Carotenoids in the treatment of diabetes mellitus and its complications: A mechanistic review

Effects of carotenoid supplementation on glycemic control: a systematic review and meta-analysis of randomized clinical trials

OBJECTIVES

We conducted a systematic review and meta-analysis to assess the effects of carotenoid supplementation on glycemic indices, and the certainty of evidence.

METHODS

A systematic literature search in PubMed, SCOPUS, ISI-Web of Science, and Cochrane Library was conducted from inception up to Jun 17, 2024. Randomized controlled trials (RCTs) investigating the effect of carotenoid supplementation on circulating glycemic parameters were included. Records were excluded when studies reported the effect of co-interventions with other nutrients, did not provide mean differences (MDs) and standard deviations (SD) for outcomes, or administered whole food rather than supplements of carotenoids. Summary mean differences (MDs) and 95% CI between intervention and control groups were estimated using a random-effects model. The risk of bias of the included studies was assessed using the Risk of Bias 2.0 (RoB 2.0) tool.

RESULTS

Overall, 36 publications with 45 estimated effect sizes were included in the meta-analyses. The overall findings showed an improvement in fasting blood glucose (FBG) (MD = -4.54 mg/dl; 95% CI: -5.9, -3.2; n = 45), and hemoglobin A1C (HbA1C) (MD = -0.25% (95% CI: -0.4, -0.11; n = 22) in the intervention group in comparison with the control group. Moreover, in individuals with type 2 diabetes (T2D), interventions with astaxanthin and fucoxanthin led to a reduction in FBG by 4.36 mg/dl (95% CI: -6.13, -2.6; n = 10). The findings also showed that the intervention with crocin reduced FBG levels by 13.5 mg/dl (95% CI: -15.5, -7.8; n = 5), and HbA1C by 0.55% (95% CI: -0.77, -0.34; n = 5) in individuals with T2D. However, the certainty of evidence was very low.

CONCLUSION

Carotenoid's supplementation improved glycemic parameters especially in people with T2D. However. the certainty of evidence was very low, mainly due to small sample size, and indirectness. Therefore, no specific recommendations can be provided at present and well-designed RCTs are required. REGISTRY URL: https://www.crd.york.ac.uk/PROSPERO/ REGISTRY NUMBER: CRD42021285084 REGISTRY AND REGISTRY NUMBER FOR SYSTEMATIC REVIEWS OR META-ANALYSES: PROSPERO ID: CRD42021285084.

Unveiling astaxanthin: biotechnological advances, delivery systems and versatile applications in nutraceuticals and cosmetics

Astaxanthin (ASX), "king of carotenoids", is a xanthophyll carotenoid that is characterized by a distinct reddish-orange hue, procured from diverse sources including plants, microalgae, fungi, yeast, and lichens. It exhibits potent antioxidant and anti-ageing properties and has been demonstrated to mitigate ultraviolet-induced cellular and DNA damage, enhance immune system function, and improve cardiovascular diseases. Despite its broad utilization across nutraceutical, cosmetic, aquaculture, and pharmaceutical sectors, the large-scale production and application of ASX are constrained by the limited availability of natural sources, low production yields and stringent production requirements. This review provides a comprehensive analysis of ASX applications, emphasizing its dual roles in cosmetic and nutraceutical fields. It integrates insights into the qualitative differences of ASX from various natural sources and assesses biosynthetic pathways across organisms. Advanced biotechnological strategies for industrial-scale production are explored alongside innovative delivery systems, such as emulsions, films, microcapsules, nanoliposomes, and nanoparticles, designed to enhance ASX's bioavailability and functional efficacy. By unifying perspectives on its nutraceutical and cosmetic applications, this review highlights the challenges and advancements in formulation and commercialization. Prospective research directions for optimizing ASX's production and applications are also discussed, providing a roadmap for its future development.

The positive implication of natural antioxidants on oxidative stress-mediated diabetes mellitus complications

The complementary intervention to modulate diabetes mellitus (DM) metabolism has recently brought the global attention, since DM has become among the global burden diseases. Where, several related pathways elevate the production of superoxide in consequences. For example, the flux of glycation-derived end products (AGEs) could lead to the deactivation of insulin signaling pathways. In that context, many vitamins and phytochemicals in natural sources have high antioxidant impacts that reduce oxidative stress and cell damages. These chemicals could be applied as bioactive antidiabetic agents. Their mode of actions could be from regulating the intracellular reactive oxygen species (ROS) which cause several pro-inflammatory pathways related to the oxidative stress (OS) and DM. Besides, they have a great potential to control the epigenetic mutations and hyperglycemia and help in back the blood glucose to the normal level. Therefore, the current review addresses the important role of natural functional antioxidants in DM management and its association with its OS complications.

Consumption of carotenoid-rich Momordica cochinchinensis (Gac) aril improves glycemic control in type 2 diabetic mice partially through taste receptor type 1 mediated glucagon-like peptide 1 secretion

Incretin-based therapies are widely used to improve glycemic control and β cell dysfunction in the treatment of type 2 diabetes. Momordica cochinchinensis (Gac fruit), a nutritious melon cultivated in many regions, has underexplored health benefits, particular its edible aril. This study comprehensively investigates the stimulatory effect of Gac aril on glucagon-like peptide 1 (GLP-1) secretion, identifies the responsible active constituents, and explores the underlying mechanisms related to its anti-diabetic effects. GLP-1-secreting STC-1 intestinal L cells were used to assess bioactivity and molecular mechanisms. Additionally, the in vivo anti-diabetic effects of Gac aril consumption were evaluated using type 2 diabetic mice induced by a high fat diet and streptozotocin injection, with or without GLP-1 receptor expression. The results demonstrated that Gac pulp and aril stimulated GLP-1 secretion, while Gac seeds did not. β-Carotene, a major constituent of Gac aril, was identified as the key mediator of GLP-1 secretion via sweet taste receptor-mediated signaling in STC-1 cells. Dietary intake of Gac aril significantly improved fasting blood glucose, glucose tolerance, insulin sensitivity, β-cell function, and hemoglobin A1c in type 2 diabetic mice. GLP-1 levels increased 2-fold, and decreased levels of ghrelin and adiponectin were restored. The anti-diabetic effects were partially diminished in GLP-1 receptor knockout mice, suggesting Gac aril's effects are mediated, in part, through GLP-1. In conclusion, Gac aril consumption may provide health benefits for managing type 2 diabetes, partially by enhancing endogenous GLP-1 levels.

Application of Integrated Optical Density in Evaluating Insulin Expression in the Endocrine Pancreas During Chronic Ethanol Exposure and β-Carotene Supplementation: A Novel Approach Utilizing Artificial Intelligence

BACKGROUND

β-carotene is an essential antioxidant, providing protection against type 2 diabetes mellitus, cardiovascular illnesses, obesity, and metabolic syndrome. This study investigates the impact of β-carotene on biochemical parameters and pancreatic insulin expression in mice exposed to ethanol.

METHODS

Thirty-six C57BL/6 mice (Mus musculus) were divided into six groups: 1. C (control), 2. LA (3% alcohol dose), 3. MA (7% alcohol dose), 4. B (0.52 mg/kg body weight/day β-carotene), 5. LA+B (3% alcohol dose + 0.52 mg/kg body weight/day β-carotene), and 6. MA+B (7% alcohol dose plus 0.52 mg/kg body weight/day β-carotene). After 28 days, the animals were euthanized for serum and pancreatic tissue collection. Biochemical analysis and pancreatic insulin expression were performed. One-way ANOVA was used.

RESULTS

The B, LA+B, and MA+B groups improved insulin levels and decreased HOMA-β versus the C group, with the LA+B and MA+B groups also showing lower ADH and ALDH levels than their nonsupplemented counterparts (p < 0.05). The B, LA+B, and MA+B groups showed a greater β-cell mass area compared to the unsupplemented groups. Additionally, the LA+B and MA+B groups demonstrated significantly increased β-cell area and integrated optical density compared to the LA and MA groups, respectively (p < 0.001).

CONCLUSIONS

In mice, β-cell loss led to increased glucose release due to decreased insulin levels. β-carotene appeared to mitigate ethanol's impact on these cells, resulting in reduced insulin degradation when integrated optical density was used. These findings suggest that antioxidant supplementation may be beneficial in treating ethanol-induced type 2 diabetes in animal models.

Bixin Combined with Metformin Ameliorates Insulin Resistance and Antioxidant Defenses in Obese Mice

Bixin (C25H30O4; 394.51 g/mol) is the main apocarotenoid found in annatto seeds. It has a 25-carbon open chain structure with a methyl ester group and carboxylic acid. Bixin increases the expression of antioxidant enzymes, which may be interesting for counteracting oxidative stress. This study investigated whether bixin-rich annatto extract combined with metformin was able to improve the disturbances observed in high-fat diet (HFD)-induced obesity in mice, with an emphasis on markers of oxidative damage and antioxidant defenses. HFD-fed mice were treated for 8 weeks with metformin (50 mg/kg) plus bixin-rich annatto extract (5.5 and 11 mg/kg). This study assessed glucose tolerance, insulin sensitivity, lipid profile and paraoxonase 1 (PON-1) activity in plasma, fluorescent AGEs (advanced glycation end products), TBARSs (thiobarbituric acid-reactive substances), and the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in the liver and kidneys. Treatment with bixin plus metformin decreased body weight gain, improved insulin sensitivity, and decreased AGEs and TBARSs in the plasma, liver, and kidneys. Bixin plus metformin increased the activities of PON-1, SOD, CAT, and GSH-Px. Bixin combined with metformin improved the endogenous antioxidant defenses in the obese mice, showing that this combined therapy may have the potential to contrast the metabolic complications resulting from oxidative stress.

Underutilized plants increase biodiversity, improve food and nutrition security, reduce malnutrition, and enhance human health and well-being. Let's put them back on the plate!

The global food system depends on a limited number of plant species. Plants with unsatisfactory nutritional value are overproduced, whereas the wide variety of nutrient-rich plant species used in earlier times remains neglected. Basing our diet on a few crops has wide-ranging negative consequences on nutrition and food security. Although still under-researched, underutilized plants are slowly starting to receive increased recognition. These plants have superior nutritional content and immense potential to contribute to food and nutrition security and increased sustainability. This narrative review provides evidence to encourage the promotion, domestication, and commercialization of underutilized plants. The anti-inflammatory, antidiabetic, and anticancer effects of some of underutilized plants are presented in this review. The outstanding ability of forgotten plants to increase food and nutrition security, boost dietary diversity, reduce malnutrition, and enhance human health and well-being is demonstrated. The main barriers and obstacles to reintroducing underutilized foods are reviewed and recommendations for overcoming nutrition and dietary-related challenges for re-establishing underutilized plants into the global food system are presented. The expansion of underutilized plants for human use is of paramount importance. The exceptional nutritional properties, bioactive potential, and proven health benefits of underutilized plants indicate that increased promotion, domestication, and commercialization of these plants should be strongly supported. Besides health benefits, marginalized plants have the potential to enhance human well-being and improve people's lives in many ways, retain biodiversity, and develop local economies. Therefore, underutilized plants should be used in the broader context of well-balanced and healthy diets.

True or false? Alzheimer's disease is type 3 diabetes: Evidences from bench to bedside

Globally, Alzheimer's disease (AD) is the most widespread chronic neurodegenerative disorder, leading to cognitive impairment, such as aphasia and agnosia, as well as mental symptoms, like behavioral abnormalities, that place a heavy psychological and financial burden on the families of the afflicted. Unfortunately, no particular medications exist to treat AD, as the current treatments only impede its progression.The link between AD and type 2 diabetes (T2D) has been increasingly revealed by research; the danger of developing both AD and T2D rises exponentially with age, with T2D being especially prone to AD. This has propelled researchers to investigate the mechanism(s) underlying this connection. A critical review of the relationship between insulin resistance, Aβ, oxidative stress, mitochondrial hypothesis, abnormal phosphorylation of Tau protein, inflammatory response, high blood glucose levels, neurotransmitters and signaling pathways, vascular issues in AD and diabetes, and the similarities between the two diseases, is presented in this review. Grasping the essential mechanisms behind this detrimental interaction may offer chances to devise successful therapeutic strategies.

Biomarkers of food intake and their relevance to metabolic syndrome

Metabolic syndrome (MetS) constitutes a prevalent risk factor associated with non communicable diseases such as cardiovascular disease and type 2 diabetes. A major factor impacting the etiology of MetS is diet. Dietary patterns and several individual food constituents have been related to the risk of developing MetS or have been proposed as adjuvant treatment. However, traditional methods of dietary assessment such as 24 h recalls rely greatly on intensive user-interaction and are subject to bias. Hence, more objective methods are required for unbiased dietary assessment and efficient prevention. While it is accepted that some dietary-derived constituents in blood plasma are indicators for certain dietary patterns, these may be too unstable (such as vitamin C as a marker for fruits/vegetables) or too broad (e.g. polyphenols for plant-based diets) or reflect too short-term intake only to allow for strong associations with prolonged intake of individual food groups. In the present manuscript, commonly employed biomarkers of intake including those related to specific food items (e.g. genistein for soybean or astaxanthin and EPA for fish intake) and novel emerging ones (e.g. stable isotopes for meat intake or microRNA for plant foods) are emphasized and their suitability as biomarker for food intake discussed. Promising alternatives to plasma measures (e.g. ethyl glucuronide in hair for ethanol intake) are also emphasized. As many biomarkers (i.e. secondary plant metabolites) are not limited to dietary assessment but are also capable of regulating e.g. anti-inflammatory and antioxidant pathways, special attention will be given to biomarkers presenting a double function to assess both dietary patterns and MetS risk.

Astaxanthin could regulate the gut-kidney axis to mitigate kidney injury in high-fat diet/streptozotocin-induced diabetic mice

Accumulating evidences have shown the beneficial effects of astaxanthin (AST) supplementation on metabolic diseases prevention and treatment. The goal of present study was to reveal the favorable interactions among AST supplementation, gut microbiota, and kidneys in vivo, so as to attenuate kidney impairment in diabetic mice. Twenty C57BL/6J mice were assigned to a normal control group and a diabetic model group induced by a high-fat diet plus low-dose streptozotocin, and then the diabetic mice were fed with a high-fat diet without or with AST [0.01% (AST_a) or 0.02% (AST_b)] for 12 weeks. When compared to the diabetes kidney disease (DKD) group, AST supplementation delayed the renal pathological progression, reduced fasting blood glucose (AST_b: 1.53-fold, p<0.05), repressed levels of lipopolysaccharide (LPS; AST_a: 1.24-fold, p=0.008; AST_b: 1.43-fold, p<0.001) and TMAO (AST_a: 1.51-fold, p=0.001; AST_b: 1.40-fold, p=0.003), inhibited IL-6 (AST_a: 1.40-fold, p=0.004; AST_b: 1.57-fold, p=0.001) and reactive oxygen species (ROS; AST_a: 1.30-fold, p=0.004; AST_b: 1.53-fold, p<0.001), as well as regulated the Sirt1/PGC-1α/NFκB p65 signaling pathway. Moreover, the results of 16S rRNA gene-based Illumina deep sequencing in each group revealed that dietary AST supplementation also favorably modulated the gut microbiota compared with the DKD group, as evidenced by the inhibition of the harmful bacteria Clostridium_sensu_stricto_1, Romboutsia, and Coriobacteriaceae_UCG-002, and the enhancement of the probiotics such as Lachnospiraceae_NK4A136_group, Roseburia, and Ruminococcaceae. Taken together, dietary AST supplementation could protect kidneys against inflammation and oxidative stress by adjusting the gut-kidney axis in diabetic mice.

Lycopene in Combination with Insulin Triggers Antioxidant Defenses and Increases the Expression of Components That Detoxify Advanced Glycation Products in Kidneys of Diabetic Rats

BACKGROUND

Biochemical events provoked by oxidative stress and advanced glycation may be inhibited by combining natural bioactives with classic therapeutic agents, which arise as strategies to mitigate diabetic complications. The aim of this study was to investigate whether lycopene combined with a reduced insulin dose is able to control glycemia and to oppose glycoxidative stress in kidneys of diabetic rats.

METHODS

Streptozotocin-induced diabetic rats were treated with 45 mg/kg lycopene + 1 U/day insulin for 30 days. The study assessed glycemia, insulin sensitivity, lipid profile and paraoxonase 1 (PON-1) activity in plasma. Superoxide dismutase (SOD) and catalase (CAT) activities and the protein levels of advanced glycation end-product receptor 1 (AGE-R1) and glyoxalase-1 (GLO-1) in the kidneys were also investigated.

RESULTS

An effective glycemic control was achieved with lycopene plus insulin, which may be attributed to improvements in insulin sensitivity. The combined therapy decreased the dyslipidemia and increased the PON-1 activity. In the kidneys, lycopene plus insulin increased the activities of SOD and CAT and the levels of AGE-R1 and GLO-1, which may be contributing to the antialbuminuric effect.

CONCLUSIONS

These findings demonstrate that lycopene may aggregate favorable effects to insulin against diabetic complications resulting from glycoxidative stress.

Characterization of the gut bacterial and viral microbiota in latent autoimmune diabetes in adults

Latent autoimmune diabetes in adults (LADA) is a heterogeneous disease characterized by autoantibodies against insulin producing pancreatic beta cells and initial lack of need for insulin treatment. The aim of the present study was to investigate if individuals with LADA have an altered gut microbiota relative to non-diabetic control subjects, individuals with type 1 diabetes (T1D), and individuals with type 2 diabetes (T2D). Bacterial community profiling was performed with primers targeting the variable region 4 of the 16S rRNA gene and sequenced. Amplicon sequence variants (ASVs) were generated with DADA2 and annotated to the SILVA database. The gut virome was sequenced, using a viral particle enrichment and metagenomics approach, assembled, and quantified to describe the composition of the viral community. Comparison of the bacterial alpha- and beta-diversity measures revealed that the gut bacteriome of individuals with LADA resembled that of individuals with T2D. Yet, specific genera were found to differ in abundance in individuals with LADA compared with T1D and T2D, indicating that LADA has unique taxonomical features. The virome composition reflected the stability of the most dominant order Caudovirales and the families Siphoviridae, Podoviridae, and Inoviridae, and the dominant family Microviridae. Further studies are needed to confirm these findings.

The role of carotenoids in bone health-A narrative review

Osteoporosis constitutes a serious challenge for public health. Dietary patterns belong to important, modifiable risk factors of this disease. Therefore, what and in what quantities we consume on a daily basis are extremely relevant. It is commonly known that bone health is positively affected by vitamins (e.g., vitamin D and vitamin K) as well as mineral components (e.g., calcium and magnesium). However, the human diet consists of many other groups of compounds that exhibit a potential antiosteoporotic and supporting bone-building effect. These dietary components include carotenoids. This paper presents a broad review of studies on the influence of particular carotenoids (β-carotene, lutein, zeaxanthin, β-cryptoxanthin, and lycopene) on bones. The paper discusses up-to-date in vitro experiments and research on animal models and presents how the results translate into clinical effect in humans.

'Oxidative stress'-A new target in the management of diabetes mellitus

Diabetes mellitus (DM) is a chronic condition that poses a mammoth challenge for the healthcare system in developing as well as developed nations. Diabetes mellitus is associated with damage to the vasculature which leads to microvascular and macrovascular complications. Oxidative stress is a consequence of glucotoxicity and lipotoxicity, which are associated with diabetes. Glucotoxicity and lipotoxicity play a part in the pathogenesis of β-cell dysfunction. The hyperglycemic state in DM leads to oxidative stress which further hampers insulin secretion. In diabetes, the biological antioxidants also get depleted along with a reduction in glutathione (GSH), an increase in the oxidized glutathione (GSSG)/GSH ratio, and a depletion of non-enzymatic antioxidants. This results in the formation of a viscous circle of hyperglycemia leading to increased oxidative stress that further hampers insulin secretion which in turn results in hyperglycemia. Antioxidants are efficacious in reducing diabetic complications. The antioxidants produced biologically fall short, hence external supplements are required. In this review, the authors have discussed the relationship between oxidative stress in DM and the advantages of antioxidant supplements in controlling blood glucose levels and also in deaccelerating the complications related to DM.

Dietary carotenoids to improve hypertension

Hypertension is one of the major risk factors for cardiovascular diseases and the main reason for premature death in older adults. Although antihypertensive medications have been used frequently, hypertension prevalence has increased in the last decade. Lifestyle improvement is a cornerstone of hypertension prevention and control. High dietary consumptions of fruits and vegetables are linked to reduced risks of high blood pressure. Carotenoids are natural tetraterpene pigments produced by bacteria, fungi, algae, some animals, and various plants. Because of their high pharmacological potential and safety, they have been mentioned as unique therapeutic agents for a diverse range of diseases. Carotenoids modulate high blood pressure. They also have several additional benefits for the cardiovascular system, including antioxidative, anti-inflammatory, anti-atherogenic, and antiplatelet effects. They improve endothelial function and metabolic profile, as well. In the present article, we reviewed the literature data regarding carotenoids' influence on hypertension in both preclinical and clinical studies. Furthermore, we reviewed the underlying mechanisms associated with antihypertensive properties derived from in vitro and in vivo studies. Suppressing reactive oxygen species (ROS) production, Inhibiting angiotensin-II, endothelin-1, and oxidized low-density lipoprotein; and also nitric oxide enhancement are some of the mechanisms by which they lower blood pressure. The present article indicated that astaxanthine, β-carotene, bixin, capsanthin, lutein, crocin, and lycopene have antihypertensive properties. Having significant antioxidant properties, they can decrease high blood pressure and concomitant comorbidities.

Carotenoids from Starfish Patiria pectinifera: Therapeutic Activity in Models of Inflammatory Diseases

The carotenoids mixture (MC) isolated from the starfish Patiria. pectinifera contains more than 50% astaxanthin, 4-6% each zeaxanthine and lutein, and less pharmacologically active components such as free fatty acids and their glycerides. Astaxanthin, the major component of MC, belongs to the xanthophyll class of carotenoids, and is well known for its antioxidant properties. In this work, in vitro and in vivo studies on the biological activity of MC were carried out. The complex was shown to exhibit anti-inflammatory, anti-allergic and cancer-preventive activity, without any toxicity at a dose of 500 mg/kg. MC effectively improves the clinical picture of the disease progressing, as well as normalizing the cytokine profile and the antioxidant defense system in the in vivo animal models of inflammatory diseases, namely: skin carcinogenesis, allergic contact dermatitis (ACD) and systemic inflammation (SI). In the skin carcinogenesis induced by 7,12-dimethylbenzanthracene, the incidence of papillomas was decreased 1.5 times; 1% MC ointment form in allergic contact dermatitis showed an 80% reduced severity of pathomorphological skin manifestations. Obtained results show that MC from starfish P. pectinifera is an effective remedy for the treatment and prevention of inflammatory processes.

Fruits as nutraceuticals: A review of the main fruits included in nutraceutical patents

Fruits have relevant usefulness in the elaboration of nutraceutical compositions and, as it is considered a "natural medicine", its market has been growing exponentially each year. Fruits, in general, contain a large source of phytochemicals, carbohydrates, vitamins, amino acids, peptides and antioxidants that are of interest to be prepared as nutraceuticals. The biological properties of its nutraceuticals can range from antioxidant, antidiabetic, antihypertensive, anti-Alzheimer, antiproliferative, antimicrobial, antibacterial, anti-inflammatory, among others. Furthermore, the need for innovative extraction methods and products reveals the importance of developing new nutraceutical compositions. This review was developed by searching patents of nutraceuticals from January 2015 until January 2022 in Espacenet, the search database of the European Patent Office (EPO). Of 215 patents related to nutraceuticals, 43% (92 patents) were including fruits, mainly berries. A great number of patents were focused on the treatment of metabolic diseases, representing 45% of the total patents. The principal patent applicant was the United States of America (US), with 52%. The patents were applied by researchers, industries, research centers and institutes. It is important to highlight that from 92 fruit nutraceutical patent applications reviewed, 13 already have their products available on the market.

Preparation and in vitro characterization studies of astaxanthin-loaded nanostructured lipid carriers with antioxidant properties

The purpose of this study was to evaluate the astaxanthin-loaded nanostructured lipid carriers (ASX-NLC) prepared using a high-pressure homogenization transport system for local application of astaxanthin. Dynamic light scattering (DLS) and X-ray diffraction (XRD) were used to study the effect of microencapsulation on the properties of ASX-NLC. The mean size of ASX-NLC was about 108.43 ± 0.26 nm and PdI was 0.176 ± 0.002. The ASX-NLC had high encapsulation efficiency which was 95.69 ± 0.13%. Good light stability and temperature stability were shown at the ASX-NLC, indicating that the preparation process was feasible. The 2,2-diphenyl-1-pyridylohydrazinyl (DPPH) scavenging test showed that ASX-NLC could still play an antioxidant role. In vitro release studies showed that compared with an astaxanthin ethanol solution, an ASX-NLC could maintain astaxanthin release more effectively. In vitro permeation studies showed that ASX-NLC could increase astaxanthin retention in the skin. In conclusion, ASX-NLC could significantly enhance astaxanthin accumulation during dermal applications. The research results have important reference significance for local skin applications and provide a basis for the development of nanostructured lipid carriers. ASX-NLC might be suitable carriers for the local application of astaxanthin.

Rationale and design of the linking education, produce provision, and community referrals to improve diabetes care (LINK) study

BACKGROUND

Individuals with type 2 diabetes (T2D) experiencing food insecurity may have other non-medical, health-related social needs (e.g., transportation, housing instability) that decrease their ability to attain T2D control and impact other health outcomes.

METHODS

A pragmatic randomized controlled trial (pRCT) to test the effect of produce provision, diabetes and culinary skills training and education, and social needs screening, navigation, and resolution, on hemoglobin A1c (A1c) levels in individuals with T2D (A1c ≥7.5%) experiencing food insecurity; a cost-effectiveness evaluation of the interventions that comprise the pRCT; and a process evaluation to understand the contextual factors that impact the uptake, effectiveness, and sustainability of the interventions.

SETTING

Ambulatory care clinics (e.g., family medicine, general internal medicine, endocrinology) affiliated with an academic medical center in an urban environment in the Midwest.

DESIGN

2 × 2 factorial design.

INTERVENTIONS

Cooking Matters for Diabetes is a 6-week diabetes and culinary education intervention. The Health Impact Ohio Central Ohio Pathways Hub intervention is a community health worker model designed to evaluate and address participants' social needs. All participants will receive referral to the Mid-Ohio Farmacy to provide weekly access to fresh produce.

OUTCOMES

Primary outcome of the pRCT is change in A1c at 3 months; secondary outcomes include A1c at 6 months, and diabetes self-efficacy, food insecurity, and diet quality at 3 and 6 months.

DISCUSSION

Food insecurity, unmet social needs, diabetes education and self-efficacy are critical issues that must be addressed to improve T2D treatment, care, and health equity.

CLINICALTRIALS

gov: NCT05472441.

Astaxanthin improves fatty acid dysregulation in diabetes by controlling the AMPK-SIRT1 pathway

Due to the rising prevalence of metabolic disorders, including type 2 diabetes (T2DM), new prevention and treatment strategies are needed. The aim was to examine the effect of astaxanthin (AST) on the major regulatory metabolism pathway SIRT-MAPK and fatty acid (FA) profile of plasma in patients with T2DM. This clinical trial included 68 T2DM patients randomly assigned to receive 10 mg/day of oral AST (n = 34) or placebo (n = 33) for 12 weeks. The expression level of SIRT1, AMPK activity, and the level of fatty acids in the serum were examined. The results showed that AST could modify the serum levels of saturated fatty acids (SFA) and polyunsaturated fatty acids (PUFA), particularly that of Arachidonic acid, from 11.31±0.35 to 8.52±0.72 %. Also, AST increased the expression and activity levels of SIRT1 and AMPK, respectively. Pearson analysis also revealed a significant association between AMPK activity and Linoleic acid serum (LA) levels (~ -0.604, p~0.013). AST can modify the FA profile of plasma by inducing metabolizing cells to uptake them. Also, it can activate the SIRT-AMPK pathway related to metabolism regulation. See also Figure 1(Fig. 1).

In vivo antidiabetic effects of phenolic compounds of spinach, mustard, and cabbage leaves in mice

Leafy vegetables are considered to have health-promoting potentials, mainly attributed to bioactive phenolic compounds. The antidiabetic effects of spinach, mustard, and cabbage were studied by feeding their phenolic-rich aqueous extracts to alloxan-induced diabetic mice. The antioxidant, biochemical, histopathological, and hematological indices of the control, diabetic, and treated mice were studied. Phenolic compounds present in the extracts were identified and quantified using HPLC-DAD. Results showed ten, nineteen, and eleven phenolic compounds in spinach, mustard, and cabbage leave aqueous extracts, respectively. The body weight, tissue total glutathione (GSH) contents, fasting blood sugar, liver function tests, renal function tests, and lipid profile of the mice were affected by diabetes and were significantly improved by the extract treatments. Likewise, hematological indices and tissues histological studies also showed recovery from diabetic stress in treated mice. The study's findings highlight that the selected leafy vegetables potentially mitigate diabetic complications. Among the studied vegetables, cabbage extract was comparatively more active in ameliorating diabetic stress.

Genetic Improvement to Obtain Specialized Haematococcus pluvialis Genotypes for the Production of Carotenoids, with Particular Reference to Astaxanthin

Nowadays, the search for natural substances with a high nutraceutical effect positively impact the world market. Among the most attractive macromolecules are antioxidants, capable of preventing the development of various pathologies. Astaxanthin (ASX) is antioxidant molecule produced by the microalga H. pluvialis as a response to different types of stress. Usually, astaxanthin production involves the first phase of accumulation of the biomass of H. pluvialis (green phase), which is then stressed to stimulate the biosynthesis and accumulation of ASX (red phase). In this study, the H. pluvialis wild-type strain was subjected to random mutagenesis by UV. Among the different mutant strains obtained, only two showed interesting bio-functional characteristics, such as a good growth rate. The results demonstrated that the HM1010 mutant not only has a higher growth trend than the WT mutant but accumulates and produces ASX even in the green phase. This innovative genotype would guarantee the continuous production of ASX, not linked to the two-step process and the uniqueness of the product obtained.

A Comprehensive Review of Health-Benefiting Components in Rapeseed Oil

Rapeseed oil is the third most consumed culinary oil in the world. It is well-known for its high content of unsaturated fatty acids, especially polyunsaturated fatty acids, which make it of great nutritional value. There is increasing evidence that a diet rich in unsaturated fatty acids offers health benefits. Although the consumption of rapeseed oil cuts across many areas around the world, the nutritional elements of rapeseed oil and the exact efficacy of the nutrients remain unclear. In this review, we systematically summarized the latest studies on functional rapeseed components to ascertain which component of canola oil contributes to its function. Apart from unsaturated fatty acids, there are nine functional components in rapeseed oil that contribute to its anti-microbial, anti-inflammatory, anti-obesity, anti-diabetic, anti-cancer, neuroprotective, and cardioprotective, among others. These nine functional components are vitamin E, flavonoids, squalene, carotenoids, glucoraphanin, indole-3-Carbinol, sterols, phospholipids, and ferulic acid, which themselves or their derivatives have health-benefiting properties. This review sheds light on the health-benefiting effects of rapeseed oil in the hope of further development of functional foods from rapeseed.

Effects of preharvest factors on antidiabetic potential of some foods and herbal plants

Diabetes is a metabolic disorder with no definite treatment, but it can be controlled by changing lifestyle and diet. Consumption of high-fiber and nutrient-rich foods including vegetables have been shown to reduce risks of obesity and Type II Diabetes Mellitus (T2DM). Also, many herbal plants have been associated with reduced risks of T2DM because of their composition of secondary metabolites. Antioxidant activities of some secondary metabolites have potent inhibitory effects against inflammation linked with insulin resistance and oxidative stress. More than 800 known medicinal plants are used to control diabetes and its relevant complications. However, variations in preharvest factors including plant genotype, growing medium properties, climatic factors, and management practices can influence plant growth and their accumulation of phytochemicals with health-promoting properties. However, the effects of these preharvest factors on the antidiabetic properties of plant secondary metabolites are neither explicit nor easily accessible in the literature. Therefore, this review aims to document recent studies that reported on under-exploited medicinal plants with antidiabetic properties. We reviewed several important preharvest factors that can potentially affect the synthesis of phytoconstituents which possess antidiabetic properties. This review will help identify gaps for future research in phytomedicine and functional foods.

Chemistry, Occurrence, Properties, Applications, and Encapsulation of Carotenoids-A Review

Carotenoids are natural lipophilic pigments and antioxidants that are present in many fruits and vegetables. The consumption of carotenoids is correlated with positive health effects and a decreased risk of several chronic diseases. Provitamin A carotenoids (β-carotene, α-carotene, γ-carotene, and β-cryptoxanthin) are essential for the development and maintenance of sight. β-carotene, α-carotene, zeaxanthin, β-cryptoxanthin, lutein, and lycopene have high antioxidant activity and promote free radical scavenging, which helps protect against chronic diseases. However, carotenoids are chemically unstable and prone to oxidation in the presence of light, heat, oxygen, acids, and metal ions. The use of carotenoids in the food industry is limited due to their poor solubility in water, bioavailability and quick release. Encapsulation techniques, such as microencapsulation, nanoencapsulation and supercritical encapsulation, are used to overcome these problems. The objective of this paper is to describe the characteristics and potential health benefits of carotenoids and advances in encapsulation techniques for protecting and enhancing their solubility or bioavailability.

Effects of supplementation of tropical fruit processing by-products on lipid profile, retinol levels and intestinal function in Wistar rats

Fruits agro-industrial by-products may have a great variety of bioactive compounds that promote health. Thus, the effects of supplementation with acerola, cashew and guava processing by-products for 28 days on retinol level, lipid profile and on some aspects related to intestinal function in rats were investigated. The animals supplemented with different fruit by-products presented similar weight gain, faecal pH values and intestinal epithelial structures; however, they showed higher moisture and Lactobacillus spp. and Bifidobacterium spp. counts in faeces compared to the control group. Supplementation with the cashew by-product decreased the blood glucose, acerola and guava by-products reduced serum lipid levels and all fruit by-products tested increased serum and hepatic retinol. The results indicated that acerola and guava by-products possess a potential hypolipidemic effect. The three fruit by-products increase the hepatic retinol deposition and the faecal populations of beneficial bacterial groups and modulated aspects of intestinal function. The findings of this study can contribute to sustainable fruticulture and support future clinical studies with the supplementation of by-products.

Circulating carotenoids are associated with favorable lipid and fatty acid profiles in an older population at high cardiovascular risk

Carotenoid intake has been reported to be associated with improved cardiovascular health, but there is little information on actual plasma concentrations of these compounds as biomarkers of cardiometabolic risk. The objective was to investigate the association between circulating plasma carotenoids and different cardiometabolic risk factors and the plasma fatty acid profile. This is a cross-sectional evaluation of baseline data conducted in a subcohort (106 women and 124 men) of an ongoing multi-factorial lifestyle trial for primary cardiovascular prevention. Plasma concentrations of carotenoids were quantified by liquid chromatography coupled to mass spectrometry. The associations between carotenoid concentrations and cardiometabolic risk factors were assessed using regression models adapted for interval-censored variables. Carotenoid concentrations were cross-sectionally inversely associated with serum triglyceride concentrations [-2.79 mg/dl (95% CI: -4.25, -1.34) and -5.15 mg/dl (95% CI: -7.38, -2.93), p-values = 0.0002 and <0.00001 in women and men, respectively], lower levels of plasma saturated fatty acids [-0.09% (95% CI: -0.14, -0.03) and -0.15 % (95% CI: -0.23, -0.08), p-values = 0.001 and 0.0001 in women and men, respectively], and higher levels of plasma polyunsaturated fatty acids [(0.12 % (95% CI: -0.01, 0.25) and 0.39 % (95% CI: 0.19, 0.59), p-values = 0.065 and 0.0001 in women and men, respectively] in the whole population. Plasma carotenoid concentrations were also associated with higher plasma HDL-cholesterol in women [0.47 mg/dl (95% CI: 0.23, 0.72), p-value: 0.0002], and lower fasting plasma glucose in men [-1.35 mg/dl (95% CI: -2.12, -0.59), p-value: 0.001].

Carotenoids in Drug Discovery and Medicine: Pathways and Molecular Targets Implicated in Human Diseases

Carotenoids are isoprenoid-derived natural products produced in plants, algae, fungi, and photosynthetic bacteria. Most animals cannot synthesize carotenoids because the biosynthetic machinery to create carotenoids de novo is absent in animals, except arthropods. Carotenoids are biosynthesized from two C20 geranylgeranyl pyrophosphate (GGPP) molecules made from isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP) via the methylerythritol 4-phosphate (MEP) route. Carotenoids can be extracted by a variety of methods, including maceration, Soxhlet extraction, supercritical fluid extraction (SFE), microwave-assisted extraction (MAE), accelerated solvent extraction (ASE), ultrasound-assisted extraction (UAE), pulsed electric field (PEF)-assisted extraction, and enzyme-assisted extraction (EAE). Carotenoids have been reported to exert various biochemical actions, including the inhibition of the Akt/mTOR, Bcl-2, SAPK/JNK, JAK/STAT, MAPK, Nrf2/Keap1, and NF-κB signaling pathways and the ability to increase cholesterol efflux to HDL. Carotenoids are absorbed in the intestine. A handful of carotenoids and carotenoid-based compounds are in clinical trials, while some are currently used as medicines. The application of metabolic engineering techniques for carotenoid production, whole-genome sequencing, and the use of plants as cell factories to produce specialty carotenoids presents a promising future for carotenoid research. In this review, we discussed the biosynthesis and extraction of carotenoids, the roles of carotenoids in human health, the metabolism of carotenoids, and carotenoids as a source of drugs and supplements.

Pharmaceutical and nutraceutical potential of natural bioactive pigment: astaxanthin

Astaxanthin (3,3'-dihydroxy-β,β-carotene-4,4'-dione) is an orange-red, lipophilic keto-carotenoid pigment. It is majorly found in marine ecosystems particularly in aquatic animals such as salmon, shrimp, trout, krill, crayfish, and so on. It is also synthesized in microalgae Heamatococcus pluvialis, Chlorococcum, Chlorella zofingiensis, red yeast Phaffia rhodozyma and bacterium Paracoccus carotinifaciens. Some aquatic and terrestrial creatures regarded as a primary and secondary sources of the astaxanthin producing and accumulating it through their metabolic pathways. Astaxanthin is the powerful antioxidant, nutritional supplement as well as promising therapeutic compound, observed to have activities against different ravaging diseases and disorders. Researchers have reported remarkable bioactivities of astaxanthin against major non-communicable chronic diseases such as cardiovascular diseases, cancer, diabetes, neurodegenerative, and immune disorders. The current review discusses some structural aspects of astaxanthin. It further elaborates its multiple potencies such as antioxidant, anti-inflammatory, anti-proliferative, anti-cancer, anti-obese, anti-diabetic, anti-ageing, anti-TB, anti-viral, anti-COVID 19, neuro-protective, nephro-protective, and fertility-enhancing properties. These potencies make it a more precious entity in the preventions as well as treatments of prevalent systematic diseases and/or disorders. Also, the review is acknowledging and documenting its powerful bioactivities in relation with the pharmaceutical as well as nutraceutical applicability.

Integration of bioassay and non-target metabolite analysis of tomato reveals that β-carotene and lycopene activate the adiponectin signaling pathway, including AMPK phosphorylation

Adiponectin, an adipokine, regulates glucose metabolism and insulin sensitivity through the adiponectin receptor (AdipoR). In this study, we searched for metabolites that activate the adiponectin signaling pathway from tomato (Solanum lycopersicu). Metabolites of mature tomato were separated into 55 fractions by liquid chromatography, and then each fraction was examined using the phosphorylation assay of AMP-protein kinase (AMPK) in C2C12 myotubes and in AdipoR-knockdown cells by small interfering RNA (siRNA). Several fractions showed AMPK phosphorylation in C2C12 myotubes and siRNA-mediated abrogation of the effect. Non-targeted metabolite analysis revealed the presence of 721 diverse metabolites in tomato. By integrating the activity of fractions on AMPK phosphorylation and the 721 metabolites based on their retention times of liquid chromatography, we performed a comprehensive screen for metabolites that possess adiponectin-like activity. As the screening suggested that the active fractions contained four carotenoids, we further analyzed β-carotene and lycopene, the major carotenoids of food. They induced AMPK phosphorylation via the AdipoR, Ca²⁺/calmodulin-dependent protein kinase kinase and Ca²⁺ influx, in addition to activating glucose uptake via AdipoR in C2C12 myotubes. All these events were characteristic adiponectin actions. These results indicated that the food-derived carotenoids, β-carotene and lycopene, activate the adiponectin signaling pathway, including AMPK phosphorylation.

Recent Advances and the Mechanism of Astaxanthin in Ophthalmological Diseases

Astaxanthin (AST) is a naturally occurring carotenoid that has strong antioxidant, anti-inflammatory, and antiapoptosis effects and is used for the prevention of cancer. There is growing evidence that AST has multiple protective effects against various eye diseases. This article reviews the function and the potential mechanism of AST in dry eye syndrome, keratitis, cataract, diabetic retinopathy, age-related macular degeneration, high intraocular pressure, and other ocular diseases. It provides a theoretical basis for the clinical application of AST as a potential nutraceutical.

Spectropathologic endorsement of ocular carotenoids for early detection of diabetic retinopathy

Diabetic retinopathy (DR) is a common health concern. Unfortunately, the metabolic pathway causing DR is yet to be understood. The carotenoid level in the human body is known to protect the health of the eyes. In this work, resonance Raman spectroscopy and multivariate analysis of the spectral data of human serum are reported as next-generation spectropathologic tools to detect retinal degeneration efficiently. The proposed technique shows promise by endorsing ocular carotenoids as a critical biomarker for such pathosis. Furthermore, the multivariate analysis of the spectral data distinguishes between two different stages of the disease. The machine learning algorithm is used to estimate a significant accuracy of 94% of the proposed model for the classification. As the carotenoid level can be controlled by dietary intake, we believe that the reported results also indicate a therapeutic role of the same in DR.

Possible Effect of Astaxanthin on Obesity-related Increased COVID-19 Infection Morbidity and Mortality

Abstract:

Obesity is defined by the World Health Organisation (WHO) as a body mass index equal to 30 kg/m2 or greater. It is an important and escalating global public health problem. Obesity is known to cause low-grade chronic inflammation, increasing the burden of noncommunicable and possibly communicable diseases. There is considerable evidence that obesity is associated with an increased risk of contracting coronavirus disease 2019 (COVID-19) infection as well as significantly higher COVID-19 morbidity and mortality. It appears plausible that controlling the chronic systemic low-grade inflammation associated with obesity may have a positive impact on the symptoms and the prognosis of COVID-19 disease in obese patients. Astaxanthin (ASTX) is a naturally occurring carotenoid with anti-inflammatory, antioxidant, and immunomodulatory activities. As a nutraceutical agent, it is used as a preventative and a co-treatment in a number of systemic neurological, cardiovascular, and metabolic diseases. This review article will discuss the pathogenesis of COVID-19 infection and the effect of ASTX on obesity and obesity-related inflammation. The potential positive impact of ASTX anti- inflammatory properties in obese COVID-19 patients will be discussed.

Benefits of Fermented Papaya in Human Health

Fermented foods have been used for several years all over the world, due to their unique nutritional characteristics and because fermentation promotes conservation and food security. Moreover, fermented foods and beverages have a strong impact on human gut microbiota. Papaya is the fruit of the Carica papaya plant, traditionally used as a medicinal fruit, but there are also references to the use of the fermented form of this fruit. The main purpose of this review is to provide an improved understanding of fermented papaya nutritional and health applications. A literature search was conducted in the PubMed and Google Scholar databases. Both in vitro and in vivo studies were included. According to the retrieved studies, fermented papaya has proven to be an excellent antioxidant and an excellent nutraceutical adjuvant in combined therapies against several diseases, such as Alzheimer’s disease, allergic reactions, anticancer activity, and anemias. Therefore, it is concluded that fermented papaya has many benefits for human health and can be used as prevention or aid in the treatment of various diseases.

Tomatoes: An Extensive Review of the Associated Health Impacts of Tomatoes and Factors That Can Affect Their Cultivation

Simple Summary

The research outlined in this review paper discusses potential health benefits associated with a diet enriched with tomatoes and tomato products. This includes details of previous studies investigating the anticancer properties of tomatoes, protection against cardiovascular and neurodegenerative diseases and diabetes, maintenance of a healthy gut microbiome, and improved skin health, fertility, immune response, and exercise recovery. The specific parts of a tomato fruit that contribute these health benefits are also outlined. The potential disadvantages to a tomato-rich diet are detailed, especially the consumption of supplements that contain compounds found in tomatoes, such as lycopene. This review also discusses how the cultivation of tomato plants can affect the nutritional value of the fruit harvested. Different environmental growing conditions such as light intensity, growing media, and temperature are explained in terms of the impact they have on the quality of fruit, its nutrient content, and hence the potential health benefits acquired from eating the fruit.

Abstract

This review outlines the health benefits associated with the regular consumption of tomatoes and tomato products. The first section provides a detailed account of the horticultural techniques that can impact the quality of the fruit and its nutritional properties, including water availability, light intensity, temperature, and growing media. The next section provides information on the components of tomato that are likely to contribute to its health effects. The review then details some of the health benefits associated with tomato consumption, including anticancer properties, cardiovascular and neurodegenerative diseases and skin health. This review also discusses the impact tomatoes can have on the gut microbiome and associated health benefits, including reducing the risk of inflammatory bowel diseases. Other health benefits of eating tomatoes are also discussed in relation to effects on diabetes, the immune response, exercise recovery, and fertility. Finally, this review also addresses the negative effects that can occur as a result of overconsumption of tomato products and lycopene supplements.

Nanotechnology-Abetted Astaxanthin Formulations in Multimodel Therapeutic and Biomedical Applications

Astaxanthin (AXT) is one of the most important fat-soluble carotenoids that have abundant and diverse therapeutic applications namely in liver disease, cardiovascular disease, cancer treatment, protection of the nervous system, protection of the skin and eyes against UV radiation, and boosting the immune system. However, due to its intrinsic reactivity, it is chemically unstable, and therefore, the design and production processes for this compound need to be precisely formulated. Nanoencapsulation is widely applied to protect AXT against degradation during digestion and storage, thus improving its physicochemical properties and therapeutic effects. Nanocarriers are delivery systems with many advantages─ease of surface modification, biocompatibility, and targeted drug delivery and release. This review discusses the technological advancement in nanocarriers for the delivery of AXT through the brain, eyes, and skin, with emphasis on the benefits, limitations, and efficiency in practice.

Mechanistic role of astaxanthin derived from shrimp against certain metabolic disorders

Oxidative stress caused by the imbalance between production of oxidants and antioxidants in the body leads to the development of different ailments. The bioactive compounds derived from marine sources are considered to be safe and appropriate to use. Astaxanthin possesses antioxidant activity about 100-500 times higher than other antioxidants such as α-tocopherol and β-carotene. It has numerous health benefits and vital pharmacological properties for the treatment of diseases like diabetes, hypertension, cancer, heart disease, ischemia, neurological disorders, and potential role in liver enzyme gamma-glutamyl transpeptidase which has significance in medicine as a diagnostic marker. The primary source of astaxanthin among crustaceans is shrimps and the presence of astaxanthin protects shrimps from oxidation of polyunsaturated fatty acids and cholesterol. Conclusively, astaxanthin derived from shrimps is very effective against oxidative stress which can lead to certain ailments.

Highly Flexible Hydrogel Dressing with Efficient Antibacterial, Antioxidative, and Wound Healing Performances

Bacterial induced wound infection is very common in real life, but the abuse of antibiotics brings a potential threat to human health. The development of non-antibiotic type antibacterial materials appears...

Phytochemical Content and Antioxidant Activity of Malus domestica Borkh Peel Extracts

Apple is an important dietary source of carotenoids and phenolic compounds, and its regular consumption is associated with several health benefits. The aim of this study was to evaluate the phytochemical composition of fresh peels of four red-skinned (“Champion”, “Generos”, “Idared”, “Florina”) and two yellow-skinned (“Golden Delicious”, “Reinette Simirenko”) apple varieties. Antioxidant activity of apple peel extracts was determined by ferric reducing antioxidant power (FRAP) and ABTS radical scavenging capacity assays. Total carotenoid and polyphenolic contents were determined spectrophotometrically, while the profile of individual carotenoids and anthocyanins (in red-skinned varieties) was analyzed using high-performance liquid chromatography coupled to a photodiode array detector (HPLC-PDA). Carotenoid composition was specific for each variety, and total carotenoid content was slightly higher in yellow-skinned apple peels compared to red-skinned varieties. In contrast, total phenolic content was higher in the peels of red-skinned cultivars. Anthocyanin profile was predominated by cyanidin-3-O-galactoside. Antioxidant potential followed the trend of the total polyphenolic content, being highest in “Florina”, as measured by both FRAP and ABTS assays. Our results demonstrated apple peels have high phytochemical content with diverse compositions, and their regular consumption can be an excellent source of antioxidants.

Microalgae as a Potential Functional Ingredient: Evaluation of the Phytochemical Profile, Antioxidant Activity and In-Vitro Enzymatic Inhibitory Effect of Different Species

The functional food market has been in a state of constant expansion due to the increasing awareness of the impact of the diet on human health. In the search for new natural resources that could act as a functional ingredient for the food industry, microalgae represent a promising alternative, considering their high nutritional value and biosynthesis of numerous bioactive compounds with reported biological properties. In the present work, the phytochemical profile, antioxidant activity, and enzymatic inhibitory effect aiming at different metabolic disorders (Alzheimer's disease, Type 2 diabetes, and obesity) were evaluated for the species Porphyridium purpureum, Chlorella vulgaris, Arthorspira platensis, and Nannochloropsis oculata. All the species presented bioactive diversity and important antioxidant activity, demonstrating the potential to be used as functional ingredients. Particularly, P. purpureum and N. oculata exhibited higher carotenoid and polyphenol content, which was reflected in their superior biological effects. Moreover, the species P. purpureum exhibited remarkable enzymatic inhibition for all the analyses.

Multi-Mechanistic Antidiabetic Potential of Astaxanthin: An Update on Preclinical and Clinical Evidence

Diabetes mellitus (DM) is a cluster of physiological dysfunctions typified by persistent hyperglycemia. Diet plays a paramount role in human health, and regular consumption of a fruit- and vegetable-rich diet can delay or prevent DM and its associated complications. The promising effect of fruits and vegetables could be partly attributed to their antioxidant constituents, including carotenoids. Carotenoids are natural antioxidants that occur in many vegetables, fruits, microalgae, and other natural sources. Astaxanthin is a xanthophyll carotenoid predominantly present in microalgae and some red-colored marine organisms. It is currently marketed as a health supplement and is well-known for its antioxidant capacity. Accumulating evidence indicates that astaxanthin exerts its beneficial effects against DM by acting on various molecular targets and signaling pathways in multiple organs/tissues. Astaxanthin can lower blood glucose levels by preserving β-cell function, improving insulin resistance (IR), and increasing insulin secretion. This manuscript summarizes the connection between glucose homeostasis, oxidative stress, and DM. This is followed by a review of recent studies on astaxanthin's pharmacological effects against IR, microvascular (diabetic retinopathy, diabetic nephropathy, and neurological damage), and macrovascular DM complications emphasizing the cellular and molecular mechanisms involved. A few lines of clinical evidence supporting its antidiabetic potential are also highlighted.

Astaxanthin: A super antioxidant from microalgae and its therapeutic potential

Astaxanthin is a ketocarotenoid, super antioxidant molecule. It has higher antioxidant activity than a range of carotenoids, thus has applications in cosmetics, aquaculture, nutraceuticals, therapeutics, and pharmaceuticals. Naturally, it is derived from Haematococcus pluvialis via a one-stage process or two-stage process. Natural astaxanthin significantly reduces oxidative and free-radical stress as compared to synthetic astaxanthin. The present review summarizes all the aspects of astaxanthin, including its structure, chemistry, bioavailability, and current production technology. Also, this paper gives a detailed mechanism for the potential role of astaxanthin as nutraceuticals for cardiovascular disease prevention, skin protection, antidiabetic and anticancer, cosmetic ingredient, natural food colorant, and feed supplement in poultry and aquaculture. Astaxanthin is one of the high-valued microalgae products of the future. However, due to some risks involved or not having adequate research in terms of long-term consumption, it is still yet to be explored by food industries. Although the cost of naturally derived astaxanthin is high, it accounts for only a 1% share in total astaxanthin available in the global market. Therefore, scientists are looking for ways to cut down the cost of natural astaxanthin to be made available to consumers.

Attenuating Effect of Chlorella Extract on NLRP3 Inflammasome Activation by Mitochondrial Reactive Oxygen Species

The NOD-like receptor family, pyrin domain-containing protein 3 (NLRP3) inflammasome has been linked to the pathogenesis of a wide variety of human diseases. Although many drugs and inhibitors have been developed to treat NLRP3-associated diseases, only limited clinical data support their efficacy and safety. Chlorella, a unicellular green alga that is widely and safely used as a food supplement, contains various antioxidants. In this study, we obtained a fat-soluble extract from Chlorella (CE) and demonstrated that it reduced NLRP3 inflammasome activation by inhibiting mitochondrial reactive oxygen species and caspase-1 activation. In addition, CE supplementation attenuated lipopolysaccharide-induced interleukin 1β transcription through activation of hypoxia-inducible factor 1α in vitro and in vivo. As Chlorella is a safe and useful food supplement, it may be a practical pharmacological approach for treating NLRP3-driven diseases.

Potential Glioprotective Strategies Against Diabetes-Induced Brain Toxicity

Astrocytes are crucial for the maintenance of brain homeostasis by actively participating in the metabolism of glucose, which is the main energy substrate for the central nervous system (CNS), in addition to other supportive functions. More specifically, astrocytes support neurons through the metabolic coupling of synaptic activity and glucose utilization. As such, diabetes mellitus (DM) and consequent glucose metabolism disorders induce astrocyte damage, affecting CNS functionality. Glioprotective molecules can promote protection by improving glial functions and avoiding toxicity in different pathological conditions, including DM. Therefore, this review discusses specific pathomechanisms associated with DM/glucose metabolism disorder-induced gliotoxicity, namely astrocyte metabolism, redox homeostasis/mitochondrial activity, inflammation, and glial signaling pathways. Studies investigating natural products as potential glioprotective strategies against these deleterious effects of DM/glucose metabolism disorders are also reviewed herein. These products include carotenoids, catechins, isoflavones, lipoic acid, polysaccharides, resveratrol, and sulforaphane.

Oxidative Stress: Pathogenetic Role in Diabetes Mellitus and Its Complications and Therapeutic Approaches to Correction

The review presents modern views about the role of oxidative stress reactions in the pathogenesis of types 1 and 2 diabetes mellitus and their complications based on the analysis of experimental and clinical studies. The sources of increased ROS generation in diabetes are specified, including the main pathways of altered glucose metabolism, oxidative damage to pancreatic β-cells, and endothelial dysfunction. The relationship between oxidative stress, carbonyl stress, and inflammation is described. The significance of oxidative stress reactions associated with hyperglycemia is considered in the context of the “metabolic memory” phenomenon. The results of our studies demonstrated significant ethnic and age-related variability of the LPO—antioxidant defense system parameters in patients with diabetes mellitus, which should be considered during complex therapy of the disease. Numerous studies of the effectiveness of antioxidants in diabetes mellitus of both types convincingly proved that antioxidants should be a part of the therapeutic process. Modern therapeutic strategies in the treatment of diabetes mellitus are aimed at developing new methods of personalized antioxidant therapy, including ROS sources targeting combined with new ways of antioxidant delivery.

Vitamin A Status Improvement in Obesity: Findings and Perspectives Using Encapsulation Techniques

The association between obesity and vitamin A has been studied. Some studies point to the anti-obesity activity related to this vitamin, carotenoids with provitamin A activity, and carotenoid conversion products. This performance has been evaluated in respect of adipogenesis, metabolic activity, oxidation processes, secretory function, and oxidative stress modulation, showing a new property attributed to vitamin A in preventing and treating obesity. However, vitamin A and its precursors are highly sensitive and easily degraded when subjected to heat, the presence of light, and oxygen, in addition to losses related to the processes of digestion and absorption. In this context, encapsulation presents itself as an alternative capable of increasing vitamin A’s stability in the face of unfavorable conditions in the environment, which can reduce its functionality. Considering that vitamin A’s status shows a strong correlation with obesity and is an innovative theme, this article addresses the associations between vitamin A’s consumption and its precursors, encapsulated or not, and its physiological effects on obesity. The present narrative review points out those recent studies that demonstrate that vitamin A and its encapsulated precursors have the most preserved functionality, which guarantees better effects on obesity therapy.

Evaluation of Storage and Freezing, Baking, and Boiling Treatments on Total Carotenoids Content in the Fruits of Selected Cucurbita moschata Duch. Varieties

Cucurbita moschata Duch. is a seasonal crop, appreciated for its nutrimental and bioactive components especially carotenoids. From the whole edible plant, fruit is most often consumed which can be stored and also processed. Six varieties—Liscia, Matilda, Orange, Serpentine, UG 205 F1, and Waltham—of Cucurbita moschata Duch. were investigated, in order to analyze and evaluate the changes in total carotenoids content in the pulp during storage and after the effect of heat treatments—freezing, baking, and cooking (water boiling). The average total carotenoids content ranged from 3.32 mg/100 g (Serpentine) to 9.35 mg/100 g fresh matter (FM) (Orange). After 60 days of storage, a slight increase in the total carotenoids content of all analyzed varieties was observed. The values of the monitored varieties ranged from 4.18 mg/100 g FM (Serpentine), which represents a 26% increase to 10.96 mg/100 g FM (Orange), where a 17% increase was observed. After 120 days of storage, the results were mixed. In some varieties (Liscia and Matilda), the total carotenoid content decreased, while in the varieties Serpentine, UG 205 F1, and Waltham, its content increased slightly (11%, 3%, and 11%), but the content of the Orange variety remained unchanged. The total carotenoids increment after 60 and 120 days of storage in the dry matter (DM) was statistically significant, as well as the effect of the variety. The total carotenoid content of cooked samples of all varieties increased, from 119.78 mg/100 g DM (Waltham) to 255.19 mg/100 g DM (Orange). After baking, an average of 12% increase in the total content of carotenoids was recorded, after freezing, a decrease in its level of 5% was indicated. The findings of this work show that Cucurbita moschata Duch. is a good source of carotenoids, even after several weeks of storage and after exposure to heat treatments.