Virgin coconut oil reverses hepatic steatosis by restoring redox homeostasis and lipid metabolism in male Wistar rats

Coconut oil affects aging-related changes in Mongolian gerbil liver morphophysiology

Aging causes changes in liver morphophysiology, altering hepatocyte morphology and organ function. Due to its antioxidant and anti-inflammatory properties, coconut oil has been used as a therapeutic agent in diets, in an attempt to attenuate alterations in the liver naturally caused by aging. Herein, we evaluated the effects of coconut oil consumption during aging on Mongolian gerbil liver morphophysiology. The animals were divided into three experimental groups: the gerbils in the Adult Control Group (AC) were euthanized at 3 months of age, the gerbils in the Old Control Group (OC) at 15 months of age, and the gerbils in the Coconut Oil Group (CO) received 0.1 ml/day of coconut oil for 12 months and were euthanized at 15 months of age. Prolonged consumption of coconut oil during aging prevented the animals and the liver from gaining mass. However, the other results showed that coconut oil intensified the morphophysiological alterations of aging, promoting an increase in the hepatocyte cytoplasm and nuclei. In addition, an increase in blood vessels, reticular fibers, lipid droplets, and lipofuscin granules were observed in the CO group. Finally, the results also demonstrated that coconut oil promotes an increase in lipid peroxidation, indicated by an increase in MDA levels. We therefore conclude that coconut oil has the potential to intensify the morphophysiological alterations that occur in the liver during aging.

Virgin coconut oil mitigates ageing-associated oxidative stress and dyslipidaemia in male Wistar rats

BACKGROUND AND AIM

Ageing often leads to the deterioration of physiological functions, including a decline in antioxidant defences, which can result in various health complications. Exogenous antioxidants have been recognised for their potential to alleviate these age-related health complications. Virgin coconut oil (VCO), known for its antioxidant, anti-inflammatory and anti-lipidemic efficacies, has gained recognition as a functional food with promising benefits. However, the safety of VCO consumption among individuals of the aged and diseased population remains to be fully established.

METHODS AND RESULTS

Five experimental groups were established, consisting of one control group and four groups administered either "2 mL" or "4 mL" per kg body weight of "HP-VCO" or "F-VCO" daily for six weeks. Body weight, water, and feed intake were monitored. After six weeks, animals were euthanized, blood and organs were collected for analysis. Oxidative stress and dyslipidemia markers were analysed, and liver tissues underwent histological examination. HP-VCO-administered animals exhibited increased serum total cholesterol and triglycerides, whereas F-VCO-fed animals showed reduced triglyceride levels. LDL-cholesterol levels decreased in all VCO-fed groups, accompanied by increased HDL-cholesterol levels. Additionally, all treated groups showed a slight increase in the HMG Co. A/mevalonate ratio. Both VCO-fed animals displayed elevated reduced glutathione levels and reduced glutathione - S transferase activity. Consistent with these findings, decreased conjugated dienes and thiobarbituric acid reactive substances confirmed the improved redox status.

CONCLUSION

The study indicated that F-VCO is advantageous over VCO prepared by hot pressing as it offers protection against oxidative stress and related degenerative diseases.

A high-fat diet supplemented with medium-chain triglycerides ameliorates hepatic steatosis by reducing ceramide and diacylglycerol accumulation in mice

Non-alcoholic fatty liver disease (NAFLD) is projected to be the most common chronic liver disease worldwide and is closely linked to obesity, insulin resistance and type 2 diabetes. Currently, no pharmacological treatments are available to treat NAFLD, and lifestyle modification, including dietary interventions, is the only remedy. Therefore, we conducted a study to determine whether supplementation with medium-chain triglycerides (MCTs), containing a mixture of C8 and C10 (60/40), attenuates NAFLD in obese and insulin-resistant mice. To achieve that, we fed C57BL/6 male mice a high-fat diet (HFD) for 12 weeks to induce obesity and hepatic steatosis, after which obese mice were assigned randomly either to remain on the HFD or to transition to an HFD supplemented with MCTs (HFD + MCTs) or a low-fat diet (LFD) for 6 weeks as another dietary intervention model. Another group of mice was kept on an LFD throughout the study and used as a lean control group. Obese mice that transitioned to HFD + MCTs exhibited improvement in glucose and insulin tolerance tests, and the latter improvement was independent of changes in adiposity when compared with HFD-fed mice. Additionally, supplementation with MCTs significantly reduced hepatic steatosis, improved liver enzymes and decreased hepatic expression of inflammation-related genes to levels similar to those observed in obese mice transitioned to an LFD. Importantly, HFD + MCTs markedly lowered hepatic ceramide and diacylglycerol content and prevented protein kinase C-ε translocation to the plasma membrane. Our study demonstrated that supplementation with MCTs formulated mainly from C8 and C10 effectively ameliorated NAFLD in obese mice.

In vivo antioxidant and hypoglycaemic potentials of Rivina humilis extract against streptozotocin induced diabetes and its complications in wistar rats

Purpose

This current research study was designed to investigate beneficial effects of R. humilis (Rivina humilis) against streptozotocin-induced diabetic rats.

Methods

The R. humilis ethanol extract was prepared using soxhlet and its phenol content was determined. The type-2 diabetes was induced in rats by giving fructose mixed drinking water and single dose of streptozotocin. Oral glucose tolerance test (OGTT) was performed after 72 h of streptozotocin to check ability of extract to utilize oral glucose load with 2 h. The extract was also tested for its potentials to reduce blood glucose (BGL) and diabetic complications by administering to diabetic rats for 21 days. Blood glucose was determined on day 1, 7, 14 and 21. At 21st day, blood samples were collected from experimental rats were euthanized to collect pancreas and liver. Liver and kidney function tests, HbAc1 and lipid profile was established from blood samples. Pancreas was subjected to histopathological examination and liver was used to determine antioxidant enzymes. In vitro study was done to investigate the effect of extract on glucose utilization by rat hemidiaphragm.

Results

In OGTT, administration of extract could stimulate glucose utilization which was witnessed by significant BGL reduction at 90 and 120 min in therapeutic groups compare to diabetics. In chronic study, we observed significant reduction in BGL on 21st day and all tests performed to determine liver and kidney function, HbAc1, vitamin E were normal in extract treated groups. There was significant increase in liver antioxidant enzymes in therapeutic groups which revealed regeneration of β-cells in therapeutic groups.

Conclusion

The results of research demonstrated significant antidiabetic potentials in R. humilis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-023-01258-6.

Nutrients, Physical Activity, and Mitochondrial Dysfunction in the Setting of Metabolic Syndrome

Metabolic syndrome (MetS) is a cluster of metabolic risk factors for diabetes, coronary heart disease, non-alcoholic fatty liver disease, and some tumors. It includes insulin resistance, visceral adiposity, hypertension, and dyslipidemia. MetS is primarily linked to lipotoxicity, with ectopic fat deposition from fat storage exhaustion, more than obesity per se. Excessive intake of long-chain saturated fatty acid and sugar closely relates to lipotoxicity and MetS through several pathways, including toll-like receptor 4 activation, peroxisome proliferator-activated receptor-gamma regulation (PPARγ), sphingolipids remodeling, and protein kinase C activation. These mechanisms prompt mitochondrial dysfunction, which plays a key role in disrupting the metabolism of fatty acids and proteins and in developing insulin resistance. By contrast, the intake of monounsaturated, polyunsaturated, and medium-chain saturated (low-dose) fatty acids, as well as plant-based proteins and whey protein, favors an improvement in sphingolipid composition and metabolic profile. Along with dietary modification, regular exercises including aerobic, resistance, or combined training can target sphingolipid metabolism and improve mitochondrial function and MetS components. This review aimed to summarize the main dietary and biochemical aspects related to the physiopathology of MetS and its implications for mitochondrial machinery while discussing the potential role of diet and exercise in counteracting this complex clustering of metabolic dysfunctions.

Virgin Coconut Oil: A Dietary Intervention for Dyslipidaemia in Patients with Diabetes Mellitus

Hyperlipidaemia is causally related to coronary artery diseases (CAD) and peripheral artery diseases (PAD) in people with Diabetes Mellitus (DM). An in vivo study confirmed that virgin coconut oil (VCO) could maintain levels of lipids in the blood as effectively as conventional therapy. Therefore, this study aimed to determine the effect of VCO on the lipid profiles and ankle-brachial index (ABI) of patients with DM. In this experimental study with pre- and post-test design and a control group, the participants were selected purposively. The ABI was evaluated on the first visit. Baseline lipid profile readings were taken. Each participant took 1.2 mL/kgBW of VCO daily and divided it into three doses. After 30 days of taking VCO, laboratory examinations and ABI were repeated, and adverse events were evaluated. The dependent t-test and Wilcoxon sign rank test with a significance level of α ≤ 0.05 showed a significant decrease in low-density lipoprotein (LDL) (p = 0.002), a significant increase in high-density lipoprotein (HDL) levels (p = 0.031), a significant decrease in energy intake (p = 0.046) and cholesterol intake (p = 0.023) at the endpoint in the VCO group. In conclusion, this therapy is beneficial for maintaining lipid profile when combined with dietary therapy. Future studies should investigate the duration and dosage of VCO on patients to maintain lipid-linked protein.

Non alcoholic palm nectar from Cocos nucifera as a promising nutraceutical preparation

Nonalcoholic Palm Nectar from Cocos nucifera (NPNC), a bio-refresher obtained from the juvenile inflorescence of coconut palm; is prominent as a nutritional health drink. The aim of this study was to investigate the nutritional and medicinal properties of NPNC and its products; sugar (NPNCS) and honey (NPNCH). The collected samples were subjected to physicochemical evaluations such as pH, Titrable Acidity, Total Soluble Solids, and Ash value, using standard techniques. The analysis revealed the suitability of NPNC as a natural health drink over conventionally available beverage. The elemental compositions of the samples were determined by using Inductive Coupled Plasma-Atomic Emission Spectrometry and demonstrated that NPNCH is enriched with iron and NPNCS with calcium. Vitamin C present in the samples was determined by using 2,6-Dichlorophenol indophenol redox titration method. Hydrolysable polyphenols, tannins, and flavonoids are determined by Folin-Ciocalteu, by Folin-Denis's technique and by aluminium chloride colorimetric methods, respectively. In NPNC, the dominance of Vitamin C as antioxidant is observed. Diuretic activity of samples was determined by Lipschitz method, and the results revealed that NPNC exhibited significant diuretic activity, comparable with furosemide. Immunomodulatory activities of the samples were evaluated by using indirect hemagglutination test and by using delayed type hypersensitivity (DTH) response. NPNC, NPNCS, and NPNCH exhibited stimulatory effect on humoral and cell-mediated immunity, which is comparable with that of standard immunomodulator levamizole. Subacute toxicity studies of selected samples were done in Wistar rats and the results proved the boicompatibility of the samples without systemic toxic effects. PRACTICAL APPLICATIONS: The use of commercially available carbonated beverages and energy drinks in young adults are associated with negative health outcomes with increased incidence of diabetes, sleep disturbances, and dental problems. Even though, such complications are there, the energy drink industries have grown dramatically accounting for major percentage of market sale. Researchers are in search for natural health drinks with some medicinal value to avoid the negative impact on consumers' health. Nonalcoholic Palm Nectar from Cocos nucifera (NPNC) is considered as zero alcoholic natural health drink. The focus of this study is to reveal the potential medicinal properties of NPNC and its products; honey (NPNCH) and sugar (NPNCS). If the nutritional and medicinal values of the selected preparations from natural sources can be proved with scientific evidence, its ability to beat commercially available carbonated beverages and energy drinks with negative health consequences may get widespread acceptance.

The relationship between flavor formation, lipid metabolism, and microorganisms in fermented fish products

Traditional fermented fish products are favored due to their unique flavors. The fermentation process of fish is accompanied by the formation of flavor substances through a complex metabolic reaction of microorganisms, especially lipolysis and lipid oxidation. However, it is difficult to precisely control the reaction of microorganisms during the fermentation process in modern industrial production, and fermented fish products have lost their traditional characteristic flavors. The purpose of this review is to summarize the different kinds of fermented fish, core microorganisms in it, and flavor formation mechanisms, providing guidance for industrial cultural starters. Future research on the flavor formation mechanism is necessary to confirm the relationship between flavor formation, lipid metabolism, and microorganisms to ensure stable flavor and safety, and to elucidate the mechanism directly toward industrial application.

Consumption of soybean or olive oil at recommended concentrations increased the intestinal microbiota diversity and insulin sensitivity and prevented fatty liver compared to the effects of coconut oil

Diets rich in mono or polyunsaturated fats have been associated with a healthy phenotype, but there is controversial evidence about coconut oil (CO), which is rich in saturated medium-chain fatty acids. Therefore, the purpose of the present work was to study whether different types of oils rich in polyunsaturated (soybean oil, SO), monounsaturated (olive oil, OO), or saturated fatty acids (coconut oil, CO) can regulate the gut microbiota, insulin sensitivity, inflammation, mitochondrial function in wild type and PPARα KO mice. The group that received SO showed the highest microbial diversity, increase in Akkermansia muciniphila, high insulin sensitivity and low grade inflammation, The OO group showed similar insulin sensitivity and insulin signaling than SO, increase in Bifidobacterium, increase in fatty acid oxidation and low grade inflammation. The CO consumption led to the lowest bacterial diversity, a 9-fold increase in the LPS concentration leading to metabolic endotoxemia, hepatic steatosis, increased lipogenesis, highest LDL-cholesterol concentration and the lowest respiratory capacity and fatty acid oxidation in the mitochondria. The absence of PPARα decreased alpha diversity and increased LPS concentration particularly in the CO group, and increased insulin sensitivity in the groups fed SO or OO. These results indicate that consuming mono or polyunsaturated fatty acids produced health benefits at the recommended intake but a high concentration of oils (three times the recommended oil intake in rodents) significantly decreased the microbial alpha-diversity independent of the type of oil.

Variations in natural polyphenols determine the anti-inflammatory potential of virgin coconut oils

Virgin coconut oil (VCO), an edible oil prepared from fresh coconut kernel by natural or mechanical means without undergoing chemical refining, has been in the limelight of research as functional food oil. The phenolic components in VCO have been accredited with these pharmacological benefits. The present study compared the phenolic constituents of freshly prepared fermentation processed (FVCO) and hot-pressed VCO (HVCO) and their anti-inflammatory efficacies. The biochemical analysis documented quantitative variation in the phenolic content, being higher in HVCO than FVCO (40.03 ± 5.8 µg and 25.55 ± 5.8 µg/mL of oil, respectively). In vitro studies observed nitric oxide radical scavenging efficacy (IC₅₀ value of 14.84 ± 0.81 µg/mL) for HVCO polyphenols, which shows higher inhibition efficacy than FVCO (29.41 ± 1.7 µg/mL). In dextran and formalin mediated acute and chronic inflammation in mice, HVCO displayed more protective efficacy (40.5 and 46.4% inhibition) than FVCO (33.3 and 43.8% inhibition), which is similar to the standard diclofenac (55.6 and 59.8% inhibition). The study, thus, concludes that compared to FVCO, HVCO is a more active anti-inflammatory agent. PRACTICAL APPLICATION: Virgin coconut oil, a widely used edible oil in South Asian countries, has been shown to have health benefits possibly exerted by the natural phenolics it contains. However, different modes of preparations of VCO determine the phenolic combinations and efficacy as well. Our study compared two different VCO preparations and suggests that the VCO prepared by the traditional way (HVCO) is pharmacologically potent than that prepared by simple fermentation process (FVCO) in reducing inflammation. The efficacy is attributed to the variations in phenolic profile revealed by LC-MS analysis. Hence, the current study suggests HVCO as a potential food supplement that can reduce the incidence of degenerative diseases.

Chemical composition and health benefits of coconut oil: an overview

Coconut oil is an integral part of Sri Lankan and many South Asian diets. Initially, coconut oil was classified along with saturated fatty acid food items and criticized for its negative impact on health. However, research studies have shown that coconut oil is a rich source of medium-chain fatty acids. Thus, this has opened new prospects for its use in many fields. Beyond its usage in cooking, coconut oil has attracted attention due to its hypocholesterolemic, anticancer, antihepatosteatotic, antidiabetic, antioxidant, anti-inflammatory, antimicrobial and skin moisturizing properties. Despite all the health benefits, consumption of coconut oil is still underrated due to a lack of supportive scientific evidence. Even though studies done in Asian countries claim a favorable impact on cardiac health and serum lipid profile, the limitations in the number of studies conducted among Western countries impede the endorsement of the real value of coconut oil. Hence, long-term extensive studies with proper methodologies are suggested to clear all the controversies and misconceptions of coconut oil consumption. This review discusses the composition and functional properties of coconut oils extracted using various processing methods. © 2020 Society of Chemical Industry.

Low-Dose Coconut Oil Supplementation Induces Hypothalamic Inflammation, Behavioral Dysfunction, and Metabolic Damage in Healthy Mice

SCOPE

Coconut oil (CO) diets remain controversial due to the possible association with metabolic disorder and obesity. This study investigates the metabolic effects of a low amount of CO supplementation.

METHODS AND RESULTS

Swiss male mice are assigned to be supplemented orally during 8 weeks with 300 µL of water for the control group (CV), 100 or 300 µL of CO (CO100 and CO300) and 100 or 300 µL of soybean oil (SO; SO100 and SO300). CO led to anxious behavior, increase in body weight gain, and adiposity. In the hypothalamus, CO and SO increase cytokines expression and pJNK, pNFKB, and TLR4 levels. Nevertheless, the adipose tissue presented increases macrophage infiltration, TNF-α and IL-6 after CO and SO consumption. IL-1B and CCL2 expression, pJNK and pNFKB levels increase only in CO300. In the hepatic tissue, CO increases TNF-α and chemokines expression. Neuronal cell line (mHypoA-2/29) exposed to serum from CO and SO mice shows increased NFKB migration to the nucleus, TNF-α, and NFKBia expression, but are prevented by inhibitor of TLR4 (TAK-242).

CONCLUSIONS

These results show that a low-dose CO changes the behavioral pattern, induces inflammatory pathway activation, TLR4 expression in healthy mice, and stimulates the pro-inflammatory response through a TLR4-mediated mechanism.

Impaired mitochondrial medium-chain fatty acid oxidation drives periportal macrovesicular steatosis in sirtuin-5 knockout mice

Medium-chain triglycerides (MCT), containing C8-C12 fatty acids, are used to treat several pediatric disorders and are widely consumed as a nutritional supplement. Here, we investigated the role of the sirtuin deacylase Sirt5 in MCT metabolism by feeding Sirt5 knockout mice (Sirt5KO) high-fat diets containing either C8/C10 fatty acids or coconut oil, which is rich in C12, for five weeks. Coconut oil, but not C8/C10 feeding, induced periportal macrovesicular steatosis in Sirt5KO mice. 14C-C12 degradation was significantly reduced in Sirt5KO liver. This decrease was localized to the mitochondrial β-oxidation pathway, as Sirt5KO mice exhibited no change in peroxisomal C12 β-oxidation. Endoplasmic reticulum ω-oxidation, a minor fatty acid degradation pathway known to be stimulated by C12 accumulation, was increased in Sirt5KO liver. Mice lacking another mitochondrial C12 oxidation enzyme, long-chain acyl-CoA dehydrogenase (LCAD), also developed periportal macrovesicular steatosis when fed coconut oil, confirming that defective mitochondrial C12 oxidation is sufficient to induce the steatosis phenotype. Sirt5KO liver exhibited normal LCAD activity but reduced mitochondrial acyl-CoA synthetase activity with C12. These studies reveal a role for Sirt5 in regulating the hepatic response to MCT and may shed light into the pathogenesis of periportal steatosis, a hallmark of human pediatric non-alcoholic fatty liver disease.

Lauric Acid versus Palmitic Acid: Effects on Adipose Tissue Inflammation, Insulin Resistance, and Non-Alcoholic Fatty Liver Disease in Obesity

Simple Summary

The aim of this study was to compare the effect of palmitic acid (PA), a long-chain fatty acid, and lauric acid (LA), a medium-chain fatty acid, on obesity-related metabolic disorders. We used a mouse model of diet-induced obesity and fed them a modified high fat diet supplemented with 3% PA or LA for 12 wk. An LA diet led to an increase in visceral fat mass with a reduction in inflammation compared to the PA diet. We also noted that PA significantly increased systemic insulin resistance whereas LA showed only a trend towards an increase compared to lean control mice. The expression of a protein involved in muscle glucose uptake was higher in LA-treated mice compared to the PA-treated group, indicating improved muscle glucose uptake in LA-fed mice. Analysis of liver samples showed that hepatic steatosis was higher in both PA and LA-fed mice compared to lean controls. Markers of liver inflammation were not altered significantly in mice receiving PA or LA. Our data suggest that compared to PA, LA exerts less adverse effects on metabolic disorders and this could be due to the differential effects of these fatty acids in fat and muscle.

Abstract

Coconut oil, rich in medium-chain saturated fatty acids (MCSFA), in particular, lauric acid (LA), is known to exert beneficial metabolic effects. Although LA is the most abundant saturated fatty acid in coconut oil, the specific role of LA in altering obesity-related metabolic disorders remains unknown. Here, we examined the effects of supplementing a high fat (HF) diet with purified LA on obesity-associated metabolic derangements in comparison with palmitic acid (PA), a long-chain saturated fatty acid. Male C57BL/6 mice were fed a control chow diet (CD) or an HF diet supplemented with 3% LA (HF + LA) or PA (HF + PA) for 12 wk. Markers of adipose tissue (AT) inflammation, systemic insulin resistance (IR), and hepatic steatosis, were assessed. The body weight and total fat mass were significantly higher in both HF + LA and HF + PA diet-fed groups compared to CD controls. However, the visceral adipose tissue (VAT) mass was significantly higher (p < 0.001) in HF + LA-fed mice compared to both CD as well as HF + PA-fed mice. Interestingly, markers of AT inflammation were promoted to a lesser extent in HF + LA-fed mice compared to HF + PA-fed mice. Thus, immunohistochemical analysis of VAT showed an increase in MCP-1 and IL-6 staining in HF + PA-fed mice but not in HF + LA-fed mice compared to CD controls. Further, the mRNA levels of macrophage and inflammatory markers were significantly higher in HF + PA-fed mice (p < 0.001) whereas these markers were increased to a lesser extent in HF + LA-fed group. Of note, the insulin tolerance test revealed that IR was significantly increased only in HF + PA-fed mice but not in HF + LA-fed group compared to CD controls. While liver triglycerides were increased significantly in both HF + PA and HF + LA-fed mice, liver weight and plasma markers of liver injury such as alanine aminotransferase and aspartate aminotransferase were increased significantly only in HF + PA-fed mice but not in HF + LA-fed mice. Taken together, our data suggest that although both LA and PA increased AT inflammation, systemic IR, and liver injury, the extent of metabolic derangements caused by LA was less compared to PA in the setting of high fat feeding.

Hot-processed virgin coconut oil abrogates cisplatin-induced nephrotoxicity by restoring redox balance in rats compared to fermentation-processed virgin coconut oil

Virgin coconut oil (VCO) is a functional food oil prepared from fresh coconut kernel either by hot-processed (HPVCO) or fermentation-processed (FPVCO). The FPVCO has been widely explored for its pharmacological efficacy; while HPVCO, which has traditional uses, is less explored. The present study compared the phenolic content and nephroprotective effect of both these oils in male Wistar rats. In vitro antioxidant activity was estimated in terms of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ferric reducing antioxidant power and ex vivo lipid peroxidation inhibition. In in vivo models, the rats were pretreated orally with of FPVCO or HPVCO (doses 2 and 4 mL/kg) for seven days and nephrotoxicity was induced by the single intraperitoneal injection of cisplatin (10 mg/kg). The results indicated significantly higher polyphenol content in HPVCO (400.3 ± 5.8 µg/mL) than that of FPVCO (255.5 ± 5.8 µg/mL). Corroborating with the increased levels of polyphenols, the in vitro antioxidant potential was significantly higher in the HPVCO. Further, pretreatment with these VCO preparations protected the rats against the cisplatin-induced nephrotoxicity, with higher extent by HPVCO. The renal function markers like urea, creatinine and total bilirubin were significantly reduced (p < 0.05) with HPVCO pretreatment. Apart from the nephroprotective effects, HPVCO also abrogated the cisplatin-induced myelosuppression and hepatotoxicity. The restoration of hepato-renal function by the pretreatment of HPVCO was well corroborated with the improvement in functional antioxidants and subsequent reduction in renal lipid peroxidation. Supporting these observations, renal histology revealed reduced glomerular/tubular congestion and necrosis. Thus, the study concludes that HPVCO may be better functional food than FPVCO.

Toll-like Receptors as a Novel Therapeutic Target for Natural Products Against Chronic Diseases

Toll-like receptors (TLR) are one among the initial responders of the immune system which participate in the activation inflammatory processes. Several different types of TLR such as TLR2, TLR4, TLR7 and TLR9 have been identified in various cell types, each having distinct ligands like lipids, lipoproteins, nucleic acids and proteins. Though its prime concern is xenobiotic defences, TLR signalling has also recognized as an activator of inflammation and associated development of chronic degenerative disorders (CDDs) including obesity, type 2 diabetes mellitus (T2DM), fatty liver disease, cardiovascular and neurodegenerative disorders as well as various types of cancers. Numerous drugs are in use to prevent these disorders, which specifically inhibit different pathways associated with the development of CDDs. Compared to these drug targets, inhibition of TLR, which specifically responsible for the inflammatory insults has proven to be a better drug target. Several natural products have emerged as inhibitors of CDDs, which specifically targets TLR signalling, among these, many are in the clinical trials. This review is intended to summarize the recent progress on TLR association with CDDs and to list possible use of natural products, their combinations and their synthetic derivative in the prevention of TLR-driven CDD development.

Resveratrol intake during pregnancy and lactation re-programs adiposity and ameliorates leptin resistance in male progeny induced by maternal high-fat/high sucrose plus postnatal high-fat/high sucrose diets via fat metabolism regulation

Background

Maternal obesity is an emerging problem in the modern world. Growing evidence suggests that intrauterine high-fat (HF) exposure may predispose progeny to subsequent metabolic challenges. Progeny born to mothers who ate an HF diet also tends to eat an HF diet when growing and aggravate metabolic issues. Thus, the generational transmission of obesity is cyclical. Developing a strategy to prevent the occurrence of metabolic syndrome related to prenatal and/or postnatal HF diet is important. In this study, the reprogramming effects of maternal resveratrol treatment for the progeny with maternal HF/postnatal HF diets were investigated.

Methods

Sprague-Dawley dams were fed either a control or a high-fat/high sucrose diet (HFHS) from mating to lactation. After weaning, the progeny was fed chow or an HF diet. Four experimental groups were yielded: CC (maternal/postnatal control diet), HC (maternal HF/postnatal control diet), CH (maternal control/postnatal HFHS diet), and HH (maternal/postnatal HFHS diet). A fifth group (HRH) received a maternal HFHS diet plus maternal resveratrol treatment and a postnatal chow diet to study the effects of maternal resveratrol therapy.

Results

Maternal resveratrol treatment lessened the weight and adiposity of progeny that were programmed by combined prenatal and postnatal HFHS diets. Maternal resveratrol therapy ameliorated the decreased abundance of the sirtuin 1 (SIRT1) enzyme in retroperitoneal tissue and the altered leptin/soluble leptin receptor ratio of progeny. Maternal resveratrol therapy also decreased lipogenesis and increased lipolysis for progeny.

Conclusions

Maternal resveratrol intervention can prevent adiposity programmed by maternal and postnatal HFHS diets by inducing lipid metabolic modulation. This study offers a novel reprogramming role for the effect of maternal resveratrol supplements against obesity.

Virgin Coconut Oil Associated with High-Fat Diet Induces Metabolic Dysfunctions, Adipose Inflammation, and Hepatic Lipid Accumulation

Obesity reaches an epidemic level worldwide, and this condition is associated with chronic low-grade inflammation and secondary comorbidities, largely driven by global changes in lifestyle and diet. Various dietary approaches are proposed for the obesity treatment and its associated metabolic disorders. Good taste, antioxidant functions, and vitamins have been attributed to virgin coconut oil (VCO). However, VCO contains a large amount of saturated fatty acids, and the consumption of this fat is associated with a number of secondary diseases. We evaluate the effects of VCO supplementation on biochemical, inflammatory, and oxidative stress parameters in rats fed with high-fat diet (HFD). After feeding with HFD for 12 weeks, the animals were supplemented with VCO for 30 days. HFD+VCO group increased in diet intake, weight gain, low-density lipoprotein cholesterol level, and aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels. These findings were accompanied by increased in hepatic lipid profile and fat deposition in the liver. Adipocyte hypertrophy was observed in the HFD+VCO group, which was associated with elevated expression of tumor necrosis factor alpha (TNF-α) in adipose tissue. These results revealed that VCO associated with HFD induced important metabolic alterations, adipose inflammation, and hepatic lipid accumulation in rats.

Lauric acid induce cell death in colon cancer cells mediated by the epidermal growth factor receptor downregulation: An in silico and in vitro study

Coconut oil (CO) is enriched with medium chain saturated fatty acids like lauric acid (LA), capric acid and caprylic acid, which are known to have several health benefits. LA, the predominant fatty acid in CO, is reported to possess anticancer activity mediated through oxidative stress-induced apoptosis; however, there is no clear information on its cellular signalling mechanism. The present study screened the anticancer potential of various fatty acids present in CO (capric acid, caprylic acid and LA) using in silico tools such as CDOCKER in Accelrys Discovery Studio by targeting proteins like epidermal growth factor receptor (EGFR), cyclin-dependent kinase and thymidine synthase (TS). The results were further confirmed using cell culture-based studies and quantitative PCR. Among the tested compounds, LA was found to be the most active and showed a higher affinity towards EGFR and TS. Corroborating with these results, LA-induced dose-dependent cytotoxicity towards HCT-15 (human colon cancer), HepG2 (human hepatocellular carcinoma) and Raw 264.7 (murine macrophages) cells exhibiting morphological characteristics of apoptosis. Further, in HCT-15 cells exposed to LA (30 and 50 µg/mL), the expression of EGFR was found to be downregulated by 1.33- and 1.58-fold. The study thus concludes that the anticancer activity of LA may be partially mediated by the downregulation of EGFR signalling and consequent reduction in cell viability through apoptosis. Since EGFR signalling is crucial in cancer cell survival and is a prime target in drug development, the present study has pharmacological significance.

Non-polar lipid carbonyls of thermally oxidized coconut oil induce hepatotoxicity mediated by redox imbalance

Thermal oxidation products of edible oils including aldehydes, peroxides and polymerized triglycerides formed during the cooking process are increasingly debated as contributory to chronic degenerative diseases. Depending on the oil used for cooking, the source of fatty acids and its oxidation products may vary and would have a differential influence on the physiological process. Coconut oil (CO) is a medium chain triglyceride-rich edible oil used in South India and other Asia Pacific countries for cooking purposes. The present study evaluated the biological effects of thermally oxidized coconut oil (TCO) as well as its non- polar hexane (TCOH) and polar methanol (TCO-M) sub-fractions in male Wistar rats. Results showed an increase in the thiobarbituric acid reactive substances (TBARs) and conjugated diene levels in TCO, which was extracted to TCOH fraction. The animals consumed TCO and its hexane and methanol fractions had a considerable increase in weight gain. However, serum and hepatic triglycerides were increased only in animals with TCO and TCOH administration. In these animals, the hepatic redox balance was disturbed, with a reduction in GSH and a concomitant increase in thiobarbituric acid reactive substances (TBARs). Increased incidence of microvesicles in hepatic histological observations also supported this assumption. Together, the study shows that TCO consumption is unhealthy, where the nonpolar compounds generated during thermal oxidation may be involved in the toxic insults.

Comparative Effect of Dietary Soybean Oil, Fish Oil, and Coconut Oil on Performance, Egg Quality and Some Blood Parameters in Laying Hens

Two hundred and sixteen 28-wk-old Hy-line laying hens were randomly distributed to three dietary treatments and fed 1of 3 diets containing 8% soybean oil, fish oil, or coconut oil from 28 to 47 wk of age to investigate comparative effect of dietary soybean oil, fish oil, and coconut oil on the performance, egg quality and blood malondialdehyde (MDA), aspartate transaminase (AST) and uric acid (UA). Hens fed fish oil showed poor performance compared with soybean oil or coconut oil, and especially egg weight throughout the trial was significantly and consistently decreased (P < 0.05) due to dietary fish oil. Unexpectedly, shell reflectivity throughout the majority of the trial was consistently and significantly higher (P < 0.05) when hens fed fish oil than that when fed soybean oil or coconut oil. Dietary treatments affected (P < 0.05) shell shape at 4 of 8 time points tested. Average shell shape in fish oil treatment was higher (P < 0.05) than that of coconut oil group. Albumen height, Haugh unit and yolk color were influenced by dietary treatments only at 1 or 2 time points. However, average albumen height and Haugh unit in fish oil treatment were higher (P < 0.05) than that of soybean oil or coconut oil treatments and average yolk color in coconut oil treatment was higher (P < 0.05) than that of soybean oil group. Serum MDA, AST and UA concentrations were increased (P < 0.05) by fish oil during the majority of the first 2 mo of the trial. These data suggested that the inclusion of fish oil into feed may reduce the performance of laying hens, especially the egg weight, decrease the intensity of egg brown color and increase blood MDA, AST and UA levels compared with soybean oil or coconut oil. As a result, hens fed fish oil may lay smaller, longer and lighter-brown eggs whereas those fed coconut oil produce blunter and darker-brown eggs relative to soybean oil.

Beneficial role of virgin coconut oil supplementation against acute methotrexate chemotherapy-induced oxidative toxicity and inflammation in rats

Background

Methotrexate (MTX) is a commonly used antineoplastic and anti-rheumatoid agent whose efficacy is limited by marked organ toxicities associated with oxidative stress. The study investigated beneficial effect of virgin coconut oil (VCO) supplementation on MTX-induced oxidative stress and inflammation in rats.

Methods

Rats were divided into 4 groups (n = 6): Control, MTX (20 mg/kg bw), VCO (5%) + MTX and VCO (15%) + MTX. The pre-treatment with VCO for 14 days was followed by single intraperitoneal injection of MTX and the rats were sacrificed after 3 days. Serum activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), and levels of reduced glutathione (GSH) and malondialdehyde (MDA) were determined. Interleukin-6 (IL-6), C-reactive protein (CRP) and nitric oxide (NO) levels were also evaluated.

Results

MTX induced a distinct diminution in serum activities of oxidative stress markers (SOD, CAT, GPx and GSH), while lipid peroxidation considerably increased demonstrated by MDA level. Similarly, levels of IL-6, CRP and NO increased prominently in MTX control rats. The VCO supplementation markedly enhanced resistance to the MTX-induced biochemical alterations in rats.

Conclusion

VCO can be a useful adjuvant natural product in MTX chemotherapy by reducing oxidative stress and pro-inflammatory responses.

Coconut phytocompounds inhibits polyol pathway enzymes: Implication in prevention of microvascular diabetic complications

Coconut oil (CO), the primary choice of cooking purposes in the south Asian countries, is rich in medium chain saturated fatty acids, especially lauric acid (50-52%). The oil has high medicinal use in Ayurvedic system and known to contain polyphenolic antioxidants. Studies have reported that CO improves insulin sensitivity and shows hypoglycemic effect. However, there is no information regarding its effect on chronic diabetic complications including retinopathy and nephropathy is available. The secondary diabetic complications are mediated by the activation of polyol pathway, where aldose reductase (AR) plays crucial role. In this study, in silico analysis has been used to screen the effect of CO as well as its constituents, MCFAs and phenolic compounds, for targeting the molecules in polyol pathway. The study revealed that lauric acid (LA) interacts with AR and DPP-IV of polyol pathway and inhibits the activity of these enzymes. Validation studies using animal models confirmed the inhibition of AR and SDH in wistar rats. Further, the LA dose dependently reduced the expression of AR in HCT-15 cells. Together, the study suggests the possible role of CO, particularly LA in reducing secondary diabetic complications.

Coconut Products Improve Signs of Diet-Induced Metabolic Syndrome in Rats

Increasing prevalence of obesity and metabolic syndrome warrants identification of potential therapeutic options for intervention. This study tested commercially available Virgin Coconut Oil and Coconut Nourish, as coconuts are rich sources of lauric and myristic acids. Male Wistar rats were fed either corn starch diet (C); high-carbohydrate, high-fat diet (H); high-carbohydrate, high-virgin coconut oil diet (HV); or high-carbohydrate, high-coconut Nourish diet (HN) for 16 weeks. Metabolic, liver, and cardiovascular health parameters were measured during and at the end of the study. Virgin coconut oil lowered body weight (C 386±8g, H 516±13g, HV 459±10g), blood glucose concentrations (C 4.2±0.1 mmol/L, H 5.4±0.2 mmol/L, HV 4.6±0.2 mmol/L), systolic blood pressure (C 127±5mmHg, H 149±4mmHg, HV 133±3mmHg,) and diastolic stiffness (C 25.0±1.7, H 31.4±1.2, HV 25.2±2.3,) with improved structure and function of the heart and liver. Coconut Nourish increased total body lean mass (C 255±10g, H 270±16g, HN 303±15g) and lowered plasma total cholesterol concentrations (C 1.6±0.2 mmol/L, H 1.7±0.1 mmol/L, HN 1.0±0.0 mmol/L), systolic blood pressure (C 127±5mmHg, H 149±4mmHg, HN 130±3mmHg) and diastolic stiffness (C 25.0±1.7, H 31.4±1.2, HN 26.5±1.0), improved structure and function of the heart and liver but increased plasma concentrations of triglycerides (C 0.3±0.1 mmol/L, H 1.1±0.4 mmol/L, HN 1.8±0.2 mmol/L) and non-esterified fatty acids (C 1.2±0.3 mmol/L, H 3.3±0.8 mmol/L, HN 5.6±0.4 mmol/L). Thus, the fiber and protein in coconut Nourish and the medium-chain saturated fatty acids in virgin coconut oil may improve cardiovascular and liver complications in obesity.