Indicaxanthin from Opuntia ficus-indica Fruit Ameliorates Glucose Dysmetabolism and Counteracts Insulin Resistance in High-Fat-Diet-Fed Mice

A bio-guided search of anti-steatotic compounds in Opuntia stricta var. dillenii by fast centrifugal partition chromatography

The fruit extract of Opuntia stricta var. dillenii (OSDE) has been recognized for its effects on hepatic steatosis, but the compounds responsible for this activity have yet to be precisely identified. This work aimed to evaluate the anti-steatotic effect of OSDE and its different fractions obtained by fast centrifugal-partition chromatography (FCPC) to identify the compounds potentially responsible for this biological activity. Hepatic lipid accumulation and triglyceride content were evaluated, as well as cellular antioxidant activity and inhibition of lipid peroxidation. Pool 1-Pool 4 showed lower lipid accumulation than OSDE in liver cells, while a greater reduction in triglyceride levels, even lower than OSDE and lovastatin (LOV), was observed for Pool 1, 9, and 10. Compared to OSDE, Pools 1,6, 7, and 12 showed higher cellular antioxidant effects, whereas OSDE showed better lipid peroxidation inhibition than all of Pools. Quinic and piscidic acids were the main bioactive present in Pool 1, exhibiting +1597 % and + 997 % increases in their content related to OSDE, respectively. Likewise, the most abundant compounds in Pool 2- Pool 4 were betalains such as betanin and isobetanin, with +163 % and + 162 % of increases in their concentration related to OSDE, respectively. Antioxidant effects in Pools 6 and 7 correlated with higher phenolic acid concentration. OSDE significantly reduced triglyceride levels in a steatotic-induced model. Although OSDE showed anti-steatotic effects, they were more pronounced for some of its constituents in FCPC Pools. Results suggested that these compounds might be potentially responsible for this anti-steatotic effect. FCPC fractionation facilitated the separate biological evaluation of OSDE constituents and thus identified them. Future studies should focus on validating these anti-steatotic effects in in vivo models.

Selected Mesoamerican Crops - Anti-Obesity Potential and Health Promotion. A Review

Mesoamerica is the center of origin of a great number of food crops that nowadays are part of a healthy diet. Pre-Columbian civilizations utilized more than 90% of these foods as ingredient or in main dishes, as well as for remedies and religious ceremonies. Since several years ago, Mesoamerican foods have been recognized by their outstanding concentration of bioactive compounds, including, phenolic compounds, pigments, essential fatty acids, amino acids, peptides, carbohydrates and vitamins, which provide a great number of health benefits. As a result of their unique composition, these ancient crops have several positive effects, such as hypoglycemic, antioxidant, anti-obesity, anti-inflammatory, anti-ageing, neuroprotective, anti-diarrheal, and anti-hypercholesterolemic capacity. Hence, this review is focused mainly in the anti-obesity and antioxidant potential of some of the most cultivated, harvested, as well as commercialized and consumed, food crops native of Mesoamerica, like, nopal and its fruit (Opuntia ficus indica spp.), chia (Salvia hispanica L.), pumpkin (Cucurbita spp.) and cacao (Theobroma cacao).

Cytotoxic activity, selectivity, and clonogenicity of fruits and resins of Saudi medicinal plants against human liver adenocarcinoma

Background

Edible fruits and resins provide various benefits to mankind including potential medicinal applications. This study aimed to determine the cytotoxicity, selectivity, and clonogenicity of fruits and exudates of certain Saudi medicinal plants (Anethum graveolens (BEP-09), Opuntia ficus-indica (L.) Miller (BEP-10), Boswellia serrata Roxb. ex Colebr. (BEP-11), and Commiphora myrrha (BEP-12)) against human liver adenocarcinoma (HepG2).

Methods

Initial cytotoxicity and cell line selectivity against different cell lines were screened using MTT assay. The most promising extract was subjected to gas chromatography-mass spectrometry (GC-MS) analysis to determine the main phytoconstituents. Clonogenicity was checked for the most active extract.

Results

The selected plants' fruits and resins possess a significant cytotoxic activity estimated as IC50. The fruit of BEP-10 was found to be the most active extract against liver cancer cells (IC50 = 2.82) comparable to both doxorubicin (IC50 = 1.40) and camptothecin (IC50 = 1.11). It showed a selectivity index of 4.47 compared to the normal human foetal lung fibroblast (MRC5) cells. BEP-10 showed a dose-dependent clonogenic effect against HepG2 cells comparable to the effect of doxorubicin. The GC-MS chromatogram of BEP-10 extract revealed the presence of eight small polar molecules, representing 73% of the total identified compounds and the rest three molecules (27%) were non-polar constituents. The furan derivatives represent the chief components in BEP-10 (16.3%), while the aldehyde 5-(hydroxymethyl)-2-furancarboxaldehyde was found to be the main molecule (13.2%).

Conclusion

The fruits of BEP-10 have a potential cytotoxic effect particularly against HepG2. The identified phytoconstituents in the tested plant extract might contribute to the investigated cytotoxic activity.

Positive Impacts of Aphanizomenon Flos Aquae Extract on Obesity-Related Dysmetabolism in Mice with Diet-Induced Obesity

The present study evaluated the ability of KlamExtra®, an Aphanizomenon flos aquae (AFA) extract, to counteract metabolic dysfunctions due to a high fat diet (HFD) or to accelerate their reversion induced by switching an HFD to a normocaloric diet in mice with diet-induced obesity. A group of HFD mice was fed with an HFD supplemented with AFA (HFD-AFA) and another one was fed with regular chow (standard diet-STD) alone or supplemented with AFA (STD-AFA). AFA was able to significantly reduce body weight, hypertriglyceridemia, liver fat accumulation and adipocyte size in HFD mice. AFA also reduced hyperglycaemia, insulinaemia, HOMA-IR and ameliorated the glucose tolerance and the insulin response of obese mice. Furthermore, in obese mice AFA normalised the gene and the protein expression of factors involved in lipid metabolism (FAS, PPAR-γ, SREBP-1c and FAT-P mRNA), inflammation (TNF-α and IL-6 mRNA, NFkB and IL-10 proteins) and oxidative stress (ROS levels and SOD activity). Interestingly, AFA accelerated the STD-induced reversion of glucose dysmetabolism, hepatic and VAT inflammation and oxidative stress. In conclusion, AFA supplementation prevents HFD-induced dysmetabolism and accelerates the STD-dependent recovery of glucose dysmetabolism by positively modulating oxidative stress, inflammation and the expression of the genes linked to lipid metabolism.

"Golden" Tomato Consumption Ameliorates Metabolic Syndrome: A Focus on the Redox Balance in the High-Fat-Diet-Fed Rat

Tomato fruits defined as "golden" refer to a food product harvested at an incomplete ripening stage with respect to red tomatoes at full maturation. The aim of this study is to explore the putative influence of "golden tomato" (GT) on Metabolic Syndrome (MetS), especially focusing on the effects on redox homeostasis. Firstly, the differential chemical properties of the GT food matrix were characterized in terms of phytonutrient composition and antioxidant capacities with respect to red tomato (RT). Later, we assessed the biochemical, nutraceutical and eventually disease-modifying potential of GT in vivo in the high-fat-diet rat model of MetS. Our data revealed that GT oral supplementation is able to counterbalance MetS-induced biometric and metabolic modifications. Noteworthy is that this nutritional supplementation proved to reduce plasma oxidant status and improve the endogenous antioxidant barriers, assessed by strong systemic biomarkers. Furthermore, consistently with the reduction of hepatic reactive oxygen and nitrogen species (RONS) levels, treatment with GT markedly reduced the HFD-induced increase in hepatic lipid peroxidation and hepatic steatosis. This research elucidates the importance of food supplementation with GT in the prevention and management of MetS.

Long-Term Ingestion of Sicilian Black Bee Chestnut Honey and/or D-Limonene Counteracts Brain Damage Induced by High Fat-Diet in Obese Mice

Obesity is linked to neurodegeneration, which is mainly caused by inflammation and oxidative stress. We analyzed whether the long-term intake of honey and/or D-limonene, which are known for their antioxidant and anti-inflammatory actions, when ingested separately or in combination, can counteract the neurodegeneration occurring in high fat diet (HFD)-induced obesity. After 10 weeks of HFD, mice were divided into: HFD-, HFD + honey (HFD-H)-, HFD + D-limonene (HFD-L)-, HFD + honey + D-limonene (HFD-H + L)-fed groups, for another 10 weeks. Another group was fed a standard diet (STD). We analyzed the brain neurodegeneration, inflammation, oxidative stress, and gene expression of Alzheimer's disease (AD) markers. The HFD animals showed higher neuronal apoptosis, upregulation of pro-apoptotic genes Fas-L, Bim P27 and downregulation of anti-apoptotic factors BDNF and BCL2; increased gene expression of the pro-inflammatory IL-1β, IL-6 and TNF-α and elevated oxidative stress markers COX-2, iNOS, ROS and nitrite. The honey and D-limonene intake counteracted these alterations; however, they did so in a stronger manner when in combination. Genes involved in amyloid plaque processing (APP and TAU), synaptic function (Ache) and AD-related hyperphosphorylation were higher in HFD brains, and significantly downregulated in HFD-H, HFD-L and HFD-H + L. These results suggest that honey and limonene ingestion counteract obesity-related neurodegeneration and that joint consumption is more efficacious than a single administration.

Opuntia ficus-indica Fruit: A Systematic Review of Its Phytochemicals and Pharmacological Activities

The use of Opuntia ficus-indica fruits in the agro-food sector is increasing for a multiplicity of players. This renewed interest is, in part, due to its organoleptic characteristics, nutritional value and health benefits. Furthermore, industries from different sectors intend to make use of its vast array of metabolites to be used in different fields. This trend represents an economic growth opportunity for several partners who could find new opportunities exploring non-conventional fruits, and such is the case for Opuntia ficus-indica. O. ficus-indica originates from Mexico, belongs to the Cactaceae family and is commonly known as opuntia, prickly pear or cactus pear. The species produces flowers, cladodes and fruits that are consumed either in raw or in processed products. Recent publications described that consumption of the fruit improves human health, exhibiting antioxidant activity and other relevant pharmacological activities through enzymatic and non-enzymatic mechanisms. Thus, we provide a systematic, scientific and rational review for researchers, consumers and other relevant stakeholders regarding the chemical composition and biological activities of O. ficus-indica fruits.

Redox Properties, Bioactivity and Health Effects of Indicaxanthin, a Bioavailable Phytochemical from Opuntia ficus indica, L.: A Critical Review of Accumulated Evidence and Perspectives

Phytochemicals from plant foods are considered essential to human health. Known for their role in the adaptation of plants to their environment, these compounds can induce adaptive responses in cells, many of which are directed at maintaining the redox tone. Indicaxanthin is a long-known betalain pigment found in the genus Opuntia of cactus pear and highly concentrated in the edible fruits of O. ficus indica, L. whose bioactivity has been overlooked until recently. This review summarizes studies conducted so far in vitro and in vivo, most of which have been performed in our laboratory. The chemical and physicochemical characteristics of Indicaxanthin are reflected in the molecule's reducing properties and antioxidant effects and help explain its ability to interact with membranes, modulate redox-regulated cellular pathways, and possibly bind to protein molecules. Measurement of bioavailability in volunteers has been key to exploring its bioactivity; amounts consistent with dietary intake, or plasma concentration after dietary consumption of cactus pear fruit, have been used in experimental setups mimicking physiological or pathophysiological conditions, in cells and in animals, finally suggesting pharmacological potential and relevance of Indicaxanthin as a nutraceutical. In reporting experimental results, this review also aimed to raise questions and seek insights for further basic research and health promotion applications.

Modulation of Human Motor Cortical Excitability and Plasticity by Opuntia Ficus Indica Fruit Consumption: Evidence from a Preliminary Study through Non-Invasive Brain Stimulation

Indicaxanthin (IX) from Opuntia Ficus Indica (OFI) has been shown to exert numerous biological effects both in vitro and in vivo, such as antioxidant, anti-inflammatory, neuro-modulatory activity in rodent models. Our goal was to investigate the eventual neuro-active role of orally assumed fruits containing high levels of IX at nutritionally-relevant amounts in healthy subjects, exploring cortical excitability and plasticity in the human motor cortex (M1). To this purpose, we applied paired-pulse transcranial magnetic stimulation and anodal transcranial direct current stimulation (a-tDCS) in basal conditions and followed the consumption of yellow cactus pear fruits containing IX or white cactus pear fruits devoid of IX (placebo). Furthermore, resting state-functional MRI (rs-fMRI) preliminary acquisitions were performed before and after consumption of the same number of yellow fruits. Our data revealed that the consumption of IX-containing fruits could specifically activate intracortical excitatory circuits, differently from the placebo-controlled group. Furthermore, we found that following the ingestion of IX-containing fruits, elevated network activity of glutamatergic intracortical circuits can homeostatically be restored to baseline levels following a-tDCS stimulation. No significant differences were observed through rs-fMRI acquisitions. These outcomes suggest that IX from OFI increases intracortical excitability of M1 and leads to homeostatic cortical plasticity responses.

Structural Effects on the Antioxidant Properties of Amino Acid Betaxanthins

Betaxanthins are natural products with high antioxidant and anti-inflammatory properties. Here, we describe the semisynthesis of twenty-one betaxanthins derived from proteinogenic amino acids, including the elusive betaxanthin of l-cysteine and two betaxanthins derived from l-lysine, and rationalize their antioxidant properties in mechanistic terms. The antioxidant capacity and redox potential of these betaxanthins were compared to those of model betaxanthins derived from dopamine, l-DOPA (L-3,4-dihydroxyphenylalanine), and pyrrolidine and structure-property relationships were established by using matched molecular pair analysis and a model developed using a genetic algorithm. Either a phenol or indole moiety enhance the antioxidant capacity of betaxanthins, which is overall much higher than that of their amino acid precursors and standard antioxidants, except for the cysteine-betaxanthin. The one-electron oxidation of amino acid betaxanthins produces radicals stabilized in multiple centers, as demonstrated by quantum chemical calculations.

Betalains: colours for human health

In the last years, the use of natural phytochemical compounds as protective agents in the prevention and treatment of obesity and the related-metabolic syndrome has gained much attention worldwide. Different studies have shown health benefits for many vegetables such Opuntia ficus-indica and Beta vulgaris and their pigments collectively referred as betalains. Betalains exert antioxidative, anti-inflammation, lipid lowering, antidiabetic and anti-obesity effects. This review summarizes findings in the literature and highlights the therapeutic potential of betalains and their natural source as valid alternative for supplementation in obesity-related disorders treatment. Further research is needed to establish the mechanisms through which these natural pigments exert their beneficial effects and to translate the promising findings from animal models to humans.

Engineering and Evaluation of Forcespun Gelatin Nanofibers as an Isorhamnetin Glycosides Delivery System

Opuntia ficus-indica (L.) Mill (OFI) is considered a natural source of bioactive phytochemicals, mainly isorhamnetin glycosides (IRGs). These compounds have demonstrated antioxidant, anti-inflammatory, and anticancer activities, among others. The development of a suitable delivery system for these compounds is needed to improve their chemical and biological stability. This study aimed to evaluate the feasibility of fabrication and characterization of IRG-loaded gelatin (GL) forcespun fibers and crosslinking with glutaraldehyde (GTA). Two different percentages (25% and 30% w/v) of GL were evaluated with 12% (w/v) OFI flour to obtain nanofibers GL/OFI1 and GL/OFI2, respectively. The morphology and physicochemical properties of the fibers were investigated. The results indicated that the diameters of the fibers were on the nanoscale. The amount of IRGs was determined using high-performance liquid chromatography (HPLC). The IRGs release and the cytocompatibility of the nanofibers were also evaluated. GL concentration significantly affected the IRG release. Among both nanofibers, the GL/OFI2 nanofiber achieved a cumulative IRGs release of 63% after 72 h. Both fibers were shown to be biocompatible with human skin/fibroblast cells. Specifically, GL/OFI1 nanofibers exhibited favorable features for their application as an extract-coupled release system. The IRGs-embedded GL nanofiber mats may become a good alternative for the delivery of phytochemicals for the health sector and biomedical applications.

Recent Advances in the Treatment of Insulin Resistance Targeting Molecular and Metabolic Pathways: Fighting a Losing Battle?

Diabetes Mellitus (DM) is amongst the most notable causes of years of life lost worldwide and its prevalence increases perpetually. The disease is characterized as multisystemic dysfunctions attributed to hyperglycemia resulting directly from insulin resistance (IR), inadequate insulin secretion, or enormous glucagon secretion. Insulin is a highly anabolic peptide hormone that regulates blood glucose levels by hastening cellular glucose uptake as well as controlling carbohydrate, protein, and lipid metabolism. In the course of Type 2 Diabetes Mellitus (T2DM), which accounts for nearly 90% of all cases of diabetes, the insulin response is inadequate, and this condition is defined as Insulin Resistance. IR sequela include, but are not limited to, hyperglycemia, cardiovascular system impairment, chronic inflammation, disbalance in oxidative stress status, and metabolic syndrome occurrence. Despite the substantial progress in understanding the molecular and metabolic pathways accounting for injurious effects of IR towards multiple body organs, IR still is recognized as a ferocious enigma. The number of widely available therapeutic approaches is growing, however, the demand for precise, safe, and effective therapy is also increasing. A literature search was carried out using the MEDLINE/PubMed, Google Scholar, SCOPUS and Clinical Trials Registry databases with a combination of keywords and MeSH terms, and papers published from February 2021 to March 2022 were selected as recently published papers. This review paper aims to provide critical, concise, but comprehensive insights into the advances in the treatment of IR that were achieved in the last months.