Phytic acid and myo-inositol support adipocyte differentiation and improve insulin sensitivity in 3T3-L1 cells

The Relevance of Phytate for the Treatment of Chronic Kidney Disease

Diets high in plant-based foods are commonly recommended for people with CKD. One putative advantage of these diets is reduced intestinal phosphate absorption. This effect has been ascribed to phytic acid (myoinositol hexaphosphoric acid) and its anion, phytate, that are present in many plant foods, particularly in the seeds, nuts, grains, and fruits of plants. This article reviews the structure and many actions of phytate with particular reference to its potential effects on people with CKD. Phytate binds avidly to and can reduce gastrointestinal absorption of the phosphate anion and many macrominerals and trace elements including iron, zinc, calcium, and magnesium. This has led some opinion leaders to label phytate as an anti-nutrient. The human intestine lacks phytase; hence, phytate is essentially not degraded in the small intestine. A small amount of phytate is absorbed from the small intestine, although phytate bound to phosphate is poorly absorbed. Clinical trials in maintenance hemodialysis patients indicate that intravenously administered phytate may decrease hydroxyapatite formation, vascular calcification, and calciphylaxis. Orally administered phytate or in vitro studies indicate that phytate may also reduce osteoporosis, urinary calcium calculi formation, and dental plaque formation. Phytate seems to have anti-inflammatory and antioxidant effects, at least partly because of its ability to chelate iron. Other potential therapeutic roles for phytate, not definitively established, include suppression of cancer formation, reduction in cognitive decline that occurs with aging, and amelioration of certain neurodegenerative diseases and several gastrointestinal and metabolic disorders. These latter potential benefits of phytate are supported by cell or animal research or observational studies in humans. Many of the above disorders are particularly common in patients with CKD. Definitive clinical trials to identify potential therapeutic benefits of phytate in patients with CKD are clearly warranted.

Insulin-Heart Axis: Bridging Physiology to Insulin Resistance

Insulin signaling is vital for regulating cellular metabolism, growth, and survival pathways, particularly in tissues such as adipose, skeletal muscle, liver, and brain. Its role in the heart, however, is less well-explored. The heart, requiring significant ATP to fuel its contractile machinery, relies on insulin signaling to manage myocardial substrate supply and directly affect cardiac muscle metabolism. This review investigates the insulin-heart axis, focusing on insulin's multifaceted influence on cardiac function, from metabolic regulation to the development of physiological cardiac hypertrophy. A central theme of this review is the pathophysiology of insulin resistance and its profound implications for cardiac health. We discuss the intricate molecular mechanisms by which insulin signaling modulates glucose and fatty acid metabolism in cardiomyocytes, emphasizing its pivotal role in maintaining cardiac energy homeostasis. Insulin resistance disrupts these processes, leading to significant cardiac metabolic disturbances, autonomic dysfunction, subcellular signaling abnormalities, and activation of the renin-angiotensin-aldosterone system. These factors collectively contribute to the progression of diabetic cardiomyopathy and other cardiovascular diseases. Insulin resistance is linked to hypertrophy, fibrosis, diastolic dysfunction, and systolic heart failure, exacerbating the risk of coronary artery disease and heart failure. Understanding the insulin-heart axis is crucial for developing therapeutic strategies to mitigate the cardiovascular complications associated with insulin resistance and diabetes.

Inositols in treating polycystic ovary syndrome and non-insulin dependent diabetes mellitus: now and the future

INTRODUCTION

This Expert Opinion covers recent updates in the use of Inositol in polycystic ovary syndrome (PCOS) and type II diabetes and gives support to researchers and clinicians.

AREAS COVERED

This article discusses the role of Myo-Inositol (MI) and D-Chiro-Inositol (DCI) in physiological function, the use of MI in PCOS, the risks of using DCI in reproductive conditions, the 40:1 combination of MI/DCI in PCOS. Furthermore, we discuss the issues of insulin resistance and how α-lactalbumin may increase the intestinal bioavailability of MI. The paper then transitions to talk about the use of inositols in diabetes, including type II diabetes, Gestational Diabetes Mellitus (GDM), and double diabetes. Literature searches were performed with the use of PubMed, Google Scholar, and Web of Science between July and October 2023.

EXPERT OPINION

Inositol therapy has grown in the clinical field of PCOS, with it demonstrating an efficacy like that of metformin. The use of α-lactalbumin has further supported the use of MI, as issues with intestinal bioavailability have been largely overcome. In contrast, the effect of inositol treatment on the different PCOS phenotypes remains an outstanding question. The use of inositols in type II diabetes requires further study despite promising analogous data from GDM.

Cellular and Molecular Activities of IP6 in Disease Prevention and Therapy

IP6 (phytic acid) is a naturally occurring compound in plant seeds and grains. It is a poly-phosphorylated inositol derivative that has been shown to exhibit many biological activities that accrue benefits in health and diseases (cancer, diabetes, renal lithiasis, cardiovascular diseases, etc.). IP6 has been shown to have several cellular and molecular activities associated with its potential role in disease prevention. These activities include anti-oxidant properties, chelation of metal ions, inhibition of inflammation, modulation of cell signaling pathways, and modulation of the activities of enzymes and hormones that are involved in carbohydrate and lipid metabolism. Studies have shown that IP6 has anti-oxidant properties and can scavenge free radicals known to cause cellular damage and contribute to the development of chronic diseases such as cancers and cardiovascular diseases, as well as diabetes mellitus. It has also been shown to possess anti-inflammatory properties that may modulate immune responses geared towards the prevention of inflammatory conditions. Moreover, IP6 exhibits anti-cancer properties through the induction of cell cycle arrest, promoting apoptosis and inhibiting cancer cell growth. Additionally, it has been shown to have anti-mutagenic properties, which reduce the risk of malignancies by preventing DNA damage and mutations. IP6 has also been reported to have a potential role in bone health. It inhibits bone resorption and promotes bone formation, which may help in the prevention of bone diseases such as osteoporosis. Overall, IP6's cellular and molecular activities make it a promising candidate for disease prevention. As reported in many studies, its anti-inflammatory, anti-oxidant, and anti-cancer properties support its inclusion as a dietary supplement that may protect against the development of chronic diseases. However, further studies are needed to understand the mechanisms of action of this dynamic molecule and its derivatives and determine the optimal doses and appropriate delivery methods for effective therapeutic use.

Daily phytate intake increases adiponectin levels among patients with diabetes type 2: a randomized crossover trial

AIM

Adiponectin, a major adipokine secreted by adipose tissue, has been shown to improve insulin sensitivity. Myo-inositol hexaphosphate (phytate; InsP6) is a natural compound that is abundant in cereals, legumes, and nuts that has demonstrated to have different beneficial properties in patients with diabetes type 2.

METHODS

We performed a randomized crossover trial to investigate the impact of daily consumption of InsP6 on serum levels of adiponectin, TNF-alpha, IL-6, and IL-1beta in patients with type 2 diabetes mellitus (T2DM; n = 39). Thus, we measure serum levels of these inflammatory markers, classic vascular risk factors, and urinary InsP6 at baseline and at the end of the intervention period.

RESULTS

Patients who consumed InsP6 supplements for 3 months had higher levels of adiponectin and lower HbA1c than those who did not consume InsP6. No differences were found in TNF-alpha, IL-6, and IL-1beta.

CONCLUSION

This is the first report to show that consumption of InsP6 increases plasma adiponectin concentration in patients with T2DM. Consequently, our findings indicate that following a phytate-rich diet has beneficial effects on adiponectin and HbA1c concentrations and it could help to prevent or minimize diabetic-related complications.

Antidiabetic Potential of Commonly Available Fruit Plants in Bangladesh: Updates on Prospective Phytochemicals and Their Reported MoAs

Diabetes mellitus is a life-threatening disorder affecting people of all ages and adversely disrupts their daily functions. Despite the availability of numerous synthetic-antidiabetic medications and insulin, the demand for the development of novel antidiabetic medications is increasing due to the adverse effects and growth of resistance to commercial drugs in the long-term usage. Hence, antidiabetic phytochemicals isolated from fruit plants can be a very nifty option to develop life-saving novel antidiabetic therapeutics, employing several pathways and MoAs (mechanism of actions). This review focuses on the antidiabetic potential of commonly available Bangladeshi fruits and other plant parts, such as seeds, fruit peals, leaves, and roots, along with isolated phytochemicals from these phytosources based on lab findings and mechanism of actions. Several fruits, such as orange, lemon, amla, tamarind, and others, can produce remarkable antidiabetic actions and can be dietary alternatives to antidiabetic therapies. Besides, isolated phytochemicals from these plants, such as swertisin, quercetin, rutin, naringenin, and other prospective phytochemicals, also demonstrated their candidacy for further exploration to be established as antidiabetic leads. Thus, it can be considered that fruits are one of the most valuable gifts of plants packed with a wide spectrum of bioactive phytochemicals and are widely consumed as dietary items and medicinal therapies in different civilizations and cultures. This review will provide a better understanding of diabetes management by consuming fruits and other plant parts as well as deliver innovative hints for the researchers to develop novel drugs from these plant parts and/or their phytochemicals.

Effect of psyllium husk and wheat mill bran fractions on the microstructure and mixograph characteristics of Arabic bread

When psyllium husk, wheat bran and germ was added, Incorporation of psyllium and wheat bran may affect the dough structure, dough rheology as well as the final quality of baked Arabic flat bread, which, thus, became important for this study. Scanning Electron Micrographs (SEM) taken on Arabic bread, depicted both intact small and the large starch granules on the outer crust area. This was mainly due to the rapid loss of moisture from the Arabic bread surface during intense baking operation leaving less moisture for gelatinization to take place. With psyllium added to WWF at 0, 3, and 5 % level, the peak time was increased from 3 to 4.5 min. The ascending and descending angle values were more or less identical in all the samples except with wheat germ addition, whereas much lower values (51 to 58°) for these parameters were observed, indicating a faster rate of dough breakdown. With psyllium, fine- and coarse bran addition to WWF, a corresponding increase in peak time was observed. Ascending and descending angles showed similar trends to that of the WWF and psyllium combinations. Use of falling number apparatus is an indirect method of measuring the diastatic enzyme activity in cereal flours. WGF showed lower falling-number values (502 s) than the WWF (607 s). Addition of fine bran to WWF lowered the falling number (607 to 563 s) whereas with coarse wheat bran and germ, these values were increased.

Evaluation of the metabolomic profile through 1H-NMR spectroscopy in ewes affected by postpartum hyperketonemia

Ketosis is one of the most important health problems in dairy sheep. The aim of this study was to evaluate the metabolic alterations in hyperketonemic (HYK) ewes. Forty-six adult Sardinian ewes were enrolled between 7 ± 3 days post-partum. Blood samples were collected from the jugular vein using Venosafe tubes containing clot activator from jugular vein after clinical examination. The concentration of β-hydroxybutyrate (BHB) was determined in serum and used to divide ewes into assign ewes into: Non-HYK (serum BHB < 0.80 mmol/L) and HYK (serum BHB ≥ 0.80 mmol/L) groups. Animal data and biochemical parameters of groups were examined with one-way ANOVA, and metabolite differences were tested using a t-test. A robust principal component analysis model and a heatmap were used to highlight common trends among metabolites. Over-representation analysis was performed to investigate metabolic pathways potentially altered in connection with BHB alterations. The metabolomic analysis identified 54 metabolites with 14 different between groups. These metabolites indicate altered ruminal microbial populations and fermentations; an interruption of the tricarboxylic acid cycle; initial lack of glucogenic substrates; mobilization of body reserves; the potential alteration of electron transport chain; influence on urea synthesis; alteration of nervous system, inflammatory response, and immune cell function.

Maternal diabetes negatively impacts fetal health

Diabetes is a chronic metabolic disease affecting an increasing number of people. Although diabetes has negative health outcomes for diagnosed individuals, a population at particular risk are pregnant women, as diabetes impacts not only a pregnant woman's health but that of her child. In this review, we cover the current knowledge and unanswered questions on diabetes affecting an expectant mother, focusing on maternal and fetal outcomes.

Dietary administration of D-chiro-inositol attenuates sex-specific metabolic imbalances in the 5xFAD mouse model of Alzheimer's disease

Increasing evidence shows that hypothalamic dysfunction, insulin resistance, and weight loss precede and progress along with the cognitive decline in sporadic Alzheimer's Disease (AD) with sex differences. This study aimed to determine the effect of oral dietary administration of D-Chiro-inositol (DCI), an inositol used against insulin resistance associated with polycystic ovary, on the occurrence of metabolic disorders in the transgenic 5xFAD mouse model of AD (FAD: Family Alzheimer's Disease). DCI was administered from 6 to 10 months of age to male and female 5xFAD mice and control (non-Tg) littermates. Energy balance and multiple metabolic and inflammatory parameters in the hypothalamus, liver and plasma were evaluated to assess the central and peripheral effects of DCI. Results indicated that weight loss and reduced food intake in 5xFAD mice were associated with decreased neuropeptides controlling food intake and the appearance of a pro-inflammatory state in the hypothalamus. Oral administration of DCI partially restored energy balance and hypothalamic parameters, highlighting an increased expression of Npy and Agrp and female-specific downregulation of Gfap and Igf1. DCI also partially normalized impaired insulin signaling and circulating insulin, GLP-1, and GIP deficiencies in 5xFAD mice. Principal component analysis of metabolic parameters indicated the presence of a female-specific fatty liver in 5xFAD mice: DCI administration reversed hepatic fat accumulation, β-oxidation, inflammation and increased GOT and GPT levels. Our study depicts that metabolic impairment along with the cognitive decline in a mouse model of AD, which is exacerbated in females, can be ameliorated by oral supplementation with insulin-sensitizing DCI.

Effect of supplemental myo-inositol on growth performance and apparent total tract digestibility of weanling piglets fed reduced protein high phytate diets and intestinal epithelial cell proliferation and function

Myo-inositol is a breakdown product of phytate produced in the gut through the action of phytase. Although the effect of phytase-released phosphorus (P) on growth performance of animals has been well characterized, there is still little understanding of effect of myo-inositol. The first objective of this study was to determine the effects of added myo-inositol to a phytate rich low protein diet on growth performance and apparent total tract digestibility (ATTD) in growing piglets. The second objective was to determine whether myo-inositol could directly affect intestinal epithelial cell proliferation and function for which we used intestinal porcine epithelial cells (IPEC-J2). A total of 128 weanling piglets were allotted to four dietary treatments consisting of eight replicates per treatment and four piglets per replicate in a randomized complete block design for four weeks. The four experimental diets comprised the positive control (PC; 20% crude protein (CP), negative control (NC; 17% CP), negative control plus 2.0g/kg myo-inositol (NC+INO; 17% CP) and negative control plus 3000FTU/kg phytase (NC+PHY; 17% CP). Average daily feed intake (ADFI), average daily gain (ADG), gain-feed ratio (G: F) were recorded. Phytase supplementation in the protein-deficient NC diet increased the G:F ratio (P < 0.05) without myo-inositol effect on growth performance. Phosphorus digestibility in the phytase supplemented group increased compared to the PC, NC, and NC+INO groups whereas plasma myo-inositol concentration was significantly higher (P < 0.05) in the NC+INO group. Due to lack of myo-inositol effect on growth performance, an additional in vitro study was conducted to determine direct effect of myo-inositol on the intestinal epithelium that might not be reflected in growth performance. Myo-inositol increased the mRNA abundance of selected nutrient transporters in a concentration-dependent manner (P < 0.05). Myo-inositol also enhanced barrier integrity in the IPEC-J2 monolayer by increasing the transepithelial electrical resistance (TEER) with reduced paracellular permeability of FITC-dextran (P < 0.05). In conclusion, despite the lack of myo-inositol effect on animal performance, the in vitro data indicates that myo-inositol may directly regulate gut barrier integrity. Addition of myo-inositol to pig diets at levels that enhance intestinal epithelial cell function may result in effects on growth performance and gut health of pigs.

Psidium guajava L. leaf extract inhibits adipocyte differentiation and improves insulin sensitivity in 3T3-L1 cells

BACKGROUND/OBJECTIVES

Psidium guajava L. (guava) leaves have been shown to exhibit hypoglycemic and antidiabetic effects in rodents. This study investigated the effects of guava leaf extract on adipogenesis, glucose uptake, and lipolysis of adipocytes to examine whether the antidiabetic properties are mediated through direct effects on adipocytes.

MATERIALS/METHODS

3T3-L1 cells were treated with 25, 50, 100 µg/mL of methanol extract from guava leaf extract (GLE) or 0.1% dimethyl sulfoxide as a control. Lipid accumulation was evaluated with Oil Red O Staining and AdipoRed assay. Immunoblotting was performed to measure the expression of adipogenic transcription factors, fatty acid synthase (FAS), and AMP-activated protein kinase (AMPK). Glucose uptake under basal or insulin-stimulated condition was measured using a glucose analog 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-D-glucose. Lipolysis from fully differentiated adipocytes was measured by free fatty acids release into the culture medium in the presence or absence of epinephrine.

RESULTS

Oil Red O staining and AdipoRed assay have shown that GLE treatment reduced lipid accumulation during adipocyte differentiation. Mitotic clonal expansion, an early essential event for adipocyte differentiation, was inhibited by GLE treatment. GLE inhibited the expression of transcription factors involved in adipocyte differentiation, such as peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein α (C/EBPα), and sterol regulatory element-binding protein-1c (SREBP-1c). FAS expression was also decreased while the phosphorylation of AMPK was increased by GLE treatment. In addition, GLE increased insulin-induced glucose uptake into adipocytes. In lipid-filled mature adipocytes, GLE enhanced epinephrine-induced lipolysis but reduced basal lipolysis dose-dependently.

CONCLUSIONS

The results show that GLE inhibits adipogenesis and improves adipocyte function by reducing basal lipolysis and increasing insulin-stimulated glucose uptake in adipocytes, which can be partly associated with antidiabetic effects of guava leaves.

Novel Mg-Incorporated Micro-Arc Oxidation Coatings for Orthopedic Implants Application

In this study, Ti-6Al-4V alloy samples were processed by micro-arc oxidation (MAO) in phytic acid (H₁₂Phy) electrolytes with the addition of different concentrations of EDTA-MgNa₂ (Na₂MgY) and potassium hydroxide (KOH). The surface characterization and cytocompatibility of MAO-treated samples were evaluated systematically. H₁₂Phy is a necessary agent for MAO coating formation, and the addition of Na₂MgY and KOH into the electrolytes increases the surface roughness, micropore size and Mg contents in the coatings. The MAO coatings are primarily composed of anatase, rutile, MgO and Mg₃(PO₄)₂. Magnesium (Mg) ions in the electrolytes enter into MAO coatings by diffusion and electromigration. The MAO coatings containing 2.97 at% Mg show excellent cell viability, adhesion, proliferation, alkaline phosphatase activity, extracellular matrix (ECM) mineralization and collagen secretion, but the cytocompatibility of the MAO coatings containing 6.82 at% Mg was the worst due to the excessively high Mg content. Our results revealed that MAO coatings with proper Mg contents improve the cytocompatibility of the Ti-6Al-4V alloys and have large potential in orthopedic applications.

Development of functional foods using psyllium husk and wheat bran fractions: Phytic acid contents

Wheat grain is a rich source of phosphorus which is present mostly as phytic acid and is distributed mainly in the bran and germ fractions. Phytic acid has now been recognized as an important phytochemical having antioxidant properties. This study deals with the determination of total as well as phytic phosphorus contents of psyllium (PS), course (CB) and fine wheat bran (FB) enriched pan bread and Arabic flat bread. The concentration of phytic acid in CB, FB, wheat germ, wholegrain wheat flour (WGF), white wheat flour (WWF), and psyllium were found to be 8.86 mg/g, 8.52 mg/g, 6.05 mg/g, 1.74 mg/g, 0.46 mg/g and 0.02 mg/g, respectively. Most of the phosphorus existed as phytic phosphorus (74.7–90.8%) in FB, CB, germ, and WGF as compared to only 42.6% in WWF. The level of phytic phosphorus in pan bread containing 10% CB, 20% FB (both containing with 5% PS) was found to be 0.63 mg/g and 1.53 mg/g respectively, as compared to only 0.34 mg/g in WWF pan bread, and 0.90 mg/g in WGF pan bread. The phytic phosphorus content in Arabic bread made with WGF and 3% psyllium was 1.32 mg/g as compared to only 0.48 mg/g in WWF Arabic flat bread. The results obtained indicate that the level of phytic phosphorus significantly increased in bread formulations containing CB, FB, and WGF, but no change with psyllium addition was observed. Adding these wheat mill fractions, and psyllium will enable bakeries not only to produce fiber-enriched pan bread and Arabic bread but would also benefit consumers to increase their dietary fiber intakes, and health-promoting phytochemicals coming from wheat bran and germ fractions.

Contrasting the effects of phytase and pure myo-inositol on the performance, digestibility, blood and egg yolk inositol levels and digestion physiology of laying hens

ABSRACT1. An experiment was designed to compare the effects of supplementing laying hen diets with phytase and myo-inositol (inositol).2. Five diets were formulated: high balanced protein (HBP - 840 mg of Dlys/hen/day), HBP with inositol (HBP+I - 0.16%), reduced balance protein (RBP - 672 mg of Dlys/hen/day), RBP with inositol (RBP+I - 0.16%) and RBP with phytase (RBP+P - 3000 FTU/kg).3. Laying hen production, inositol concentrations, digestive tract morphology, amino acid digestibility and intestinal inositol transporters transcript abundance were evaluated. Data were analysed with a one-way ANOVA in SAS 9.4. Contrasts were used to assess the effect of protein, inositol, phytase and phytase vs. inositol. Differences were accepted when P ≤ 0.05.4. No effect on hen-day egg production or feed efficiency was found. However, feed intake and the incidence of abnormally shaped eggs were 0.77 g/h/d and 0.17% higher, respectively, in inositol treatments. Inositol decreased egg specific gravity from 1.088 to 1.0865.5. Inositol concentration in egg yolk was similar among HBP+I, RBP+I and RBP+P, and higher than for the HBP and RBP diet groups. Both gizzard and ileal digesta were enriched in inositol in all supplemented treatments, and phytase supplementation decreased the level of IP5 and IP6 in the gizzard and ileum. Generally, neither phytase or inositol affected amino acid digestibility.6. Inositol increased transcript abundance of alkaline phosphatase in the ileum, while phytase upregulated duodenal alkaline phosphatase and SMIT1, jejunal SMIT2 and reduced ileal HMIT and SMIT1 abundance.7. In conclusion, no effect of phytase or inositol was found for laying hen production performance or amino acid digestibility, but egg quality was reduced by inositol supplementation. Inositol concentration in egg yolk was similar among supplemented treatments.

Gas Chromatography-Mass Spectrometry Coupled with Multivariate Statistical Analysis to Identify the Alpha Glucosidase Inhibitors from Flesh of Salacca zalacca Fruits and Their Molecular Docking Studies

Fruit of salak (Salaaca zalacca) is traditionally used and commercialized as an antidiabetic agent. However, scientific evidence to prove this folk claim is quite lacking. Therefore, this research was aimed to evaluate the α-glucosidase inhibition activity of S. zalacca fruit and identify the bioactive compounds. The fruits were extracted by different ratios of ethanol and water (0, 20, 40, 60, 80, 100%, v/v) to get E0 (100% water), E20 (20% ethanol), E40 (40% ethanol), E60 (60% ethanol), E80 (80% ethanol), and E100 (100% ethanol) extracts. The extracts obtained were subjected to the α-glucosidase inhibitory assay. Gas chromatography-mass spectrometry- (GC-MS-) based metabolomics approach was used in profiling the bioactive metabolites present in the extracts. Orthogonal partial least square (OPLS) was used to correlate GC-MS data and α-glucosidase assay results to identify the possible chemical markers. All active compounds identified were subjected to molecular docking. The extracts from the S. zalacca fruit showed potent inhibition activity against α-glucosidase. The IC50 values from the α-glucosidase inhibitory assay ranged between 16 and 275 µg/ml. Overall, E60 displayed significantly higher α-glucosidase inhibition activity, while E0 showed the lowest α-glucosidase inhibition activity. Major compounds detected in S. zalacca fruits were sugars, fatty acids, and sterols, including myo-inositol, palmitic acid, stearic acid, and β-sitosterol. Moreover, the results obtained from molecular docking indicated that palmitic acid and β-sitosterol were close to the active side of the enzyme. Some of the residues that interacted include HID295, ASN259, LEU313, LYS125, PHE159, VAL216, PHE178, TYR72, TYR158, HIE315, ARG315, and PHE303. The bioassay result strongly suggests that E60 extract from S. zalacca fruits has potential α-glucosidase inhibitory activity. The hydrophobic compounds, including palmitic acid and β-sitosterol, were found to induce the α-glucosidase inhibition activity.

D-Chiro-Inositol Regulates Insulin Signaling in Human Adipocytes

D-Chiro-Inositol (D-Chiro-Ins) is a secondary messenger in the insulin signaling pathway. D-Chiro-Ins modulates insulin secretion, the mitochondrial respiratory chain, and glycogen storage. Due to these actions D-Chiro-Ins has been proposed to correct defective insulin function in a variety of conditions characterized by metabolic dysfunction, such as polycystic ovary syndrome (PCOS), obesity, gestational diabetes and fat accumulation at menopause. Since it is unclear whether D-Chiro-Ins directly acts on adipocytes, we aimed to study D-Chiro-Ins's actions on adipocyte viability, proliferation, differentiation, and insulin-related protein expression using a human adipocyte cell line derived from Simpson-Golabi-Behmel Syndrome (SGBS) which fully differentiates to mature adipocytes. Throughout differentiation, cells were treated with D-Chiro-Ins, 17β-estradiol (E2) or Insulin. Cell viability and proliferation were not affected by D-Chiro-Ins, then D-Chiro-Ins promoted cell differentiation only during the final days of the process, while E2 enhanced it from the first phases. D-Chiro-Ins stimulated lipid storage and the production of big lipid droplets, thus reducing the content of free fatty acids. We also found that D-Chiro-Ins, either alone or in combination with insulin and E2 increased the expression and activation of insulin receptor substrate-1 (IRS1) and glucose transporter type 4 (GLUT4). In conclusion, this work shows that D-Chiro-Ins plays a direct role in the differentiation and in the function of human adipocytes, where it synergizes with insulin and estrogen through the recruitment of signal transduction pathways involved in lipid and glucose storage. These findings give clear insights to better understand the actions of D-Chiro-Ins on fat metabolism in women in physiology and in a variety of diseases.

A review of the role of inositols in conditions of insulin dysregulation and in uncomplicated and pathological pregnancy

Inositols, a group of 6-carbon polyols, are highly bioactive molecules derived from diet and endogenous synthesis. Inositols and their derivatives are involved in glucose and lipid metabolism and participate in insulin-signaling, with perturbations in inositol processing being associated with conditions involving insulin resistance, dysglycemia and dyslipidemia such as polycystic ovary syndrome and diabetes. Pregnancy is similarly characterized by substantial and complex changes in glycemic and lipidomic regulation as part of maternal adaptation and is also associated with physiological alterations in inositol processing. Disruptions in maternal adaptation are postulated to have a critical pathophysiological role in pregnancy complications such as gestational diabetes and pre-eclampsia. Inositol supplementation has shown promise as an intervention for the alleviation of symptoms in conditions of insulin resistance and for gestational diabetes prevention. However, the mechanisms behind these affects are not fully understood. In this review, we explore the role of inositols in conditions of insulin dysregulation and in pregnancy, and identify priority areas for research. We particularly examine the role and function of inositols within the maternal-placental-fetal axis in both uncomplicated and pathological pregnancies. We also discuss how inositols may mediate maternal-placental-fetal cross-talk, and regulate fetal growth and development, and suggest that inositols play a vital role in promoting healthy pregnancy.

Alleviation of the Adverse Effect of Dietary Carbohydrate by Supplementation of Myo-Inositol to the Diet of Nile Tilapia (Oreochromis niloticus)

This study investigated the effect of dietary myo-inositol (MI) on alleviating the adverse effect of the high carbohydrate diet in Nile tilapia (Oreochromis niloticus). Six diets contained either low carbohydrate (LC 30%) or high carbohydrate (HC 45%) with three levels of MI supplementation (0, 400 and 1200 mg/kg diet) to each level of the carbohydrate diet. After an 8-week trial, the fish fed 400 mg/kg MI under HC levels had the highest weight gain and fatness, but the fish fed 1200 mg/kg MI had the lowest hepatosomatic index, visceral index and crude lipid in the HC group. The diet of 1200 mg/kg MI significantly decreased triglyceride content in the serum and liver compared with those fed the MI supplemented diets regardless of carbohydrate levels. Dietary MI decreased triglyceride accumulation in the liver irrespective of carbohydrate levels. The content of malondialdehyde decreased with increasing dietary MI at both carbohydrate levels. Fish fed 1200 mg/kg MI had the highest glutathione peroxidase, superoxide dismutase, aspartate aminotransferase and glutamic-pyruvic transaminase activities. The HC diet increased the mRNA expression of key genes involved in lipid synthesis (DGAT, SREBP, FAS) in the fish fed the diet without MI supplementation. Dietary MI significantly under expressed fatty acid synthetase in fish fed the HC diets. Moreover, the mRNA expression of genes related to lipid catabolism (CPT, ATGL, PPAR-α) was significantly up-regulated with the increase of dietary MI levels despite dietary carbohydrate levels. The gene expressions of gluconeogenesis, glycolysis and MI biosynthesis were significantly down-regulated, while the expression of the pentose phosphate pathway was up-regulated with the increase of MI levels. This study indicates that HC diets can interrupt normal lipid metabolism and tend to form a fatty liver in fish. Dietary MI supplement can alleviate lipid accumulation in the liver by diverging some glucose metabolism into the pentose phosphate pathway and enhance the antioxidant capacity in O. niloticus.

Role of Inositols and Inositol Phosphates in Energy Metabolism

Recently, inositols, especially myo-inositol and inositol hexakisphosphate, also known as phytic acid or IP6, with their biological activities received much attention for their role in multiple health beneficial effects. Although their roles in cancer treatment and prevention have been extensively reported, interestingly, they may also have distinctive properties in energy metabolism and metabolic disorders. We review inositols and inositol phosphate metabolism in mammalian cells to establish their biological activities and highlight their potential roles in energy metabolism. These molecules are known to decrease insulin resistance, increase insulin sensitivity, and have diverse properties with importance from cell signaling to metabolism. Evidence showed that inositol phosphates might enhance the browning of white adipocytes and directly improve insulin sensitivity through adipocytes. In addition, inositol pyrophosphates containing high-energy phosphate bonds are considered in increasing cellular energetics. Despite all recent advances, many aspects of the bioactivity of inositol phosphates are still not clear, especially their effects on insulin resistance and alteration of metabolism, so more research is needed.

Altered Ovarian Inositol Ratios May Account for Pathological Steroidogenesis in PCOS

The presence of abnormal ovarian ratios of myo-inositol (MI) to D-chiro-inositol (DCI) is a recurrent feature in PCOS. Available evidence suggests that MI and DCI may modulate steroid biosynthesis, likely in an opposite manner. Specifically, MI seems to induce estrogen production, while DCI has a role in the synthesis of androgens. Elevated insulin levels, generally associated with PCOS, alter the physiological MI/DCI ratio, increasing MI-to-DCI conversion through activation of a specific epimerase enzyme. DCI directly increases testosterone biosynthesis in thecal cells and reduces its conversion to estradiol by downregulating aromatase enzyme in granulosa cells. This manuscript reviews the literature that supports the connection between altered MI/DCI ratios and pathological steroidogenesis observed in PCOS women. Furthermore, it discusses the application of inositol-based treatment protocols in managing PCOS symptoms and improving the quality of patients' life.

Current and experimental drug therapy for the treatment of polycystic ovarian syndrome

INTRODUCTION

Polycystic ovary syndrome (PCOS) is an endocrine disorder that affects 8-13% of reproductive-age women. Irregular periods, hirsutism, or infertility are the most common clinical presentations of patients affected by PCOS. This syndrome is also linked to metabolic abnormalities such as type 2 diabetes, insulin resistance and obesity. The optimal therapeutic approach is still unknown.

AREAS COVERED

This narrative review offers an overview of the literature on current and experimental pharmacological options for treating PCOS and highlights ongoing clinical trials. Several electronic databases were searched and current research registers were analyzed to the present year. The papers selected for this review were critically analyzed, and all data available were summarized, organized, and explored to derive key information.

EXPERT OPINION

The main goal of PCOS treatment is to obtain a metabolic and hormonal balance. Optimal PCOS therapy should be direct to the reproductive abnormalities and the entire spectrum of endocrine and metabolic complications that appear to have a long-term negative impact on PCOS patient health, as in post-menopausal period. The discovery of new mechanisms in PCOS pathogenesis will offer the possibility of testing new drug classes.

Metabolomics analyses to characterize metabolic alterations in Korean native calves by oral vitamin A supplementation

Previous studies have reported that vitamin A administration in the birth stage of calves could promote preadipocyte and muscle development. However, the metabolic change after vitamin A administration remains unknown. Thus, the objective of this study was to perform metabonomics analyses to investigate the effect of vitamin A in Korean native calves. Ten newborn calves (initial average body weight: 30.4 kg [SD 2.20]) were randomly divided into two groups treated with or without vitamin A supplementation (0 IU vs. 25,000 IU vitamin A/day) for two months until weaning. Metabolic changes in the serum and longissimus dorsi muscle of calves were investigated using GC-TOF-MS and multivariate statistical analysis. As a result, ten metabolic parameters in the serum and seven metabolic parameters in the longissimus dorsi muscle were down-regulated in the vitamin A treatment group compared to those in the control group (VIP value > 1.0, p < 0.05). Both serum and longissimus dorsi muscle showed lower levels of cholesterol and myo-inositol in the vitamin A treatment group than in the control group (p < 0.05). These results indicate that vitamin A supplementation in the early growth period of calf could maintain the preadipocyte status, which can contribute to future adipogenesis in the intramuscular fat production of Korean native cattle.

New Frontiers for the Use of IP6 and Inositol Combination in Treating Diabetes Mellitus: A Review

Inositol, or myo-inositol, and associated analog molecules, including myo-inositol hexakisphosphate, are known to possess beneficial biomedical properties and are now being widely studied. The impact of these compounds in improving diabetic indices is significant, especially in light of the high cost of treating diabetes mellitus and associated disorders globally. It is theorized that, within ten years, the global population of people with the disease will reach 578 million individuals, with the cost of care projected to be approximately 2.5 trillion dollars. Natural alternatives to pharmaceuticals are being sought, and this has led to studies involving inositol, and myo-inositol-hexakisphosphate, also referred to as IP6. It has been reported that IP6 can improve diabetic indices and regulate the activities of some metabolic enzymes involved in lipid and carbohydrate metabolism. Current research activities have been focusing on the mechanisms of action of inositol and IP6 in the amelioration of the indices of diabetes mellitus. We demonstrated that an IP6 and inositol combination supplement may regulate insulin secretion, modulate serum leptin concentrations, food intake, and associated weight gain, which may be beneficial in both prediabetic and diabetic states. The supplement attenuates vascular damage by reducing red cell distribution width. Serum HDL is increased while serum triglycerides tend to decrease with consumption of the combination supplement, perhaps due to the modulation of lipogenesis involving reduced serum lipase activity. We also noted increased fecal lipid output following combination supplement consumption. Importantly, liver function was found to be preserved. Concurrently, serum reactive oxygen species production was reduced, indicating that inositol and IP6 supplement consumption may reduce free radical damage to tissues and organs as well as serum lipids and blood glucose by preserving liver function. This review provides an overview of the findings associated with inositol and IP6 supplementation in the effective treatment of diabetes with a view to proposing the potential mechanisms of action.

Experts' opinion on inositols in treating polycystic ovary syndrome and non-insulin dependent diabetes mellitus: a further help for human reproduction and beyond

Introduction: This Experts' opinion provides an updated scientific support to gynecologists, obstetricians, endocrinologists, nutritionists, neurologists and general practitioners on the use of Inositols in the therapy of Polycystic Ovary Syndrome (PCOS) and non-insulin dependent (type 2) diabetes mellitus (NIDDM).Areas covered: This paper summarizes the physiology of Myo-Inositol (MI) and D-Chiro-Inositol (DCI), two important molecules present in human organisms, and their therapeutic role, also for treating infertility. Some deep differences between the physiological functions of MI and DCI, as well as their safety and intestinal absorption are discussed. Updates include new evidence on the efficacy exerted in PCOS by the 40:1 MI/DCI ratio, and the innovative approach based on alpha-lactalbumin to overcome the decreased therapeutic efficacy of Inositols in some patients.Expert opinion: The evidence suggests that MI, alone or with DCI in the 40:1 ratio, offers a promising treatment for PCOS and NIDDM. However, additional studies need to evaluate some still unresolved issues, such as the best MI/DCI ratio for treating NIDDM, the potential cost-effectiveness of reduced gonadotropins administration in IVF due to MI treatment, or the benefit of MI supplementation in ovulation induction with clomiphene citrate in PCOS patients.

Myo-inositol: its metabolism and potential implications for poultry nutrition-a review

Myo-inositol (MI) has gained relevance in physiology research during the last decade. As a constituent of animal cells, MI was proven to be crucial in several metabolic and regulatory processes. Myo-inositol is involved in lipid signaling, osmolarity, glucose, and insulin metabolism. In humans and rodents, dietary MI was assessed to be important for health so that MI supplementation appeared to be a valuable alternative for treatment of several diseases as well as for improvements in metabolic performance. In poultry, there is a lack of evidence not only related to specific species-linked metabolic processes but also about the effects of dietary MI on performance and health. This review intends to provide information about the meaning of dietary MI in animal metabolism as well as to discuss potential implications of dietary MI in poultry health and performance with the aim to identify open questions in poultry research.

Dietary phytase and myo-inositol supplementation are associated with distinct plasma metabolome profile in broiler chickens

Phytase enzyme is used as a dietary supplement in broiler nutrition to improve phosphorous bioavailability. Phytase deliberates phosphate groups from phytic acid and produces myo-inositol after total dephosphorylation. Myo-inositol is a bioactive compound having beneficial modulatory effects on metabolism in humans. However, it is not well understood if and how phytic acid degradation products, particularly myo-inositol, can modulate metabolism in broiler chicken. The purpose of this study was to investigate effects of dietary supplements of phytase and myo-inositol on the blood plasma metabolome profile of broiler chickens. Broilers were provided a nutrient-adequate control diet or the same diet supplemented with either 3.5 g myo-inositol or 500, 1500 or 3000 units of phytase, per kilogram of feed (grower diet). Broilers were group-housed in floor pens (eight pens per diet) and provided one of the treatment diets for 22 days. Then, blood was collected from one bird per pen, resulting in eight replicated measurements per diet. A targeted metabolomics approach was applied to the heparin plasma. Body weight of the birds was not significantly affected by the treatments. Plasma myo-inositol concentrations were significantly increased by myo-inositol supplementation and phytase supplementation at 500 and 1500 units/kg. Metabolites generally affected by phytase supplementation belonged to the groups of acyl-carnitines, phosphatidylcholines, sphingomyelins, lysophosphatidylcholine, biogenic amines and amino acids. Compared to the control diet, phytase supplements had significantly higher plasma concentrations of kynurenine and creatinine, but lower concentrations of histamine and cis-4-hydroxyproline. Myo-inositol supplementation significantly increased plasma concentrations of dopamine and serotonine. While some metabolites were similarly affected by myo-inositol and phytase supplementation, others were distinctly differently affected. We conclude that myo-inositol, either as a directly added supplement or indirectly released from phytate upon phytase supplementation, can affect specific metabolic pathways. Additional effects found on phytase supplementation may be related to intermediary phytate degradation products. Results are indicative for innovative hypothesis to be tested in future experiments, for instance, with regard to relationships between phytase or myo-inositol supplements and bird immunity or behaviour.

IRS-1 targets TAZ to inhibit adipogenesis of rat bone marrow mesenchymal stem cells through PI3K-Akt and MEK-ERK pathways

Gene modification of mesenchymal stem cells (MSCs) offers a promising approach for clinical stem cell therapy. Transcriptional co-activator with PDZ-binding motif (TAZ) plays a vital role in MSCs' differentiation. We aim to explore the interaction of insulin receptor substrate-1 (IRS-1) with TAZ to regulate MSCs' adipogenesis in this study. Initially, IRS-1 and TAZ followed similar decreasing expression pattern at the early stage of adipogenesis. And, overexpression of IRS-1 decreased the CCAAT/enhancer binding protein β (C/EBPβ) and peroxi-some proliferator-activated receptor gamma (PPARγ) expression with TAZ upregulation. Accordingly, knockdown of IRS-1 induced the upexpression of C/EBPβ and PPARγ with TAZ downregulation. Indeed, IRS-1 targeted TAZ to downregulate the C/EBPβ and PPARγ expression, while knockdown of TAZ attenuated the IRS-1 inhibited adipogenesis. Furthermore, both LY294002 (the PI3K-Akt inhibitor) and U0126 (the MEK-ERK inhibitor) blocked the regulation of IRS-1 on TAZ during adipogenesis. Additionally, IRS-1 and TAZ influenced the cell proliferation in the above process. Taken together, this study suggests for the first time that IRS-1 is a key regulator of the MSCs' adipogenesis and may serve as a potential therapeutic target for differential alterations in bone marrow.

Lack of effects of myo-inositol on metabolism of primary rat adipocytes

Myo-inositol is a ubiquitous cyclitol, has an important regulatory role, and its intracellular depletion is associated with pathological changes. Effects of myo-inositol on adipose tissue are poorly elucidated. In this report, short-term influence of 20, 100, and 500 µM myo-inositol on metabolism of the isolated rat adipocytes was studied. Cells were incubated for 90 min with glucose and insulin with or without myo-inositol and glucose conversion to lipids and lactate release were measured. Moreover, effects of myo-inositol on lipolysis and on the antilipolytic action of insulin were also studied. It was demonstrated that lipogenesis and lactate release were unchanged by myo-inositol. Moreover, lipolytic response to epinephrine and dibutyryl-cAMP was also unchanged. Myo-inositol was also found to be without influence on the antilipolytic action of insulin. Results of this study show that metabolism of the isolated rat adipocytes is not affected by short-term exposure of these cells to myo-inositol.

Intake of phytic acid and myo-inositol lowers hepatic lipogenic gene expression and modulates gut microbiota in rats fed a high-sucrose diet

Dietary phytic acid (PA) was recently reported by our group to suppress hepatic lipogenic gene expression and modulate gut microbiota in rats fed a high-sucrose (HSC) diet. The present study aimed to investigate whether the modulatory effects of PA depend on the dietary carbohydrate source and are attributed to the myo-inositol (MI) ring of PA. Male Sprague-Dawley rats were fed an HSC or a high-starch (HSR) diet with or without 1.02% sodium PA for 12 days. Subsequently, the rats were fed the HSC diet, the HSC diet containing 1.02% sodium PA or an HSC diet containing 0.2% MI for 12 days. The HSC diet significantly increased the hepatic triglyceride (TG) concentration as well as the activity and expression of hepatic lipogenic enzymes compared with the HSR diet. The increases were generally suppressed by dietary PA with a concomitant increase in the fecal and cecal ratios of Lactobacillus spp. In rats fed the HSR diet, PA intake did not substantially affect the factors associated with hepatic lipid metabolism or gut microbiota composition. The effects of MI intake were similar to that of PA intake on hepatic lipogenesis and gut microbiota in rats fed the HSC diet. These results suggest that dietary PA downregulates hepatic lipogenic gene expression and modulates gut microbiota composition in rats fed an HSC diet but not in rats fed an HSR diet. The MI ring of PA may be responsible for the effects of PA intake on hepatic lipogenic gene expression and gut microbiota.

Inositol hexaphosphate hydrolysate competitively binds to AKT to inhibit the proliferation of colon carcinoma

Phytate, myto-inositol 1,2,3,4,5,6 hexaphosphate (IP6), is recognized as an anti-nutrition phytochemical for decades. Recently, numerous studies have indicated that IP6 and its hydrolysates could suppress colon oncogenesis. However, very little is known concerning the mechanism of IP6 hydrolysates in regulating colon oncogenesis. The aim of the present study was to identify the underlying relationship between IP6 hydrolysates and colon cancer. Three types of human colorectal cancer cells were utilized in the present study. The proliferation inhibition and migration assays were employed to reveal that IP6 hydrolysates inhibited the proliferation of SW620 cells. Real-time PCR, cell-based ELISA and the AKT inhibitor assay were utilized to reveal that 20 and 30% degree of hydrolysis hydrolysates of IP6 inhibited SW620 cell growth by inhibiting the activation of AKT protein. The docking simulation study revealed that IP4 and IP5 could inhibit the activation of AKT by binding to PIP3 receptor. Collectively, our results indicated that the IP6 hydrolysates inhibit SW620 cell proliferation; IP4 and IP5, the probable primary constituents of the 20-30% degree of hydrolysis hydrolysates of IP6, inhibited the proliferation of SW620 cells by competitively inhibiting the AKT protein.

Epimedium koreanum Nakai and its main constituent icariin suppress lipid accumulation during adipocyte differentiation of 3T3-L1 preadipocytes

Obesity is associated with a number of metabolic abnormalities such as type 2 diabetes and has become a major health problem worldwide. In the present study, we investigated the effects of Epimedium koreanum Nakai (Herba Epimedii, HE) and its main constituent icariin on the adipocyte differentiation in 3T3-L1 preadipocytes. HE extract and icariin significantly reduced lipid accumulation and suppressed the expressions of PPARγ, C/EBPα, and SREBP-1c in 3T3-L1 adipocytes. They also inhibited fatty acid synthase (FAS), acyl-Co A synthase (ACS1), and perilipin. Moreover, HE extract and icariin markedly increased the phosphorylation of AMPK. These results indicated that HE extract and icariin can inhibit the adipocyte differentiation through downregulation of the adipogenic transcription factors, suggesting that HE containing icariin may be used as a potential therapeutic agent in the treatment and prevention of obesity.

The effect of combined inositol hexakisphosphate and inositol supplement in streptozotocin-induced type 2 diabetic rats

Inositol hexakisphosphate (IP6) and inositol both regulate insulin secretion, but their combined use in the management of diabetes deserves investigation. The combined effects of IP6 and inositol supplementation were investigated in streptozotocin-induced type 2 diabetic rats. The following groups of rats were studied for 8 weeks: non-diabetic control, non-diabetic high-fat diet control, diabetic untreated, diabetic rats treated with the combination of IP6 and inositol (650 mg/kg bw) and diabetic rats treated with glibenclamide (10 mg/kg bw). High-fat diet and streptozotocin were used to induce type 2 diabetes mellitus in Sprague-Dawley rats. Body weight, blood glucose, glycated haemoglobin, insulin, serum leptin, HOMA-insulin resistance scores, intestinal amylase activity, serum and faecal lipids and food and fluid consumption were measured. Treatment with the combination significantly reduced blood glucose (306 ± 53 mg/dl) and insulin resistance score (1.93 ± 0.45) compared with diabetic controls (522 ± 24 mg/dl and 5.1 ± 0.69 respectively). Serum leptin (2.8 ± 0.6 ng/dl) and faecal triglycerides (108 ± 8 mg/dl) were significantly increased in rats treated with the combination compared with the diabetic control (1.8 ± 0.06 ng/dl and 86 ± 4 mg/dl). Serum triglyceride (47 ± 5.1 mg/dl), total cholesterol (98 ± 3.2 mg/dl) and food intake (26 ± 0.3 g) were significantly reduced by 45%, 25% and 25%, respectively, in rats treated with the combination compared with the diabetic control. Inositol and IP6 combined supplementation may be effective in the management of type 2 diabetes mellitus and related metabolic disorders by regulating some aspects of lipid and carbohydrate metabolism.

Conundrum of IP6

Here are comments on the recent paper on the determination of inositol hexaphosphate (IP6) in human plasma and on its efficacy.