Curcumin ameliorates autoimmune diabetes. Evidence in accelerated murine models of type 1 diabetes

Shellac and locust bean gum coacervated curcumin, epigallocatechin gallate nanoparticle ameliorates diabetic nephropathy in a streptozotocin-induced mouse model

Curcumin and epigallocatechin gallate have the disadvantage of low aqueous solubility and first-pass metabolism, resulting in limited bioavailability. This work aimed to enhance oral bioavailability by forming gastric pH-stable shellac nanoparticles containing curcumin and epigallocatechin gallate using locust bean gum by anti-solvent precipitation (CESL-NP). The nanoparticles were characterized by their particle size, morphology, zeta potential, gastric pH stability, release profile, drug loading, and entrapment efficiency. The findings showed that a network of hydrolyzed shellac, locust bean gum, curcumin, and epigallocatechin gallate successfully entrapped individual particles inside a complex system. The morphological investigation of the CESL-NP formulation using FESEM, TEM, and AFM revealed the presence of spherical particles. FTIR, DSC, and XRD analysis revealed that curcumin and epigallocatechin gallate were amorphous due to their bond interactions with the matrix. Streptozotocin-treated mice, upon treatment with CESL-NP, showed kidney and pancreatic improvements with normalized kidney hypertrophy index and histopathology, maintained biochemical parameters, increased beta cell count, and a 38.68-fold higher blood glucose level inhibition were observed when compared to free-(CUR + EGCG). This research affirms that the shellac-locust bean gum complex shows potential for the sustained oral delivery of curcumin and epigallocatechin gallate, specifically for treating diabetic nephropathy.

Comprehensive and critical view on the anti-inflammatory and immunomodulatory role of natural phenolic antioxidants

The immune response encompasses innate and adaptive immunity, each with distinct and specific activities. The innate immune system is constituted by phagocytic cells, macrophages, monocytes and neutrophils, the cascade system, and different classes of receptors such as toll-like receptors that are exploited by the innate immune cells. The adaptive immune system is antigen-specific, encompassing memory lymphocytes and the corresponding specific receptors. Inflammation is understood as an activation of different signaling pathways such as toll-like receptors or nuclear factor kappa-light-chain-enhancer of activated B cells, with an increase in nitric oxide, inflammatory cytokines and chemokines. Increased oxidative stress has been identified as main source of chronic inflammation. Phenolic antioxidants modulate the activities of lymphocytes and macrophages by impacting cytokines and nitric oxide release, exerting anti-inflammatory effect. The nuclear-factor kappa-light-chain-enhancer of activated B cells signaling pathway and the mitogen-activated protein kinase pathway are targeted, alongside an increase in nuclear factor erythroid 2-related factor mediated antioxidant response, triggering the activity of antioxidant enzymes. The inhibitive potential on phospholipase A2, cyclooxygenase and lipoxygenase in the arachidonic acid pathway, and the subsequent reduction in prostaglandin and leukotriene generation, reveals the potential of phenolics as inflammation antagonists. The immunomodulative potential encompasses the capacity to interfere with proinflammatory cytokine synthesis and with the expression of the corresponding genes. A diet rich in antioxidants can result in prevention of inflammation-related pathologies. More investigations are necessary to establish the role of these antioxidants in therapy. The appropriate delivery system and the prooxidant effects exhibited at large doses, or in the presence of heavy metal cations should be regarded.

PPARs at the crossroads of T cell differentiation and type 1 diabetes

T-cell-mediated autoimmune type 1 diabetes (T1D) is characterized by the immune-mediated destruction of pancreatic beta cells (β-cells). The increasing prevalence of T1D poses significant challenges to the healthcare system, particularly in countries with struggling economies. This review paper highlights the multifaceted roles of Peroxisome Proliferator-Activated Receptors (PPARs) in the context of T1D, shedding light on their potential as regulators of immune responses and β-cell biology. Recent research has elucidated the intricate interplay between CD4+ T cell subsets, such as Tregs and Th17, in developing autoimmune diseases like T1D. Th17 cells drive inflammation, while Tregs exert immunosuppressive functions, highlighting the delicate balance crucial for immune homeostasis. Immunotherapy has shown promise in reinstating self-tolerance and restricting the destruction of autoimmune responses, but further investigations are required to refine these therapeutic strategies. Intriguingly, PPARs, initially recognized for their role in lipid metabolism, have emerged as potent modulators of inflammation in autoimmune diseases, particularly in T1D. Although evidence suggests that PPARs affect the β-cell function, their influence on T-cell responses and their potential impact on T1D remains largely unexplored. It was noted that PPARα is involved in restricting the transcription of IL17A and enhancing the expression of Foxp3 by minimizing its proteasomal degradation. Thus, antagonizing PPARs may exert beneficial effects in regulating the differentiation of CD4+ T cells and preventing T1D. Therefore, this review advocates for comprehensive investigations to delineate the precise roles of PPARs in T1D pathogenesis, offering innovative therapeutic avenues that target both the immune system and pancreatic function. This review paper seeks to bridge the knowledge gap between PPARs, immune responses, and T1D, providing insights that may revolutionize the treatment landscape for this autoimmune disorder. Moreover, further studies involving PPAR agonists in non-obese diabetic (NOD) mice hold promise for developing novel T1D therapies.

Curcumin alleviates spleen immunotoxicity induced by decabrominated diphenyl ethers (BDE-209) by improving immune function and inhibiting inflammation and apoptosis in broilers

This study was conducted to assess the mitigating effects of curcumin (Cur) on immunotoxicity in the spleen of broilers induced by the polybrominated diphenyl ether BDE-209. Eighty one-day-old broilers were allocated to the following four groups: control group, BDE-209 (0.4 g/kg) group, BDE-209 (0.4 g/kg) + Cur (0.3 mg/kg) group, and Cur (0.3 mg/kg) group. Growth performance, immunological function, inflammation, and apoptosis were assessed after 42 days of treatment. The findings demonstrate that firstly, Cur restored spleen damage caused by BDE-209 by increasing body weight, decreasing feed-to-gain ratio, correcting the spleen index, and improving the histopathological structure of the spleen. Secondly, Cur relieved BDE-209-induced immunosuppression by increasing the levels of the immunoglobulins IgG, IgM, and IgA in the serum, as well as the levels of white blood cells and lymphocytes. The levels at which GATA binding protein 3, T-box expressed in T cells, interferon-γ, and interleukin (IL)- 4 are expressed were controlled. The ratio of T helper (Th) type 1 (Th1) to Th2 cells in the spleen of broilers was also controlled. Thirdly, Cur reduced the expression of Toll like receptor (TLR) 2, TLR4, nuclear factor (NF)-κB, IL-8, IL-6, and IL-1β, which alleviated BDE-209-induced inflammation in broilers. Cur reduced BDE-209-induced apoptosis by increasing the expression of the bcl-2 protein, decreasing the expression of cleaved caspase-3 and bax proteins, decreasing the bax/bcl-2 protein ratio, and decreasing the mean optical density of TUNEL. These results suggest that Cur protects broiler spleens from BDE-209-induced immunotoxicity via modulating humoral immunity, the equilibrium between Th1 and Th2 cells, the TLRs/NF-κB inflammatory pathway, and the apoptotic pathway.

The Anti-Inflammatory and Immunomodulatory Activities of Natural Products to Control Autoimmune Inflammation

Inflammation is an integral part of autoimmune diseases, which are caused by dysregulation of the immune system. This dysregulation involves an imbalance between pro-inflammatory versus anti-inflammatory mediators. These mediators include various cytokines and chemokines; defined subsets of T helper/T regulatory cells, M1/M2 macrophages, activating/tolerogenic dendritic cells, and antibody-producing/regulatory B cells. Despite the availability of many anti-inflammatory/immunomodulatory drugs, the severe adverse reactions associated with their long-term use and often their high costs are impediments in effectively controlling the disease process. Accordingly, suitable alternatives are being sought for these conventional drugs. Natural products offer promising adjuncts/alternatives in this regard. The availability of specific compounds isolated from dietary/medicinal plant extracts have permitted rigorous studies on their disease-modulating activities and the mechanisms involved therein. Here, we describe the basic characteristics, mechanisms of action, and preventive/therapeutic applications of 5 well-characterized natural product compounds (Resveratrol, Curcumin, Boswellic acids, Epigallocatechin-3-gallate, and Triptolide). These compounds have been tested extensively in animal models of autoimmunity as well as in limited clinical trials in patients having the corresponding diseases. We have focused our description on predominantly T cell-mediated diseases, such as rheumatoid arthritis, multiple sclerosis, Type 1 diabetes, ulcerative colitis, and psoriasis.

Compound A attenuates proinflammatory cytokine-induced endoplasmic reticulum stress in beta cells and displays beneficial therapeutic effects in a mouse model of autoimmune diabetes

Type 1 diabetes (T1D) is characterized by an immune-mediated progressive destruction of the insulin-producing β-cells. Proinflammatory cytokines trigger endoplasmic reticulum (ER) stress and subsequent insulin secretory deficiency in cultured β-cells, mimicking the islet microenvironment in T1D. β-cells undergo physiologic ER stress due to the high rate of insulin production and secretion under stimulated conditions. Severe and uncompensated ER stress in β-cells is induced by several pathological mechanisms before onset and during T1D. We previously described that the small drug Compound A (CpdA), a selective glucocorticoid receptor (GR/NR3C1, nuclear receptor subfamily 3, group C, member 1) ligand with demonstrated inflammation-suppressive activity in vivo, is an effective modulator of effector T and dendritic cells and of macrophages, yet, in a GR-independent manner. Here, we focus on CpdA's therapeutic potential in T1D cellular and animal models. We demonstrate that CpdA improves the unfolded protein response (UPR) by attenuating ER stress and favoring the survival and function of β-cells exposed to an environment of proinflammatory cytokines. CpdA administration to NODscid mice adoptively transferred with diabetogenic splenocytes (from diabetic NOD mice) led to a delay of disease onset and reduction of diabetes incidence. Histological analysis of the pancreas showed a reduction in islet leukocyte infiltration (insulitis) and preservation of insulin expression in CpdA-treated normoglycemic mice in comparison with control group. These new findings together with our previous reports justify further studies on the administration of this small molecule as a novel therapeutic strategy with dual targets (effector immune and β-cells) during autoimmune diabetes.

Therapeutic implications of glucose transporters (GLUT) in cerebral ischemia

Cerebral ischemia is a leading cause of death in the globe, with a large societal cost. Deprivation of blood flow, together with consequent glucose and oxygen shortage, activates a variety of pathways that result in permanent brain damage. As a result, ischemia raises energy demand, which is linked to significant alterations in brain energy metabolism. Even at the low glucose levels reported in plasma during ischemia, glucose transport activity may adjust to assure the supply of glucose to maintain normal cellular function. Glucose transporters in the brain are divided into two groups: sodium-independent glucose transporters (GLUTs) and sodium-dependent glucose cotransporters (SGLTs).This review assess the GLUT structure, expression, regulation, pathobiology of GLUT in cerebral ischemia and regulators of GLUT and it also provides the synopsis of the literature exploring the relationship between GLUT and the various downstream signalling pathways for e.g., AMP-activated protein kinase (AMPK), CREB (cAMP response element-binding protein), Hypoxia-inducible factor 1 (HIF)-1, Phosphatidylinositol 3-kinase (PI3-K), Mitogen-activated protein kinase (MAPK) and adenylate-uridylate-rich elements (AREs). Therefore, the aim of the present review was to elaborate the therapeutic implications of GLUT in the cerebral ischemia.

The Role of Bioactive Compounds in Natural Products Extracted from Plants in Cancer Treatment and Their Mechanisms Related to Anticancer Effects

Cancer is one of the greatest causes of death worldwide. With the development of surgery, radiotherapy, and medical agents, the outcomes of cancer patients have greatly improved. However, the underlying mechanisms of cancer are not yet fully understood. Recently, natural products have been proven to be beneficial for various conditions and have played important roles in the development of novel therapies. A substantial amount of evidence indicates that bioactive compounds could improve the outcomes of cancer patients via various pathways, such as endoplasmic reticulum stress, epigenetic modification, and modulation of oxidative stress. Here, we review the current evidence of bioactive compounds in natural products for the treatment of cancer and summarize the underlying mechanisms in this pathological process.

Pharmacological Mechanisms and Clinical Applications of Curcumin: Update

Curcumin, a well-known hydrophobic polyphenol extracted from the rhizomes of turmeric (Curcuma longa L.), has attracted great interest in the last ten years due to its multiple pharmacological activities. A growing body of evidence has manifested that curcumin has extensive pharmacological activities including anti-inflammatory, anti-oxygenation, lipid regulation, antiviral, and anticancer with hypotoxicity and minor adverse reactions. However, the disadvantages of low bioavailability, short half-life in plasma, low drug concentration in blood, and poor oral absorption severely limited the clinical application of curcumin. Pharmaceutical researchers have carried out plenty of dosage form transformations to improve the druggability of curcumin and have achieved remarkable results. Therefore, the objective of this review summarizes the pharmacological research progress, problems in clinical application and the improvement methods of curcumin's druggability. By reviewing the latest research progress of curcumin, we believe that curcumin has a broad clinical application prospect for its wide range of pharmacological activities with few side effects. The deficiencies of lower bioavailability of curcumin could be improved by dosage form transformation. However, curcumin in the clinical application still requires further study regarding the underlying mechanism and clinical trial verification.

New Developments in T Cell Immunometabolism and Therapeutic Implications for Type 1 Diabetes

Type 1 diabetes (T1D) is an autoimmune disease mediated by T cells and is becoming a serious public health threat. Despite the increasing incidence rate of T1D worldwide, our understanding of why T1D develops and how T cells lose their self-tolerance in this process remain limited. Recent advances in immunometabolism have shown that cellular metabolism plays a fundamental role in shaping T cell responses. T cell activation and proliferation are supported by metabolic reprogramming to meet the increased energy and biomass demand, and deregulation in immune metabolism can lead to autoimmune disorders. Specific metabolic pathways and factors have been investigated to rectify known deficiencies in several autoimmune diseases, including T1D. Most therapeutic strategies have concentrated on aerobic glycolysis to limit T cell responses, whereas glycolysis is the main metabolic pathway for T cell activation and proliferation. The use of metabolic inhibitors, especially glycolysis inhibitors may largely leave T cell function intact but primarily target those autoreactive T cells with hyperactivated metabolism. In this review, we provide an overview of metabolic reprogramming used by T cells, summarize the recent findings of key metabolic pathways and regulators modulating T cell homeostasis, differentiation, and function in the context of T1D, and discuss the opportunities for metabolic intervention to be employed to suppress autoreactive T cells and limit the progression of β-cell destruction.

Immunomodulatory Effects of Curcumin in Rheumatoid Arthritis: Evidence from Molecular Mechanisms to Clinical Outcomes

Rheumatoid arthritis (RA) is a chronic immune-mediated inflammatory disorder characterized by the destruction of the joint and bone resorption. The production of pro-inflammatory cytokines and chemokines, dysregulated functions of three important subtypes of T helper (T_H) cells including T_H1, T_H17, and regulator T (Treg) cells are major causes of the initiation and development of RA. Moreover, B cells as a source of the production of several autoantibodies play key roles in the pathogenesis of RA. The last decades have seen increasingly rapid advances in the field of immunopharmacology using natural origin compounds for the management of various inflammatory diseases. Curcumin, a main active polyphenol compound isolated from turmeric, curcuma longa, possesses a wide range of pharmacologic properties for the treatment of several diseases. This review comprehensively will assess beneficial immunomodulatory effects of curcumin on the production of pro-inflammatory cytokines and also dysregulated functions of immune cells including T_H1, T_H17, Treg, and B cells in RA. We also seek the clinical efficacy of curcumin for the treatment of RA in several recent clinical trials. In conclusion, curcumin has been found to ameliorate RA complications through modulating inflammatory and autoreactive responses in immune cells and synovial fibroblast cells via inhibiting the expression or function of pro-inflammatory mediators, such as nuclear factor-κB (NF-κB), activated protein-1 (AP-1), and mitogen-activated protein kinases (MAPKs). Of note, curcumin treatment without any adverse effects can attenuate the clinical symptoms of RA patients and, therefore, has therapeutic potential for the treatment of the diseases.

Experimental and clinical reports on anti-inflammatory, antioxidant, and immunomodulatory effects of Curcuma longa and curcumin, an updated and comprehensive review

Curcuma longa (C. longa) or turmeric is a plant with a long history of use in traditional medicine, especially for treating inflammatory conditions C. longa and its main constituent, curcumin (CUR), showed various pharmacological effects such as antioxidant and anti-microbial properties. The updated knowledge of anti-inflammatory, antioxidant, and immunomodulatory effects of C. longa and CUR is provided in this review article. Pharmacological effects of C. longa, and CUR, including anti-inflammatory, antioxidant, and immunomodulatory properties, were searched using various databases and appropriate keywords until September 2020. Various studies showed anti-inflammatory effects of C. longa and CUR, including decreased white blood cell, neutrophil, and eosinophil numbers, and its protective effects on serum levels of inflammatory mediators such as phospholipase A2 and total protein in different inflammatory disorders. The antioxidant effects of C. longa and CUR were also reported in several studies. The plant extracts and CUR decreased malondialdehyde and nitric oxide levels but increased thiol, superoxide dismutase, and catalase levels in oxidative stress conditions. Treatment with C. longa and CUR also improved immunoglobulin E (Ig)E, pro-inflammatory cytokine interleukin 4 (IL)-4, transforming growth factor-beta, IL-17, interferon-gamma levels, and type 1/type 2 helper cells (Th1)/(Th2) ratio in conditions with disturbance in the immune system. Therefore C. longa and CUR showed anti-inflammatory, antioxidant, and immunomodulatory effects, indicating a potential therapeutic effect of the plant and its constituent, CUR, for treating of inflammatory, oxidative, and immune dysregulation disorders.

Immunomodulatory Effects and Mechanisms of Curcuma Species and Their Bioactive Compounds: A Review

Curcuma species (family: Zingiberaceae) are widely utilized in traditional medicine to treat diverse immune-related disorders. There have been many scientific studies on their immunomodulating effects to support their ethnopharmacological uses. In this review, the efficacy of six Curcuma species, namely, C. longa L., C. zanthorrhiza Roxb., C. mangga Valeton & Zijp, C. aeruginosa Roxb. C. zedoaria (Christm.) Roscoe, and C. amada Roxb., and their bioactive metabolites to modulate the immune system, their mechanistic effects, and their potential to be developed into effective and safe immunomodulatory agents are highlighted. Literature search has been carried out extensively to gather significant findings on immunomodulating activities of these plants. The immunomodulatory effects of Curcuma species were critically analyzed, and future research strategies and appropriate perspectives on the plants as source of new immunomodulators were discussed. Most of the pharmacological investigations to evaluate their immunomodulatory effects were in vivo and in vitro experiments on the crude extracts of the plants. The extracts were not chemically characterized or standardized. Of all the Curcuma species investigated, the immunomodulatory effects of C. longa were the most studied. Most of the bioactive metabolites responsible for the immunomodulating activities were not determined, and mechanistic studies to understand the underlying mechanisms were scanty. There are limited clinical studies to confirm their efficacy in human. Of all the bioactive metabolites, only curcumin is undergoing extensive clinical trials based on its anti-inflammatory properties and main use as an adjuvant for the treatment of cancer. More in-depth studies to understand the underlying mechanisms using experimental in vivo animal models of immune-related disorders and elaborate bioavailability, preclinical pharmacokinetics, and toxicity studies are required before clinical trials can be pursued for development into immunomodulatory agents.

Dietary and Protective Factors to Halt or Mitigate Progression of Autoimmunity, COVID-19 and Its Associated Metabolic Diseases

COVID-19 is without any doubt the worst pandemic we have faced since the H1N1 virus outbreak. Even if vaccination against SARS-CoV-2 infection is becoming increasingly available, a more feasible approach for COVID-19 prevention and therapy is still needed. Evidence of a pathological link between metabolic diseases and severe forms of COVID-19 has stimulated critical reflection and new considerations. In particular, an abnormal immune response observed in certain patients with SARS-CoV-2 infection suggested possible common predisposing risk factors with autoimmune diseases such as Type 1 Diabetes (T1D). Correct supplementation with dietary factors may be key to preventing and counteracting both the underlying metabolic impairment and the complications of COVID-19. A set of agents may inhibit the cytokine storm and hypercoagulability that characterize severe COVID-19 infection: vitamin D3, omega-3 polyunsaturated fatty acids, polyphenols like pterostilbene, polydatin and honokiol, which can activate anti-inflammatory and antioxidant sirtuins pathways, quercetin, vitamin C, zinc, melatonin, lactoferrin and glutathione. These agents could be highly beneficial for subjects who have altered immune responses. In this review, we discuss the antiviral and metabolic effects of these dietary factors and propose their combination for potential applications in the prevention and treatment of COVID-19. Rigorous studies will be fundamental for validating preventive and therapeutic protocols that could be of assistance to mitigate disease progression following SARS-CoV-2 infection.

Natural Insulin Sensitizers for the Management of Diabetes Mellitus: A Review of Possible Molecular Mechanisms

Diabetes mellitus is a growing health challenge globally which is increasing in epidemic proportion. Naturally occurring pharmacological agents are more likely to provide beneficial therapeutic effects without undesirable side effects compared to the synthetic agents. There is a growing evidence that some naturally occurring pharmacological agents derived from plants have potential antihyperglycemic effects. In this study, we have reviewed the molecular mechanism behind potential hypoglycemic properties of four well-known herbal-based agents, namely, ginger, curcumin, garlic, and cinnamon. Also, we present the related clinical data confirming experimental results aiming to develop novel therapeutic strategies based on these herbal agents potentially for the management of patients with diabetes.

The potential therapeutic effects of curcumin on pregnancy complications: Novel insights into reproductive medicine

Pregnancy complications including preeclampsia, preterm birth, intrauterine growth restriction, and gestational diabetes are the main adverse reproductive outcomes. Excessive inflammation and oxidative stress play crucial roles in the pathogenesis of pregnancy disorders. Curcumin, the main polyphenolic compound derived from Curcuma longa, is mainly known by its anti-inflammatory and antioxidant properties. There are in vitro and in vivo reports revealing the preventive and ameliorating effects of curcumin against pregnancy complications. Here, we aimed to seek mechanisms underlying the modulatory effects of curcumin on dysregulated inflammatory and oxidative responses in various pregnancy complications.

Curcumin and Photobiomodulation in Chronic Viral Hepatitis and Hepatocellular Carcinoma

Immune modulation is a very modern medical field for targeting viral infections. In the race to develop the best immune modulator against viruses, curcumin, as a natural product, is inexpensive, without side effects, and can stimulate very well certain areas of the human immune system. As a bright yellow component of turmeric spice, curcumin has been the subject of thousands of scientific and clinical studies in recent decades to prove its powerful antioxidant properties and anticancer effects. Curcumin has been shown to influence inter- and intracellular signaling pathways, with direct effects on gene expression of the antioxidant proteins and those that regulate the immunity. Experimental studies have shown that curcumin modulates several enzyme systems, reduces nitrosative stress, increases the antioxidant capacity, and decreases the lipid peroxidation, protecting against fatty liver pathogenesis and fibrotic changes. Hepatitis B virus (HBV) affects millions of people worldwide, having sometimes a dramatic evolution to chronic aggressive infection, cirrhosis, and hepatocellular carcinoma. All up-to-date treatments are limited, there is still a gap in the scientific knowledge, and a sterilization cure may not yet be possible with the removal of both covalently closed circular DNA (cccDNA) and the embedded HBV DNA. With a maximum light absorption at 420 nm, the cytotoxicity of curcumin as photosensitizer could be expanded by the intravenous blue laser blood irradiation (IVBLBI) or photobiomodulation in patients with chronic hepatitis B infection, Hepatitis B e-antigen (HBeAg)-positive, noncirrhotic, but nonresponsive to classical therapy. Photobiomodulation increases DNA repair by the biosynthesis of complex molecules with antioxidant properties, the outset of repairing enzyme systems and new phospholipids for regenerating the cell membranes. UltraBioavailable Curcumin and blue laser photobiomodulation could suppress the virus and control better the disease by reducing inflammation/fibrosis and stopping the progression of chronic hepatitis, reversing fibrosis, and diminishing the progression of cirrhosis, and decreasing the incidence of hepatocellular carcinoma. Photodynamic therapy with blue light and curcumin opens new avenues for the effective prevention and cure of chronic liver infections and hepatocellular carcinoma. Blue laser light and UltraBioavailable Curcumin could be a new valuable alternative for medical applications in chronic B viral hepatitis and hepatocarcinoma, saving millions of lives.

Glucose transporters in brain in health and disease

Energy demand of neurons in brain that is covered by glucose supply from the blood is ensured by glucose transporters in capillaries and brain cells. In brain, the facilitative diffusion glucose transporters GLUT1-6 and GLUT8, and the Na⁺-d-glucose cotransporters SGLT1 are expressed. The glucose transporters mediate uptake of d-glucose across the blood-brain barrier and delivery of d-glucose to astrocytes and neurons. They are critically involved in regulatory adaptations to varying energy demands in response to differing neuronal activities and glucose supply. In this review, a comprehensive overview about verified and proposed roles of cerebral glucose transporters during health and diseases is presented. Our current knowledge is mainly based on experiments performed in rodents. First, the functional properties of human glucose transporters expressed in brain and their cerebral locations are described. Thereafter, proposed physiological functions of GLUT1, GLUT2, GLUT3, GLUT4, and SGLT1 for energy supply to neurons, glucose sensing, central regulation of glucohomeostasis, and feeding behavior are compiled, and their roles in learning and memory formation are discussed. In addition, diseases are described in which functional changes of cerebral glucose transporters are relevant. These are GLUT1 deficiency syndrome (GLUT1-SD), diabetes mellitus, Alzheimer’s disease (AD), stroke, and traumatic brain injury (TBI). GLUT1-SD is caused by defect mutations in GLUT1. Diabetes and AD are associated with changed expression of glucose transporters in brain, and transporter-related energy deficiency of neurons may contribute to pathogenesis of AD. Stroke and TBI are associated with changes of glucose transporter expression that influence clinical outcome.

Curcumin Attenuates Both Acute and Chronic Immune Nephritis

Curcumin is known to have immunomodulatory potential in addition to anti-oxidant, anti-inflammatory and anti-carcinogenic effects. The aim of the present study is to investigate the therapeutic effects of curcumin on immune-mediated renal disease in an anti-glomerular basement membrane (GBM) model (representing acute kidney Injury, AKI) and murine lupus model (representing chronic kidney disease, CKD). In the AKI model, female anti-GBM 129/svj mice were administered with curcumin right before disease induction. In the CKD model, female MRL.lpr mice at the age of 8-10 weeks old were treated with curcumin or placebo via oral gavage daily for two months. After treatment, serum autoantibody levels, splenomegaly and spleen cellularity were reduced in murine lupus. Collectively, curcumin ameliorated kidney disease in the two mouse models with either acute or chronic nephritis, as marked by reduced proteinuria, blood urea nitrogen, glomerulonephritis, crescent formation, tubule-interstitial disease, and renal infiltration by lymphocytes. In addition, curcumin treatment reduced activation of the NFkB, MAPK, AKT and pBAD pathways either systemically, or within the inflamed kidneys. These findings suggest that natural food supplements could become an alternative approach to ameliorating immune-mediated kidney diseases.

PPARs and the Development of Type 1 Diabetes

Peroxisome proliferator-activated receptors (PPARs) are a family of transcription factors with a key role in glucose and lipid metabolism. PPARs are expressed in many cell types including pancreatic beta cells and immune cells, where they regulate insulin secretion and T cell differentiation, respectively. Moreover, various PPAR agonists prevent diabetes in the non-obese diabetic (NOD) mouse model of type 1 diabetes. PPARs are thus of interest in type 1 diabetes (T1D) as they represent a novel approach targeting both the pancreas and the immune system. In this review, we examine the role of PPARs in immune responses and beta cell biology and their potential as targets for treatment of T1D.

Curcumin ameliorates gestational diabetes in mice partly through activating AMPK

CONTEXT

In vitro and in vivo research has shown that curcumin can alleviate diabetes and the relevant complications.

OBJECTIVE

To investigate the effect of curcumin on gestational diabetes (GD).

MATERIALS AND METHODS

C57 BL/KsJ^db/+(db/+) mice and C57 BL/KsJ^+/+ mice (10-12 weeks old) were divided into four groups (n = 15): normal pregnancy (C57 BL/KsJ^+/+), GD (C57 BL/KsJ^db/+), GD plus low dose curcumin (50 mg/kg, orally gavage every day) and GD plus high dose curcumin (100 mg/kg, orally gavage every day). The tolerance of glucose and insulin were measured on gestation day 10. Body weight at birth and litter size of offspring were investigated, and the expression of oxidative stress factors [thiobarbituric acid reactive substance (TBARS), glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT)] and AMP-activated protein kinase (AMPK), phospho-AMPK, histone deacetylases 4 (HDAC4), pHDAC4 and glucose-6-phosphatase (G6Pase) in the livers were analyzed by ELISA and Western blot on gestation day 20.

RESULTS

High dose curcumin could partly ameliorate the intolerance of glucose and insulin, and completely restore the litter size and the body weight of GD mice through decreased TBARS expression (p < 0.05) and increased GSH, SOD and CAT expression (p < 0.05). Enhanced AMPK activation, accompanied with decreased HDAC4 and G6Pase expression (p < 0.05) were partly contributed to the alleviation of GD mediated by curcumin.

CONCLUSIONS

Although further detailed mechanism needs to be deciphered, curcumin can be considered as an alternative treatment for gestational diabetes.

Molecular mechanisms of curcumin and its analogs in colon cancer prevention and treatment

Colorectal cancer remains to be the most prevalent malignancy in humans and 1.5 million men and women living in the United States are diagnosed with colorectal cancer, with a predicted 145,600 new cases to be diagnosed in 2019. Curcuminoids and its synthetic analogs are now of interest due to their bioactive attributes, especially their action as anticancer activity in various cancer cell line models. Several in vivo and in vitro studies have substantially proved their anticancer activities against colon cancer cell lines. Curcumin analogues like IND-4, FLLL, GO-Y030 and C086 have demonstrated to produce greater cytotoxicity when experimentally studied and study results from many have been suggested to be the same. Combination of curcumin with therapeutic cancer agents like tolfenamic acid, 5-fluorouracil, resveratrol and dasatinib showed improved cytotoxicity and chemotherapeutic effect. The results propose that employment of curcumin with novel drug delivery systems like liposome, micelles and nanoparticle have been performed which could improve the therapeutic efficacy against colon cancer. The present review highlights the mechanism of action, synergistic effect and novel delivery methods to improve the therapeutic potential of curcumin.

Histological evidence of chitosan-encapsulated curcumin suppresses heart and kidney damages on streptozotocin-induced type-1 diabetes in mice model

High blood glucose in diabetic patients often causes cardiovascular diseases (CVDs) that threats to human life. Curcumin (Cur) is known as an antioxidant agent, possesses anti-inflammatory activity, and prevents CVDs. However, the clinical application of curcumin was limited due to its low bioavailability. This study aimed to investigate the ameliorative effects of chitosan-encapsulated curcumin (CEC) on heart and kidney damages in streptozotocin-induced type-1 diabetes C57BL/6 mice model. The results showed that Cur- and CEC-treatments downregulated the blood sugar and total cholesterol level as well as enhanced insulin secretion. However, blood pressure, triglycerides content, and very low-density lipoprotein-cholesterol content were not changed. Histochemistry analysis revealed that both curcumin and chitosan-encapsulated curcumin ameliorated cell hypertrophy and nucleus enlargement in the left ventricular of heart and reduced fibrosis in the kidney, especially after the chitosan-encapsulated curcumin treatment. Our study suggested that chitosan can effectively enhance the protective effect of curcumin on the heart and kidney damages in type-1 diabetes mice model.

Liposomal Curcumin is Better than Curcumin to Alleviate Complications in Experimental Diabetic Mellitus

Curcumin (CC) is known to have anti-inflammatory and anti-oxidative properties and has already been tested for its efficiency in different diseases including diabetes mellitus (DM). New formulations and route administration were designed to obtain products with higher bioavailability. Our study aimed to test the effect of intraperitoneal (i.p.) administration of liposomal curcumin (lCC) as pre-treatment in streptozotocin(STZ)-induced DM in rats on oxidative stress, liver, and pancreatic functional parameters. Forty-two Wistar-Bratislava rats were randomly divided into six groups (seven animals/group): control (no diabetes), control-STZ (STZ-induced DM —60 mg/100g body weight a single dose intraperitoneal administration, and no CC pre-treatment), two groups with DM and CC pre-treatment (1mg/100g bw—STZ + CC1, 2 mg/100g bw—STZ + CC2), and two groups with DM and lCC pre-treatment (1 mg/100g bw—STZ + lCC1, 2 mg/100g bw—STZ + lCC1). Intraperitoneal administration of Curcumin in diabetic rats showed a significant reduction of nitric oxide, malondialdehyde, total oxidative stress, and catalase for both evaluated formulations (CC and lCC) compared to control group (p < 0.005), with higher efficacy of lCC formulation compared to CC solution (p < 0.002, excepting catalase for STZ + CC2vs. STZ + lCC1when p = 0.0845). The CC and lCC showed hepatoprotective and hypoglycemic effects, a decrease in oxidative stress and improvement in anti-oxidative capacity status against STZ-induced DM in rats (p < 0.002). The lCC also proved better efficacy on MMP-2, and -9 plasma levels as compared to CC (p < 0.003, excepting STZ + CC2 vs. STZ + lCC1 comparison with p = 0.0553). The lCC demonstrated significantly better efficacy as compared to curcumin solution on all serum levels of the investigated markers, sustaining its possible use as adjuvant therapy in DM.

The Lysine Demethylase KDM5B Regulates Islet Function and Glucose Homeostasis

AIMS

Posttranslational modifications of histones and transcription factors regulate gene expression and are implicated in beta-cell failure and diabetes. We have recently shown that preserving H3K27 and H3K4 methylation using the lysine demethylase inhibitor GSK-J4 reduces cytokine-induced destruction of beta-cells and improves beta-cell function. Here, we investigate the therapeutic potential of GSK-J4 to prevent diabetes development and examine the importance of H3K4 methylation for islet function.

MATERIALS AND METHODS

We used two mouse models of diabetes to investigate the therapeutic potential of GSK-J4. To clarify the importance of H3K4 methylation, we characterized a mouse strain with knockout (KO) of the H3K4 demethylase KDM5B.

RESULTS

GSK-J4 administration failed to prevent the development of experimental diabetes induced by multiple low-dose streptozotocin or adoptive transfer of splenocytes from acutely diabetic NOD to NODscid mice. KDM5B-KO mice were growth retarded with altered body composition, had low IGF-1 levels, and exhibited reduced insulin secretion. Interestingly, despite secreting less insulin, KDM5B-KO mice were able to maintain normoglycemia following oral glucose tolerance test, likely via improved insulin sensitivity, as suggested by insulin tolerance testing and phosphorylation of proteins belonging to the insulin signaling pathway. When challenged with high-fat diet, KDM5B-deficient mice displayed similar weight gain and insulin sensitivity as wild-type mice.

CONCLUSION

Our results show a novel role of KDM5B in metabolism, as KDM5B-KO mice display growth retardation and improved insulin sensitivity.

Macrophage plasticity, polarization and function in response to curcumin, a diet-derived polyphenol, as an immunomodulatory agent

Monocytes and macrophages are important cells of the innate immune system that have diverse functions, including defense against invading pathogens, removal of dead cells by phagocytosis, antigen presentation in the context of MHC class I and class II molecules, and production of various pro-inflammatory cytokines and chemokines such as IL-1β, IL-6, TNF-α and MCP-1. In addition, pro-inflammatory (M1) and anti-inflammatory (M2) macrophages clearly play important roles in the progression of several inflammatory diseases. Therefore, therapies that target macrophage polarization and function by either blocking their trafficking to sites of inflammation, or skewing M1 to M2 phenotype polarization may hold clinical promise in several inflammatory diseases. Dietary-derived polyphenols have potent natural anti-oxidative properties. Within this group of polyphenols, curcumin has been shown to suppress macrophage inflammatory responses. Curcumin significantly reduces co-stimulatory molecules and also inhibits MAPK activation and the translocation of NF-κB p65. Curcumin can also polarize/repolarize macrophages toward the M2 phenotype. Curcumin-treated macrophages have been shown to be highly efficient at antigen capture and endocytosis via the mannose receptor. These novel findings provide new perspectives for the understanding of the immunopharmacological role of curcumin, as well as its therapeutic potential for impacting macrophage polarization and function in the context of inflammation-related disease. However, the precise effects of curcumin on the migration, differentiation, polarization and immunostimulatory functions of macrophages remain unknown. Therefore, in this review, we summarized whether curcumin can influence macrophage polarization, surface molecule expression, cytokine and chemokine production and their underlying pathways in the prevention of inflammatory diseases.

Immunomodulators Inspired by Nature: A Review on Curcumin and Echinacea

The immune system is an efficient integrated network of cellular elements and chemicals developed to preserve the integrity of the organism against external insults and its correct functioning and balance are essential to avoid the occurrence of a great variety of disorders. To date, evidence from literature highlights an increase in immunological diseases and a great attention has been focused on the development of molecules able to modulate the immune response. There is an enormous global demand for new effective therapies and researchers are investigating new fields. One promising strategy is the use of herbal medicines as integrative, complementary and preventive therapy. The active components in medical plants have always been an important source of clinical therapeutics and the study of their molecular pharmacology is an enormous challenge since they offer a great chemical diversity with often multi-pharmacological activity. In this review, we mainly analysed the immunomodulatory/antinflammatory activity of Echinacea spp. and Curcuma longa, focusing on some issues of the phytochemical research and on new possible strategies to obtain novel agents to supplement the present therapies.

Sodium Butyrate Ameliorates Streptozotocin-Induced Type 1 Diabetes in Mice by Inhibiting the HMGB1 Expression

Type 1 diabetes (T1D) is an autoimmune disease characterized by the immune cell-mediated progressive destruction of pancreatic β-cells. High-mobility group box 1 protein (HMGB1) has been recognized as a potential immune mediator to enhance the development of T1D. So we speculated that HMGB1 inhibitors could have anti-diabetic effect. Sodium butyrate is a short fatty acid derivative possessing anti-inflammatory activity by inhibiting HMGB1. In the current study, we evaluated the effects of sodium butyrate in streptozotocin (STZ)-induced T1D mice model. Diabetes was induced by multiple low-dose injections of STZ (40 mg/kg/day for 5 consecutive days), and then sodium butyrate (500 mg/kg/day) was administered by intraperitoneal injection for 7 consecutive days after STZ treatment. Blood glucose, incidence of diabetes, body weight, pancreatic histopathology, the amounts of CD4+T cell subsets, IL-1β level in serum and pancreatic expressions levels of HMGB1, and NF-κB p65 protein were analyzed. The results showed that sodium butyrate treatment decreased blood glucose and serum IL-1β, improved the islet morphology and decreased inflammatory cell infiltration, restored the unbalanced Th1/Th2 ratio, and down-regulated Th17 to normal level. In addition, sodium butyrate treatment can inhibit the pancreatic HMGB1 and NF-κB p65 protein expression. Therefore, we proposed that sodium butyrate should ameliorate STZ-induced T1D by down-regulating NF-κB mediated inflammatory signal pathway through inhibiting HMGB1.

Chronic diseases, inflammation, and spices: how are they linked?

Extensive research within the last several decades has revealed that the major risk factors for most chronic diseases are infections, obesity, alcohol, tobacco, radiation, environmental pollutants, and diet. It is now well established that these factors induce chronic diseases through induction of inflammation. However, inflammation could be either acute or chronic. Acute inflammation persists for a short duration and is the host defense against infections and allergens, whereas the chronic inflammation persists for a long time and leads to many chronic diseases including cancer, cardiovascular diseases, neurodegenerative diseases, respiratory diseases, etc. Numerous lines of evidence suggest that the aforementioned risk factors induced cancer through chronic inflammation. First, transcription factors NF-κB and STAT3 that regulate expression of inflammatory gene products, have been found to be constitutively active in most cancers; second, chronic inflammation such as pancreatitis, prostatitis, hepatitis etc. leads to cancers; third, activation of NF-κB and STAT3 leads to cancer cell proliferation, survival, invasion, angiogenesis and metastasis; fourth, activation of NF-κB and STAT3 leads to resistance to chemotherapy and radiation, and hypoxia and acidic conditions activate these transcription factors. Therefore, targeting these pathways may provide opportunities for both prevention and treatment of cancer and other chronic diseases. We will discuss in this review the potential of various dietary agents such as spices and its components in the suppression of inflammatory pathways and their roles in the prevention and therapy of cancer and other chronic diseases. In fact, epidemiological studies do indicate that cancer incidence in countries such as India where spices are consumed daily is much lower (94/100,000) than those where spices are not consumed such as United States (318/100,000), suggesting the potential role of spices in cancer prevention.

Immunomodulatory Properties and Potential Therapeutic Benefits of Muse Cells Administration in Diabetes

It is well established the link between inflammation and the development of insulin resistance and pathogenesis of type 2 diabetes. Type 1 diabetes is an autoimmune disease characterized by the destruction of insulin-producing pancreatic β cells mediated by autoreactive T lymphocytes and pro-inflammatory agents. Therefore, developing new strategies to efficiently control dysregulated inflammation could have substantial benefits in the treatment of diabetes. Recently, a novel population of non-tumorigenic pluripotent stem cells, named multilineage-differentiating stress-enduring (Muse) cells, was discovered. Muse cells secrete significant amounts of TGF-β1, a key cytokine governing down-modulation of T lymphocytes and macrophages. In this chapter, we discuss the immunomodulatory properties of Muse cells as well as the molecular mechanism of TGF-β1 as mediator of Muse cell action. We also describe the role of certain cytokines/growth factors highly expressed in Muse cells as potential mediators of their effects. Finally, we provide evidence of the beneficial effects of adipose tissue-derived Muse cells in an experimental mice model of type 1 diabetes.

Curcumin: A natural modulator of immune cells in systemic lupus erythematosus

Curcumin is a polyphenol natural product isolated from turmeric, interacting with different cellular and molecular targets and, consequently, showing a wide range of pharmacological effects. Recent preclinical and clinical trials have revealed immunomodulatory properties of curcumin that arise from its effects on immune cells and mediators involved in the immune response, such as various T-lymphocyte subsets and dendritic cells, as well as different inflammatory cytokines. Systemic lupus erythematosus (SLE) is an inflammatory, chronic autoimmune-mediated disease characterized by the presence of autoantibodies, deposition of immune complexes in various organs, recruitment of autoreactive and inflammatory T cells, and excessive levels of plasma proinflammatory cytokines. The function and numbers of dendritic cells and T cell subsets, such as T helper 1 (Th1), Th17, and regulatory T cells have been found to be significantly altered in SLE. In the present report, we reviewed the results of in vitro, experimental (pre-clinical), and clinical studies pertaining to the modulatory effects that curcumin produces on the function and numbers of dendritic cells and T cell subsets, as well as relevant cytokines that participate in SLE.

Curcumin improves diabetes mellitus‑associated cerebral infarction by increasing the expression of GLUT1 and GLUT3

Curcumin is characterized by anti‑inflammatory, anti‑oxidative, antiviral, antifibrotic, anticoagulation and glucose regulatory functions. However, whether it is protective in diabetes mellitus‑associated cerebral infarction remains to be fully elucidated. In the present study, it was demonstrated for the first time, to the best of our knowledge, that curcumin markedly improved neurological deficits, cerebral infarct volume and brain edema rate following middle cerebral artery occlusion (MCAO) surgery. It was also shown that the expression levels of glucose transporter (GLUT)1 and GLUT3 were reduced in the MCAO group. However, following curcumin treatment, the levels of GLUT1 and GLUT3 were markedly increased. In addition, curcumin markedly decreased cell apoptosis, indicating an anti‑apoptotic role of curcumin in the brain. To further evaluate whether curcumin prevented cell apoptosis by modulating the expression of GLUT1 and GLUT3, small interfering RNAs targeting GLUT1 and GLUT3 were selected. It was found that the knockdown of GLUT1 and GLUT3 inhibited the abundance of GLUT1, GLUT3 and B‑cell lymphoma 2, even following incubation with curcumin. These data showed that curcumin protected brain cells from apoptosis and cerebral infarction, predominantly by upregulating GLUT1 and GLUT3.

Nano-curcumin safely prevents streptozotocin-induced inflammation and apoptosis in pancreatic beta cells for effective management of Type 1 diabetes mellitus

BACKGROUND AND PURPOSE

Approaches to prevent selective and progressive loss of insulin-producing beta cells in Type 1 diabetes mellitus (T1DM) will help to manage this prevalent and devastating disease. Curcumin (CUR), a natural anti-inflammatory substance, suppresses diabetes-associated inflammation and cell death. However, very high doses need to be used because of poor oral bioavailability, making it difficult to translate the anti-inflammatory actions to clinical situations.

EXPERIMENTAL APPROACH

We have prepared biodegradable nanosystems encapsulating curcumin (nCUR), resulting in at least nine-fold improvement in oral bioavailability. Here, we tested the ability of nCUR to prevent streptozotocin (STZ)-induced inflammation and apoptosis in pancreatic islets and beta cells, in rats.

KEY RESULTS

Non-fasted rats pretreated with 10 or 50 mg·kg^-1 nCUR 6 h prior to STZ challenge had up to 37% reduction in the glucose levels, while plain CUR (50 mg·kg^-1 ) results in 12% reduction. This treatment with nCUR was accompanied by decreased islet or beta cell death, as shown by TUNEL assay and H&E staining. Both CUR and nCUR significantly decreased levels of inflammatory cytokines in pancreatic tissue homogenates that correlated well with minimal histiocytic infiltration. Pre-treatment with nCUR, but not CUR, decreased 8-oxo-2'-deoxyguanosine, a sensitive biomarker of ROS-induced DNA damage, in pancreas. In normal rodents, daily dosing for 28 days, with nCUR (25-100 mg·kg^-1 ) did not cause any deleterious health issues by the carrier.

CONCLUSIONS AND IMPLICATIONS

Together, these data indicate a potentially translatable dose of nCUR that is safe and efficacious in improving beta cell function, which could prevent T1DM.

Exercise Training but not Curcumin Supplementation Decreases Immune Cell Infiltration in the Pancreatic Islets of a Genetically Susceptible Model of Type 1 Diabetes

Background

The main mechanism involved in the pathogenesis of autoimmunity is an uncontrolled inflammatory response against self-antigens. Therefore, anti-inflammatory factors, such as the intake of bioactive compounds and a physically active lifestyle, may decrease or cease the development of autoimmune diseases. Type 1 diabetes (T1D) is an autoimmune disease characterized by pancreatic β cell destruction. The non-obese diabetic (NOD) mouse is a model of spontaneous T1D and is the model most similar to human disease.

Methods

To determine the effects of exercise training and curcumin supplementation on T1D progression, 48 NOD mice, 5 weeks old, were randomly divided into four groups: control, curcumin supplementation, trained, and trained plus curcumin. Every 2 weeks, blood glucose was measured using a glucometer. At the end of 20 weeks, a histopathological procedure was used to assess immune cells infiltration into pancreatic β cells (insulitis).

Results

Moderate intensity exercise training has the potential to protect pancreatic β cells against an immune response in vivo. However, curcumin supplementation failed to attenuate insulitis in NOD mice.

Conclusions

These data provide evidence that exercise training can mitigate T1D development in genetically susceptible mice.

Nutritional control of IL-23/Th17-mediated autoimmune disease through HO-1/STAT3 activation

The nutritional curcumin (CUR) is beneficial in cell-mediated autoimmune diseases. The molecular mechanisms underlying this food-mediated silencing of inflammatory immune responses are poorly understood. By investigating antigen-specific immune responses we found that dietary CUR impairs the differentiation of Th1/Th17 cells in vivo during encephalomyelitis and instead promoted Th2 cells. In contrast, feeding CUR had no inhibitory effect on ovalbumin-induced airway inflammation. Mechanistically, we found that CUR induces an anti-inflammatory phenotype in dendritic cells (DC) with enhanced STAT3 phosphorylation and suppressed expression of Il12b and Il23a. On the molecular level CUR readily induced NRF2-sensitive heme oxygenase 1 (HO-1) mRNA and protein in LPS-activated DC. HO-1 enhanced STAT3 phosphorylation, which enriched to Il12b and Il23a loci and negatively regulated their transcription. These findings demonstrate the underlying mechanism through which a nutritional can interfere with the immune response. CUR silences IL-23/Th17-mediated pathology by enhancing HO-1/STAT3 interaction in DC.

Multivariate analysis and molecular interaction of curcumin with PPARγ in high fructose diet induced insulin resistance in rats

To investigate the effect of curcumin on the multivariate and docking analysis on peroxisome proliferator activated receptor-γ, the rats were fed with high fructose diet (Group 2) to induce insulin resistance and curcumin was co-administered orally (Group 4) for a period of 8 weeks and measured the biochemical parameters in blood, kidney and liver tissues. The results showed a significant (p ≤ 0.05) increase in the level of creatinine, glucose, insulin, low density lipoprotein, total cholesterol, triglyceride, urea, uric acid, very low density lipoprotein and decreased albumin, high density lipoprotein and total protein level in the blood of Group 2 when compared with Group 1 control rats. Further, analysis on liver and kidney tissues showed a significant decrease in antioxidants, hexokinase and increased glucose 6-phosphatase and fructose 1,6-bisphosphatase, hydroperoxides and TBARS in Group 2 rats. Furthermore, the multivariate and loading coefficient analysis showed that albumin, HDL, catalase, glutathione reductase, hexokinase and vitamin E are the most contributing factors in blood, liver and kidney. Subsequently, molecular docking was carried out to determine the binding efficiency of curcumin as agonist of PPARγ showed high affinity compared to pioglitazone. The histology of liver and kidney were also studied and the administration of curcumin along with fructose protects the organs from the abnormal changes and also prevents the fat accumulation. Overall, these results demonstrate the preventive role of curcumin on diet induced insulin resistant in rats by ameliorating the altered levels of metabolic changes and potential binding of curcumin with PPARγ as agonist in the treatment of insulin resistance.

Effects of curcumin in experimental diabetic nephropathy

Diabetic nephropathy (DN) is currently well established as the most common cause of end-stage renal disease in most parts of the world. Notwithstanding the expanding basic and clinical research in this field, the pathogenesis remains far from clear and hence the treatment of DN remains suboptimal. There is a critical need for the development of newer therapeutic strategies including alternative and complementary therapies. One of the natural products that was extensively studied in cancer and other chronic disease states such as diabetes is curcumin, an active ingredient in turmeric, a spice extensively used in India. In this manuscript, we present a critical review of the experimental and clinical evidence that supports the use of curcumin and its analogs in DN as well as the various proposed mechanisms for its biological actions in health and disease states.

Pluripotent Nontumorigenic Adipose Tissue-Derived Muse Cells have Immunomodulatory Capacity Mediated by Transforming Growth Factor-β1

Adult mesenchymal stromal cell‐based interventions have shown promising results in a broad range of diseases. However, their use has faced limited effectiveness owing to the low survival rates and susceptibility to environmental stress on transplantation. We describe the cellular and molecular characteristics of multilineage‐differentiating stress‐enduring (Muse) cells derived from adipose tissue (AT), a subpopulation of pluripotent stem cells isolated from human lipoaspirates. Muse‐AT cells were efficiently obtained using a simple, fast, and affordable procedure, avoiding cell sorting and genetic manipulation methods. Muse‐AT cells isolated under severe cellular stress, expressed pluripotency stem cell markers and spontaneously differentiated into the three germ lineages. Muse‐AT cells grown as spheroids have a limited proliferation rate, a diameter of ∼15 µm, and ultrastructural organization similar to that of embryonic stem cells. Muse‐AT cells evidenced high stage‐specific embryonic antigen‐3 (SSEA‐3) expression (∼60% of cells) after 7–10 days growing in suspension and did not form teratomas when injected into immunodeficient mice. SSEA‐3⁺‐Muse‐AT cells expressed CD105, CD29, CD73, human leukocyte antigen (HLA) class I, CD44, and CD90 and low levels of HLA class II, CD45, and CD34. Using lipopolysaccharide‐stimulated macrophages and antigen‐challenged T‐cell assays, we have shown that Muse‐AT cells have anti‐inflammatory activities downregulating the secretion of proinflammatory cytokines, such as interferon‐γ and tumor necrosis factor‐α. Muse‐AT cells spontaneously gained transforming growth factor‐β1 expression that, in a phosphorylated SMAD2‐dependent manner, might prove pivotal in their observed immunoregulatory activity through decreased expression of T‐box transcription factor in T cells. Collectively, the present study has demonstrated the feasibility and efficiency of obtaining Muse‐AT cells that can potentially be harnessed as immunoregulators to treat immune‐related disorders. Stem Cells Translational Medicine2017;6:161–173

Piperine from black pepper inhibits activation-induced proliferation and effector function of T lymphocytes

Piperine is a major alkaloid component of black pepper (Piper nigrum Linn), which is a widely consumed spice. Here, we investigated the effect of piperine on mouse T lymphocyte activation. Piperine inhibited polyclonal and antigen-specific T lymphocyte proliferation without affecting cell viability. Piperine also suppressed T lymphocyte entry into the S and G2 /M phases of the cell cycle, and decreased expression of G1 -associated cyclin D3, CDK4, and CDK6. In addition, piperine inhibited CD25 expression, synthesis of interferon-γ, interleukin (IL)-2, IL-4, and IL-17A, and the generation of cytotoxic effector cells. The inhibitory effect of piperine on T lymphocytes was associated with hypophosphorylation of Akt, extracellular signal-regulated kinase, and inhibitor of κBα, but not ZAP-70. The ability of piperine to inhibit several key signaling pathways involved in T lymphocyte activation and the acquisition of effector function suggests that piperine might be useful in the management of T lymphocyte-mediated autoimmune and chronic inflammatory disorders.