-
Anti-cancer Agents in Medicinal... 2018Amygdalin is a cyanogenic glycoside which is described as a naturally occurring anticancer agent. Current review highlights apoptosis-inducing attributes of amygdalin... (Review)
Review
BACKGROUND
Amygdalin is a cyanogenic glycoside which is described as a naturally occurring anticancer agent. Current review highlights apoptosis-inducing attributes of amygdalin towards different cancers and its potential application as an anti-cancer agent in cancer therapy.
METHOD
Data about amygdalin was retrieved from all major scientific databases i.e., PubMed, ScienceDirect, Google Scholar, Scopus and Medline by using combination of keywords like amygdalin, apoptosis, laetrile, vitamin B- 17, pro-apoptotic proteins, anti-apoptotic proteins, hydrogen cyanide, mechanism of action of amygdalin and amygdalin therapy on humans. However, no specific time frame was followed for collection of data.
RESULTS
Data collected from already published articles revealed that apoptosis is a central process activated by amygdalin in cancer cells. It is suggested to stimulate apoptotic process by upregulating expression of Bax (proapoptotic protein) and caspase-3 and downregulating expression of Bcl-2 (anti-apoptotic protein). It also promotes arrest of cell cycle in G0/G1 phase and decrease number of cells entering S and G2/M phases. Thus, it is proposed to enhance deceleration of cell cycle by blocking cell proliferation and growth.
CONCLUSION
The current review epitomizes published information and provides complete interpretations about all known anti-cancer mechanisms of amygdalin, possible role of naturally occurring amygdalin in fight against cancer and mistaken belief about cyanide toxicity causing potential of amygdalin. However, well-planned clinical trials are still needed to be conducted to prove effectiveness of this substance in vivo and to get approval for human use.
Topics: Amygdalin; Antineoplastic Agents, Phytogenic; Apoptosis; Cell Cycle Checkpoints; Cell Proliferation; Drug Screening Assays, Antitumor; Humans; Molecular Structure; Neoplasms; Prunus armeniaca
PubMed: 29308747
DOI: 10.2174/1871520618666180105161136 -
Phytomedicine : International Journal... Apr 2016The cyanogenic diglucoside, amygdalin, has gained high popularity among cancer patients together with, or in place of, conventional therapy. Still, evidence based... (Review)
Review
BACKGROUND
The cyanogenic diglucoside, amygdalin, has gained high popularity among cancer patients together with, or in place of, conventional therapy. Still, evidence based research on amygdalin is sparse and its benefit controversial.
PURPOSE
Since so many cancer patients consume amygdalin, and many clinicians administer it without clear knowledge of its mode of action, current knowledge has been summarized and the pros and cons of its use weighed.
METHODS
A retrospective analysis was conducted for amygdalin relevant reports using the PubMed database with the main search term "Amygdalin" or "laetrile", at times combined with "cancer", "patient", "cyanide" or "toxic". We did not exclude any "unwanted" articles. Additionally, internet sources authorized by governmental or national institutions have also been included.
SECTIONS
Individual chapters summarize pharmacokinetics, preclinical and clinical studies and toxicity.
CONCLUSION
No convincing evidence showing that amygdalin induces rapid, distinct tumor regression in cancer patients, particularly in those with late-stage disease, is apparent. However, there is also no evidence that purified amygdalin, administered in "therapeutic" dosage, causes toxicity. Multiple aspects of amygdalin administration have not yet been adequately explored, making further investigation necessary to evaluate its actual therapeutic potential.
Topics: Amygdalin; Antineoplastic Agents, Phytogenic; Cyanides; Humans; Neoplasms; Phytotherapy; Plant Extracts; Quackery; Rosaceae
PubMed: 27002407
DOI: 10.1016/j.phymed.2016.02.004 -
Klinicka Onkologie : Casopis Ceske a... 2019Amygdalin is a natural compound primarily found in seeds of fruit trees. In the human body, it is hydrolyzed to benzaldehyde, glucose, and cyanide, which is considered... (Review)
Review
BACKGROUND
Amygdalin is a natural compound primarily found in seeds of fruit trees. In the human body, it is hydrolyzed to benzaldehyde, glucose, and cyanide, which is considered the active component of amygdalin. The semi-synthetic form of amygdalin is known under the commercial name Laetrile® or as vitamin B17.
PURPOSE
This review aims to provide a comprehensive overview of studies that evaluated the potential therapeutic effects of amygdalin in oncology. Preclinical studies provided information about the mechanisms of action of amygdalin in vitro and in vivo and its toxicity. Recent in vitro studies demonstrated the effects of amygdalin on the cell cycle, apoptosis, and synthesis of cyclooxygenase-2, inducible nitric oxide synthase, E-cadherin, and integrins β1 and β4. However, amygdalin exhibited no or low treatment efficiency in preclinical in vivo studies. Conversely, many case studies describe the anti-tumor effects of amygdalin, but these have not been confirmed in clinical trials. Only two clinical studies published almost 40 years ago focused on the safety of amygdalin administered orally and intravenously. Although these studies reported that amygdalin had no benefit in 178 cancer patients, this compound has recently come to the attention of both scientists and patients. The results of recent in vitro studies are promising and indicate that amygdalin has a oncopreventive effect, although this must be confirmed by in vivo studies and clinical trials. Considering its proven toxicity and unconvincing clinical effects, amygdalin cannot currently be recommended to oncology patients as a supportive treatment.
Topics: Amygdalin; Animals; Antineoplastic Agents, Phytogenic; Humans; Neoplasms
PubMed: 31610669
DOI: 10.14735/amko2019360 -
Molecules (Basel, Switzerland) Apr 2021Amygdalin (d-Mandelonitrile 6--β-d-glucosido-β-d-glucoside) is a natural cyanogenic glycoside occurring in the seeds of some edible plants, such as bitter almonds and... (Review)
Review
Amygdalin (d-Mandelonitrile 6--β-d-glucosido-β-d-glucoside) is a natural cyanogenic glycoside occurring in the seeds of some edible plants, such as bitter almonds and peaches. It is a medically interesting but controversial compound as it has anticancer activity on one hand and can be toxic via enzymatic degradation and production of hydrogen cyanide on the other hand. Despite numerous contributions on cancer cell lines, the clinical evidence for the anticancer activity of amygdalin is not fully confirmed. Moreover, high dose exposures to amygdalin can produce cyanide toxicity. The aim of this review is to present the current state of knowledge on the sources, toxicity and anticancer properties of amygdalin, and analytical methods for its determination in plant seeds.
Topics: Amygdalin; Animals; Glycosides; Humans; Hydrogen Cyanide; Seeds
PubMed: 33924691
DOI: 10.3390/molecules26082253 -
Biomolecules Oct 2022Bioactive amygdalin, found in high concentrations in bitter almonds, has been recognized as a symbol of the cyanogenic glycoside chemical organic substance, which was... (Review)
Review
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.
Topics: Humans; Amygdalin; Antioxidants; Gastrointestinal Microbiome; Hydrogen Cyanide; Chitosan; Neoplasms; Pharmaceutical Preparations; Alginates
PubMed: 36291723
DOI: 10.3390/biom12101514 -
Journal of Primary Health Care Dec 2018
Review
Topics: Amygdalin; Animals; Antineoplastic Agents; Humans
PubMed: 31039967
DOI: 10.1071/HC15939 -
Polski Merkuriusz Lekarski : Organ... May 2015In this publication we described amygdalin. It was isolated for the first time in the 19th century. Amygdalin is called interchangeably vitamin B17 or laetrile. Since... (Review)
Review
In this publication we described amygdalin. It was isolated for the first time in the 19th century. Amygdalin is called interchangeably vitamin B17 or laetrile. Since more than a hundred years, there has been reports about its unique anticancer properties. We tried to introduce the present knowledge about therapeutic efficacy of laetrile. Most of these studies has been made in the in vitro environment. The lack of appropriate studies forced scientists to examine the positive influence of amygdalin on many diseases like: bladder cancer, prostate cancer, cervical cancer, colon cancer, promyelocytic leukemia, chronic kidney disease, psoriasis and other.
Topics: Amygdalin; Antineoplastic Agents, Phytogenic; Humans; Kidney Failure, Chronic; Molecular Structure; Neoplasms; Psoriasis
PubMed: 26039028
DOI: No ID Found -
Immunopharmacology and Immunotoxicology Jun 2018Amygdalin, named as 'laetrile' and 'vitamin B-17' was initially supposed to be a safe drug for cancer treatment and was recognized by followers of natural medicine since... (Review)
Review
Amygdalin, named as 'laetrile' and 'vitamin B-17' was initially supposed to be a safe drug for cancer treatment and was recognized by followers of natural medicine since it has been considered to be hydrolyzed only in cancer cells releasing toxic hydrogen cyanide (HCN), and thus destroying them. Unfortunately, current studies have shown that HCN is also released in normal cells, therefore it may not be safe for human organism. However, there have still been research works conducted on anti-cancer properties of this compound. In vitro experiments have shown induction of apoptosis by amygdalin as a result of increased expression of Bax protein and caspase-3 and reduced expression of antiapoptotic BcL-2protein. Amygdalin has also been shown to inhibit the adhesion of breast cancer cells, lung cancer cells and bladder cancer cells by decreased expression of integrin's, reduction of catenin levels and inhibition of the Akt-mTOR pathway, which may consequently lead to inhibition of metastases of cancer cells. It has also been revealed that amygdalin in renal cancer cells increased expression of p19 protein resulting in inhibition of cell transfer from G1-phase to S-phase, and thus inhibited cell proliferation. Other studies have indicated that amygdalin inhibits NF-kβ and NLRP3 signaling pathways, and consequently has anti-inflammatory effect due to reducing the expression of proinflammatory cytokines such as pro-IL-1β. Moreover, the effect of amygdalin on TGFβ/CTGF pathway, anti-fibrous activity and expression of follistatin resulting in activation of muscle cells growth has been reported. This compound might be applicable in the treatment of various cancer cell types.
Topics: Amygdalin; Animals; G1 Phase; Gene Expression Regulation, Neoplastic; Humans; Neoplasm Proteins; Neoplasms; S Phase; Signal Transduction
PubMed: 29486614
DOI: 10.1080/08923973.2018.1441301 -
Future Medicinal Chemistry May 2013Psoriasis is one of the most prevalent immune-mediated illness worldwide. The disease can still only be managed rather than cured, so treatments are aimed at clearing... (Review)
Review
Psoriasis is one of the most prevalent immune-mediated illness worldwide. The disease can still only be managed rather than cured, so treatments are aimed at clearing skin lesions and preventing their recurrence. Several treatments are available depending on the extent of the psoriatic lesion. Among the topical treatments corticostereoids, vitamin D3 analogs and retinoids are commonly used. However, these treatments may have adverse effects in the long term. Conversely, systemic conventional treatments include immunosuppresors such as cyclosporin or methotrexate associated with high toxicity levels. Biologicals are alternative therapeutical agents introduced in the last 10 years. These include fusion proteins or monoclonal antibodies designed to inhibit the action of specific cytokines or to prevent T-lymphocyte activation. However, due to recent knowledge on the etiology of the disease, diverse new small molecules have appeared as promising alternatives for the treatment of psoriasis. Among them, inhibitors of JAK3, inhibitors of PDE 4 and amygdalin analogs. The latter are promising small molecules presently in preclinical studies which are the object of the present report.
Topics: Amygdalin; Animals; Antibodies, Monoclonal; Antineoplastic Agents, Phytogenic; Humans; Phosphodiesterase 4 Inhibitors; Protein Kinase Inhibitors; Psoriasis; Structure-Activity Relationship; T-Lymphocytes
PubMed: 23651093
DOI: 10.4155/fmc.13.27 -
Cancer Medicine Jun 2019The overall incidence of cancer is increasing in recent years. Despite advances in various comprehensive treatments, the mortality of advanced malignant tumors remains... (Review)
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.
Topics: Amygdalin; Antineoplastic Agents; Humans; Neoplasms
PubMed: 31066207
DOI: 10.1002/cam4.2197