Browning white adipose tissue using adipose stromal cell-targeted resveratrol-loaded nanoparticles for combating obesity

Cellular and Molecular Mechanisms of Phytochemicals Against Inflammation-Associated Diseases and Viral Infection

Inflammation-associated diseases have become widespread and pose a significant threat to human health, and the therapeutic methods for diverse diseases are inadequate due to the undesirable effects of synthetic ingredients. Recently, more and more evidence indicated that phytochemicals, plant secondary metabolites, have numerous therapeutic functions against human diseases via affecting a variety of mechanisms with their distinct advantages of high efficiency and low toxicity. Here, we highlight the mechanisms of phytochemicals to hinder inflammation-associated diseases (including Inflammatory diseases, cardiovascular diseases, metabolic syndrome, neurological disorders, skin diseases, respiratory diseases, kidney diseases, gastrointestinal diseases, retinal diseases, viral infections) by regulating the crosstalk among various signal cascades (including MicroRNAs, SIRT1, DNMTs, NF-κB, NLRP3, TGF-β, the Gasdermin-mediated pyroptosis pathway), which can be considered as a novel and potential therapeutic strategy. Furthermore, phytochemicals could prevent virus infection by disturbing different targets in the virus replication cycle. However, natural plants have shown limited bioavailability due to their low water solubility, the use of adjuvants such as liposomal phytochemicals, phytochemical nanoparticles and phytochemicals-phospholipid complex promote their bioavailability to exhibit beneficial effects against various diseases. The purpose of this review is to explore the molecular mechanisms and promising applications of phytochemicals in the fields of inflammation-associated diseases and virus infection to provide some direction.

Hyaluronic acid-based hesperidin nanostructured lipid carriers loaded dissolving microneedles: A localized delivery approach loaded for the management of obesity

Obesity, a persistent imbalance of calories, has become one of the major clinical factors that result in many metabolic disorders. Despite excellent anti-obesity properties, the poor aqueous solubility of hesperidin (HES), a flavonoid, hampers its applicability. To resolve this issue and conquer oral administration's drawbacks, our study has concentrated on encapsulating HES in nanostructured lipid carriers (NLCs) and incorporating the NLCs into microneedles (MNs). By developing HES-loaded NLCs (HES-NLCs) with hyaluronic acid (HA) as a base design to form a microneedle patch (HES-NLCMNP), the study aimed to increase the stability and bioavailability of HES and provide an innovative way for the management of obesity. HES-NLCs were loaded to the microneedle, to promote anti-obesity activity. The microneedle tip, which has been composed of HA, will act as a biodegradable polymer that could effectively deliver the activity of HES-NLC to the blood stream. Furthermore, the base of the microneedle patch composed of polyvinyl alcohol (PVA) offered excellent flexibility, releasing HES and providing resistance to any adverse effects. Analysis revealed that the prepared HES-NLCs have desirable physical characteristics with an extended-release profile. The optimised NLC formulation (F3F) was later incorporated into HA-base-designed MNs that demonstrated mechanical solid integrity and effective skin penetration. In vivo pharmacokinetics significantly improved all parameters with a reduced elimination rate. Physiological, haematological, and antioxidant markers improved in treated rats, with histopathological analysis showing significant tissue alterations. The results suggest that HES-NLCMNP is a promising platform to improve drug effectiveness, patient compliance, and treatment outcomes for obesity.

Adipose tissue-targeting nanomedicines for obesity pharmacotherapy

The increasing global prevalence of obesity presents a substantial challenge to public health. Current nutrient-stimulated hormone (NuSH)-based therapeutics are hindered by receptor desensitization, muscle loss, and weight regain. The adipose tissue, the primary organ responsible for energy storage and metabolic management, is a promising target for obesity treatment. Nanomedicine holds promise to precisely deliver medication to the adipose tissue to maximize therapeutic efficacy and minimize off-target effects; indeed, various adipose tissue-targeting nanomedicines have shown impressive anti-obesity effects by optimizing drug pharmacokinetic profiles and reducing nonspecific distribution in preclinical studies. Here we examine the current state of the art of adipose tissue-targeting nanomedicines, offering insights into recent advances, future possibilities, and the remaining challenges associated with their application in obesity treatment.

Recent Advances in the Anti-Obesity Benefits of Phytoconstituents: From Phytochemistry to Targeting Novel-Systems

Obesity is a metabolic disorder that has become a global health concern. The existing pharmaceutical drugs for treating obesity have some side effects. Compounds from natural sources are prospective substitutes for treating chronic diseases such as obesity, with the added advantages of being safe and cost-effective. However, due to factors such as poor solubility, low bioavailability, and instability in the physiological environment, the therapeutic efficacy of phytoconstituents is limited. Nowadays, developing nanoscaled systems has emerged as a vital strategy for enhancing the delivery and therapeutic effect of phytoconstituents. The present study discusses and categorizes phytoconstituents with anti-obesity effects and concludes the main mechanisms underlying their effects. Importantly, strategies used to develop phytoconstituent-based nano-drug delivery systems (NDDS) for obesity treatment that show improved efficacy relative to traditional administration routes are reviewed. Finally, the progress of research on phytoconstituent-based NDDS for obesity treatment is summarized to provide a reference for the development of safe and effective treatment strategies for obesity.

Resveratrol: A Narrative Review Regarding Its Mechanisms in Mitigating Obesity-Associated Metabolic Disorders

Resveratrol (RSV) is a naturally occurring astragalus-like polyphenolic compound with remarkable weight loss properties. However, the mechanism of RSV in treating obesity is unclear. In this narrative review, we explored electronic databases (PubMed) for research articles from 2021 to the present using the keywords "resveratrol" and "obesity". This article explores the mechanisms involved in the alleviation of obesity-related metabolic disorders by RSV. RSV affects obesity by modulating mitochondrial function, insulin signaling, and gut microbiota, regulating lipid metabolism, inhibiting oxidative stress, and regulating epigenetic regulation. Administering RSV to pregnant animals exhibits maternal and first-generation offspring benefits, and RSV administration to lactating animals has long-term benefits, which involve the epigenetic modulations by RSV. A comprehensive understanding of the epigenetic mechanisms of RSV regulation could help in developing drugs suitable for pregnancy preparation groups, pregnant women, and nursing infants.

Dermal drug delivery via bilosomes: a synergistic integration for better therapeutic outcomes

The dermal route is commonly used to deliver the drugs at the targeted site and achieve maximum therapeutic efficacy. The stratum corneum, the uppermost layer of the skin, presents a significant diffusional barrier for most drugs. Various nanoformulations face challenges such as limited drug absorption and inadequate retention at the targeted site, frequently hindering therapeutic efficacy. Researchers are increasingly exploring innovative strategies that leverage nanotechnology and specialized carriers to address these challenges and enhance the outcomes of dermal medications. A novel drug delivery system, bilosomes, has been designed as a potential vesicular carrier system for the dermal route. Bilosomes are colloidal, lipid-based vesicles stabilized with bile salts, offering greater stability during storage and transportation. The lipid bilayer of bilosomes imparts ultra-flexibility, facilitating penetration through the stratum corneum. This review explores the use of bilosomes in dermal formulations for treating diverse diseases, their developmental techniques, and characterization, and it sheds light on their advantages over traditional lipid nanocarriers.

Effects of Resveratrol on Adipocytes: Evidence from In Vitro and In Vivo Studies

Obesity, a prevalent global health issue, arises from an imbalance between caloric intake and energy expenditure, leading to the expansion of adipose tissue and metabolic dysfunction. White adipose tissue (WAT) stores energy as lipids, while brown adipose tissue (BAT) plays a pivotal role in energy dissipation through adaptive thermogenesis. Recent research initiatives have focused on finding strategies to decrease adipogenesis and fat mass accumulation and increase thermogenesis. Finding chemicals with anti-obesity properties would be beneficial. Resveratrol, a polyphenolic compound abundantly found in the skin of grapes and red wine, possesses anti-oxidant, anti-inflammatory, anti-cancer, and anti-obesity properties. This literature review examines the effects of resveratrol on adipocytes in culture and adipose tissue in animal models of obesity. The existing evidence indicates that resveratrol may exert its anti-obesity effects by inhibiting adipogenesis, promoting the apoptosis of mature adipocytes, reducing lipid accumulation, and increasing thermogenesis. Further research utilizing animal and clinical studies is required to understand in detail the anti-obesity potential of resveratrol.

Development and Evaluation of Reconstructed Nanovesicles from Turmeric for Multifaceted Obesity Intervention

The escalating prevalence of obesity poses significant health challenges due to its direct association with various diseases. Most existing medications, such as appetite suppressants and fat absorption inhibitors, suffer from limited effectiveness and undesirable side effects. Here, inspired by the versatile metabolic effects of turmeric, we developed a naturally derived nanoformulation of "Reconstructed Turmeric-derived Nanovesicles (Rec-tNVs)" for obesity treatment. Employing quantitative nanoflow cytometry, a four-orders-of-magnitude increase in curcumin content (∼108 molecules per particle) was identified in individual Rec-tNVs compared to their ultracentrifugation-isolated counterparts. Rec-tNVs, featuring highly aggregated curcumin arrangements and other coencapsulated bioactive compounds, demonstrated a dose-dependent lipid-lowering effect in mature 3T3-L1 cells by promoting lipolysis, suppressing lipogenesis, inducing adipocyte browning, and triggering apoptosis after internalization via multiple pathways. In vivo experiments revealed that Rec-tNVs alleviated obesity more effectively than free curcumin and achieved weight reductions of 18.68 and 14.56% through intragastric and subcutaneous delivery, respectively, in high-fat-diet mouse models over a four-week treatment period. These effects were attributed to targeted actions on adipose tissues and systemic impacts on metabolism and gut microbiota composition. Overall, this study underscores the multifaceted antiobesity efficacy of Rec-tNVs, and offers a promising paradigm for developing plant-derived nanovesicle-based therapeutics.

Transdermal microneedle patches as a promising drug delivery system for anti-obesogenic molecules

Obesity, characterized by excessive storage of lipids, has become a global pandemic with high incidence levels, and its forecast is not encouraging. Currently, there are different strategies to treat obesity; however, these conventional methods have various limitations. Lifestyle changes may result in poor outcomes due to the complexity of obesity causes, pharmaceutic treatments produce severe side effects, and bariatric surgery is highly invasive. In the search for alternative treatments to fight obesity, transdermal drug delivery systems of anti-obesogenic molecules have gained particular attention. However, the diffusion of molecules through the skin is the main drawback due to the characteristics of different layers of the skin, principally the stratum corneum and its barrier-like behavior. In this sense, microneedles patches (MP) have emerged to overcome this limitation by piercing the skin and allowing drug delivery inside the body. Although MP have been studied for some years, it was not until about 2017 that their potential as anti-obesogenic treatment was reported. This article aims to summarize and analyze the strategies employed to produce MP and to embed the active molecules against obesity. Special attention is focused on the microneedle's material, geometry, array, and additional delivery strategies, like nanoencapsulation. MP are a promising tool to develop an easy-access treatment, avoiding the digestive tract and with the capacity to enhance the anti-obesogenic activity by delivering one or more active molecules.

Insights into formation and stability mechanism of V7-type short amylose-resveratrol complex using molecular dynamics simulation and molecular docking

Pre-formed V-type amylose as a kind of wall material has been reported to carry polyphenols, while the interaction mechanism between V-type amylose and polyphenol is still elusive. In this work, the formation and stability mechanism of a V7-type short amylose-resveratrol complex was investigated via isothermal titration calorimetry, molecular dynamics, and molecular docking. The results presented that two stoichiometric ratios of resveratrol to short amylose were calculated to 0.120 and 0.800, and the corresponding main driving force was hydrogen bonding and hydrophobic interaction, respectively. The folding and unfolding conformation of V7-type short amylose chains appeared alternately during the simulation. Resveratrol tended to be bound in the short amylose helix between 40 ns and 80 ns to form a more stable complex. Hydrogen bonds between resveratrol molecule and O6 at the 22nd glucose molecule/O2 at the 24th glucose molecules and hydrophobic interaction between resveratrol molecule and glucose molecules (19th, 20th, 21st and 23rd) could be found.

Localized trans-browning and pro-angiogenesis inductive self-assembled collagen resveratrol bio-matrix for tissue repair and regeneration in obese conditions

The present study probes into the complexities of wound management in obesity by proposing a novel biomaterial designed to reprogram the altered skin physiology prevalent in obese conditions. The strategy involves the development of a multifunctional biomaterial addressing issues such as excessive exudate, pressure ulcers, and reduced vascularity. The bio-matrix demonstrates the localized transformation of white adipocytes through trans-browning, coupled with the simultaneous induction of angiogenesis at obese wound sites, resulting in expedited wound closure. The collagen bio-matrices, stabilized with Resveratrol (Rsv), exhibit remarkable thermal, mechanical, and biological stability. The porous 3D microstructure of the Rsv-stabilized collagen bio-matrix closely resembled the natural extracellular matrix, facilitating effective cell adhesion. The bio-matrix exhibited the unique capability to induce localized thermogenesis in the subcutaneous fat layer while concurrently activating angiogenesis. In vivo wound healing studies conducted on DIO-C57BL6 mice demonstrated complete healing within 10 days, showcasing accelerated tissue regeneration, blood vessel formation, robust collagen deposition, and significant activation of browning in the subcutaneous adipose layer. This study introduces the concept of tailored regenerative biomaterials with the ability to reprogram the challenging wound environment associated with obesity. This innovative approach opens up new avenues for enhanced wound care strategies, particularly for bariatric patients.

An update on the secretory functions of brown, white, and beige adipose tissue: Towards therapeutic applications

Adipose tissue, including white adipose tissue (WAT), brown adipose tissue (BAT), and beige adipose tissue, is vital in modulating whole-body energy metabolism. While WAT primarily stores energy, BAT dissipates energy as heat for thermoregulation. Beige adipose tissue is a hybrid form of adipose tissue that shares characteristics with WAT and BAT. Dysregulation of adipose tissue metabolism is linked to various disorders, including obesity, type 2 diabetes, cardiovascular diseases, cancer, and infertility. Both brown and beige adipocytes secrete multiple molecules, such as batokines, packaged in extracellular vesicles or as soluble signaling molecules that play autocrine, paracrine, and endocrine roles. A greater understanding of the adipocyte secretome is essential for identifying novel molecular targets in treating metabolic disorders. Additionally, microRNAs show crucial roles in regulating adipose tissue differentiation and function, highlighting their potential as biomarkers for metabolic disorders. The browning of WAT has emerged as a promising therapeutic approach in treating obesity and associated metabolic disorders. Many browning agents have been identified, and nanotechnology-based drug delivery systems have been developed to enhance their efficacy. This review scrutinizes the characteristics of and differences between white, brown, and beige adipose tissues, the molecular mechanisms involved in the development of the adipocytes, the significant roles of batokines, and regulatory microRNAs active in different adipose tissues. Finally, the potential of WAT browning in treating obesity and atherosclerosis, the relationship of BAT with cancer and fertility disorders, and the crosstalk between adipose tissue with circadian system and circadian disorders are also investigated.

Modulation of angiogenic switch in reprogramming browning and lipid metabolism in white adipocytes

Thermogenic activation via trans-and de novo browning of white adipocytes is a promising strategy to accelerate lipid metabolism for regulating obesity-related disorders. In this study, we investigated the intricate interplay between angiogenic regulation and browning in white adipocytes using the bioactive compound, resveratrol (Rsv). Rsv has previously been documented for its regulatory influence on the trans and de novo browning of white adipocytes. Our findings revealed that concurrent activation of angiogenesis is prerequisite for inducing browning within the microenvironment of white adipocytes when exposed to browning activators. Additionally, we observed a significant browning effect on white adipocytes when the local adipose tissue environment was prompted to undergo angiogenesis, notably facilitated by a proangiogenic molecule known as Vascular endothelial growth factor (VEGF). Intriguingly, this effect was reversed when angiogenesis was inhibited by treatment with the antiangiogenic agent thalidomide. Furthermore, the study revealed the role of VEGF in paracrine activation of white adipocytes resulting in the induction of browning in both 3T3-L1 cell lines and primary mouse white adipocytes. The cross-talk between angiogenesis and browning was found to be initiated via the transcriptional activation of Estrogen receptor α (ERα) triggering the VEGF/VEGFR2 signaling pathway leading to browning and a reconfiguration of lipid metabolism within adipocytes. In conclusion, this study sheds light on the intricate cross-talk between angiogenesis and browning of white adipocytes. Notably, the findings underscore the reciprocal relationship between these processes, wherein inhibition of one process exerts discernible effects on the other.

Targeted Nano-Based Systems for the Anti-Obesity Agent's Delivery

Obesity is a global health concern and a chronic disease that is accompanied by excessive fat storage in adipose and nonadipose tissues. An increase in the body-mass index (BMI) is directly proportional to the 2- to 3.9-fold increase in all-cause mortality in obesity. If left untreated for a longer period, obesity-related metabolic, cardiovascular, inflammatory, and malignant diseases reduce life expectancy. Currently, most of the anti-obesity drugs have failed and fallen into disrepute, either due to their ineffectiveness or adverse effects. In this review, depending on their enhanced pharmacokinetic and biodistribution profiles, whether nanocarriers alter the basic properties and bioactivity of anti-obesity drugs used in clinical practice are debated. First, nanocarriers can improve the safety of still-used anti-obesity drugs by lowering their systemic toxicity through increasing targeting efficacy and preventing drug carrier toxicity. Second, when the micro-ribonucleic acids (miRNAs), which are aberrantly expressed in obesity and obesity-related diseases, are encapsulated into nanoparticles, they are effective in multiple obesity-related metabolic pathways and gene networks. Finally, a synergistic anti-obesity effect with low dose and low toxicity can be obtained with the combinatory therapy applied by encapsulating the anti-obesity drug and gene in the same nanocarrier delivery vehicle.

Anti-obesity Properties of Phytochemicals: Highlighting their Molecular Mechanisms against Obesity

Obesity is a complex, chronic and inflammatory disease that affects more than one-third of the world's population, leading to a higher incidence of diabetes, dyslipidemia, metabolic syndrome, cardiovascular diseases, and some types of cancer. Several phytochemicals are used as flavoring and aromatic compounds, also exerting many benefits for public health. This study aims to summarize and scrutinize the beneficial effects of the most important phytochemicals against obesity. Systematic research of the current international literature was carried out in the most accurate scientific databases, e.g., Pubmed, Scopus, Web of Science and Google Scholar, using a set of critical and representative keywords, such as phytochemicals, obesity, metabolism, metabolic syndrome, etc. Several studies unraveled the potential positive effects of phytochemicals such as berberine, carvacrol, curcumin, quercetin, resveratrol, thymol, etc., against obesity and metabolic disorders. Mechanisms of action include inhibition of adipocyte differentiation, browning of the white adipose tissue, inhibition of enzymes such as lipase and amylase, suppression of inflammation, improvement of the gut microbiota, and downregulation of obesity-inducing genes. In conclusion, multiple bioactive compounds-phytochemicals exert many beneficial effects against obesity. Future molecular and clinical studies must be performed to unravel the multiple molecular mechanisms and anti-obesity activities of these naturally occurring bioactive compounds.

SCD1 is the critical signaling hub to mediate metabolic diseases: Mechanism and the development of its inhibitors

Metabolic diseases, featured with dysregulated energy homeostasis, have become major global health challenges. Patients with metabolic diseases have high probability to manifest multiple complications in lipid metabolism, e.g. obesity, insulin resistance and fatty liver. Therefore, targeting the hub genes in lipid metabolism may systemically ameliorate the metabolic diseases, along with the complications. Stearoyl-CoA desaturase 1(SCD1) is a key enzyme that desaturates the saturated fatty acids (SFAs) derived from de novo lipogenesis or diet to generate monounsaturated fatty acids (MUFAs). SCD1 maintains the metabolic and tissue homeostasis by responding to, and integrating the multiple layers of endogenous stimuli, which is mediated by the synthesized MUFAs. It critically regulates a myriad of physiological processes, including energy homeostasis, development, autophagy, tumorigenesis and inflammation. Aberrant transcriptional and epigenetic activation of SCD1 regulates AMPK/ACC, SIRT1/PGC1α, NcDase/Wnt, etc, and causes aberrant lipid accumulation, thereby promoting the progression of obesity, non-alcoholic fatty liver, diabetes and cancer. This review critically assesses the integrative mechanisms of the (patho)physiological functions of SCD1 in metabolic homeostasis, inflammation and autophagy. For translational perspective, potent SCD1 inhibitors have been developed to treat various types of cancer. We thus discuss the multidisciplinary advances that greatly accelerate the development of SCD1 new inhibitors. In conclusion, besides cancer treatment, SCD1 may serve as the promising target to combat multiple metabolic complications simultaneously.

The Commonly Used Stabilizers for Phytochemical-Based Nanoparticles: Stabilization Effects, Mechanisms, and Applications

Phytochemicals, such as resveratrol, curcumin, and quercetin, have many benefits for health, but most of them have a low bioavailability due to their poor water solubility and stability, quick metabolism, and clearance, which restricts the scope of their potential applications. To overcome these issues, different types of nanoparticles (NPs), especially biocompatible and biodegradable NPs, have been developed. NPs can carry phytochemicals and increase their solubility, stability, target specificity, and oral bioavailability. However, NPs are prone to irreversible aggregation, which leads to NP instability and loss of functions. To remedy this shortcoming, stabilizers like polymers and surfactants are incorporated on NPs. Stabilizers not only increase the stability of NPs, but also improve their characteristics. The current review focused on discussing the state of the art in research on synthesizing phytochemical-based NPs and their commonly employed stabilizers. Furthermore, stabilizers in these NPs were also discussed in terms of their applications, effects, and underlying mechanisms. This review aimed to provide more references for developing stabilizers and NPs for future research.

Development of Multifunctional Nanoencapsulated trans-Resveratrol/Chitosan Nutraceutical Edible Coating for Strawberry Preservation

Phytochemical nanoencapsulation for nutrient delivery and edible coatings for perishable food preservation are two emerging technologies. Leveraging the strong antimicrobial function of phytochemical nutrients, we propose convergent research to integrate the two technologies by embedding phytochemical-encapsulated nanoparticles in an edible coating on fresh fruits to achieve multiple functions. In particular, we report the study of an edible coating on strawberries that is composited of trans-resveratrol (R)-encapsulated nanoparticles (RNPs) embedded in a chitosan (CS) matrix. The biodegradable and biocompatible RNPs significantly increased the aqueous solubility of R by 150-fold and bioavailability by 3.5-fold after oral administration. Our results demonstrated the abilities of the RNP-embedded CS edible coating to diminish dehydration, prevent nutrient loss, inhibit microbe growth, increase nutraceutical value, preserve strawberry quality, and extend shelf life during storage at both 22 and 4 °C. Such a phytochemical nanoencapsulation-based edible coating is promising for the dual purposes of enhancing nutrient delivery and preserving perishable foods.

A critical review of RG-I pectin: sources, extraction methods, structure, and applications

In recent years, RG-I pectin isolated by low-temperature alkaline extraction methods has attracted the attention of a large number of researchers due to its huge health benefits. However, studies on other applications of RG-I pectin are still lacking. In this study, we summarized the sources (e.g. potato pulp, sugar beet pulp, okra, apple pomace, citrus peel, pumpkin, grapefruit, ginseng, etc.), extraction methods, fine structure and applications of RG-I pectin in physiological activities (e.g. anti-cancer, anti-inflammatory, anti-obesity, anti-oxidation, immune regulation, prebiotics, etc.), emulsions, gels, etc. These neutral sugar side chains not only endow RG-I pectin with various physiological activities but the entanglement and cross-linking of these side chains also endow RG-I pectin with excellent emulsifying and gelling properties. We believe that this review can not only provide a comprehensive reading for new workers interested in RG-I pectin, but also provide a valuable reference for future research directions of RG-I pectin.

5-HEPE reduces obesity and insulin resistance by promoting adipose tissue browning through GPR119/AMPK/PGC1α activation

AIMS

Activating thermogenic program in brown adipocytes serves as a potential therapeutic target for increasing energy expenditure during the treatment of metabolic diseases. 5(S)-hydroxy-eicosapentaenoic acid (5-HEPE), an omega-3 unsaturated fatty acid metabolite, has been shown to enhance insulin secretion in vitro. However, its role in modulating obesity-related diseases remains largely unclear.

MAIN METHODS

To investigate this further, mice were fed with a high-fat diet for 12 weeks and then injected intraperitoneally every other day with 5-HEPE for 4 additional weeks.

KEY FINDINGS

In vivo, our results demonstrated that 5-HEPE alleviated the HFD-induced obesity and insulin resistance, leading to a significant decrease in subcutaneous fat and epididymal fat index and an increase in brown fat index. Compared to the HFD group, the 5-HEPE group mice had lower ITT and GTT AUC and lower HOMA-IR. Moreover, 5HEPE effectively increased energy expenditure of mice. 5-HEPE also significantly promoted brown adipose tissue (BAT) activation and browning in white adipose tissue (WAT) by up-regulating genes and proteins expression of UCP1, Prdm16, Cidea, and PGC1α. In vitro, we found 5-HEPE significantly promoted 3T3-L1 browning. Mechanistically, 5-HEPE acts by activating the GPR119/AMPK/PGC1α pathway. In conclusion, this study emphasizes a critical role of 5-HEPE in improving body energy metabolism and adipose tissue browning in HFD-fed mice.

SIGNIFICANCE

Our results suggest that 5-HEPE intervention may be an effective target for preventing obesity-related metabolic diseases.

Nanocontroller-mediated dissolving hydrogel that can sustainably release cold-mimetic menthol to induce adipocyte browning for treating obesity and its related metabolic disorders

Obesity leads to the development of many metabolic diseases, causing severe health problems. Menthol can induce adipocyte browning and thus has been used to combat obesity. To deliver menthol with a sustained effect, an injectable hydrogel that comprises carboxymethyl chitosan and aldehyde-functionalized alginate that are crosslinked through dynamic Schiff-base linkages is developed to load menthol-cyclodextrin inclusion complexes (IC). To render the as-developed hydrogel soluble after its payload is released, amino acid-loaded liposomes, functioning as nanocontrollers, are covalently grafted onto networks of the hydrogel. Upon subcutaneous injection in mice with diet-induced obesity, the as-developed hydrogel absorbs body fluids and spontaneously swells, expanding and stretching its networks, gradually releasing the loaded IC. Menthol then disassociates from the released IC to induce adipocyte browning, triggering fat consumption and increasing energy expenditure. Meanwhile, the expanded hydrogel networks destabilize the grafted liposomes, which function as built-in nanocontrollers, unleashing their loaded amino acid molecules to disrupt the dynamic Schiff-base linkages, causing hydrogel to dissolve. The thus-developed nanocontroller-mediated dissolving hydrogel realizes the sustained release of menthol for treating obesity and its related metabolic disorders without leaving exogenous hydrogel materials inside the body, and thereby preventing any undesired adverse effects.

Targeted delivery of food functional ingredients in precise nutrition: design strategy and application of nutritional intervention

With the high incidence of chronic diseases, precise nutrition is a safe and efficient nutritional intervention method to improve human health. Food functional ingredients are an important material base for precision nutrition, which have been researched for their application in preventing diseases and improving health. However, their poor solubility, stability, and bad absorption largely limit their effect on nutritional intervention. The establishment of a stable targeted delivery system is helpful to enhance their bioavailability, realize the controlled release of functional ingredients at the targeted action sites in vivo, and provide nutritional intervention approaches and methods for precise nutrition. In this review, we summarized recent studies about the types of targeted delivery systems for the delivery of functional ingredients and their digestion fate in the gastrointestinal tract, including emulsion-based delivery systems and polymer-based delivery systems. The building materials, structure, size and charge of the particles in these delivery systems were manipulated to fabricate targeted carriers. Finally, the targeted delivery systems for food functional ingredients have gained some achievements in nutritional intervention for inflammatory bowel disease (IBD), liver disease, obesity, and cancer. These findings will help in designing fine targeted delivery systems, and achieving precise nutritional intervention for food functional ingredients on human health.

Nanostructured steady-state nanocarriers for nutrients preservation and delivery

Food bioactives possess specific physiological benefits of preventing certain diet-related chronic diseases or maintain human health. However, the limitations of the bioactives are their poor stability, lower water solubility and unacceptable bioaccessibility. Structure damage or degradation is often found for the bioactives under certain environmental conditions like high temperature, strong light, extreme pH or high oxygen concentration during food processing, packaging, storage and absorption. Nanostructured steady-state nanocarriers have shown great potential in overcoming the drawbacks for food bioactives. Various delivery systems including solid form delivery system, liquid form delivery system and encapsulation technology have been developed. The embedded food nutrients can largely decrease the loss and degradation during food processing, packaging and storage. The design and application of stimulus and targeted delivery systems can improve the stability, bioavailability and efficacy of the food bioactives upon oral consumption due to enzymatic degradation in the gastrointestinal tract. The food nutrients encapsulated in the smart delivery system can be well protected against degradation during oral administration, thus improving the bioavailability and releazing controlled or targeted release for food nutrients. The encapsulated food bioactives show great potential in nutrition therapy for sub-health status and disease. Much effort is required to design and prepare more biocompatible nanostructured steady-state nanocarriers using food-grade protein or polysaccharides as wall materials, which can be used in food industry and maintain the human health.

Modulating Inflammation-Mediated Diseases via Natural Phenolic Compounds Loaded in Nanocarrier Systems

The global increase and prevalence of inflammatory-mediated diseases have been a great menace to human welfare. Several works have demonstrated the anti-inflammatory potentials of natural polyphenolic compounds, including flavonoid derivatives (EGCG, rutin, apigenin, naringenin) and phenolic acids (GA, CA, etc.), among others (resveratrol, curcumin, etc.). In order to improve the stability and bioavailability of these natural polyphenolic compounds, their recent loading applications in both organic (liposomes, micelles, dendrimers, etc.) and inorganic (mesoporous silica, heavy metals, etc.) nanocarrier technologies are being employed. A great number of studies have highlighted that, apart from improving their stability and bioavailability, nanocarrier systems also enhance their target delivery, while reducing drug toxicity and adverse effects. This review article, therefore, covers the recent advances in the drug delivery of anti-inflammatory agents loaded with natural polyphenolics by the application of both organic and inorganic nanocarriers. Even though nanocarrier technology offers a variety of possible anti-inflammatory advantages to naturally occurring polyphenols, the complexes' inherent properties and mechanisms of action have not yet been fully investigated. Thus, expanding the quest on novel natural polyphenolic-loaded delivery systems, together with the optimization of complexes' activity toward inflammation, will be a new direction of future efforts.

Gold Nanobipyramid-Mediated Apoptotic Camouflage of Adipocytes for Obesity Immunotherapy

Obesity treatment is a global public health challenge due to inadequate weight loss and weight regain even after endeavors with multimodal treatments. Considering the abundance of resident macrophages in adipose tissues, precise regulation of the interactions between macrophages and adipocytes may provide chances for immunotherapy of obesity. Herein, inspired by the phagocytosis of macrophages to clear apoptotic cells in homeostasis, an immunotherapy strategy for obesity treatment is proposed for the first time through apoptotic camouflage of adipocytes by _PA Au BPs to activate macrophages for clearance, where _PA Au BPs are gold nanobipyramids engineered with adipose-targeting and apoptotic cell-mimicking functions. During clearance, the macrophage is switched from pro-inflammatory M1 to anti-inflammatory M2, remarkably modulating the immune microenvironment of adipose tissues to prevent weight regain. After inguinal injection with _PA Au BPs, the body weights of obese mice are effectively decreased by 24.4% and can be decreased by 33.3% when combined with photothermal lipolysis, and little weight regain is associated with these treatments. This study demonstrates that the strategy of camouflaging adipocytes with apoptotic features holds great potential for obesity immunotherapy.

Tackling Dyslipidemia in Obesity from a Nanotechnology Perspective

Obesity and dyslipidemia are the main features of metabolic syndrome, expressed mainly by adipose tissue dysfunction and connected by similar pathways and pharmacotherapy. Conventional drugs used in these two associated disorders are limited due to poor drug efficiency, non-specificity, and toxic side effects. Therefore, novel solutions for tackling obesity-associated diseases and providing insights into the development of innovative or improved therapies are necessary. Targeted nanotherapy is a revolutionary technology, offering a promising solution for combatting the disadvantages of currently available therapies for treating obesity and dyslipidemia due to its superior features, which include specific cell targeting, the protection of drugs against physiological degradation, and sustained drug release. This review presents a brief assessment of obesity and dyslipidemia, their impacts on human health, current treatment, and limitations, and the role and potential use of nanotechnology coupled with targeted drug delivery and nutraceuticals as emerging therapies. To the best of our knowledge, this paper presents, for the first time in the literature, a comparison between obesity and dyslipidemia nano-formulations based on drugs and/or natural extracts applied in experimental studies.

Biomaterial-Based Therapeutic Strategies for Obesity and Its Comorbidities

Obesity is a global public health issue that results in many health complications or comorbidities, including type 2 diabetes mellitus, cardiovascular disease, and fatty liver. Pharmacotherapy alone or combined with either lifestyle alteration or surgery represents the main modality to combat obesity and its complications. However, most anti-obesity drugs are limited by their bioavailability, target specificity, and potential toxic effects. Only a handful of drugs, including orlistat, liraglutide, and semaglutide, are currently approved for clinical obesity treatment. Thus, there is an urgent need for alternative treatment strategies. Based on the new revelation of the pathogenesis of obesity and the efforts toward the multi-disciplinary integration of materials, chemistry, biotechnology, and pharmacy, some emerging obesity treatment strategies are gradually entering the field of preclinical and clinical research. Herein, by analyzing the current situation and challenges of various new obesity treatment strategies such as small-molecule drugs, natural drugs, and biotechnology drugs, the advanced functions and prospects of biomaterials in obesity-targeted delivery, as well as their biological activities and applications in obesity treatment, are systematically summarized. Finally, based on the systematic analysis of biomaterial-based obesity therapeutic strategies, the future prospects and challenges in this field are proposed.

Nanomedicine of Plant Origin for the Treatment of Metabolic Disorders

Metabolic disorders are major clinical challenges of health that are progressing globally. A concurrence of metabolic disorders such as obesity, insulin resistance, atherogenic dyslipidemia, and systematic hypertension leads to metabolic syndrome. Over the past years, the metabolic syndrome leads to a five- and two-fold rise in diabetes mellitus type II and cardiovascular diseases. Natural products specifically plant extracts have insulin-sensitizing, anti-inflammatory, and antioxidant properties and are also considered as an alternative option due to few adverse effects. Nanotechnology is one of the promising strategies, which improves the effectiveness of treatment and limits side effects. This review mainly focuses on plant extract-based nanosystems in the management of the metabolic syndrome. Numerous nano-drug delivery systems, i.e., liposomes, hydrogel nanocomposites, nanoemulsions, micelles, solid lipid, and core–shell nanoparticles, have been designed using plant extracts. It has been found that most of the nano-formulations successfully reduced oxidative stress, insulin resistance, chronic inflammation, and lipid profile in in vitro and in vivo studies as plant extracts interfere with the pathways of metabolic syndrome. Thus, these novel plant-based nanosystems could act as a promising candidate for clinical applications.

A Review on Obesity Management through Natural Compounds and a Green Nanomedicine-Based Approach

Obesity is a serious health complication in almost every corner of the world. Excessive weight gain results in the onset of several other health issues such as type II diabetes, cancer, respiratory diseases, musculoskeletal disorders (especially osteoarthritis), and cardiovascular diseases. As allopathic medications and derived pharmaceuticals are partially successful in overcoming this health complication, there is an incessant need to develop new alternative anti-obesity strategies with long term efficacy and less side effects. Plants harbor secondary metabolites such as phenolics, flavonoids, terpenoids and other specific compounds that have been shown to have effective anti-obesity properties. Nanoencapsulation of these secondary metabolites enhances the anti-obesity efficacy of these natural compounds due to their speculated property of target specificity and enhanced efficiency. These nanoencapsulated and naive secondary metabolites show anti-obesity properties mainly by inhibiting the lipid and carbohydrate metabolizing enzymes, suppression of adipogenesis and appetite, and enhancing energy metabolism. This review focuses on the plants and their secondary metabolites, along with their nanoencapsulation, that have anti-obesity effects, with their possible acting mechanisms, for better human health.