Garlic (Allium sativum L.) is a species of the onion family (Alliaceae ) widely used as a food and a folk medicine. The objective of this study was to determine the effects of AGE (aged garlic extract) on pro-inflammatory genes relevant to COVID-19. To this aim, we treated bronchial epithelial IB3-1 cells with SARS-CoV-2 spike protein (S-protein) or with the COVID-19 BNT162b2 vaccine in the absence or in the presence of AGE. The results obtained demonstrated that AGE is a potent inhibitor of the S-protein-induced expression of the IL-1β, IL-6 and IL-8 genes. Bio-Plex analysis demonstrated that AGE reduced release of IL-6 and IL-8, which were highly induced by S-protein. No inhibition of cells’ growth, toxicity and pro-apoptotic effects were found in AGE-treated cells. The effects of one of the major AGE constituents (S-allyl cysteine, SAC) were studied on the same experimental model systems. SAC was able to inhibit the S-protein-induced expression of IL-1β, IL-6 and IL-8 genes and extracellular release of IL-6 and IL-8, confirming that S-allyl-cysteine is one of the constituents of AGE that is responsible for inhibiting S-protein-induced pro-inflammatory genes. Docking experiments suggest that a possible mechanism of action of SAC is an interference with the activity of Toll-like receptors (TLRs), particularly TLR4, thereby inhibiting NF-κB- and NF-κB-regulated genes, such as IL-1β, IL-6 and IL-8 genes. These results suggest that both AGE and SAC deserve further experimental efforts to verify their effects on pro-inflammatory genes in SARS-CoV-2-infected cells.

Ameliorating effect of S-Allyl cysteine (Black Garlic) on 6-OHDA mediated neurotoxicity in SH-SY5Y cell line

Therapeutic approaches based on isolated compounds derived from natural products are more common in preventing diseases involving inflammation and oxidative stress at present. S-allyl cysteine (SAC) is a promising garlic-derived organosulfur compound with many positive effects in cell models and living systems. SAC has biological activity in various fields, enclosing healing in learning and memory disorders, neurotrophic effects, and antioxidant activity. In this study, we purposed to identify the neuroprotective activity of SAC toward 6-OHDA-induced cell demise in the SH-SY5Ycell line. For this purpose, 6-OHDA-induced cytotoxicity, and biochemical, and gene expression changes were evaluated in SH-SY5Y cells. SH-SY5Y cells grown in cell culture were treated with SAC 24 h before and after 6-OHDA application. Then, cell viability, antioxidant parameters, and gene expressions were measured. Finally, immunofluorescence staining analysis was performed. Our results showed that SAC increased cell viability by 144 % at 80 µg/mL with pre-incubation (2 h). It was observed that antioxidant levels were significantly increased and oxidative stress marker levels were decreased in cells exposed to 6-OHDA after pre-treatment with SAC (p<0.05). SAC supplementation also suppressed the increase in pro-inflammation levels (TNF-α/IL1/IL8) caused by 6-OHDA (p < 0.05). While 8-OHdG and Nop10 expressions were observed at a mild level in SAC pretreatment depending on the dose, 8-OHdG, and Nop10 expressions were observed at a moderate level in SAC treatment after 6-OHDA application (p<0.05). Our findings demonstrate the positive effect of pretreatment with SAC on SH-SY5Y cells injured by 6-OHDA, suggesting that SAC may be beneficial for neuroprotection in regulating oxidative stress and neuronal survival in an in vitro model of Parkinson's disease.

Modulatory L-Alliin Effect on Acute Inflammatory Cytokines in Diet-Induced Obesity Mice

Background/Objectives: The inflammatory response has evolved as a protective mechanism against pathogens and tissue damage. However, chronic inflammation can occur, potentially leading to severe disease. Low-grade chronic inflammation is associated with obesity, and the Th1 cytokine profile plays an important role in this proinflammatory environment. Diet-induced obesity (DIO) can lead to persistent dysbiosis and maintain high concentrations of circulating lipopolysaccharides (LPSs) over prolonged periods of time, resulting in metabolic endotoxemia. In this context, the study of natural immunomodulators has recently increased. Objective: The aim of this study is improve scientific evidence for the immunomodulatory role of L-Alliin in obesity and inflammation. Methods: In the present work, we describe the effect of L-Alliin on serum levels of cytokines in DIO mice after an acute inflammatory challenge. L-Alliin is the main organosulfurized molecule of garlic that has been studied for its numerous beneficial physiological effects in health and disease and is beginning to be considered a nutraceutical. Two situations are simulated in this experimental model, health and chronic, low-grade inflammation that occurs in obesity, both of which are confronted with an acute, inflammation-inducing challenge. Results: Based on our findings, L-Alliin seems to somehow stimulate the cellular chemotaxis by eliciting the release of key molecules, including IL-2, IFN-γ, TNF-α, MCP-1, IL-6, IL-9, and G-CSF. However, the molecular mechanism involved remains unknown. This, in turn, mitigates the risk of severe inflammatory symptoms by preventing the release of IL-1β and its downstream molecules such as IL-1α, GM-CSF, and RANTES. Conclusions: Taken together, these results indicate that L-Alliin can boost immunity in healthy organisms and act as an immunomodulator in low-grade inflammation.

Therapeutic effects of S-allyl-L-cysteine in a mouse endometriosis model and its immunomodulatory effects via regulation of T cell subsets and cytokine expression

BACKGROUND

Endometriosis is a female hormone-dependent gynecological disorder characterized by chronic inflammation. Therefore, the development of novel treatment strategies that can diminish the side effects of the long-term use of hormone-based drugs has been emphasized. S-Allyl-L-cysteine (SAC) is the major constituent of aged garlic extracts. Although the therapeutic effects resulting from the antioxidant properties of SAC have been extensively studied in inflammatory diseases, the therapeutic efficacy of SAC in endometriosis has not been described. In this study, we investigated the therapeutic potential of SAC for endometriosis using a mouse model.

METHODS

An endometriosis mouse model was surgically induced, and oral treatment with 30 mg/kg SAC was administered daily for 28 days. The development of endometriotic lesions was assessed by histological analysis, and the expression profiles of adhesion-, apoptosis-, and inflammation-related genes were evaluated by PCR. Flow cytometric analysis of mouse spleen was conducted to assess changes in lymphocyte subpopulations.

RESULTS

SAC treatment significantly inhibited endometriotic lesion growth. Transcriptional expression analysis revealed the antiadhesion and apoptosis-promoting effects of SAC. In particular, SAC showed an effective immune modulatory response by altering splenic CD4+ and CD8+ T cell subsets and inflammatory cytokine production in the spleen and endometriotic lesions.

CONCLUSION

This study newly elucidates the inhibitory effects of SAC on the growth of endometriosis in a mouse model and describes its immunomodulatory effects.

S-1-Propenylcysteine Enhances Endurance Capacity of Mice by Stimulating Fatty Acid Metabolism via Muscle Isoform of Carnitine Acyltransferase-1

BACKGROUND

Endurance is an important capacity to sustain healthy lifestyles. Aged garlic extract (AGE) has been reported to exert an endurance-enhancing effect in clinical and animal studies, although little is known about its active ingredients and mechanism of action.

OBJECTIVES

This study investigated the potential effect of S-1-propenylcysteine (S1PC), a characteristic sulfur amino acid in AGE, on the swimming endurance of mice, and examined its mechanism of action by a metabolomics-based approach.

METHODS

Male Institute of Cancer Research (ICR) mice (6 wk old) were orally administered either water (control) or S1PC (6.5 mg/kg/d) for 2 wk. The swimming duration to exhaustion was measured at 24 h after the final administration. Nontargeted metabolomic analysis was conducted on the plasma samples obtained from mice after 40-min submaximal swimming bouts. Subsequently, the enzyme activity of carnitine acyltransferase-1 (CPT-1) and the content of malonyl-coenzyme A (CoA), acetyl-CoA, and adenosine triphosphate (ATP) were quantified in heart, skeletal muscles, and liver of mice.

RESULTS

The duration time of swimming was substantially increased in the S1PC-treated mice as compared with the control group. Metabolomic analysis revealed significant alterations in the plasma concentration of the metabolites involved in fatty acid metabolism, in particular medium- or long-chain acylcarnitines in the mice treated with S1PC. Moreover, the administration of S1PC significantly enhanced the CPT-1 activity with the concomitant decrease in the malonyl-CoA content in the heart and skeletal muscles. These effects of S1PC were accompanied by the elevation of the acetyl-CoA and ATP levels to enhance the energy production in those tissues.

CONCLUSIONS

S1PC is a key constituent responsible for the endurance-enhancing effect of AGE. This study suggests that S1PC helps provide energy during endurance exercise by increasing fatty acid metabolism via CPT-1 activation in the heart and skeletal muscles.

Medicinal herbal remedies in neurodegenerative diseases: an update on antioxidant potential

It has been widely documented that medicinal herbal remedies are effective, have fewer side effects than conventional medicine, and have a synergistic effect on health collaborations in the fight against complicated diseases. Traditional treatments for neurological problems in ancient times sometimes involved the use of herbal remedies and conventional methods from East Asian countries including India, Japan, China, and Korea. We collected and reviewed studies on plant-derived neuroprotective drugs and tested them in neurotoxic models. Basic research, preclinical and clinical transgene research can benefit from in silico, in vitro, and in vivo investigations. Research, summaries of the extracts, fractions, and herbal ingredients were compiled from popular scientific databases, which were then examined according to origin and bioactivity. Given the complex and varied causes of neurodegeneration, it may be beneficial to focus on multiple mechanisms of action and a neuroprotection approach. This approach aims to prevent cell death and restore function to damaged neurons, offering promising strategies for preventing and treating neurodegenerative diseases. Neurodegenerative illnesses can potentially be treated with natural compounds that have been identified as neuroprotective agents. To gain deeper insights into the neuropharmacological mechanisms underlying the neuroprotective and therapeutic properties of naturally occurring antioxidant phytochemical compounds in diverse neurodegenerative diseases, this study aims to comprehensively review such compounds, focusing on their modulation of apoptotic markers such as caspase, Bax, Bcl-2, and proinflammatory markers. In addition, we delve into a range of efficacies of antioxidant phytochemical compounds as neuroprotective agents in animal models. They reduce the oxidative stress of the brain and have been shown to have anti-apoptotic effects. Many researches have demonstrated that plant extracts or bioactive compounds can fight neurodegenerative disorders. Herbal medications may offer neurodegenerative disease patients' new treatments. This may be a cheaper and more culturally appropriate alternative to standard drugs for millions of people with age-related NDDs.

Aged garlic therapeutic intervention targeting inflammatory pathways in pathogenesis of bowel disorders

Inflammatory bowel diseases (IBD), which include Crohn's disease and ulcerative colitis, manifest as a result of intricate interactions involving genetic predisposition, environmental factors, intestinal microbiota dynamics, and immune dysregulation, ultimately leading to persistent mucosal inflammation. Addressing this complex pathology requires a nuanced understanding to inform targeted therapeutic strategies. Consequently, our study explored the viability of Aged Garlic Extract (AGE) as an alternative therapeutic regimen for IBD management. Utilizing gas chromatography-mass spectrometry (GC-MS) and scanning electron microscopy (SEM), we characterized AGE, revealing distinctions from Fresh Garlic Extract (FGE), particularly the absence of allicin in AGE and accompanying structural alterations. In In-Vivo experiments employing an IBD rat model, AGE intervention exhibited remarkable antioxidant, antibacterial, and anti-inflammatory properties. Noteworthy outcomes included improved survival rates, mitigation of intestinal damage, restoration of gut microbial diversity, reinforcement of tight junctions, and reversal of mitochondrial dysfunction. Collectively, these effects contributed to the preservation of enterocyte integrity and the attenuation of inflammation. In conclusion, the unique chemical composition of AGE, coupled with its substantial influence on gut microbiota, antioxidant defenses, and inflammatory pathways, positions it as a promising adjunctive therapy for the management of IBD. These observations, synergistically considered with existing research, provide significant insights into the potential utility of AGE in addressing the intricate pathophysiology inherent to IBD. The potential strength of study and rationale of using AGE against IBD includes exploring alternative therapeutic regimens if conventional treatments are associated with side effects, identification of potential hotspots/pathways involved in disease progression and study can provide economically cheaper and naturally occurring alternative to patient community who are struggling to afford expensive medications. These promising findings underscore the necessity for additional investigations to ascertain the feasibility of clinical translation, thereby substantiating the potential therapeutic role of AGE in the management of IBD.

S-allyl-cysteine triggers cytotoxic events in rat glioblastoma RG2 and C6 cells and improves the effect of temozolomide through the regulation of oxidative responses

Glioblastoma (GBM) is an aggressive form of cancer affecting the Central Nervous System (CNS) of thousands of people every year. Redox alterations have been shown to play a key role in the development and progression of these tumors as Reactive Oxygen Species (ROS) formation is involved in the modulation of several signaling pathways, transcription factors, and cytokine formation. The second-generation oral alkylating agent temozolomide (TMZ) is the first-line chemotherapeutic drug used to treat of GBM, though patients often develop primary and secondary resistance, reducing its efficacy. Antioxidants represent promising and potential coadjutant agents as they can reduce excessive ROS formation derived from chemo- and radiotherapy, while decreasing pharmacological resistance. S-allyl-cysteine (SAC) has been shown to inhibit the proliferation of several types of cancer cells, though its precise antiproliferative mechanisms remain poorly investigated. To date, SAC effects have been poorly explored in GBM cells. Here, we investigated the effects of SAC in vitro, either alone or in combination with TMZ, on several toxic and modulatory endpoints-including oxidative stress markers and transcriptional regulation-in two glioblastoma cell lines from rats, RG2 and C6, to elucidate some of the biochemical and cellular mechanisms underlying its antiproliferative properties. SAC (1-750 µM) decreased cell viability in both cell lines in a concentration-dependent manner, although C6 cells were more resistant to SAC at several of the tested concentrations. TMZ also produced a concentration-dependent effect, decreasing cell viability of both cell lines. In combination, SAC (1 µM or 100 µM) and TMZ (500 µM) enhanced the effects of each other. SAC also augmented the lipoperoxidative effect of TMZ and reduced cell antioxidant resistance in both cell lines by decreasing the TMZ-induced increase in the GSH/GSSG ratio. In RG2 and C6 cells, SAC per se had no effect on Nrf2/ARE binding activity, while in RG2 cells TMZ and the combination of SAC + TMZ decreased this activity. Our results demonstrate that SAC, alone or in combination with TMZ, exerts antitumor effects mediated by regulatory mechanisms of redox activity responses. SAC is also a safe drug for testing in other models as it produces non-toxic effects in primary astrocytes. Combined, these effects suggest that SAC affords antioxidant properties and potential antitumor efficacy against GBM.

Genetic Targets and Applications of Iron Chelators for Neurodegeneration with Brain Iron Accumulation

Neurodegeneration with brain iron accumulation (NBIA) is a group of neurodegenerative diseases that are typically caused by a monogenetic mutation, leading to development of disordered movement symptoms such as dystonia, hyperreflexia, etc. Brain iron accumulation can be diagnosed through MRI imaging and is hypothesized to be the cause of oxidative stress, leading to the degeneration of brain tissue. There are four main types of NBIA: pantothenate kinase-associated neurodegeneration (PKAN), PLA2G6-associated neurodegeneration (PLAN), mitochondrial membrane protein-associated neurodegeneration (MKAN), and beta-propeller protein-associated neurodegeneration (BPAN). There are no causative therapies for these diseases, but iron chelators have been shown to have potential toward treating NBIA. Three chelators are investigated in this Review: deferoxamine (DFO), desferasirox (DFS), and deferiprone (DFP). DFO has been investigated to treat neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD); however, dose-related toxicity in these studies, as well as in PKAN studies, have shown that the drug still requires more development before it can be applied toward NBIA cases. Iron chelation therapies other than the ones currently in clinical use have not yet reached clinical studies, but they may possess characteristics that would allow them to access the brain in ways that current chelators cannot. Intranasal formulations are an attractive dosage form to study for chelation therapy, as this method of delivery can bypass the blood-brain barrier and access the CNS. Gene therapy differs from iron chelation therapy as it is a causal treatment of the disease, whereas iron chelators only target the disease progression of NBIA. Because the pathophysiology of NBIA diseases is still unclear, future courses of action should be focused on causative treatment; however, iron chelation therapy is the current best course of action.

In-vitro antioxidant and anti-inflammatory potential along with p.o. pharmacokinetic profile of key bioactive phytocompounds of Snow Mountain Garlic: a comparative analysis vis-à-vis normal garlic

Snow mountain garlic (SMG) is a trans-Himalayan medicinal plant used in the traditional medicine system for several ailments, including inflammatory arthritis. Research studies are insufficient to validate its folk medicinal applications. In the present study, the comparative abundance of its key bioactive phytocompounds, viz., S-allyl-L-cysteine (SAC), alliin, and S-methyl-L-cysteine (SMC) against normal garlic were assessed using the LC-MS/MS-MRM method. In addition, the study also explored the antioxidant and anti-inflammatory potency of crude extract of SMG and purified signature phytocompounds (i.e., SMC, SAC, and alliin) in comparison with normal garlic and dexamethasone in LPS-stimulated RAW264.7 macrophage cells. The LC-MS/MS-MRM study revealed significant differences among SMG and normal garlic, viz., alliin 22.8-fold higher in SMG, and SMC could be detected only in SMG. In the bioassays, SMG extract and purified signature phytocompounds significantly downregulated oxidative damage in activated macrophages, boosting endogenous antioxidants' activity. SMG extract-treated macrophages significantly suppressed NF-κB expression and related inflammatory indicators such as cytokines, COX-2, iNOS, and NO. Notably, the observed anti-inflammatory and antioxidant bioactivities of SMG extract were comparable to signature phytocompounds and dexamethasone. In addition, SAC being uniformly found in SMG and normal garlic, its comparative pharmacokinetics was studied to validate the pharmacodynamic superiority of SMG over normal garlic. Significantly higher plasma concentrations (Cmax), half-life (t1/2), and area under curve (AUC) of SAC following SMG extract administration than normal garlic validated the proposed hypothesis. Thus, the abundance of bioactive phytocompounds and their better pharmacokinetics in SMG extract might be underlying its medicinal merits over normal garlic.

Network pharmacology-based approach to elucidate the pharmacologic mechanisms of natural compounds from Dictyostelium discoideum for Alzheimer's disease treatment

Alzheimer's disease (AD) is increasingly becoming a major public health concern in our society. While many studies have explored the use of natural polyketides, alkaloids, and other chemical components in AD treatment, there is an urgent need to clarify the concept of multi-target treatment for AD. This study focuses on using network pharmacology approach to elucidate how secondary metabolites from Dictyostelium discoideum affect AD through multi-target or indirect mechanisms. The secondary metabolites produced by D. discoideum during their development were obtained from literature sources and PubChem. Disease targets were selected using GeneCards, DisGeNET, and CTD databases, while compound-based targets were identified through Swiss target prediction and Venn diagrams were used to find intersections between these targets. A network depicting the interplay among disease, drugs, active ingredients, and key target proteins (PPI network) was formed utilizing the STRING (Protein-Protein Interaction Networks Functional Enrichment Analysis) database. To anticipate the function and mechanism of the screened compounds, GO and KEGG enrichment analyses were conducted and visually presented using graphs and bubble charts. After the screening phase, the top interacting targets in the PPI network and the compound with the most active target were chosen for subsequent molecular docking and molecular dynamic simulation studies. This study identified nearly 50 potential targeting genes for each of the screened compounds and revealed multiple signaling pathways. Among these pathways, the inflammatory pathway stood out. COX-2, a receptor associated with neuroinflammation, showed differential expression in various stages of AD, particularly in pyramidal neurons during the early stages of the disease. This increase in COX-2 expression is likely induce by higher levels of IL-1, which is associated with neuritic plaques and microglial cells in AD. Molecular docking investigations demonstrated a strong binding interaction between the terpene compound PQA-11 and the neuroinflammatory receptor COX2, with a substantial binding affinity of -8.4 kcal/mol. Subsequently, a thorough analysis of the docked complex (COX2-PQA11) through Molecular Dynamics Simulation showed lower RMSD, minimal RMSF fluctuations, and a reduced total energy of -291.35 kJ/mol compared to the standard drug. These findings suggest that the therapeutic effect of PQA-11 operates through the inflammatory pathway, laying the groundwork for further in-depth research into the role of secondary metabolites in AD treatment.

The use of active compounds to shape the quality of active double-layer films based on furcellaran intended for packaging salad-dressing - Assessment of utilitarian and storage properties

In order to obtain innovative, high-quality biodegradable packaging, double-layer films based on furcellaran and gelatin, enriched with plant extracts were created. The films were assessed considering their potential utility, applications and environmental impact. The mechanical properties over a period of nine months were studied and it was noted that the passing of time had a beneficial effect on these parameters. The antioxidant properties was also examined, with the highest results obtained using the DPPH and metal chelating activity methods for GE (76.64 % and 9.85 % respectively), while this film showed the lowest FRAP value (5.99 %) compared to the highest obtained for DTE (52.62 %). For the first time, the possibility of using the double-layer active FUR/GEL film as packaging for salad-dressing was evaluated, but no improvement in parameters was observed regardless of the extract used. The environmental impact analysis showed the ability to completely decomposed in vermicompost within several days.

Psychochemical changes and functional properties of organosulfur and polysaccharide compounds of black garlic (Allium sativum L.)

Background

Black garlic is one of the functional food products made from garlic which is processed through aging to improve sensory value and nutritional quality. Aging conditions has a major impact on the psychochemical and functional properties changes of black garlic which is closely related to organosulfur compounds and polysaccharides as the largest component in garlic.

Scope and approach

The method used in this research is a systematic review with the aim of research to determine the relationship between reactions during aging and changes in organosulfur, polysaccharides and non-enzymatic browning product compounds as well as the function of black garlic by focusing on certain aspects of aging including temperature, humidity, time, microorganism activity, and pre-treatment application.

Key findings and conclusions

Maillard reaction and polysaccharide degradation are still be the dominant reactions and play an important role in black garlic production. High hydrostatic pressure pretreatment could maintains the quality of black garlic so that the black garlic has the same taste characteristics as black garlic in general. Antioxidant properties in black garlic shown increase during thermal treatment. In addition, it is known that the activity of microorganisms plays a role and being potential to increase the quality value of black garlic as well as the antimicrobial activity.

Phenylephrine Enhances the Mitogenic Effect of S-Allyl-L-cysteine on Primary Cultured Hepatocytes through Protein Kinase C-Induced B-Raf Phosphorylation

The co-mitogenic effects of the α1-adrenoceptor agonist phenylephrine on S-allyl-L-cysteine (SAC)-induced hepatocyte proliferation were examined in primary cultures of adult rat hepatocytes. The combination of phenylephrine (10-10-10-6 M) and SAC (10-6 M) exhibited a significant dose-dependent increase in the number of hepatocyte nuclei and viable cells compared to SAC alone. This combination also increased the progression of hepatocyte nuclei into the S-phase. The potentiating effect of phenylephrine on SAC-induced cell proliferation was counteracted by prazosin (an α1-adrenergic receptor antagonist) and GF109203X (selective protein kinase C (PKC) inhibitor). In addition, PMA (direct PKC activator) potentiated the proliferative effects of SAC similarly to phenylephrine. In essence, these findings suggest that PKC activity plays a crucial role in enhancing SAC-induced cell proliferation. Moreover, the effects of phenylephrine on SAC-induced Ras activity, Raf phosphorylation, and extracellular signal-regulated kinase 2 (ERK2) phosphorylation were investigated. Phenylephrine (or PMA) in combination with SAC did not augment Ras activity, but further increased ERK2 phosphorylation and its upstream B-Raf phosphorylation. These results indicate that PKC activation, triggered by stimulating adrenergic α1 receptors, further amplifies SAC-induced cell proliferation through enhanced ERK2 phosphorylation via increased B-Raf-specific phosphorylation in primary cultured hepatocytes.

Effect of the Combination of Different Therapies on Oxidative Stress in the Experimental Model of Multiple Sclerosis

Oxidative stress is heavily involved in several pathological features of Multiple Sclerosis (MS), such as myelin destruction, axonal degeneration, and inflammation. Different therapies have been shown to reduce the oxidative stress that occurs in the animal model of MS, experimental autoimmune encephalomyelitis (EAE). Some of these therapies are transcranial magnetic stimulation (TMS), extra virgin olive oil (EVOO) and S-allyl cysteine (SAC). This study aims to test the antioxidant effect of these three therapies, to compare the efficacy of SAC versus TMS and EVOO, and to analyze the effect of combining SAC + TMS and SAC and EVOO. Seventy Dark Agouti rats were used, which were divided into Control group; Vehicle group; Mock group; SAC; EVOO; TMS; SAC + EVOO; SAC + TMS; EAE; EAE + SAC; EAE + EVOO; EAE + TMS; EAE + SAC + EVOO; EAE + SAC + TMS. The TMS consisted of an oscillatory magnetic field in the form of a sine wave with a frequency of 60 Hz and an amplitude of 0.7mT (EL-EMF) applied for two hours in the morning, once a day, five days a week. SAC was administered at a dose of 50 mg/kg body weight, orally daily, five days a week. EVOO represented 10% of their calorie intake in the total standard daily diet of rats AIN-93G. All treatments were maintained for 51 days. TMS, EVOO and SAC, alone or in combination, reduce oxidative stress, increasing antioxidant defenses and also lowering the clinical score. Combination therapies do not appear to be more potent than individual therapies against the oxidative stress of EAE or its clinical symptoms.

L-arginine and aged garlic extract for the prevention of migraine: a study protocol for a randomised, double-blind, placebo-controlled, phase-II trial (LARGE trial)

Background

Migraine is a common and distressing neurological condition characterised by recurrent throbbing headaches, nausea and heightened sensitivity to light and sound. Accumulating evidence suggests that cerebral arteries dilate during migraine, causing distal microvessels to constrict, which could activate nociceptors and cause onset of headache pain. If so, preventing or attenuating chronic microvascular constriction, and promoting a dilatory phenotype, may reduce frequency and/or severity of migraines. The primary aim of the L-Arginine and Aged Garlic Extract (LARGE) trial is to investigate whether oral treatment with dietary nutraceuticals, L-arginine and aged garlic extract (AGE), both systemic vasodilatory agents, will alleviate migraine frequency, duration and severity in adults with chronic frequent episodic migraines.

Methods

The study is a randomised double-blind placebo-controlled phase-II single-site clinical trial conducted in Perth, Australia. The target sample is to recruit 240 participants diagnosed with chronic frequent episodic migraines between 18 and 80 years of age. Participants will be randomised to one of four treatment groups for 14 weeks (placebo induction for 2 weeks, followed by 12 weeks on one of the respective treatment arms): placebo, L-arginine, AGE, or a combination of L-arginine and AGE. The doses of L-arginine and AGE are 1.5 g and 1 g daily, respectively. The primary outcome is to assess migraine response using change in migraine frequency and intensity between baseline and 12 weeks. Secondary outcomes include the impact of L-arginine and/or AGE on photosensitivity, retinal vessel changes, and blood biomarker concentrations of vascular tone, following a 12-week intervention.

Discussion

The protocol describes the oral administration of 2 nutraceutical-based interventions as possible prophylactic treatments for chronic frequent episodic migraines, with potential for direct clinical translation of outcomes. Potential limitations of the study include the fixed-dose design of each treatment arm and that in vivo neuroimaging methods, such as magnetic resonance imaging (MRI), will not be conducted to determine putative cerebro-vasodilatory changes to coincide with the outcome measures. Dose-response studies may be indicated.

Trial registration

The trial was retrospectively registered with the Australian New Zealand Clinical Trials Registry ACTRN12621001476820 (Universal Trial Number: U1111-1268-1117) on 04/08/2021. This is protocol version 1, submitted on 25/11/2022.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-023-03149-y.

The Pharmacological Activity of Garlic (Allium sativum) in Parkinson's Disease: From Molecular Mechanisms to the Therapeutic Potential

Parkinson's disease (PD), one of the most common neurological diseases worldwide, is mainly characterized neuropathologically by the dopaminergic neurodegeneration in the substantia nigra pars compacta of the brainstem. Genetic and environmental factors contribute to PD pathophysiology through modulation of pleiotropic cellular mechanisms. The currently available treatment options focus only on replenishing dopamine and do not alter disease progression. Interestingly, garlic (Allium sativum), globally famed for its flavor and taste-enhancing properties, has shown protective activity in different PD models. Numerous chemical constituents of garlic, mainly the organosulfur compounds, have been shown to exhibit anti-Parkinsonian effects by targeting oxidative stress, mitochondrial impairment, and neuroinflammation-related signaling. However, despite its therapeutic potential against PD, the major bioactive components of garlic display some stability issues and some adverse effects. In the present review, we explore the therapeutic potential of garlic and its major constituents in PD, the molecular mechanisms responsible for its pharmaceutical activity, and the associated limitations that need to be overcome for its future potential use in clinical practice.

A review on the effect of garlic on diabetes, BDNF, and VEGF as a potential treatment for diabetic retinopathy

BACKGROUND

Garlic is one of the favorite herbs in traditional medicine that has been reported to have many medicinal features. The aim of the current study is to review the latest documents on the effect of garlic on diabetes, VEGF, and BDNF and, finally, to review the existing studies on the effect of garlic on diabetic retinopathy.

MAIN TEXT

The therapeutic effect of garlic on diabetes has been investigated in various studies. Diabetes, especially in advanced stages, is associated with complications such as diabetic retinopathy, which is caused by the alteration in the expression of molecular factors involved in angiogenesis, neurodegeneration, and inflammation in the retina. There are different in-vitro and in-vivo reports on the effect of garlic on each of these processes. Considering the present concept, we extracted the most related English articles from Web of Science, PubMed, and Scopus English databases from 1980 to 2022. All in-vitro and animal studies, clinical trials, research studies, and review articles in this area were assessed and classified.

RESULT AND CONCLUSION

According to previous studies, garlic has been confirmed to have beneficial antidiabetic, antiangiogenesis, and neuroprotective effects. Along with the available clinical evidence, it seems that garlic can be suggested as a complementary treatment option alongside common treatments for patients with diabetic retinopathy. However, more detailed clinical studies are needed in this field.

In silico and in vitro investigation of anticancer effect of newly synthesized nonivamide-s-allyl cysteine ester

Nonivamide (NOV), less pungent analogue of capsaicin present in various Capsicum species is known for various biological properties. S-allyl cysteine (SAC) abundantly present in aged garlic extract is gaining importance for anticancer property. NOV was esterified with SAC to increase the biological activity. In silico ADME analysis revealed the drug-likeness of NOV-SAC. Molecular docking and dynamics simulation analysis were done to understand the interaction of NOV-SAC with therapeutic target proteins (human estrogen receptor α, tumo protein negative regulator mouse double minute 2, B-cell lymphoma 2 and cyclin-dependent kinase 2) to treat cancer. NOV-SAC interacted with these proteins stably with favorable binding energy which was calculated through MMGBSA method. In line with in silico results, NOV-SAC showed antiproliferative activity against breast cancer cell line (MCF-7). NOV-SAC treatment increased ROS generation, decreased the antioxidant level, arrested cells at G1/S phase, disrupted mitochondrial membrane potential and initiated DNA fragmentation. The expression of p53 is increased by NOV-SAC treatment, in concordance the ratio of Bcl-2/Bax was decreased. Altogether, NOV-SAC was synthesized for the first time and it induced apoptosis in MCF-7 cells through triggering ROS generation and increasing the expression of p53. The in silico results has been mirrored in in vitro analysis of NOV-SAC against cancer cell line.Communicated by Ramaswamy H. Sarma.

Ameliorative effect of biosynthesized titanium dioxide nanoparticles using garlic extract on the body weight and developmental toxicity of liver in albino rats compared with chemically synthesized nanoparticles

The application of metallic nanoparticles poses risks to human and animal health. Titanium dioxide nanoparticles (TiO₂NPs) are the most commonly synthesized metallic oxides in the world. Exposure to TiO₂NPs can cause toxicity in the target organisms. This study aimed to evaluate the effects of green and chemical TiO₂NPs on maternal and embryo-fetal livers. Green TiO₂NPs using garlic extract (GTiO₂NPs) and chemical TiO₂NPs (CHTiO₂NPs) were synthesized and characterized by x-ray powder diffraction and high-resolution transmission electron microscopy. The cytotoxicity of both chemical and green TiO₂NPs was determined against HepG₂ cell lines. Fifty pregnant female Albino rats were equally and randomly divided into five groups. Group 1 was kept as a control. Groups 2 and 3 were orally treated with 100 and 300 mg/kg body weight of CHTiO₂NPs, respectively. Groups 4 and 5 were orally treated with 100 and 300 mg/kg of GTiO₂NPs, respectively, from day 6 to 19 of gestation. All dams were euthanized on gestation day 20. All live fetuses were weighed and euthanized. Blood and tissue samples were collected for biochemical, histopathological, and Bax-immunohistochemical expression analyses. Our results indicated that garlic could be used as a reducing agent for the synthesis of TiO₂NPs, and the produced NPs have no toxic effect against HepG₂ cells compared with CHTiO₂NPs. The maternal and fetal bodyweights were greatly reduced among the chemically TiO₂NPs induced animals. The mean serum level of AST and ALT activities and the total protein level significantly increased when TiO₂NPs were administered at high doses. Histologically, the CHTiO₂NPs-treated groups revealed vacuolated and necrotized hepatocytes with congested and dilated blood vessels in the fetal and maternal livers. The immunohistochemistry revealed distinct positive staining of Bax expressed in the hepatocytes. Nevertheless, the biosynthesis of TiO₂NPs using garlic extract had a minimal effect on the normal architecture of the liver. It could be concluded that the bioactivity of TiO₂NPs can be modified by green synthesis using garlic extract. Compared to the CHTiO₂NPs, the exposure to GTiO₂NPs showed reduced liver damage in maternal and embryo-fetal rats.

Protective effects of volatile components of aged garlic extract against ultraviolet B-induced apoptosis in human skin fibroblasts

Aged garlic extract (AGE) has been shown to protect the skin against UV-induced damage, but effects of its volatile components remain unknown. We investigated the effects of the volatile fraction of AGE on the responses of cultured skin fibroblasts subjected to UV-B irradiation. UV-B irradiation (20 mJ/cm² ) reduced the cell viability to 55% of control. The nonvolatile and volatile fractions of AGE inhibited the UV-B-induced reduction of cell viability; the cell viabilities were 100% and 73%, respectively. The volatile fraction inhibited the UV-B-induced increase in apoptotic cell death by 28%. The volatile fraction also inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs) induced by UV-B irradiation. GC-MS analysis revealed that a large number of volatile compounds were generated during aging of garlic. These results suggest that the volatile fraction of AGE has protective effects against the UV-B-induced death of skin fibroblasts, and that this effect may partly be due to an inhibition of apoptosis via the downregulation of MAPK signaling. The volatile compounds of AGE may have beneficial applications for skin health. PRACTICAL APPLICATIONS: In this study, we investigated the effects of AGE against cell damage of UV-B-irradiated human skin fibroblasts. The aging process of garlic produced characteristic volatile compounds that have significant protective effects against UV-induced cell damage. Our results demonstrated that the aging process is a suitable method to develop added value in garlic extracts to improve skin health.

Black solo garlic protects hepatic and renal cell function in streptozotocin-induced rats

Black solo garlic (BSG) has been evaluated for its ability to reduce free radicals; however, the safety test on kidney and liver function has not been evaluated. This study aimed to examine the effect of brewed BSG on the liver (total protein, albumin, glutathione S-transferase/GST) and kidney (urea, creatinine, and β 2 -microglobulin) function in streptozotocin (STZ)-induced white rats. The experimental animals were randomly divided into six groups, each including five animals. The groups consist of the normal control group, the STZ-induced control group, the BSG treatment group with doses 6.5, 13.5, and 26 g/kg body weight, and metformin positive control. After STZ induction, the serum levels of GST, total protein, and albumin are decreased. After treatment with BSG, the serum level of GST, total protein, and albumin increased significantly (p < 0.05). The levels of urea, creatinine, and β2-microglobulin increased after STZ induction. After treatment of BSG, levels of urea, creatinine, and β2-microglobulin are decreased significantly (p < 0.05). These results suggest that BSG use is safe for the liver and kidneys of STZ-induced rats.

The efficacy of applying some plants and herbs in cancer therapy for humans and animals – a comperhensive review

Cancer is a challenging ailment and represents the main reason for death worldwide for humans and animals. Although great developments have hindered cancer progression, several adverse effects are associated with modern chemotherapy. Natural remedies, such as the usage of medicinal plant or their products in cancer treatment, may decrease prejudicial side properties. Recently, the modern research scheme and innovative screening practices for herbs or plants have enabled phytochemical discovery for the prevention and treatment of cancer. This criticism highlights herbs such as acacia, basil, black seeds, cedar, castus, ficus, garlic, ginger, indigo, onion, pomegranate, quince, and thyme, promising anticancer effects. The present review also revealed the mode of action of each herb as anticancer effects at level in vitro and in vivo studies. The item also totalizes the vital mechanisms and signaling molecules involved in preventing cancer diseases. This will fill the investigate gap in the exploration of using natural molecules and encourage researchers in clinical trials of anticancer agents from herbs for humans and animals.

Natural treatments for erectile dysfunction: A focus on mobile health applications

To the Editor, Erectile dysfunction (ED) is defined as the persistent inability to achieve or maintain penile erection sufficient for satisfactory sexual performance. ED represents one of the most important male sexual dysfunctions with a prevalence of 52% and affecting more than 150 million men worldwide (estimated to be 322 million worldwide for 2025) [...]

Neuronutraceuticals Combating Neuroinflammaging: Molecular Insights and Translational Challenges—A Systematic Review

Neuropathologies, such as neuroinflammaging, have arisen as a serious concern for preserving the quality of life due to the global increase in neurodegenerative illnesses. Nowadays, neuronutraceuticals have gained remarkable attention. It is necessary to investigate the bioavailability, off-target effects, and mechanism of action of neuronutraceuticals. To comprehend the comprehensive impact on brain health, well-designed randomized controlled trials testing combinations of neuronutraceuticals are also necessary. Although there is a translational gap between basic and clinical research, the present knowledge of the molecular perspectives of neuroinflammaging and neuronutraceuticals may be able to slow down brain aging and to enhance cognitive performance. The present review also highlights the key emergent issues, such as regulatory and scientific concerns of neuronutraceuticals, including bioavailability, formulation, blood–brain permeability, safety, and efficacy.

The Effects of Processing Time on the Total Phenolic, Flavonoid Content, and Antioxidant Activity of Multi Bulb and Single Bulb Black Garlic

Black garlic is produced by processing multi-bulb garlic (Allium sativum) or single-bulb garlic in high temperature and high humidity for several days. Black garlic has many health benefits, such as an antioxidant activity resulting from its compound, including groups of flavonoid and phenolic compounds. This study aimed to analyze the effect of aging time on multi-bulb and single-bulb black garlic on the content of total phenolic, flavonoid, and antioxidant activity. Black garlic was processed at a 60-70°C heating temperature and 70-80% relative humidity for 25 days. Determination of total phenol and flavonoid contents was conducted using spectrophotometric methods with gallic acid as a standard of total phenolic and quercetin as a standard of flavonoid, while the antioxidant activity was determined by DPPH radical reduction. The results showed that total phenolic contents (% w/w GAE), flavonoids contents (% w/w QE), and EC50 values at 0 until day 25 increased on a particular day in multi-bulb and single-bulb black garlic. The optimal total phenolic content of both black garlic was obtained by heating for 20 days, flavonoid content of multi-bulb garlic for 10 days, and single-bulb black garlic for 15 days. Highest antioxidant activity was obtained on days 20 and 25 for single-bulb black garlic and multi-bulb black garlic, respectively. The aging time of black garlic affects total phenolic, flavonoid content, and antioxidant activity. In general, longer processing time caused an increase in the total phenolic content, flavonoid content, and antioxidant activity of both black garlics. Multi-bulb black garlic showed higher phenolic or flavonoid content and antioxidant activity than single-bulb black garlic.

S-allylcysteine potently protects against PhIP-induced DNA damage via Nrf2/AhR signaling pathway modulation in normal human colonic mucosal epithelial cells

SCOPE

This study aimed to investigate whether S-allylcysteine (SAC) exerts chemoprophylactic effects on foodborne carcinogenicity caused by 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in normal human colonic mucosal epithelial cells.

METHODS AND RESULTS

Cellular thermal shift assays showed that SAC had an affinity for the Keap1 protein. Moreover, SAC may also dampen the binding of Keap1 and NF-E2-related factor 2 (Nrf2) by inhibiting p-p38 and increasing the phosphorylation of ERK1/2 and AKT, thereby inducing Nrf2/HO-1 signaling and upregulating the ratio of GSH to GSH/GSSG, which inhibits PhIP-induced oxidative stress and DNA damage. In addition, SAC significantly downregulates the aryl hydrocarbon receptor signaling pathway, suggesting that SAC may potentially impede the metabolic transformation of carcinogens.

CONCLUSION

Collectively, these findings suggest that SAC protects against PhIP-induced reactive oxygen species production and DNA damage by modulating the Nrf2/AhR signaling pathway, which may have significant potential as a novel chemopreventive agent. This article is protected by copyright. All rights reserved.

Identification of tryptophanase from Escherichia coli for the synthesis of S-allyl-l-cysteine and related S-substituted cysteine derivatives

A wide variety of S-substituted cysteine derivatives occur in plant metabolites. For example, S-allyl-l-cysteine (SAC), mainly contained in garlic, gathers huge interest because of its favorable bioactivities for human health. However, conventional methods for preparing SAC suffer from several drawbacks with regard to efficiency and toxicity, which highlights the need for improved processes for SAC synthesis. This study aims to develop a novel bioprocess to produce SAC by microbial enzymes from easily available substrates. We found that Escherichia coli had the ability to synthesize SAC from allyl mercaptan, pyruvic acid, and ammonium sulfate. An enzyme purification through 3-step column chromatography, followed by determination of the N-terminal amino acid sequence revealed that tryptophanase (TnaA) was the enzyme responsible for SAC formation. Although the enzyme catalyzed the reversible reaction for synthesizing and degrading SAC, the degradation proceeded significantly faster than the synthesis. Interestingly, TnaA catalyzed the synthesis of a wide range of S-substituted cysteines with alkyl chains or aromatic rings, some of which are present in Allium and Petiveria plants. Our results showed a novel substrate specificity of TnaA toward various S-substituted cysteine. TnaA is a promising biocatalyst for developing a new process to supply various valuable S-substituted cysteine derivatives for medicinal and health-promoting applications.

Cell proliferation effects of S-allyl-L-cysteine are associated with phosphorylation of janus kinase 2, insulin-like growth factor type-I receptor tyrosine kinase, and extracellular signal-regulated kinase 2 in primary cultures of adult rat hepatocytes

The cell proliferation effect of S-allyl-L-cysteine (SAC) and its mechanisms were examined in primary cultures of adult rat hepatocytes. In serum-free cultivation, SAC (10^-6 M)-stimulated hepatocytes showed significant proliferation compared to control at 5-h culture; the effect was dependent on the culture time and the dose of SAC (EC₅₀ value 8.58 × 10^-8 M). In addition, SAC-stimulated hepatocytes significantly increased mRNA expression levels of c-Myc and c-Fos at 1 h and cyclin B1 at 3.5 and 4 h, respectively. In contrast, alliin and allicin, structural analogs of SAC, did not show these effects observed with SAC. The SAC-induced hepatocyte proliferation effects were completely suppressed by monoclonal antibodies against growth hormone receptor and insulin-like growth factor type-I (IGF-I) receptor, respectively. Furthermore, the Janus kinase 2 (JAK2) inhibitor TG101209, phospholipase C (PLC) inhibitor U-73122, IGF-I receptor tyrosine kinase (RTK) inhibitor AG538, PI3 kinase inhibitor LY294002, MEK inhibitor PD98059, and mTOR inhibitor rapamycin completely suppressed the SAC-induced hepatocyte proliferation. JAK2 (p125 kDa) phosphorylation in cultured hepatocytes peaked 5 min after SAC stimulation. SAC-induced IGF-I RTK (p95 kDa) and ERK2 (p42 kDa) phosphorylation had slower rises than JAK2, peaking at 20 and 30 min, respectively. These results indicate that SAC promoted cell proliferation by growth hormone receptor/JAK2/PLC pathway activation followed by activation of the IGF-I RTK/PI3K/ERK2/mTOR pathway in primary cultures of adult rat hepatocytes.

Modulatory role of garlic ( Allium sativum) extract against cisplatin- induced nephrotoxicity in female albino rats and their offspring

Background: Cisplatin (CP) is one of the chemotherapeutic drugs widely utilized in the treatment of several malignancies. However, recently; its use has been limited because of its hazardous health drawbacks. Previous researches confirmed that CP has severe deleterious side effects on pregnant mothers and their fetuses. Garlic ( Allium sativum) extract has been claimed to exhibit potent antioxidative and free radical scavenging abilities. Aim: This work is mainly designed to evaluate the potential therapeutic role of garlic extract against CP-induced nephrotoxicity in pregnant rats and their offspring. Methods: 24 pregnant rats were used in the current study. They were randomly allocated into four groups (n=6):  control, garlic, CP, and CP + garlic group. At the end of the weaning period, the mothers and the offsprings of all groups were sacrificed, the kidneys were immediately excised, and processed for histological and biochemical investigations. Also, blood samples were withdrawn and processed for estimation of the assigned biochemical parameters.   Results: The renal histological sections from CP-treated mother rats displayed pronounced histopathological lesions however, their offspring showed mild renal histopathological lesions if compared with those of their mothers. The levels of renal tissue Superoxide dismutase, catalase, and glutathione peroxidase enzymes were significantly decreased. On the contrary, the levels of malondialdehyde, serum urea, and creatinine were significantly increased in CP-treated mother rats and their offspring as compared with control. The percentage value of caspase 3 activity was markedly elevated in the renal tissues of CP-treated mother rats and their offspring compared to the control group. Supplementation of garlic extract to the CP treated rats; the overall histological lesions, as well as biochemical parameters, were restored nearly to the control ones. It is concluded that garlic ( Allium sativum) extract has a powerful ameliorative role against CP-induced nephrotoxicity in pregnant rats and their offspring.

Improved microvascular reactivity after aged garlic extract intake is not mediated by hydrogen sulfide in older adults at risk for cardiovascular disease: a randomized clinical trial

PURPOSE

This study aimed to investigate the effects of AGE on microvascular reactivity, systolic blood pressure (SBP), and diastolic blood pressure (DBP) in older individuals at high risk for cardiovascular disease (CVD). Urinary thiosulfate was also investigated as an indirect marker of endogenous hydrogen sulfide (H₂S) synthesis. The study was conducted in a randomized, double-blind, crossover, and placebo-controlled way.

METHODS

Twenty-eight participants (14 male), 67 ± 6 years old with CVD risk factors, ingested 2.4 g of AGE or placebo (PLA). Near-infrared spectroscopy evaluated tissue oxygen saturation (StO₂) during a vascular occlusion test (30 s baseline, 5 min occlusion, and 2 min reperfusion). The upslope of StO₂ signal after cuff release was calculated to measure microvascular reactivity. Urinary thiosulfate levels were measured using a high-performance liquid chromatography system.

RESULTS

The upslope of StO₂ was significantly faster after AGE (1.01 ± 0.37% s^-1) intake compared to PLA (0.83 ± 0.35% s^-1; P < 0.001; d = 0.50). Relative changes in Δ% SBP from pre- to post-AGE intake (- 5.17 ± 5.77%) was significantly different compared to Δ% PLA (0.32 ± 5.99%; P = 0.001; d = 0.93). No significant changes in urinary thiosulfate concentrations were observed between interventions. Moreover, no significant gender effect in any parameter assessed was found.

CONCLUSION

This study demonstrated that a single dose of AGE improved microvascular reactivity in older adults at risk of CVD despite such an effect was not linked with urinary thiosulfate levels. This trial was registered at clinicaltrials.gov as NCT04008693 (May 19, 2020).

Vegetable wastes as a bio-additive for low-salt preservation of raw goat skin: An attempt to reduce salinity in leather manufacture

Preservation or curing of hides/skins is performed as the primary step of leather processing to conserve them from putrefaction. Normally preservation is carried out using common salt (NaCl), which is discharged in the soak liquor contributing to ~ 70%, of total dissolved solids (TDS) load of entire leather manufacturing. In an attempt to reduce the TDS and chlorides, phyto-based preservation using garlic peel (Allium sativum) and white onion peel (Allium cepa) was carried out. Different concentrations of salt in combination with garlic peel and white onion peel were applied on freshly flayed goat skins based on its green weight and compared to control (40% salt). Sensory evaluation of the preserved skin was done by assessing different parameters like hair slip, putrefaction and odour. Estimation of hydroxyproline (HP) release, moisture content and microbial load were carried out at regular intervals. Skins that remained in good condition for 14 days were further processed into leather and properties were examined which were found comparable to the conventionally cured skins. Hence, this cleaner curing technique helps in reducing the TDS and chlorides in the effluent, thus controlling the pollution caused by tanneries through sustainable leather processing.

Effects of colonic fermentation on the stability of fresh and black onion bioactives

The health properties related to onion intake are attributed mainly to the presence of bioactive compounds, particularly phenolic and organosulfur compounds (OSCs). The aim of this study was to investigate, for the first time, the effect of an in vitro colonic fermentation on the stability of phenolic and OSCs of fresh and black onion by ultra-high-performance liquid chromatography coupled with mass spectrometry with a linear ion trap (UHPLC-LIT-MS). Throughout colonic fermentation, fresh onion showed an increase in the total phenolic content of 45%, mainly due to an increase in the content of the flavonoid family, while the OSCs remained stable along the fermentation. Black onion presented a different behaviour, showing significant decreases in total (poly)phenol and OSC content, 22 and 48%, respectively. The main compounds found after the in vitro colonic fermentation of fresh onion were isorhamnetin (141 μmol L^-1), quercetin (95 μmol L^-1), 3,4-dihydroxybenzoic acid (53 μmol L^-1), methionine sulfoxide (100 μmol L^-1) and S-allylcysteine (SAC) (21.7 μmol L^-1), whereas 3,4-dihydroxybenzoic acid (70 μmol L^-1), 4-hydroxyphenylacetic acid (68 μmol L^-1), methionine sulfoxide (82 μmol L^-1) and S-propylmercapto-L-cysteine (SPMC) (10.1 μmol L^-1) accounted for the highest concentrations of phenolics and OSCs in fermented black onion. These compounds, presumably present for their absorption and action at the colonic level, could be related to the health benefits of regular consumption of fresh and black onion.

In Vitro Colonic Fermentation of (Poly)phenols and Organosulfur Compounds of Fresh and Black Garlic

The beneficial properties associated with garlic consumption have been related to the presence of bioactive compounds including (poly)phenols and organosulfur compounds (OSCs). This study aims to assess the effect of in vitro colonic fermentation on fresh and black garlic by determining the transformation of these compounds through ultrahigh-performance liquid chromatography coupled to mass spectrometry with a linear ion trap (uHPLC-LIT-MS). Colonic fermentation had a similar influence on the phenolic content of fresh and black garlic, with total respective decreases of 43.8% and 41.7%. Meanwhile, fermentation resulted in a significant decrease (33%) in OSCs in black garlic. Compounds such as 4-hydroxybenzoic acid, S-allylcysteine (SAC), and methionine sulfoxide were the phenolic compounds and OSCs with the highest concentration in fresh and black garlic after the in vitro fermentation. These compounds, potentially present at the colonic level, might be responsible for the systemic health benefits associated with the consumption of black and fresh garlic.

S-Allyl cysteine in garlic (Allium sativum): Formation, biofunction, and resistance to food processing for value-added product development

S-allyl cysteine (SAC), which is the most abundant bioactive compound in black garlic (BG; Allium sativum), has been shown to have antioxidant, anti-apoptotic, anti-inflammatory, anti-obesity, cardioprotective, neuroprotective, and hepatoprotective activities. Sulfur compounds are the most distinctive bioactive elements in garlic. Previous studies have provided evidence that the concentration of SAC in fresh garlic is in the range of 19.0-1736.3 μg/g. Meanwhile, for processed garlic, such as frozen and thawed garlic, pickled garlic, fermented garlic extract, and BG, the SAC content increased to up to 8021.2 μg/g. BG is an SAC-containing product, with heat treatment being used in nearly all methods of BG production. Therefore, strategies to increase the SAC level in garlic are of great interest; however, further knowledge is required about the effect of processing factors and mechanistic changes. This review explains the formation of SAC in garlic, introduces its biological effects, and summarizes the recent advances in processing methods that can affect SAC levels in garlic, including heat treatment, enzymatic treatment, freezing, fermentation, ultrasonic treatment, and high hydrostatic pressure. Thus, the aim of this review was to summarize the outcomes of treatment aimed at maintaining or increasing SAC levels in BG. Therefore, publications from scientific databases in this field of study were examined. The effects of processing methods on SAC compounds were evaluated on the basis of the SAC content. This review provides information on the processing approaches that can assist food manufacturers in the development of value-added garlic products.

Biophysical, Biochemical, and Molecular Docking Investigations of Anti-Glycating, Antioxidant, and Protein Structural Stability Potential of Garlic

Garlic has been reported to inhibit protein glycation, a process that underlies several disease processes, including chronic complications of diabetes mellitus. Biophysical, biochemical, and molecular docking investigations were conducted to assess anti-glycating, antioxidant, and protein structural protection activities of garlic. Results from spectral (UV and fluorescence) and circular dichroism (CD) analysis helped ascertain protein conformation and secondary structure protection against glycation to a significant extent. Further, garlic showed heat-induced protein denaturation inhibition activity (52.17%). It also inhibited glycation, advanced glycation end products (AGEs) formation as well as lent human serum albumin (HSA) protein structural stability, as revealed by reduction in browning intensity (65.23%), decrease in protein aggregation index (67.77%), and overall reduction in cross amyloid structure formation (33.26%) compared with positive controls (100%). The significant antioxidant nature of garlic was revealed by FRAP assay (58.23%) and DPPH assay (66.18%). Using molecular docking analysis, some of the important garlic metabolites were investigated for their interactions with the HSA molecule. Molecular docking analysis showed quercetin, a phenolic compound present in garlic, appears to be the most promising inhibitor of glucose interaction with the HSA molecule. Our findings show that garlic can prevent oxidative stress and glycation-induced biomolecular damage and that it can potentially be used in the treatment of several health conditions, including diabetes and other inflammatory diseases.

S-allylcysteine Ameliorates Aging Features Via Regulating Mitochondrial Dynamics in Naturally Aged C57BL/6J Mice

SCOPE

S-allylcysteine (SAC) is the most abundant organosulfur molecule derived from aged garlic. We evaluated the effects of S-allylcysteine (SAC) on improving aging in naturally aged C57BL/6J male mice and mitochondrial dynamics in C. elegans and its underlying mechanisms.

METHODS AND RESULTS

When mice had attained reproductive senescence at 60 weeks of age, SAC was supplemented to 0.05% and 0.2% into their normal diet for 12 weeks The results showed that SAC could significantly improve the level of hepatic OPA1 mRNA, which is a key factor for mitochondrial fusion, and consequently elevated the mitochondrial biogenesis-related proteins SIRT1 and PGC-1α, thus ameliorating oxidative stress, such as MDA in the liver and 8-OHdG in urine. Among the biochemical markers of aging, SAC significantly reduced liver GLB1 and SA-βgal, which were induced by replicative senescence. The mitochondria with GFP-tagged transgenic strain SJ4103 C. elegans was incubated with 5 or 50 μM SAC, and SAC treated groups maintained the linear morphology of mitochondria.

CONCLUSION

SAC regulated mitochondrial dynamics and ameliorated aging to a significant degree. This study also confirmed that mitochondrial dynamics are a promising target for screening materials to combat aging and as a direction for anti-aging product development. This article is protected by copyright. All rights reserved.

Unravelling the Immune Modulatory Effect of Indian Spices to Impede the Transmission of COVID-19: A Promising Approach

Months after WHO declared COVID-19 as a Global Public Health Emergency of International Concern, it does not seem to be flattening the curve as we are still devoid of an effective treatment modality and vaccination is in the first phase in many countries. Amid such uncertainty, being immune is the best strategy to defend against corona attacks. As the whole world is referring back to immune-boosting traditional remedies, interest is rekindled in the Indian system of Medicine, which is gifted with an abundance of herbal medicines as well as remedies. Among them, spices (root, rhizome, seed, fruit, leaf, bud, and flower of various plants used to add taste and flavors to food) are bestowed with immense medicinal potential. A plethora of clinical as well as preclinical studies reported the effectiveness of various spices for various ailments. The potential immune-boosting properties together with their excellent safety profiles are making spices the current choice of phytoresearch as well as the immune-boosting home remedies during these sceptical times. The present review critically evaluates the immune impact of various Indian spices and their potential to tackle the novel coronavirus, with comments on the safety and toxicity aspects of spices.

Immunomodulatory effects of Allium Sativum L. and its constituents against viral infections and metabolic diseases

BACKGROUND

Allium sativum L., or garlic, is one of the most studied plants worldwide within the field of traditional medicine. Current interests lie in the potential use of garlic as a preventive measure and adjuvant treatment for viral infections, e.g., SARS-CoV-2. Even though it cannot be presented as a single treatment, its beneficial effects are beyond doubt. The World Health Organization has deemed it an essential part of any balanced diet with immunomodulatory properties.

OBJECTIVE

The aim of the study was to review the literature on the effects of garlic compounds and preparations on immunomodulation and viral infection management, with emphasis on SARS-CoV-2.

METHOD

Exhaustive literature search has been carried out on electronic databases.

CONCLUSION

Garlic is a fundamental part of a well-balanced diet which helps maintain general good health. The reported information regarding garlic's ability to beneficially modulate inflammation and the immune system is encouraging. Nonetheless, more efforts must be made to understand the actual medicinal properties and mechanisms of action of the compounds found in this plant to inhibit or diminish viral infections, particularly SARS-CoV-2. Based on our findings, we propose a series of innovative strategies to achieve such a challenge in the near future.

Chemical Constituents, In Vitro Antioxidant Activity and In Silico Study on NADPH Oxidase of Allium sativum L. (Garlic) Essential Oil

Allium sativum L., also known as garlic, is a perennial plant widely used as a spice and also considered a medicinal herb since antiquity. The aim of this study was to determine by gas chromatography-mass spectrometry (GC-MS) the chemical profile fingerprint of the essential oil (EO) of one accession of Peruvian A. sativum (garlic), to evaluate its antioxidant activity and an in- silico study on NADPH oxidase activity of the volatile phytoconstituents. The antioxidant activity was tested using DPPH and β-carotene assays. An in-silico study was carried out on NADPH oxidase (PDB ID: 2CDU), as was ADMET prediction. The results indicated that diallyl trisulfide (44.21%) is the major component of the EO, followed by diallyl disulfide (22.08%), allyl methyl trisulfide (9.72%), 2-vinyl-4H-1,3-dithiine (4.78%), and α-bisabolol (3.32%). Furthermore, the EO showed antioxidant activity against DPPH radical (IC50 = 124.60 ± 2.3 µg/mL) and β-carotene bleaching (IC50 = 328.51 ± 2.0). The best docking score on NADPH oxidase corresponds to α-bisabolol (ΔG = -10.62 kcal/mol), followed by 5-methyl-1,2,3,4-tetrathiane (ΔG = -9.33 kcal/mol). Additionally, the volatile components could be linked to the observed antioxidant activity, leading to potential inhibitors of NADPH oxidase.

The effect and underlying mechanisms of garlic extract against cognitive impairment and Alzheimer's disease: A systematic review and meta-analysis of experimental animal studies

ETHNOPHARMACOLOGICAL RELEVANCE

Alzheimer's disease (AD) is the main cause of dementia, and according to traditional Chinese medicine (TCM), it is leaded by the deficiency of essence, qi, and blood. Allii sativi bulbus, acrid and warm, is traditionally used as the important adjuvant and conductant drug to distribute essence-qi throughout the body, fortify the spleen and harmonize the stomach. Garlic (Allium sativum L., Alliaceae) has also been reported to display potential anti-AD effect both in vitro and in vivo studies, while no systematic review of these studies has been conducted.

AIM OF THE STUDY

This review aims to provide a comprehensive evaluation of the effect and underlying mechanism of garlic extract against cognitive impairment and AD neuropathology through meta-analysis and sensitivity analysis.

MATERIALS AND METHODS

Eligible studies were searched from PubMed, Web of Science and EMBASE from February to March in 2020, and 13 studies describing the effect of garlic extract in AD animal models (551 mice and 88 rats) were identified.

RESULTS

Analysis of these studies showed that garlic extract could reduce cerebral Aβ levels [Aβ₄₀: SMD -8.62(-11.75, -5.49), p < 0.00001 and Aβ₄₂: SMD -11.70(-18.01, -5.39), p=0.0003], and increase the number of right crossings in MWM [SMD 2.87(1.48, 4.26), p < 0.0001] in AD animals. However, moderate risk of bias (quality score ranged from 40% to 60%) is revealed by SYRCLE's checklist, mainly because of the lacks of sample size calculation, random allocation and blind assessment.

CONCLUSIONS

This review shows that garlic extract may be effective in alleviating cognitive impairment and neuropathology in AD animal models. High quality AD animal studies with enough sample size and more comprehensive evaluation of outcomes are needed to further confirm the results.

Garlic (Allium sativum L.): Its Chemistry, Nutritional Composition, Toxicity and Anticancer Properties

The current review discuss the chemistry, nutritional composition, toxicity, and biological functions of garlic and its bioactive compounds against various types of cancers via different anticancer mechanisms. Several scientific documents were found in reliable literature and searched in databases viz Science Direct, PubMed, Web of Science, Scopus and Research Gate were carried out using keywords such as "garlic", "garlic bioactive compounds", "anticancer mechanisms of garlic", "nutritional composition of garlic", and others. Garlic contains several phytoconstituents with activities against cancer, and these compounds such as diallyl trisulfide (DATS), allicin, and diallyl disulfide (DADS), diallyl sulfide (DAS), and allyl mercaptan (AM). The influence of numerous garlic-derived products, phytochemicals, and nanoformulations on the liver, oral, prostate, breast, gastric, colorectal, skin, and pancreatic cancers has been studied. Based on our search, the bioactive molecules in garlic were found to inhibit the various phases of cancer. Moreover, the compounds in this plant also abrogate the peroxidation of lipids, activity of nitric oxide synthase, epidermal growth factor (EGF) receptor, nuclear factor-kappa B (NF-κB), protein kinase C, and regulate cell cycle and survival signaling cascades. Hence, garlic and its bioactive molecules exhibit the aforementioned mechanistic actions and thus, they could be used to inhibit the induction, development and progression of cancer. The review describes the nutritional Composition of garlic, its bioactive molecules, and nanoformulations against various types of cancers, as well as the potential for developing these agents as antitumor drugs.

Translating the advanced glycation end products (AGEs) knowledge into real-world nutrition strategies

Advanced glycation end products (AGEs) are glycated proteins or lipids derived from complex metabolic pathways involved in the pathophysiology of various diseases, especially diabetes and diabetes-related complications. These compounds are omnipresent in human life, with both endogenous and exogenous sources. Despite the well-elucidated disease mechanisms, little is known about the AGEs/nutrition nexus in the circles of clinical practice recommendations. This review seeks to translate the accumulated knowledge about the biochemistry and pathophysiology of AGEs into a nutritional intervention based on real-world prescriptions.

Pharmacotherapeutic Potential of Garlic in Age-Related Neurological Disorders

Age-related neurological disorders [ANDs] involve neurodegenerative diseases [NDDs] such as Alzheimer's disease [AD], the most frequent kind of dementia in elderly people, and Parkinson's disease [PD], and also other disorders like epilepsy and migraine. Although ANDs are multifactorial, Aging is a principal risk factor for them. The common and most main pathologic features among ANDs are inflammation, oxidative stress, and misfolded proteins accumulation. Since failing brains caused by ANDs impose a notable burden on public health and their incidence is increasing, a lot of works has been done to overcome them. Garlic, Allium sativum, has been used for different medical purposes globally and more than thousands of publications have reported its health benefits. Garlic and aged garlic extract are considered potent anti-inflammatory and antioxidants agents and can have remarkable neuroprotective effects. This review is aimed to summarize knowledge on the pharmacotherapeutic potential of garlic and its components in ANDs.

Whole-plant foods and their macromolecules: untapped approaches to modulate neuroinflammation in Alzheimer's disease

Alzheimer's disease (AD) is a progressive neurodegenerative disorder. Recently, sustained neuroinflammatory response in microglia and astrocytes has been found to cause the deposition of amyloid beta plaques and the hyperphosphorylation of tau protein, thereby accelerating AD progression. The lipoxin A4-transcription factor nuclear factor-kappa B and mitogen-activated protein kinase pathways have been shown to play important roles in the regulation of inflammatory processes. There is growing research-based evidence suggesting that dietary whole-plant foods, such as mushrooms and berries, may be used as inhibitors for anti-neuroinflammation. The beneficial effects of whole-plant foods were mainly attributed to their high contents of functional macromolecules including polysaccharides, polyphenols, and bioactive peptides. This review provides up-to-date information on important molecular signaling pathways of neuroinflammation and discusses the anti-neuroinflammatory effects of whole-plant foods. Further, a critical evaluation of plants' macromolecular components that have the potential to prevent and/or relieve AD is provided. This work will contribute to better understanding the pathogenetic mechanism of neuroinflammation in AD and provide new approaches for AD therapy.

Potential Antibacterial Efficacy of Garlic Extract on Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae: An In vitro Study

Background:

Garlic has been recommended by many ancient medicines such as the Chinese and the Indian medicine to cure respiratory and digestive issues along with treating microbial infestation and leprosy. The therapeutic effects encompass many advantages in the field of cardiovascular system, antibiotics, anticancer, anti-inflammatory, and hormone-like effects.

Aims and Objective:

The present study was carried out to evaluate the garlic antibacterial effect against clinical isolates of Staphylococcus aureus, Escherichia coli, and Pneumoniae from patients attending referral hospital.

Materials and Methods:

The isolation of bacteria was done from pus sample collected from referral hospital, Bedar, Karnataka, with sterile swabs. The study samples were inoculated under aseptic conditions on culture media such as nutrient agar, blood agar, and MacConkey agar plates and isolated the pathogen bacteria such as E. coli, Klebsiella pneumoniae, and S. aureus. The garlic bulbs were peeled off and then ligated using pestle simultaneously with addition of minor quantity of H₂O for preparation of plant extract and study the antimicrobial effect of garlic on these bacteria.

Results:

The result showed that garlic extracts have a high range of antibacterial effect against both Gram-negative (E. coli and K. pneumoniae) and Gram-positive bacteria Staphylococcus.

Conclusion:

The present study observations revealed that garlic makes large clear zones in comparison to the currently available antibiotics used in the study. The potentiality of the garlic can be utilized in the field of antibacterial agents. It can be prepared in the form of tablets in the best concentrations and affordable dosages so that it can be used as medicine against these pathogenic organisms.

Improving the bioavailability and bioactivity of garlic bioactive compounds via nanotechnology

This review highlights main bioactive compounds and important biological functions especially anticancer effects of the garlic. In addition, we review current literature on the stability and bioavailability of garlic components. Finally, this review aims to provide a potential strategy for using nanotechnology to increase the stability and solubility of garlic components, providing guidelines for the qualities of garlic products to improve their absorption and prevent their early degradation, and extend their circulation time in the body. The application of nanotechnology to improve the bioavailability and targeting of garlic compounds are expected to provide a theoretical basis for the functional components of garlic to treat human health. We review the improvement of bioavailability and bioactivity of garlic bioactive compounds via nanotechnology, which could promisingly overcome the limitations of conventional garlic products, and would be used to prevent and treat cancer and other diseases in the near future.