Effects of the Gut microbiota on Amygdalin and its use as an anti-cancer therapy: Substantial review on the key components involved in altering dose efficacy and toxicity

Amygdalin and exercise training exert a synergistic effect in improving cardiac performance and ameliorating cardiac inflammation and fibrosis in a rat model of myocardial infarction

This study investigated the effects of amygdalin (AMY, a cyanogenic glycoside widely distributed in the fruits and seeds of Rosaceae plants) on cardiac performance and ventricular remodeling in a rat model of myocardial infarction (MI). We also investigated whether the combination of AMY with exercise training (ExT) has a beneficial synergistic effect in treating MI rats. MI was induced by the ligation of the left anterior descending coronary artery in male SD rats. ExT or AMY treatment was started 1 week after MI and continued for 1 week (short-term) or 8 weeks (long-term). Cardiac function was evaluated by echocardiographic and hemodynamic parameters. Heart tissues were harvested and subjected to 2,3,5-triphenyl-tetrazolium chloride, Masson's trichrome, hematoxylin-eosin, and immunohistochemical staining. Gene expression was determined by quantitative polymerase chain reaction. Western blot gave a qualitative assessment of protein levels. AMY or ExT improved cardiac function and reduced infarct size in MI rats. AMY or ExT also suppressed myocardial fibrosis and attenuated inflammation in the infarct border zone of hearts from MI rats, as evidenced by inhibition of collagen deposition, inflammatory cell infiltration, and pro-inflammatory markers (interleukin 1β, interleukin 6, tumor necrosis factor-α, and cyclooxygenase 2). Notably, the effects of AMY combined with ExT were superior to those of AMY alone or ExT alone. Mechanistically, these beneficial functions were correlated with the inhibition of MI-induced activation of the transforming growth factor-β/Smad pathway. Collectively, AMY and ExT exert a synergistic effect on improving cardiac performance and ameliorating cardiac inflammation and fibrosis after MI, and the effects of long-term intervention were better than short-term intervention.

Unravelling the Untapped Pharmacological Potential of Plant Molecules as Inhibitors of BACE1: In Silico Explorations for Alzheimer's Disease

Alzheimer's disease (AD) is an extremely complex, heterogeneous, and multifactorial neurodegenerative disease clinically characterized by progressive memory loss and progressive decline in cognitive function. There is currently no effective treatment for the onset and/or progression of the pathophysiological diseases of AD. The global prevalence of this disease has increased in recent years due to modern lifestyle. Therefore, there is an urgent need to develop a drug with significant neuroprotective potential. Since plant metabolites, especially polyphenols, have important pharmacological properties acting against β-amyloid (Aβ), Tau, neuroinflammation, and oxidative stress, such phytochemicals were selected in the present research. Using the Schrödinger tool (Maestro V.13.6), the drug potency of these metabolites was studied after installation in the highly configured workstation. Among the 120 polyphenols docked, amygdalin showed notable docking values of - 11.2638, followed by eriocitrin (- 10.9569), keracyanin (- 10.7086), and amaroswerin (- 9.48126). The prominent MM-GBSA values of these molecules were - 62.8829, - 52.1914, - 68.6307, and - 63.1074, respectively. The MM-GBSA energy values demonstrated the drug stability of these molecules for β-site amyloid precursor protein-cleaving enzyme 1 (BACE1)-causing AD. In the absorption and distribution assessment, these phytochemicals showed significantly better values than the inhibitors CNP520. The chosen phytochemicals have been demonstrated as non-hepatotoxic; however, the BACE1 inhibitor CNP520 is hepatotoxic. In both the molecular docking and ADMET assessments, these natural chemicals have shown optimism as potential drug candidates for Alzheimer's disease. However, in order to understand the detailed biological metabolism of these compounds in AD, they need to be evaluated in in vivo studies to validate its efficacy.

Amygdalin Delays Cartilage Endplate Degeneration and Improves Intervertebral Disc Degeneration by Inhibiting NF-κB Signaling Pathway and Inflammatory Response

Background

Intervertebral disc degeneration (IDD) is a major cause of lower back pain (LBP), in which inflammatory is frequently involved. Amygdalin (AMD) is a naturally occurring compound that exerts anti-fibrotic, anti-inflammatory, analgesic, and immunomodulatory effects in various diseases. The purpose of this study was to investigate the therapeutic effects and molecular mechanisms of AMD on Lumbar spine instability (LSI)-induced IDD in mice.

Methods

In this study, we first explored the effects of AMD in vivo, and then further explored the mechanism of its effects both in vivo and in vitro. Ten-week-old male C57BL/6J mice were administrated with AMD. At 10 weeks after LSI, spinal were collected for tissue analyses, including histology, micro-CT, and immunohistochemistry for Col2, Mmp-13, TNF-α, and p-P65. Additionally, we also evaluated the mRNA and protein expression level of p-P65 and p-IKBα after being treated with AMD in vitro.

Results

Histological staining, micro-CT and immunohistochemical analysis showed that AMD treatment significantly inhibited the expression of TNF-α and Mmp-13, increased the expression of Col2 as well as attenuated the calcification of cartilage endplates, eventually to delayed the progression of IDD. Meanwhile, in vivo and in vitro fluorescence imaging revealed that AMD markedly inhibited the AMD significantly inhibited the LSI-induced increase in TNF-α expression and P65and IKBα phosphorylation.

Discussion

Our findings suggest that AMD partly inhibits the activation of NF-κB signaling pathway to reduce the release of inflammatory mediators and delay the degeneration of cartilage endplate in IDD model mice. Therefore, AMD may be a potential candidate for the treatment of IDD.

Onco-immunity and therapeutic application of amygdalin: A review

Background

Amygdalin is known as a chemical compound derived from various fruits. The glycosides existing in this plant have been historically utilized as an anticancer agent. This review presented an overview of amygdalin and its onco-immunity and other therapeutic medical applications.

Method

A literature search for studies relating to amygdalin and cancer treatment was carried out using PubMed and Google Scholar. Combinations of the following terms were used in the search strategies: "amygdalin," "rhodanese," "cyanide," "cyanogenic," "hypothiocyanite," "mandelonitrile," "glucosides," "cancer," "apoptosis," and "cytotoxicity," combined with a cancer term such as "seed," "almond," or "apricot," "cancer + cell line, antiproliferation or inhibition," "BAX From the March 3, 1981 until the April 15, 2021, all of the English-language papers were evaluated based on the inclusion criteria. Publications included reviews, chapters from books, and original research papers.

Results

The FDA prohibits Amygdalin from medical usage as an anticancer treatment due to a lack of proof of cure in cancer cases. When this natural-based compound is used with conditional chemotherapeutic medicines causes synergistic effects. Besides, amygdalin is used to manage asthma, improve the immune system, induce apoptosis in human renal fibroblasts, and inhibit hyperglycemia.

Conclusion

Various medical uses of amygdalin have been found such as managing asthma, improving the immune system, inducing apoptosis in human renal fibroblasts, and inhibiting hyperglycemia. More effective in vitro and review studies are required to elucidate the exact role of this herb in medical applications.

Host-microbiome metabolism of a plant toxin in bees

While foraging for nectar and pollen, bees are exposed to a myriad of xenobiotics, including plant metabolites, which may exert a wide range of effects on their health. Although the bee genome encodes enzymes that help in the metabolism of xenobiotics, it has lower detoxification gene diversity than the genomes of other insects. Therefore, bees may rely on other components that shape their physiology, such as the microbiota, to degrade potentially toxic molecules. In this study, we show that amygdalin, a cyanogenic glycoside found in honey bee-pollinated almond trees, can be metabolized by both bees and members of the gut microbiota. In microbiota-deprived bees, amygdalin is degraded into prunasin, leading to prunasin accumulation in the midgut and hindgut. In microbiota-colonized bees, on the other hand, amygdalin is degraded even further, and prunasin does not accumulate in the gut, suggesting that the microbiota contribute to the full degradation of amygdalin into hydrogen cyanide. In vitro experiments demonstrated that amygdalin degradation by bee gut bacteria is strain-specific and not characteristic of a particular genus or species. We found strains of Bifidobacterium, Bombilactobacillus, and Gilliamella that can degrade amygdalin. The degradation mechanism appears to vary since only some strains produce prunasin as an intermediate. Finally, we investigated the basis of degradation in Bifidobacterium wkB204, a strain that fully degrades amygdalin. We found overexpression and secretion of several carbohydrate-degrading enzymes, including one in glycoside hydrolase family 3 (GH3). We expressed this GH3 in Escherichia coli and detected prunasin as a byproduct when cell lysates were cultured with amygdalin, supporting its contribution to amygdalin degradation. These findings demonstrate that both host and microbiota can act together to metabolize dietary plant metabolites.

Amygdalin: A Review on Its Characteristics, Antioxidant Potential, Gastrointestinal Microbiota Intervention, Anticancer Therapeutic and Mechanisms, Toxicity, and Encapsulation

Bioactive amygdalin, found in high concentrations in bitter almonds, has been recognized as a symbol of the cyanogenic glycoside chemical organic substance, which was initially developed as a pharmaceutical for treating cancer after being hydrolyzed to hydrogen cyanide (HCN). Regrettably, research has shown that HCN can also damage normal cells, rendering it non-toxic to the human body. Extreme controversy surrounds both in vivo and in vitro studies, making its use risky. This review provides an extensive update on characteristics, antioxidant potential, gastrointestinal microbiota intervention, anticancer therapeutic, mechanisms, toxicity, and encapsulation of amygdalin. Antioxidant, anti-tumor, anti-fibrotic, antiatherosclerosis, anti-inflammatory, immunomodulatory, and analgesic characteristics, and the ability to improve digestive and reproductive systems, neurodegeneration, and cardiac hypertrophy are just some of the benefits of amygdalin. Studies verified the HCN-produced amygdalin to be harmful orally, but only at very high doses. Although intravenous treatment was less effective than the oral method, the oral route has a dose range of 0.6 to 1 g daily. Amygdalin’s toxicity depends heavily on the variety of bacteria in the digestive tract. Unfortunately, there is currently no foolproof method for determining the microbial consortium and providing a safe oral dosage for every patient. Amygdalin encapsulation in alginate-chitosan nanoparticles (ACNPs) is a relatively new area of research. Amygdalin has an enhanced cytotoxic effect on malignant cells, and ACNPs can be employed as an active drug-delivery system to release this compound in a regulated, sustained manner without causing any harm to healthy cells or tissues. In conclusion, a large area of research for a substance that might be the next step in cancer therapy is opened up due to unverified and conflicting data.

Chinese herbal medicine is associated with higher body weight reduction than liraglutide among the obese population: A real-world comparative cohort study

Introduction: In Taiwan, many people receive Chinese herbal medicine (CHM) as an alternative choice to help control body weight. However, the clinical effectiveness of CHM on weight control has not been well studied, while potential risks and adverse effects are still unknown. The aim of our study is to find out a safe and efficient treatment model of CHM for weight control compared to liraglutide in a real-world setting.

Methods: we retrospectively analyzed obese subjects [body mass index (BMI)≧25 kg/m2] from Chang Gung Research Database (2013–2018). We evaluated the effect on body weight and BMI changes in obese groups receiving CHM or western medicine (WM, represented liraglutide) within 180 days. The proportion of subjects who achieved 5 and 10% weight reduction was calculated as well. Furthermore, the potential adverse events were analyzed during the study period. Overlap weighting was used to balance the baseline differences between CHM and WM groups.

Results: The full cohort comprised 1,360 participants: 701 in the CHM group and 659 in the WM group. At baseline, the CHM group was younger (42.75 ± 12.12 years old in CHM vs. 52.31 ± 11.7 years old in WM, p-value <0.001) and has more female subjects (77.6% in CHM vs. 53.0% in WM, p-value <0.001). On the other hand, CHM users had lower body weight (79.83 ± 15.66 kg vs. 84.68 ± 17.14 kg, p-value <0.001) and BMI (30.58 ± 5.20 vs. 32.84 ± 6.95, p-value <0.001). At day 180, CHM users lost more body weight (−4.5 ± 4.07 kg vs. −2.15 ± 4.05 kg, p-value <0.001) and higher reduction in BMI (−1.77 ± 1.73 vs. −0.9 ± 2.14, p-value <0.001). A total of 53.21% (n = 373) CHM users lost at least 5% of body weight (22.46% for WM users, p-value <0.001), and 18.97% (n = 132) lost at least 10% of body weight (4.55% for WM users, p-value <0.001). The benefit remained consistent with and without overlap weighting. For adverse events, 18 cases of hypertension occurred in 659 subjects in the WM group (2.7%) in comparison to 1 of 701 subjects in the CHM group (0.1%).

Conclusion: CHM led to clinically meaningful weight loss without serious adverse events in a real-world setting. Further clinical trials are warranted to validate this result.

Apricot Kernel: Bioactivity, Characterization, Applications, and Health Attributes

Apricot kernel, a by-product of apricot fruit, is a rich source of proteins, vitamins, and carbohydrates. Moreover, it can be used for medicinal purposes and the formation of food ingredients. Several techniques have been adopted for the extraction of bioactive compounds from the apricot kernel such as solvent extraction, ultra-sonication, enzyme-assisted, microwave-assisted, and aqueous extraction. Apricot kernels may help to fight against various diseases such as cancer and cancer immunotherapy, as well as reduce blood pressure. Additionally, the kernel is famous due to its diverse industrial applications in various industries and fields of research such as thermal energy storage, the cosmetic industry, the pharmaceutical industry, and the food industry. Especially in the food industry, the apricot kernel can be used in the preparation of low-fat biscuits, cookies, cakes, and the fabrication of antimicrobial films. Therefore, in this review article, the bioactivity of the apricot kernel is discussed along with its chemical or nutritional composition, characterizations, and applications.

In Vivo Growth Inhibition of Human Caucasian Prostate Adenocarcinoma in Nude Mice Induced by Amygdalin with Metabolic Enzyme Combinations

Cancer of the prostate is an indicated type that is often recorded as a kind of cancer in men and the second critical cause of mortality through cancer cases. Many pharmacological investigations have shown that numerous herbal substances possess anticancer action. Amygdalin (AMD) has antitumour capabilities and works as an antioxidant, antibacterial, anti-inflammatory, and immune-regulating characteristics. The anticancer effects of amygdalin and its metabolizing enzymes, rhodanese (RHD) and betaglucosidase (BGD), were examined in vivo, as well as their antitumour processes. Novel, effective combination agents are necessary to increase existing cancer treatment rates. This research was aimed at determining the anticarcinogenic impact of amygdalin (AMD) in vivo. This research was aimed at determining the RHD and BGD on the anticarcinogenic impact of AMD in vivo. Subcutaneously, PC3 prostate cancer cell lines were implanted into nude mice. Mice were treated every day with 0.5 ml of 50 mg/ml (AMD), AMD+ (RHD 0.1 mg/ml), AMD+(BGD 0.1 mg/ml), and doxorubicin (DOX 50 mg/ml). Mice were normalized for negative control with untreated mice. In in vivo, morphopathological alterations in the tumour tissue were analyzed by histopathological staining methods. After 35 days of therapy, tumour growth and size inhibition were evident, indicating a function for the metabolic enzymes BGD and RHD in regulating AMD's anticancer effect in vivo. We concluded the critical role of metabolic enzymes BGD and RHD in elevating the antigrowth of PC3 cancer cell lines in Balb/c nude mice treated with AMD.

Impact of Drug Metabolism/Pharmacokinetics and their Relevance Upon Traditional Medicine-based anti-COVID-19 Drug Research

BACKGROUND

The representative anti-COVID-19 herbs, i.e. Poria cocos, Pogostemon, Prunus, and Glycyrrhiza plants, are commonly used in the prevention and treatment of COVID-19, a pandemic caused by SARS-CoV-2. Diverse medicinal compounds with favorable anti-COVID-19 activities are abundant in these plants, and their unique pharmacological/pharmacokinetic properties are being revealed. However, the current trends of drug metabolism/pharmacokinetic (DMPK) investigations of anti-COVID-19 herbs have not been systematically summarized.

METHODS

Here, the latest awareness, as well as the perception gaps of DMPK attributes, in the anti-COVID-19 drug development and clinical usage was elaborated and critically commented.

RESULTS

The extracts and compounds of P. cocos, Pogostemon, Prunus, and Glycyrrhiza plants show distinct and diverse absorption, distribution, metabolism, excretion and toxicity (ADME/T) properties. The complicated herb-herb interactions (HHIs) and herb-drug interactions (HDIs) of anti-COVID-19 Traditional Chinese Medicine (TCM) herb pair/formula dramatically influence the PK/pharmacodynamic (PD) performance of compounds thereof, which may inspire researchers to design innovative herbal/compound formulas for optimizing the therapeutic outcome of COVID-19 and related epidemic diseases. The ADME/T of some abundant compounds in anti-COVID-19 plants have been elucidated, but DMPK studies should be extended to more compounds of different medicinal parts, species and formulations, and would be facilitated by various omics platforms and computational analyses.

CONCLUSION

In the framework of systems pharmacology and pharmacophylogeny, the DMPK knowledge base would promote the translation of bench findings into the clinical practice of anti-COVID-19, and speed up the anti-COVID-19 drug discovery and development.

Investigation of the effect of Prunus Amygdalus Amara on the expression of some genes of apoptosis and immortality in breast cancer cells (MCF-7)

BACKGROUND

Anti-cancer effects of almond nuts or oil have been approved, but there are a few pieces of research that have evaluated, in detail, almond and other seeds' effects on cancer. Therefore, in the present project, the aim was to explore the regulatory effect of the bitter almond extract (Prunus amygdalus Batsch) on the apoptotic and anti-cancer potency of MCF-7 cells.

OBJECTIVES

In the current experimental research, the Almond effect on MCF7 cells was evaluated by investigating the expression and the balance between Bcl-2, Bax genes to unmark the potential molecular mechanism.

METHODS

For 24 and 48h, the MCF7 cells were treated with the bitter almond extract (187.5-3000 µg/mL). MTT assay was used to assess the viability, and Real-time-PCR was applied to determine the expression of Bax and Bcl-2, facing β-actin.

RESULTS

Our results revealed a significant difference between different extract concentrations on the viability of MCF7 cell lines in 24 and 48 h; cell viability decreased time-dependently (P < 0.05). After 24 and 48h of extract facing MCF7 cells, the evaluated IC50 value was 3000 and 1500 µg/mL, respectively. Based on Real Time-PCR analysis, after 24 and 48 h, the mRNA levels of BCL-2 decreased by the extract, whereas BAX was in the MCF-7 cell line.

CONCLUSION

From the results, it can be concluded that bitter almond extract has anti-cancer properties that may influence the apoptotic pathways by regulating relative gene expression.

Sulfur Administration in Fe-S Cluster Homeostasis

Mitochondria are the key organelles of Fe–S cluster synthesis. They contain the enzyme cysteine desulfurase, a scaffold protein, iron and electron donors, and specific chaperons all required for the formation of Fe–S clusters. The newly formed cluster can be utilized by mitochondrial Fe–S protein synthesis or undergo further transformation. Mitochondrial Fe–S cluster biogenesis components are required in the cytosolic iron–sulfur cluster assembly machinery for cytosolic and nuclear cluster supplies. Clusters that are the key components of Fe–S proteins are vulnerable and prone to degradation whenever exposed to oxidative stress. However, once degraded, the Fe–S cluster can be resynthesized or repaired. It has been proposed that sulfurtransferases, rhodanese, and 3-mercaptopyruvate sulfurtransferase, responsible for sulfur transfer from donor to nucleophilic acceptor, are involved in the Fe–S cluster formation, maturation, or reconstitution. In the present paper, we attempt to sum up our knowledge on the involvement of sulfurtransferases not only in sulfur administration but also in the Fe–S cluster formation in mammals and yeasts, and on reconstitution-damaged cluster or restoration of enzyme’s attenuated activity.

Inflammation, It's Regulation and Antiphlogistic Effect of the Cyanogenic Glycoside Amygdalin

The inflammatory reaction accompanies in part or in full any disease process in the vascularized metazoan. This complicated reaction is controlled by regulatory mechanisms, some of which produce unpleasant symptomatic manifestations of inflammation. Therefore, there has been an effort to develop selective drugs aimed at removing pain, fever, or swelling. Gradually, however, serious adverse side effects of such inhibitors became apparent. Scientific research has therefore continued to explore new possibilities, including naturally available substances. Amygdalin is a cyanogenic glycoside present, e.g., in bitter almonds. This glycoside has already sparked many discussions among scientists, especially about its anticancer potential and related toxic cyanides. However, toxicity at different doses made it generally unacceptable. Although amygdalin given at the correct oral dose may not lead to poisoning, it has not yet been accurately quantified, as its action is often affected by different intestinal microbial consortia. Its pharmacological activities have been studied, but its effects on the body's inflammatory response are lacking. This review discusses the chemical structure, toxicity, and current knowledge of the molecular mechanism of amygdalin activity on immune functions, including the anti-inflammatory effect, but also discusses inflammation as such, its mediators with diverse functions, which are usually targeted by drugs.

The influence of the gut microbiome on BCG-induced trained immunity

BACKGROUND

The bacillus Calmette-Guérin (BCG) vaccine protects against tuberculosis and heterologous infections but elicits high inter-individual variation in specific and nonspecific, or trained, immune responses. While the gut microbiome is increasingly recognized as an important modulator of vaccine responses and immunity in general, its potential role in BCG-induced protection is largely unknown.

RESULTS

Stool and blood were collected from 321 healthy adults before BCG vaccination, followed by blood sampling after 2 weeks and 3 months. Metagenomics based on de novo genome assembly reveals 43 immunomodulatory taxa. The nonspecific, trained immune response is detected by altered production of cytokines IL-6, IL-1β, and TNF-α upon ex vivo blood restimulation with Staphylococcus aureus and negatively correlates with abundance of Roseburia. The specific response, measured by IFN-γ production upon Mycobacterium tuberculosis stimulation, is associated positively with Ruminococcus and Eggerthella lenta. The identified immunomodulatory taxa also have the strongest effects on circulating metabolites, with Roseburia affecting phenylalanine metabolism. This is corroborated by abundances of relevant enzymes, suggesting alternate phenylalanine metabolism modules are activated in a Roseburia species-dependent manner.

CONCLUSIONS

Variability in cytokine production after BCG vaccination is associated with the abundance of microbial genomes, which in turn affect or produce metabolites in circulation. Roseburia is found to alter both trained immune responses and phenylalanine metabolism, revealing microbes and microbial products that may alter BCG-induced immunity. Together, our findings contribute to the understanding of specific and trained immune responses after BCG vaccination.

The gut microbiome in konzo

Konzo, a distinct upper motor neuron disease associated with a cyanogenic diet and chronic malnutrition, predominately affects children and women of childbearing age in sub-Saharan Africa. While the exact biological mechanisms that cause this disease have largely remained elusive, host-genetics and environmental components such as the gut microbiome have been implicated. Using a large study population of 180 individuals from the Democratic Republic of the Congo, where konzo is most frequent, we investigate how the structure of the gut microbiome varied across geographical contexts, as well as provide the first insight into the gut flora of children affected with this debilitating disease using shotgun metagenomic sequencing. Our findings indicate that the gut microbiome structure is highly variable depending on region of sampling, but most interestingly, we identify unique enrichments of bacterial species and functional pathways that potentially modulate the susceptibility of konzo in prone regions of the Congo.

The Multiple Actions of Amygdalin on Cellular Processes with an Emphasis on Female Reproduction

The present review summarizes the current knowledge on the provenance and properties, metabolism and toxicity, mechanism of action, physiological, and therapeutic roles of amygdalin-a molecule present in the seeds of apricot and other plants-with an emphasis on the action of amygdalin on reproductive processes, particularly in the female. Amygdalin influences physiological processes including female reproduction at various regulatory levels via extra- and intracellular signaling pathways regulating secretory activity, cell viability, steroidogenesis, proliferation, and apoptosis. On the other hand, while being metabolized in the body, amygdalin releases significant amounts of cyanide, which may lead to acute health hazard in those individuals who may be at risk. Despite some contradictions in the available data about benefits and toxic effects of amygdalin, its potential applicability at low doses may present a promising tool for regulation of various reproductive and other physiological processes including disease management primarily in cancer phytotherapy, animal production, medicine, and biotechnology. However, further research involving carefully designed dose-response studies is required to overcome the possible side effects of amygdalin and assure its safety as a therapeutic agent.

Revalorization of Almond By-Products for the Design of Novel Functional Foods: An Updated Review

The search for waste minimization and the valorization of by-products are key to good management and improved sustainability in the food industry. The great production of almonds, based on their high nutritional value as food, especially almond kernels, generates tons of waste yearly. The remaining parts (skin, shell, hulls, etc.) are still little explored, even though they have been used as fuel by burning or as livestock feed. The interest in these by-products has been increasing, as they possess beneficial properties, caused by the presence of different bioactive compounds, and can be used as promising sources of new ingredients for the food, cosmetic and pharmaceutical industry. Additionally, the use of almond by-products is being increasingly applied for the fortification of already-existing food products, but there are some limitations, including the presence of allergens and mycotoxins that harden their applicability. This review focuses on the extraction technologies applied to the valorization of almond by-products for the development of new value-added products that would contribute to the reduction of environmental impact and an improvement in the sustainability and competitiveness of the almond industry.

Amygdalin promotes the activity of T cells to suppress the progression of HBV-related hepatocellular carcinoma via the JAK2/STAT3 signaling pathway

Background

Hepatitis B virus (HBV) infection is a high-risk factor of hepatocellular carcinoma (HCC). Cellular immune responses are essential for HCC development, and the CD4+ and CD8+ T subtypes are identified as the primary anti-tumor immune cells. In the study, we investigated the effect and mechanism of amygdalin in the cellular immune response in HBV-related HCC and HCC progression.

Methods

The cell proliferation was examined by MTT analysis. Cells metastasis ability was detected by Invasion and migration assays. Quantification of apoptotic cells was performed with Flow cytometer assay. The protein levels of p-STAT3, STAT3, p-JAK2, JAK2, caspase-3, cleaved caspase-3 were detected by performing immunoblotting assays.

Results

We demonstrate that amygdalin treatment could rescue the HBV-T cell viability and IFN-γ and TNF-αproduction. In HBV-T cells, the MFI levels of CD8⁺ are lower than that in NC-T cells. Moreover, the phosphorylation levels of STAT3 and JAK2 are higher in HBV-T cells, compared to those in NC-T cells, and then reduced by amygdalin treatment. Co-culture with HBV-T cells could reduce IFN-γ and TNF-α, production while increase IL-6 and IL-10 production in HepG2.2.15 cells; these alterations could be partially reversed by amygdalin pretreatment. Finally, co-culture with HBV-T cells significantly promoted the cell viability, inhibited the apoptosis, and promoted the migration of HepG2.2.15 cells, and these alterations could be partially reversed by amygdalin treatment.

Conclusion

Our findings provide a rationale for further studies on the functions and mechanism of amygdalin inhibiting HBV-related HCC cell proliferation, invasion, and migration via T cell-mediated tumor immunity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-020-05713-0.

Solubility, Solution Thermodynamics, and Preferential Solvation of Amygdalin in Ethanol + Water Solvent Mixtures

The equilibrium solubility of amygdalin in [ethanol (1) + water (2)] mixtures at 293.15 K to 328.15 K was reported. The thermodynamic properties (standard enthalpy Δ_solnH°, standard entropy Δ_solnS°, and standard Gibbs energy of solution Δ_solnG°) were computed using the generated solubility data via van't Hoff and Gibbs equations. The dissolution process of amygdalin is endothermic and the driving mechanism in all mixtures is entropy. Maximal solubility was achieved in 0.4 mole fraction of ethanol at 328.15 K and the minimal one in neat ethanol at 293.15 K. Van't Hoff, Jouyban-Acree-van't Hoff, and Buchowski-Ksiazczak models were used to simulate the obtained solubility data. The calculated solubilities deviate reasonably from experimental data. Preferential solvation parameters of amygdalin in mixture solvents were analyzed using the inverse Kirkwood-Buff integrals (IKBI) method. Amygdalin is preferentially solvated by water in ethanol-rich mixtures, whereas in water-rich mixtures, there is no clear evidence that determines which of water or ethanol solvents would be most likely to solvate the molecule.

Analysis of Amygdalin in Various Matrices Using Electrospray Ionization and Flowing Atmospheric-Pressure Afterglow Mass Spectrometry

Amygdalin is a natural cyanogenic compound that plants produce in the fight against insects and herbivores. Excessive amounts of amygdalin by animals and humans can potentially lead to fatal intoxication. However, studies confirm that amygdalin has antitumor properties, including the ability to inhibit the proliferation of cancer cells and to induce their apoptosis. The analysis of amygdalin in various matrices is an important analytical problem today. The publication presents the methodology of direct determination of amygdalin in water, sewage, and biological materials using electrospray ionization mass spectrometry (ESI-MS) and a new analytical method using flowing atmospheric-pressure afterglow mass spectrometry (FAPA-MS). The methods of analyte pre-concentration using a magnetic, molecularly imprinted polymer (mag-MIP) and the influence of interferents on the recorded spectra were discussed. Analytical parameters in ESI-MS and FAPA-MS methods were established. The linearity range was 4.5 µg L⁻¹–45 mg L⁻¹ in positive mode ESI-MS and FAPA-MS. The limit of detection (LOD) for ESI-MS was 0.101 ± 0.003 µg L⁻¹ and the limit of quantification (LOQ) was 0.303 ± 0.009 µg L⁻¹. In FAPA-MS, the LOD was 0.050 ± 0.002 µg L⁻¹ and the LOQ was 0.150 ± 0.006 µg L⁻¹. The content of amygdalin in various matrices was determined.

Stone Fruit as Biofactories of Phytochemicals With Potential Roles in Human Nutrition and Health

Phytochemicals or secondary metabolites present in fruit are key components contributing to sensory attributes like aroma, taste, and color. In addition, these compounds improve human nutrition and health. Stone fruits are an important source of an array of secondary metabolites that may reduce the risk of different diseases. The first part of this review is dedicated to the description of the main secondary organic compounds found in plants which include (a) phenolic compounds, (b) terpenoids/isoprenoids, and (c) nitrogen or sulfur containing compounds, and their principal biosynthetic pathways and their regulation in stone fruit. Then, the type and levels of bioactive compounds in different stone fruits of the Rosaceae family such as peach (Prunus persica), plum (P. domestica, P. salicina and P. cerasifera), sweet cherries (P. avium), almond kernels (P. dulcis, syn. P. amygdalus), and apricot (P. armeniaca) are presented. The last part of this review encompasses pre- and postharvest treatments affecting the phytochemical composition in stone fruit. Appropriate management of these factors during pre- and postharvest handling, along with further characterization of phytochemicals and the regulation of their synthesis in different cultivars, could help to increase the levels of these compounds, leading to the future improvement of stone fruit not only to enhance organoleptic characteristics but also to benefit human health.

Genotoxic and antigenotoxic potential of amygdalin on isolated human lymphocytes by the comet assay

Amygdalin is a cyanogenic glycoside, mainly present in the seeds of the Rosaceae family such as apricots, peaches, and bitter almond. In this study, in vitro genotoxic and antigenotoxic effects of amygdalin have been investigated on human peripheral blood lymphocytes using the comet assay. The antigenotoxic effect of amygdalin was performed against hydrogen peroxide (H2 O2 ) using three different treatment types (pre-, simultaneous, and post-treatment). The isolated lymphocytes were incubated with different concentrations of amygdalin (0.86-13.75 µg/ml) alone and in combination with H2 O2 (100 µM). The results indicated that amygdalin exhibited an antigenotoxic effect against H2 O2 , but it did not induce the genotoxic effect alone in tested concentrations in vitro on human lymphocytes. PRACTICAL APPLICATIONS: Amygdalin is a natural compound used in alternative medicine as an anti-cancer, antipyretic, and cough suppressant. The comet assay which is relatively simple, rapid, sensitive, and economically efficient, measures the changes in genomic stability. Assessment of amygdalin alone has no genotoxic effect on human lymphocytes. Moreover, antigenotoxicity applications (pre-, simultaneous, and post-treatments) of amygdalin significantly reduced the DNA damage induced by H2 O2 on isolated human lymphocytes. In conclusion, amygdalin is not genotoxic, also, it exhibited antigenotoxic activity against oxidatively damaged DNA due to its antioxidant properties on human lymphocytes.

Magnetically Directed Enzyme/Prodrug Prostate Cancer Therapy Based on β-Glucosidase/Amygdalin

Background

β-Glucosidase (β-Glu) can activate amygdalin to kill prostate cancer cells, but the poor specificity of this killing effect may cause severe general toxicity in vivo, limiting the practical clinical application of this approach.

Materials and Methods

In this study, starch-coated magnetic nanoparticles (MNPs) were successively conjugated with β-Glu and polyethylene glycol (PEG) by chemical coupling methods. Cell experiments were used to confirm the effects of immobilized β-Glu on amygdalin-mediated prostate cancer cell death in vitro. Subcutaneous xenograft models were used to carry out the targeting experiment and magnetically directed enzyme/prodrug therapy (MDEPT) experiment in vivo.

Results

Immobilized β-Glu activated amygdalin-mediated prostate cancer cell death. Tumor-targeting studies showed that PEG modification increased the accumulation of β-Glu-loaded nanoparticles in targeted tumor tissue subjected to an external magnetic field and decreased the accumulation of the nanoparticles in the liver and spleen. Based on an enzyme activity of up to 134.89 ± 14.18mU/g tissue in the targeted tumor tissue, PEG-β-Glu-MNP/amygdalin combination therapy achieved targeted activation of amygdalin and tumor growth inhibition in C57BL/6 mice bearing RM1 xenografts. Safety evaluations showed that this strategy had some impact on liver and heart function but did not cause obvious organ damage.

Conclusion

All findings indicate that this magnetically directed enzyme/prodrug therapy strategy has the potential to become a promising new approach for targeted therapy of prostate cancer.

Evaluation of the effective dose of amygdalin for the improvement of antioxidant gene expression and suppression of oxidative damage in mice

BACKGROUND

Little is known regarding the toxic and therapeutic doses of amygdalin. Treatment regimens and schedules can vary between humans and animal models, and there have been reports of cyanide toxicity due to amygdalin use.

OBJECTIVE

The aim of this study was to evaluate the effect of different doses of amygdalin on antioxidant gene expression and suppression of oxidative damage in mice.

METHODS

Forty adult male mice were divided randomly into four groups (n = 10) as follows and treated orally for two weeks: a control group treated with saline solution, a group treated with amygdalin at 200 mg/kg body weight, a group treated with amygdalin at 100 mg/kg body weight, and a group treated with amygdalin at 50 mg/kg body weight. Liver and testis samples were collected for gene expression, biochemical and histopathological analyses.

RESULTS

The mice treated with medium-dose amygdalin (100 mg/kg) showed upregulated mRNA expression of glutathione peroxidase (P < 0.01) and superoxide dismutase (P < 0.05) and significantly decreased lipid peroxidation (P < 0.05) in hepatic and testicular tissues compared to those in the untreated groups (controls), with mild histopathological effects. The mice treated with high-dose of amygdalin (200 mg/kg) showed downregulated mRNA expression of glutathione peroxidase and superoxide dismutase (P < 0.01) and significantly increased lipid peroxidation (P < 0.05) in both hepatic and testicular tissues compared to those in the untreated groups (controls), with an apparent effect at the histopathological level. No effects were observed in the mice treated with low-dose amygdalin (50 mg/kg) at the gene, protein and histopathological level.

CONCLUSION

Low-and medium-dose amygdalin did not induce toxicity in the hepatic and testicular tissues of male mice, unlike high-dose amygdalin, which had a negative effect on oxidative balance in mice. Therefore, amygdalin at a moderate dose may improve oxidative balance in mice.

Rebound metabolic acidosis following intentional amygdalin supplement overdose

Introduction: Amygdalin, marketed misleadingly as supplement "Vitamin B17," is a cyanogenic glycoside. When swallowed, it is hydrolyzed into cyanide in the small intestine, which causes histotoxic hypoxia via inhibition of cytochrome c oxidase. It remains available for purchase online despite a ban from the US Food and Drug Administration. We report a case of massive intentional amygdalin overdose resulting in recurrent cyanide toxicity after initial successful antidotal therapy.Case summary: A 33-year-old woman intentionally ingested 20 g of "apricot POWER B17 Amygdalin" supplements. She presented five hours post-ingestion with vital signs: P 127 bpm, BP 112/65 mmHg, RR 25/min, temperature 98.1 °F, and SpO2 98% RA. She was in agitated delirium, diaphoretic, and mydriatic. Her VBG was notable for a pH of 7.27 (rr 7.32-7.42) and lactate 14.1 mmol/L (rr 0.5-2.2), with ECG demonstrating QTc 538 ms (normal <440 ms). She was empirically treated with hydroxocobalamin and supportive care, but worsened clinically, requiring intubation and additional hydroxocobalamin and sodium thiosulfate, which resolved her toxicity. Twelve hours later, she developed recurrent hypotension, acidemia, and QTc prolongation that resolved with repeat hydroxocobalamin and sodium thiosulfate dosing.Discussion: Our case demonstrates rebound metabolic acidosis after massive amygdalin overdose. Toxicity was associated with prolonged QTc, which warrants further investigation into clinical significance. Redosing of combination antidotal therapy suggested efficacy without adverse effects.

Recent updates and future perspectives about amygdalin as a potential anticancer agent: A review

The overall incidence of cancer is increasing in recent years. Despite advances in various comprehensive treatments, the mortality of advanced malignant tumors remains at a high level. Numerous pharmacological studies have confirmed that many Chinese herbal medicines possess remarkable antitumor activities. Amygdalin, mainly existing in bitter almond, is reported to have antitumor properties in addition to the antioxidative, antibacterial, anti‐inflammatory and immunoregulatory activities. This article summarizes the structural characteristics of amygdalin, its antitumor mechanisms, and recent progress and achievement in the research of amygdalin, hoping that it could provide theoretical clues for exploring the clinical value of amygdalin against tumors. Amygdalin is known to have an antitumor effect in solid tumors such as lung cancer, bladder cancer and renal cell carcinoma by affecting cell cycle, inducing apoptosis and cytotoxicity, and regulating immune function. Further research is needed to elucidate the pharmacological mechanisms of amygdalin in terms of the optimal dosage, the feasibility of combined use of amygdalin with other antitumor drugs, and even artificial synthesis of the active components in amygdalin, for the sake of enhancing its antitumor activities and reducing its adverse effects for clinical use.

Effects of toxic β-glucosides on carbohydrate metabolism in cotton bollworm, Helicoverpa armigera (Hübner)

The purpose of this study was to evaluate the effects of three toxic β-glucosides, phlorizin, santonin, and amygdalin, on carbohydrate metabolism in the cotton bollworm, Helicoverpa armigera (Hübner), when diets mixed with β-glucosides were fed to third-instar larvae. The growth of the larvae was significantly inhibited by exposure to santonin after 96 hr but not obviously affected by phlorizin and amygdalin. The midgut trehalase activities were only 51.7%, 32%, and 42.5% of that of the control after treatment with phlorizin, santonin and amygdalin at 2 mg/ml, respectively. In the hemolymph and fat body, the amount of trehalose decreased in all cases. However, the effects of santonin on the alteration of the glycogen and glucose levels as well as the activities of glycogen phosphorylase, were different than those of the other two β-glucosides. It appears that the three β-glucosides have different influences on the carbohydrate metabolism of cotton bollworm.

The anti-cancer effect of amygdalin on human cancer cell lines

Derived from rosaceous plant seed, amygdalin belongs to aromatic cyanogenic glycoside group, and its anticancer effects have been supported by mounting evidence. In this study, we objected to investigate amygdalin effect on two antiapoptotic genes (Survivin, XIAP) and two lncRNAs (GAS5, MALAT1) in human cancer cells (A549, MCF7, AGS). Employing RT-qPCR analysis, we compared the mRNA levels of the genes related to apoptosis in A549, MCF7, and AGS cancer cells between amygdalin-treated (24, 48 and 72 h) and un-treated groups. RNA was extracted from both cell groups and then cDNAs were synthesized. The changes in the gene expression levels were specified using ΔΔCt method. RT-qPCR analysis has revealed that the expression of Survivin, XIAP, GAS5 and MALAT1 in amygdala-treated cancer cells were significantly different, compared to the un-treated cells. However, these expressions were different depending on the treatment time. According to the results, amygdalin significantly inhibited the expression level of Survivin, and XIAP genes in treated via untreated group. Our findings suggest that amygdalin might have an anticancer effect due to the various gene expressions in A549, MCF7, and AGS human cancer cells, showing it's potential as a natural therapeutic anticancer drug.