Lack of chemopreventive effects of α-eleostearic acid on 7,12-dimethylbenz[a]anthracene (DMBA) and 1,2-dimethylhydrazine (DMH)-induced mammary and colon carcinogenesis in female Sprague–Dawley rats

Conjugated Linolenic Acid (CLnA) vs Conjugated Linoleic Acid (CLA): A Comprehensive Review of Potential Advantages in Molecular Characteristics, Health Benefits, and Production Techniques

Conjugated linoleic acid (CLA) has been extensively characterized due to its many biological activities and health benefits, but conjugated linolenic acid (CLnA) is still not well understood. However, CLnA has shown to be more effective than CLA as a potential functional food ingredient. Current research has not thoroughly investigated the differences and advantages between CLnA and CLA. This article compares CLnA and CLA based on molecular characteristics, including structural, chemical, and metabolic characteristics. Then, the in vivo research evidence of CLnA on various health benefits is comprehensively reviewed and compared with CLA in terms of effectiveness and mechanism. Furthermore, the potential of CLnA in production technology and product protection is analyzed. In general, CLnA and CLA have similar physicochemical properties of conjugated molecules and share many similarities in regulation effects and pathways of various health benefits as well as in the production methods. However, their specific properties, regulatory capabilities, and unique mechanisms are different. The superior potential of CLnA must be specified according to the practical application patterns of isomers. Future research should focus more on the advantageous characteristics of different isomers, especially the effectiveness and safety in clinical applications in order to truly exert the potential value of CLnA.

Exploring the Influence of the Selected Conjugated Fatty Acids Isomers and Cancerous Process on the Fatty Acids Profile of Spleen

The spleen, traditionally associated with blood filtration and immune surveillance, has recently been recognized for its role in systemic lipid metabolism and potential influence on cancer development and progression. This study investigates effects of dietary supplements, specifically conjugated linolenic acids from pomegranate seed oil and bitter melon extract, on the fatty acid (FA) composition of the spleen in the context of cancerous processes. Advanced methods, including gas chromatography-mass spectrometry and silver ion-impregnated high-performance liquid chromatography, were employed to analyze the spleen's FA profile. Our research uncovered that dietary supplementation leads to alterations in the spleen's FA profile, especially under the carcinogenic influence of 7,12-dimethylbenz[a]anthracene. These changes did not align with a simple protective or anti-carcinogenic pattern, as previously suggested in in vitro studies. We observed shifts in conjugated FA isomer concentrations and variations in desaturase activities, suggesting disrupted lipid metabolism in cancerous conditions. The findings underscore the spleen's vital role in lipid metabolism within the body's systemic health framework, highlighting the complexity of dietary supplements' impact on FA profiles in the spleen and their potential implications in cancer progression and treatment. This study adds valuable insight into the complex interplay between diet, disease, and metabolic regulation, particularly in cancerous environments.

Oxysterols and lipidomic profile of myocardium of rats supplemented with pomegranate seed oil and/or bitter melon aqueous extract - Cardio-oncological animal model research

A close link between cardiovascular diseases and cancer results from sharing the same modifiable risk factors (e.g. nutritional) and cardiotoxicity of anti-cancerous therapies. It justifies cardio-oncological preliminary studies on dietary factors, especially on those of possible anti-carcinogenic or cardioprotective properties. The main purpose was to evaluate the effect of pomegranate seed oil (PSO) and/or bitter melon extract (BME) supplementation of the diet of female rats suffering from mammary tumors on lipidomic profile (expressed as fatty acids, conjugated fatty acids (CFA), malondialdehyde (MDA), cholesterol and oxysterols content) of cardiac tissue. Total lipidomic profile and intensity of lipid peroxidation in hearts of DMBA-treated Sprague-Dawley rats and their healthy equivalents, both obtaining diet supplementation, were evaluated with different chromatographic techniques coupled with appropriate detection systems (GC-MS, GC-TOFMS, Ag+-HPLC-DAD, UF-HPLC-DAD). Dietary modifications neither diminished breast cancer incidence nor exerted explicit cardio-protective influence, however, they diminished cholesterol content, i.a. because of inhibition of the endogenous conversion of squalene to cholesterol in cardiac tissue. CFA were incorporated into cardiac tissue to a lesser extent in the cancerous process. PSO and BME anti-oxidant properties in pathological condition were only slightly reflected in MDA levels but not in oxysterols formation. Obtained results indicate considerable changes in dietary supplements' biological activity in pathological conditions and the need for clear distinction of drugs and dietary supplements, which is of utmost importance, especially for cancer survivors.

Mammary cancer risk and serum lipid profile of rats supplemented with pomegranate seed oil and bitter melon extract

The objective of the present study was to determine the influence of dietary supplementation with pomegranate seed oil (PSO) and/or an aqueous extract of dried bitter melon fruits (BME) on breast cancer risk and fatty acid profile in serum of female rats with chemical carcinogen-inflicted mammary tumours. Sprague-Dawley rats (n = 96) were fed control diet or experimental diets supplemented with 0.15 ml PSO/day, BME or jointly PSO and BME. After 21 weeks mammary tumours were subjected to histopathological examination and in serum fatty acids, 8-isoprostaglandin F_2α content and indices of desaturases activity were analysed. Supplementation of the diet with PSO and BME did not inhibit the breast cancer formation. Conjugated linolenic acids (CLnA), present in PSO, were converted into cis-9, trans-11 conjugated linoleic acid (CLA), however, its content was lower in groups treated with a carcinogen. A similar tendency was observed for the content of SFA, MUFA, PUFA, 8-iso PGF_2α and the activity of Δ⁶-desaturase. Enhanced pro-carcinogenic effect of 7,12-dimethylbenz[a]anthracene (DMBA), caused by applied supplements, may be a result of their influence on DMBA metabolism.

Sources and Bioactive Properties of Conjugated Dietary Fatty Acids

The group of conjugated fatty acids known as conjugated linoleic acid (CLA) isomers have been extensively studied with regard to their bioactive potential in treating some of the most prominent human health malignancies. However, CLA isomers are not the only group of potentially bioactive conjugated fatty acids currently undergoing study. In this regard, isomers of conjugated α-linolenic acid, conjugated nonadecadienoic acid and conjugated eicosapentaenoic acid, to name but a few, have undergone experimental assessment. These studies have indicated many of these conjugated fatty acid isomers commonly possess anti-carcinogenic, anti-adipogenic, anti-inflammatory and immune modulating properties, a number of which will be discussed in this review. The mechanisms through which these bioactivities are mediated have not yet been fully elucidated. However, existing evidence indicates that these fatty acids may play a role in modulating the expression of several oncogenes, cell cycle regulators, and genes associated with energy metabolism. Despite such bioactive potential, interest in these conjugated fatty acids has remained low relative to the CLA isomers. This may be partly attributed to the relatively recent emergence of these fatty acids as bioactives, but also due to a lack of awareness regarding sources from which they can be produced. In this review, we will also highlight the common sources of these conjugated fatty acids, including plants, algae, microbes and chemosynthesis.

Conjugated linolenic acids and their bioactivities: a review

Conjugated linolenic acid (CLNA) is a mixture of positional and geometric isomers of octadecatrienoic acid (α-linolenic acid, cis9,cis12,cis15-18:3 n-3) found in plant seeds. Three 8,10,12-18:3 isomers and four 9,11,13-18:3 isomers have been reported to occur naturally. CLNA isomers such as punicic acid, α-eleostearic acid and jacaric acid have been attributed to exhibit several health benefits that are largely based on animal and in vitro studies. This review has summarized and updated the evidence regarding the metabolism and bioactivities of CLNA isomers, and comprehensively discussed the recent studies on the effects of anti-carcinogenic, lipid metabolism regulation, anti-inflammatory, anti-obese and antioxidant activities of CLNA isomers. The available results may provide a potential application for CLNA isomers from natural sources, especially edible plant seeds, as effective functional food ingredients and dietary supplements for the above mentioned disease management. Further research, especially human randomized clinical trials, is warranted to investigate the detailed physiological effects, bioactivity and molecular mechanism of CLNA.

Growth inhibition and apoptotic effect of alpha-eleostearic acid on human breast cancer cells

Alpha-eleostearic acid (α-ESA) is a natural and biologically active compound which possesses potent antioxidant and anti-tumor activity. The purpose of this study was to confirm the anticancer activity of α-ESA against human breast cancer cells and to further elucidate its mechanism of activity. Human breast cancer cells and normal liver cells were used for in-vitro tests of the anticancer activity of α-ESA, including cytotoxicity, colony formation inhibition, EdU incorporation, AO/EB staining of apoptotic cells, cell cycle distribution through flow cytometry, and PPARγ, p21, Bax, p53, and caspase-3 mRNA expressions through RT-PCR. After α-ESA treatment, the proliferation, colony formation, and EdU labeling indices of cancer cells decreased (p < 0.05), while the AO/EB-stained apoptotic cells increased (p < 0.05). By FCM analysis, the apoptotic indices increased (p < 0.01), and the cell population decreased in S phase (p < 0.01) and increased in G(2)/M phase (p < 0.05) in α-ESA treated cancer cells. RT-RCR showed that α-ESA significantly increased the expression levels of PPARγ, p21, Bax, p53, and caspase-3 mRNA. The findings in these studies suggested that α-ESA exhibited a potential cytotoxicity and apoptosis induction effect on human breast cancer cells, with little effect on normal cells at certain concentrations. The mechanism for such effects might be associated with the inhibition of DNA synthesis, induction of apoptosis, and cell cycle arrest of cancer cells through up-regulation of PPARγ, p21, Bax, p53, and caspase-3 expressions.

The health promoting properties of the conjugated isomers of α-linolenic acid

The bioactive properties of the conjugated linoleic acid (CLA) isomers have long been recognised and are the subject of a number of excellent reviews. However, despite this prominence the CLA isomers are not the only group of naturally occurring dietary conjugated fatty acids which have shown potent bioactivity. In a large number of in vitro and in vivo studies, conjugated α-linolenic acid (CLNA) isomers have displayed potent anti-inflammatory, immunomodulatory, anti-obese and anti-carcinogenic activity, along with the ability to improve biomarkers of cardio-vascular health. CLNA isomers are naturally present in high concentrations in a large variety of seed oils but can also be produced in vitro by strains of lactobacilli and bifidobactena through the activity of the enzyme linoleic acid isomerase on α-linolenic acid. In this review, we will address the possible therapeutic roles that CLNA may play in a number of conditions afflicting Western society and the mechanisms through which this activity is mediated.