Curcumin and Its Role in Chronic Diseases

Comparative effects of curcumin versus nano-curcumin on histological, immunohistochemical expression, histomorphometric, and biochemical changes to pancreatic beta cells and lipid profile of streptozocin induced diabetes in male Sprague-Dawley rats

Diabetes mellitus is a worldwide problem characterized by hyperglycemia as well as the damage of the microscopic structure of the beta cells of Langerhans pancreatic islets. In the present study, the histological, immunohistochemical, morphometric, and biochemical alterations to pancreatic beta cells in streptozocin (STZ)-induced diabetes were assessed in rats treated with curcumin (CU) (100 mg/kg/day) or nano-curcumin (nCU) (100 mg/kg/day) for 1 month. Twenty-four adult male Wistar albino rats were distributed into four groups: the nondiabetic control group, the diabetic untreated group, and two diabetic groups treated with CU or nCUR, respectively. Blood glucose, serum insulin levels, and lipid profile were measured. The pancreatic tissues were collected and processed into paraffin sections for histological and immunohistochemical examination, oxidative stress markers, and real-time PCR expression for pancreatic and duodenal homeobox 1 (PDX1). The insulin expression in beta cells was assessed using immunohistochemistry. Morphometrically, the percentage area of anti-insulin antibody reaction and the percentage area of islet cells were determined. STZ-induced deteriorating alteration in beta cells led to declines in the number of functioning beta cells and insulin immunoreactivity. In STZ-treated rats, CU and nCUR significantly reduced blood glucose concentration while increasing blood insulin level. It also caused a significant increase in the number of immunoreactive beta cells to the insulin expression and significant reduction of the immunoreactive beta cells to the caspase-3 expression. In conclusion, CU and nCUR could have a therapeutic role in the biochemical and microscopic changes in pancreatic beta cells in diabetes-induced rats through STZ administration with more bio-efficacy of nCUR.

Curcumin-Loaded Mesenchymal Stem Cell-Derived Exosomes Efficiently Attenuate Proliferation and Inflammatory Response in Rheumatoid Arthritis Fibroblast-Like Synoviocytes

This study aimed to evaluate the potential of mesenchymal stem cell-derived exosomes loaded with curcumin (Curc-Exos) as an effective therapeutic strategy for rheumatoid arthritis through modulation of proliferation and inflammatory response in HIG-82 synovial cells. For this purpose, Exos were isolated and characterized with BCA protein assay, DLS, FE-SEM, and TEM. The Curc was embedded by mixing it with Exos in a 1:4 ratio. It was found that the Curc stability has improved after loading on Exos compared to the free Curc. Besides, the in vitro studies using LPS-stimulated HIG-82 synovial cells indicated the efficiency of Curc-Exos in enhancing cytotoxicity and apoptosis compared to the free Curc treatment. It was also revealed that Curc-Exos significantly could reduce the expression levels of anti-apoptotic proteins IAP1 and IAP2 and inflammatory mediators including IL-6, TNF-α, MMP1, and PGE2. This preliminary study confirmed the suitability of Curc-Exos in counteracting the proliferation and inflammatory response of rheumatoid arthritis synovial fibroblasts in vitro.

Curcumin Alleviates DSS-Induced Anxiety-Like Behaviors via the Microbial-Brain-Gut Axis

The anxiety and depression caused by inflammatory bowel diseases (IBD) are known to greatly affect the mental health of patients. The mechanism of psychiatric disorders caused by IBD is not fully understood. Previous research has suggested that the gut microbiome plays a key role in IBD. Curcumin is a yellow polyphenol extracted from the rhizome of the ginger plant, which has been shown to have effects against both depression and anxiety. Research has indicated that curcumin affects the gut microbiome and exerts antianxiety and neuroprotective effects through the microbiota-gut-brain axis (MGB). However, whether curcumin can alleviate the psychiatric disorders caused by IBD and how curcumin affects the MGB axis through the gut microbiota have not been fully understood. Therefore, this study was aimed at determining the metabolic parameters and microbiological environment in the peripheral and central nervous system to determine the effects of curcumin against anxiety induced by dextran sulfate sodium salt (DSS) in mice. To elaborate on the link between the gut microbiota and how curcumin alleviates anxiety-like behaviors, we performed a fecal microbiota transplantation (FMT) experiment. The results suggested that curcumin can effectively relieve anxiety-like behaviors caused by DSS in mice. Further, curcumin treatment can alleviate disturbances in the gut microbiota and systemic disorders of lipid metabolism caused by DSS. Finally, through FMT, we verified that curcumin increased phosphatidylcholine in the prefrontal cortex of the mice and alleviated DSS-induced anxiety-like behaviors by modulating specific gut microbiota. We also revealed that Muribaculaceae may be a key part of the gut microbiota for curcumin to alleviate DSS-induced anxiety-like behaviors through the MGB axis.

An overview on therapeutic role of Diferuloylmethane (Curcumin) in Azheimer’s disease and sleep disorders

Curcumin is widely used in spices in Asia. It has been widely explored for various diseases as therapeutic agent. Alzheimer’s disease (AD) is a neurodegenerative disease associated with dementia and cognitive disabilities. With the progression of disease, various changes appear in the brain cells that greatly affect the daily routine of the patient including sleep-wake disturbances. In the last few decades, extensive research has been carried out on this disease suggesting the development of non-steroidal anti-inflammatory drugs for its treatment. Since long, turmeric has been used in Asian countries as a home remedy for treating various ailments. Curcumin is an active ingredient isolated from the turmeric plant and is composed of curcuminoids. Because of its anti-inflammatory, antioxidant, anti-apoptotic and neuroprotective properties, curcumin can be safely administered to stop the progression of dementia and can be used for the development of such drugs that can reverse the neurotic damage caused by AD. This review article provides a comprehensive overview on the research carried out for AD using curcumin as active model drug.

Targeted Delivery of Curcumin to Polyethylene-Induced Osteolysis by Magnetically Guided Zoledronate-Anchored Poly Lactic-Co-Glycolic Acid Nanoparticles via Repressing NF-κB Signaling

Aseptic loosening induced by periprosthetic osteolysis (PPO) is the leading complication of total joint arthroplasty (TJA) and results in patients having to receive revision surgery. However, there is still no efficient drug to prevent or even slow the pathological process. Herein, we report novel dual-targeted, curcumin-loaded Poly lactic-co-glycolic acid nanoparticles (ZSCNPs) to inhibit polyethylene-induced osteolysis. These ZSCNPs have good biocompatibility and excellent bone binding affinity. Under external magnetic field guidance, the ZSCNPs can specifically target osteolytic sites with sustained curcumin release, efficiently suppress the effect of IκB kinase, subsequently inhibit activation of the nuclear factor-kappa B (NF-κB) signaling pathway, and ultimately prevent osteoclast formation and particle-induced osteolysis. Therefore, these novel dual-targeted, drug-loaded nanoparticles could be applied as a useful strategy for targeted treatment of PPO after TJA.

Dietary Supplementation with Palmitoyl-Glucosamine Co-Micronized with Curcumin Relieves Osteoarthritis Pain and Benefits Joint Mobility

Simple Summary

Canine osteoarthritis is a chronic degenerative joint disease and a major cause of elective euthanasia. The disorder increasingly limits joint motion, might cause lameness as well as pain, and impacts quality of life. An unmet need remains for safe and effective therapies for osteoarthritis. Palmitoyl-glucosamine and curcumin are used in animal nutrition. A co-micronized formulation, with the two substances being jointly processed to reduce their particle size and increase the extent to which they can be absorbed, is currently available on the European market. The present study investigated if this formulation could relieve joint pain and benefit mobility. Two well-established rat models of inflammation and osteoarthritis pain were used. Results from the first set of experiments showed that the dietary supplement relieved experimentally induced paw edema, infiltration of inflammatory cells, and decreased sensitivity to painful stimuli (thermal hyperalgesia). In the osteoarthritis model, the supplement proved to protect joint cartilage against degradation and successfully address neuropathic pain (i.e., pain from normally non-painful stimuli). Locomotor function recovered by 45% under supplement administration. The present findings suggest that the dietary supplement with palmitoyl-glucosamine co-micronized with curcumin might help manage osteoarthritis.

Abstract

Chronic mixed pain and orthopedic dysfunction are the most frequently associated consequences of canine osteoarthritis (OA). An unmet need remains for safe and effective therapies for OA. Palmitoyl-glucosamine (PGA) and curcumin are safe and naturally occurring compounds whose use is limited by poor bioavailability. Micronization is an established technique to increase bioavailability. The aim of this study was to investigate if the dietary supplementation with PGA co-micronized with curcumin (PGA-Cur, 2:1 ratio by mass) could limit pathologic process in two well-established rat models of inflammation and OA pain, i.e., subplantar carrageenan (CAR) and knee injection of sodium monoiodoacetate (MIA), respectively. In CAR-injected animals, a single dose of PGA-cur significantly reduced paw edema and hyperalgesia, as well as tissue damage and neutrophil infiltration. The repeated administration of PGA-Cur three times per week for 21 days, starting the third day after MIA injection resulted in a significant anti-allodynic effect. Protection against cartilage damage and recovery of locomotor function by 45% were also recorded. Finally, PGA-cur significantly counteracted MIA-induced increase in serum levels of TNF-α, IL-1β, NGF, as well as metalloproteases 1, 3, and 9. All the effects of PGA-Cur were superior compared to the compounds used singly. PGA-Cur emerged as a useful dietary intervention for OA.

Interaction between Gut Microbiota and Curcumin: A New Key of Understanding for the Health Effects of Curcumin

Curcumin, a lipophilic polyphenol contained in the rhizome of Curcuma longa (turmeric), has been used for centuries in traditional Asian medicine, and nowadays it is widely used in food as dietary spice worldwide. It has received considerable attention for its pharmacological activities, which appear to act primarily through anti-inflammatory and antioxidant mechanisms. For this reason, it has been proposed as a tool for the management of many diseases, among which are gastrointestinal and neurological diseases, diabetes, and several types of cancer. However, the pharmacology of curcumin remains to be elucidated; indeed, a discrepancy exists between the well-documented in vitro and in vivo activities of curcumin and its poor bioavailability and chemical instability that should limit any therapeutic effect. Recently, it has been hypothesized that curcumin could exert direct regulative effects primarily in the gastrointestinal tract, where high concentrations of this polyphenol have been detected after oral administration. Consequently, it might be hypothesized that curcumin directly exerts its regulatory effects on the gut microbiota, thus explaining the paradox between its low systemic bioavailability and its wide pharmacological activities. It is well known that the microbiota has several important roles in human physiology, and its composition can be influenced by a multitude of environmental and lifestyle factors. Accordingly, any perturbations in gut microbiome profile or dysbiosis can have a key role in human disease progression. Interestingly, curcumin and its metabolites have been shown to influence the microbiota. It is worth noting that from the interaction between curcumin and microbiota two different phenomena arise: the regulation of intestinal microflora by curcumin and the biotransformation of curcumin by gut microbiota, both of them potentially crucial for curcumin activity. This review summarizes the most recent studies on this topic, highlighting the strong connection between curcumin and gut microbiota, with the final aim of adding new insight into the potential mechanisms by which curcumin exerts its effects.

Effects of curcumin supplementation on sport and physical exercise: a systematic review

Curcumin is the main phenolic compound in turmeric. It has been investigated recently due to its numerous medicinal properties and health benefits. However, few studies assessed the effects of curcumin supplementation on physical activity practice. Therefore, the purpose of this review is to assess the available evidences with human beings about the potential effects of curcumin supplementation on sport and physical exercise. This systematic review was conducted within the period from January to February, 2019, following the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) guidelines. The LILACS, Medline, SciELO and PubMed databases were used for the search, with no publication date limit. The following terms, with the respective Boolean operators, were searched: "curcumin" AND sports; "curcumin" AND exercise; curcumin AND "aerobic exercise"; "curcumin" AND "resistance exercise"; "curcumin" AND "endurance exercise"; "curcumin" AND "strength exercise". Eleven papers were selected for this review. Most of the studies displayed positive effects of the curcumin supplementation for athletes and physical exercise practitioners, and no side effects were reported. Participants supplemented with curcumin displayed reduced inflammation and oxidative stress, decreased pain and muscle damage, superior recovery and muscle performance, better psychological and physiological responses (thermal and cardiovascular) during training and improved gastrointestinal function. Curcumin supplementation appears to be safe and beneficial for sport and physical exercise in human beings. PROSPERO (CRD42019126763).

Impact of curcumin delivery system format on bioaccessibility: nanocrystals, nanoemulsion droplets, and natural oil bodies

Curcumin, a hydrophobic yellow-orange crystalline substance derived from plants, is claimed to exhibit a broad range of biological activities. Its application in functional foods and beverages is often limited by its low solubility in aqueous media, chemical instability, and low bioavailability. Previously, we have shown that curcumin can be successfully loaded into emulsions using the pH-shift method. In this study, we compared the efficacy of curcumin crystals dispersed in water (control) with three delivery systems produced using the pH-shift method: curcumin nanocrystals; curcumin-loaded nanoemulsions; and curcumin-loaded soy oil bodies. The nanoemulsions and oil bodies formed creamy yellow dispersions that were stable to creaming, whereas the nanocrystals formed a cloudy yellow-orange suspension that was prone to sedimentation. The gastrointestinal fate of the delivery systems was assessed using a static in vitro digestion model consisting of mouth, stomach, and small intestine phases. The nanoemulsions and oil bodies were rapidly and fully digested, while the nanocrystals were not. All three systems were relatively stable to chemical transformation in the in vitro digestion model. The nanocrystals gave a low bioaccessibility but the other two systems gave a high bioaccessibility, which was attributed to their ability to form mixed micelles to solubilize the curcumin. These results have important implications for the creation of more effective delivery systems for curcumin.

CD44 targeting biocompatible and biodegradable hyaluronic acid cross-linked zein nanogels for curcumin delivery to cancer cells: In vitro and in vivo evaluation

In this study, we developed novel hyaluronic acid cross-linked zein nanogels (HA-Zein NGs) to deliver the potential anticancer agent curcumin (CRC), a naturally occurring phytochemical drug in cancer cells. In vitro studies showed that they are highly compatible with the tested cell lines. They showed CD44 specific uptake in CT26 cell line more than by the CD44 receptor pre-inhibited CT26 cells. The CRC encapsulated HA-Zein NGs (HA-Zein-CRC NGs) found to exert a specific toxicity against CT26 sparing healthy normal fibroblast cells in vitro. The apoptotic effects were further confirmed with flow cytometry showing that the HA-Zein-CRC NGs exhibited high anticancer activity against the CT26 cells. The in vivo bio-distribution with a CT26 tumor model showed their high tumor accumulation thereby improved antitumor efficacy with a low dosage of CRC, compared to the previous reports. Thus, the preclinical studies clearly showed that these novel HA-Zein NGs would be highly beneficial in encapsulating hydrophobic drugs with improved pharmacokinetics thereby enhancing the therapeutic outcomes.

The Problem of Curcumin and Its Bioavailability: Could Its Gastrointestinal Influence Contribute to Its Overall Health-Enhancing Effects?

Curcumin, from the spice turmeric, exhibits anti-inflammatory, antioxidant, anticancer, antiviral, and neurotrophic activity and therefore holds promise as a therapeutic agent to prevent and treat several disorders. However, a major barrier to curcumin's clinical efficacy is its poor bioavailability. Efforts have therefore been dedicated to developing curcumin formulations with greater bioavailability and systemic tissue distribution. However, it is proposed in this review that curcumin's potential as a therapeutic agent may not solely rely on its bioavailability, but rather its medicinal benefits may also arise from its positive influence on gastrointestinal health and function. In this review, in vitro, animal, and human studies investigating the effects of curcumin on intestinal microbiota, intestinal permeability, gut inflammation and oxidative stress, anaphylactic response, and bacterial, parasitic, and fungal infections are summarized. It is argued that positive changes in these areas can have wide-ranging influences on both intestinal and extraintestinal diseases, and therefore presents as a possible mechanism behind curcumin's therapeutic efficacy.