Amygdalin (Vitamin B17) pretreatment attenuates experimentally induced acute autoimmune hepatitis through reduction of CD4+ cell infiltration

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.

Effects of amygdalin on ferroptosis and oxidative stress in diabetic retinopathy progression via the NRF2/ARE signaling pathway

Oxidative stress has been involved in the pathogenesis of diabetic retinopathy (DR). Amygdalin is an effective component of bitter almond that exhibits excellent antioxidant properties. We explored the effects of amygdalin on ferroptosis and oxidative stress in high-glucose (HG)-stimulated human retinal endothelial cells (HRECs) via the NRF2/ARE pathway. HG-stimulated HRECs were used to establish a DR model. Cell viability was evaluated using the MTT assay. The release of lactate dehydrogenase was used to evaluate cell toxicity. The protein levels of NRF2, NQO1, and HO-1 were detected using western blotting. The GSH, GSSG, GPX4, SOD, CAT, MDA, and Fe2+ levels in the HRECs were also detected. Flow cytometry was used to detect reactive oxygen species (ROS) using a fluorescent probe. Immunofluorescence staining was performed to detect NRF2 expression. The results revealed that HG stimulation decreased the levels of GSH, GPX4, SOD, and CAT but increased those of MDA, ROS, GSSG, and Fe2+ in HRECs. Ferrostatin-1 treatment reversed the effects of HG stimulation, whereas erastin aggravated these effects. Amygdalin treatment relieved HG-induced injury in HRECs. Amygdalin treatment promoted the nuclear transport of NRF2 in HG-stimulated HRECs. NQO1 and HO-1 levels were upregulated in HG-stimulated HRECs after amygdalin treatment. An inhibitor of NRF2 reversed the effects of amygdalin. Therefore, amygdalin treatment inhibited ferroptosis and oxidative stress in HG-stimulated HRECs by activating the NRF2/ARE signaling pathway.

Involvement of the SIRT1-NLRP3 pathway in the inflammatory response

The silent information regulator 2 homolog 1-NACHT, LRR and PYD domains-containing protein 3 (SIRT1-NLRP3) pathway has a crucial role in regulation of the inflammatory response, and is closely related to the occurrence and development of several inflammation-related diseases. NLRP3 is activated to produce the NLRP3 inflammasome, which leads to activation of caspase-1 and cleavage of pro-interleukin (IL)-1β and pro-IL-18 to their active forms: IL-1β and IL-18, respectively. They are proinflammatory cytokines which then cause an inflammatory response.SIRT1 can inhibit this inflammatory response through nuclear factor erythroid 2-related factor 2 and nuclear factor-kappa B pathways. This review article focuses mainly on how the SIRT1-NLRP3 pathway influences the inflammatory response and its relationship with melatonin, traumatic brain injury, neuroinflammation, depression, atherosclerosis, and liver damage. Video Abstract.

Impact of intestinal microbiota on metabolic toxicity and potential detoxification of amygdalin

Amygdalin (Amy) is metabolized into cyanide in vivo, which may lead to fatal poisoning after oral administration. The defense mechanisms against toxic cyanide have not yet been adequately studied. In this study, comparative toxicokinetics study of Amy was performed in normal and pseudo germ-free rats. The efficiency of cyanide release was significant higher in normal group when given a single oral dose of 440 mg/kg (50% median lethal dose). Thiocyanate, the detoxification metabolite, was firstly detected in feces, caecum, and intestinal microbiota incubation enzymic system. The results suggest intestinal microbiota is involved in bidirectional regulation of toxicity and detoxification of Amy. We further identified the species related to cyanogenesis of Amy with metagenomic sequencing, such as Bifidobacterium pseudolongum, Marvinbryantia formatexigens, and Bacteroides fragilis. Functional analysis of microbiota reveals the detoxification potential of intestinal microbiota for cyanide. Sulfurtransferase superfamily, such as rhodanese, considered as main detoxification enzymes for cyanide, are largely found in Coriobacteriaceae bacterium, Butyricicoccus porcorum, Akkermansia muciniphila, etc. Besides, cyanoamino acid metabolism pathway dominated by Escherichia coli may contribute to the detoxification metabolism of cyanide. In summary, intestinal microbiota may be the first line of defense against the toxicity induced by Amy.

Cucurbitacin E glucoside alleviates concanavalin A-induced hepatitis through enhancing SIRT1/Nrf2/HO-1 and inhibiting NF-ĸB/NLRP3 signaling pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Cucurbitacins are highly oxygenated tetracyclic triterpenoids, that represent the major metabolites reported from C. colocynthis (L.) Schrad.. Cucurbitacin E glucoside (CuE) is a tetracyclic triterpene glycoside separated from Cucurbitaceae plants. CuE has potent anti-inflammatory, immunomodulatory, and anti-tumor properties.

AIM OF THE STUDY

The current study aimed at examining the hepatoprotective effect of CuE against concanavalin A (Con A)-produced hepatitis.

MATERIALS AND METHODS

Mice were intravenously administered Con A (15 mg/kg) to induce AIH. CuE was orally administered at two different doses for five days preceding Con A injection.

RESULTS

The results revealed that CuE pretreatment markedly attenuated the serum indices of hepatotoxicity and the severity of hepatic lesions. CuE depressed Con A-provoked increment in CD4⁺ T-cells in hepatic tissue. The antioxidant activity of CuE was evident through its ability to decrease markers of Con A-induced oxidative stress (malondialdehyde, 4-hydroxyenonanal, and protein carbonyl) and intensified the antioxidants in the hepatic tissue (SOD, GSH, and TAC). CuE increased mRNA expression of SIRT1 and Nrf2 as well as its binding capacity. Subsequently, CuE augmented mRNA expression of Nrf2 targeted genes as NQO1, GCL, and HO-1 and recovered its normal level. CuE inhibited the activation of NF-κB/downstream pro-inflammatory mediators signaling. Furthermore, CuE attenuated the mRNA expression of NLRP3 and its associated genes.

CONCLUSION

Collectively, these results demonstrated the remarkable hepatoprotective potential of CuE towards Con A-induced AIH which was mediated via suppression of oxidative stress, enhancing SIRT1/Nrf2/HO-1, and prohibition of the NF-κB/NLRP3 signaling. CuE could be a candidate for hepatitis patients.

Changes in immune profile affect disease progression in hepatocellular carcinoma

Objective: Hepatocellular carcinoma (HCC) as a chronic liver condition is largely associated with immune responses. Previous studies have revealed that different subsets of lymphocytes play fundamental roles in controlling or improving the development and outcome of solid tumors like HCC. Hence, this study aimed to investigate whether immune system changes were related to disease development in HCC patients. Methods: Peripheral blood mononuclear cells were isolated from 30 HCC patients and 30 healthy volunteers using Ficoll density centrifugation. The isolated cells were stained with different primary antibodies and percentages of different immune cells were determined by flow cytometry. Results: HCC patients indicated significant reductions in the numbers of CD4⁺ cells, Tbet+IFNγ+cells, and GATA+IL-4+cells in peripheral blood in comparison with healthy individuals (p < 0.05). There was no significant change in IL-17+RORγt+cells between patient and healthy groups. In contrast, Foxp3+CD127^lowcell frequency was significantly higher in patients than healthy subjects (p < 0.0001). The numbers of Th1, Th2, and Th17 cells were significantly lower in HCC patients than healthy control (p < 0.0001), although the reduction in Th2 cell numbers was not statistically significant. On the contrary, Treg percentage showed a significant increase in patients compared to healthy subjects (p < 0.0001). Other data revealed that Th1, Th2, and Th17 cell frequencies were significantly higher in healthy individuals than patients with different TNM stages of HCC, with the exception of Th2 in patients with stage II HCC (p < 0.01-0.05). Treg percentage was significantly increased in patients with different TNM stages (p < 0.0001). Among all CD4⁺ T cells, the frequency of Th2 cell was significantly associated with TNM stages of HCC (p < 0.05). Conclusion: Our data provide further evidence to show that immune changes may participate in determining HCC progression and disease outcome. However, it should be mentioned that more investigations are needed to clarify our results and explain possible impacts of other immune cells on the pathogenesis of HCC.

Punica granatum and amygdalin extracts plus cobalamin combined with albendazole reduce larval burden and myositis in experimental trichinosis

Trichinellosis is a zoonosis results from eating raw or semi-cooked meat of infected animals. Medicinal plants have been used lately as alternatives and/or combined therapies to resolve some drawbacks of the current regimens. This work analyzed the effect of albendazole monotherapy on Trichinella spiralis experimental infection (group A), in comparison to P. granatum and amygdalin extracts +cobalamin (group B), plus its combination with albendazole (group C). The study revealed that the extracts alone or combined with albendazole had an inferior effect to albendazole monotherapy regarding number of adult worms (40.83 ±3.82, 18.67 ±1.86 and 16.83 ±2.32, respectively). However, their effect was more obvious in muscle phase combined with albendazole, achieving the lower number of larvae/mL tissue homogenate (22.33 ±3.27 in comparison to 39.67 ±2.58 achieved by albendazole monotherapy). The extracts exerted a significant immunomodulatory effect by reducing the local CD4+ expression in the intestine as well as in muscle phase (1.15 ±0.25 and 3.80 ±0.65 in comparison to 4.97 ±0.37 and 12.20 ±0.87 with albendazole monotherapy, respectively). So, these extracts improved the therapeutic efficacy of albendazole, specifically in muscle phase and counteracted the inflammatory reaction caused by albendazole monotherapy, thus extensively alleviating the resulting myositis.

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.

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 (H2O2) 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 H2O2 (100 µM). The results indicated that amygdalin exhibited an antigenotoxic effect against H2O2, 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 H2O2 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.

Hepatic ameliorative role of vitamin B17 against Ehrlich ascites carcinoma-induced liver toxicity

Vitamin B17 (VB17), also known as amygdalin and laetrile, is a type of carbohydrate occurring naturally in many plants, such as apricot kernels which have obtained a great interest in cancer therapy. This study aimed to investigate the hepatic protective potential of VB17 against Ehrlich ascites carcinoma (EAC)-bearing mice-induced liver injury, DNA damage, apoptotic P53, and PCNA alterations. A total of 100 female mice were divided into 5 groups (1st group, control group; 2nd group, VB17 group; 3rd group, EAC group; 4th group, pre-treated EAC with VB17; 5th group, co-treated EAC with VB17). Results showed that the presence of VB17 in pre-treated and co-treated groups lead to decreased DNA damage, microsomal protein, NADPH cytochrome c reductase, alpha-fetoprotein (AFP), AST, ALT, and ALP while showed increased cytochrome b5, cytochrome P450 amidopyrine N-demethylase, and aniline 4-hydroxylase compared with the EAC group. Many histopathological changes were observed in liver sections in EAC as moderate fibrosis and marked diffuse necrosis of hepatic tissue, marked inflammatory cells, and congested blood sinusoids. On the other hand, there was a moderate degree of improvement in hepatocytes in liver sections in pre-treated VB17+EAC, while a mild degree of improvement in hepatocytes, moderate cellular infiltrations, and moderate cytoplasmic vacuolization of hepatocytes in liver sections in co-treated EAC+VB17. In addition, there was a depletion in hepatic P53 and PCNA protein expression compared with the EAC group. It could be concluded that VB17 has a potential hepatoprotective effect against EAC cell-induced liver toxicity.