Self-nanoemulsifying drug delivery system of trans-cinnamic acid: formulation development and pharmacodynamic evaluation in alloxan-induced type 2 diabetic rat model

Food Polyphenols and Type II Diabetes Mellitus: Pharmacology and Mechanisms

Type II diabetes mellitus and its related complications are growing public health problems. Many natural products present in our diet, including polyphenols, can be used in treating and managing type II diabetes mellitus and different diseases, owing to their numerous biological properties. Anthocyanins, flavonols, stilbenes, curcuminoids, hesperidin, hesperetin, naringenin, and phenolic acids are common polyphenols found in blueberries, chokeberries, sea-buckthorn, mulberries, turmeric, citrus fruits, and cereals. These compounds exhibit antidiabetic effects through different pathways. Accordingly, this review presents an overview of the most recent developments in using food polyphenols for managing and treating type II diabetes mellitus, along with various mechanisms. In addition, the present work summarizes the literature about the anti-diabetic effect of food polyphenols and evaluates their potential as complementary or alternative medicines to treat type II diabetes mellitus. Results obtained from this survey show that anthocyanins, flavonols, stilbenes, curcuminoids, and phenolic acids can manage diabetes mellitus by protecting pancreatic β-cells against glucose toxicity, promoting β-cell proliferation, reducing β-cell apoptosis, and inhibiting α-glucosidases or α-amylase. In addition, these phenolic compounds exhibit antioxidant anti-inflammatory activities, modulate carbohydrate and lipid metabolism, optimize oxidative stress, reduce insulin resistance, and stimulate the pancreas to secrete insulin. They also activate insulin signaling and inhibit digestive enzymes, regulate intestinal microbiota, improve adipose tissue metabolism, inhibit glucose absorption, and inhibit the formation of advanced glycation end products. However, insufficient data are available on the effective mechanisms necessary to manage diabetes.

Naturally-occurring carboxylic acids from traditional antidiabetic plants as potential pancreatic islet FABP3 inhibitors. A molecular docking-aided study

The antidiabetic action of traditional plants is mostly attributed to their antioxidant and anti-inflammatory properties. These plants are still having some secrets, making them an attractive source that allows for investigating new drugs or uncovering precise pharmacologic antidiabetic functions of their constituents. In diabetes, which is a lipid disease, long-term exposure of pancreatic islet beta cells to fatty acids (FAs) increases basal insulin release, reduces glucose-stimulated insulin secretion, causes islet beta cell inflammation, failure and apoptosis. Pancreatic islet beta cells express fatty acid binding protein 3 (FABP3) that receives long-chain FAs and traffics them throughout different cellular compartments to be metabolized and render their effects. Inhibition of this FABP3 may retard FA metabolism and protect islet beta cells. Since FAs interact with FABPs by their carboxylic group, some traditionally-known antidiabetic plants were reviewed in the present study, searching for their components that have common features of FABP ligands, namely carboxylic group and hydrophobic tail. Many of these carboxylic acids were computationally introduced into the ligand-binding pocket of FABP3 and some of them exhibited FABP3 ligand possibilities. Among others, the naturally occurring ferulic, cleomaldeic, caffeic, sinapic, hydroxycinnamic, 4-p-coumaroylquinic, quinoline-2-carboxylic, chlorogenic, 6-hydroxykynurenic, and rosmarinic acids in many plants are promising candidates for being FABP3-specific inhibitors. The study shed light on repurposing these phyto-carboxylic acids to function as FABP inhibitors. However, more in-depth biological and pharmacological studies to broaden the understanding of this function are needed.

Vitamin D3-Loaded Nanoemulsions as a Potential Drug Delivery System for Autistic Children: Formulation Development, Safety, and Pharmacokinetic Studies

The aim of the current study is the development of a vitamin D₃ (VD3)-loaded nanoemulsion (NE) formulation to improve VD3 oral bioavailability for management of vitamin D inadequacy in autistic children. Eight NE formulations were prepared by high-speed homogenization followed by ultrasonication. Four vegetable oils were employed along with two concentrations of Span 20 as the emulsifier. Glycerol, fructose, and mango flavor were included as viscosity modifier, sweetening, and flavoring agents, respectively. The prepared VD3-loaded NE formulations exhibited high drug content (> 98%), droplet size (DS) ranging from 61.15 to 129.8 nm with narrow size distribution, zeta potential values between - 9.83 and - 19.22 mV, and acceptable pH values (4.59-5.89). Storage stability showed that NE formulations underwent coalescence and phase separation during 6 months at room temperature, whereas at refrigerated conditions, formulations showed slight creaming. The optimum formulation (VD3-NE6) revealed a non-significant DS growth at refrigerated conditions and spherical morphology under transmission electron microscopy. VD3-NE6 did not produce any toxic effects to rats treated orally for 3 months, where normal blood picture and kidney and liver functions were observed compared to control rats. Also, serum calcium, oxidative stress, and apoptosis biomarkers remained within normal levels, indicating the safety of the optimum formulation. Furthermore, evaluation of VD3-NE6 oral bioavailability depicted a significant increase in AUC_0-72 and C_max with decreased T_max compared to plain VD3. The optimum formulation demonstrated improved stability, safety, and oral bioavailability indicating the potential for successful management of vitamin D deficiency in autistic children.

The Trend of Organic Based Nanoparticles in the Treatment of Diabetes and Its Perspectives

Diabetes is an untreatable metabolic disorder characterized by alteration in blood sugar homeostasis, with submucosal insulin therapy being the primary treatment option. This route of drug administration is attributed to low patient comfort due to the risk of pain, distress, and local inflammation/infections. Nanoparticles have indeed been suggested as insulin carriers to allow the drug to be administered via less invasive routes other than injection, such as orally or nasally. The organic-based nanoparticles can be derived from various organic materials (for instance, polysaccharides, lipids, and so on) and thus are prevalently used to enhance the physical and chemical consistency of loaded bioactive compounds (drug) and thus their bioavailability. This review presents various forms of organic nanoparticles (for example, chitosan, dextron, gums, nanoemulsion, alginate, and so on) for enhanced hypoglycemic drug delivery relative to traditional therapies.

Investigating the Impact of Optimized Trans-Cinnamic Acid-Loaded PLGA Nanoparticles on Epithelial to Mesenchymal Transition in Breast Cancer

Purpose

Methods

Results

Conclusion

Selected 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors. A look into their use and potential in pre-diabetes and type 2 diabetes

Objectives. This review assesses the comparative safety and efficacy of selected 3-hydroxy-3-methylglutaric acid coenzyme A inhibitors (statins, cinnamic acids. 3-hydroxy-3-methyl glutaric acid) on the pre-onset type 2 diabetes (PT2D) and post-onset type 2 diabetes (T2D)-related cluster of seven features (central obesity, hyperglycemia, hypertension, dyslipidemia, pro-thrombosis, oxidation and inflammation). Methods. Google scholar and PubMed were searched for statin*, flaxseed lignan complex (FLC), cinnamic acid (CA)*, and 3-hydroxy-3-methylglutaric acid (HMGA) in conjunction with each of PT2D, T2D and the cluster of seven. An introduction was followed by findings or absence thereof on the impacts of each of statins, FLC, CAs and HMGA on each member of the cluster of seven. Results. Pravastatin manages three features in PT2D, while a number of the statins improve five in T2D. FLC is negative in PT2D but controls four in T2D; it is not clear if the CAs and HMGA in FLC play a role in this success. CAs have potential in six and HMGA has potential in three of the cluster of seven though yet CAs and HMGA are untested in PT2D and T2D in humans. There are safety concerns with some statins and HMGA but FLC and CAs appear safe in the doses and durations tested. Conclusions. Selected statins, FLC, CAs and HMGA can manage or have a potential to manage at least three features of the cluster of seven. Most of the literature-stated concerns are with select statins but there are concerns (one actual and two potential) with HMGA.

Cinnamic Acid Ameliorates Nonalcoholic Fatty Liver Disease by Suppressing Hepatic Lipogenesis and Promoting Fatty Acid Oxidation

BACKGROUND

Cinnamic acid (CA) has been shown to have many beneficial effects including regulating lipid metabolism and reducing obesity. However, its effect on nonalcoholic fatty liver disease (NAFDL) has not been investigated in detail. Thus, we performed this study in order to explore CA's effect on hepatic lipid metabolism and the underlying mechanisms.

METHOD

Oleic acid (OA) was used to induce lipid accumulation in HepG2 cells. After coincubation with CA, the cells were stained with oil red O and the triglyceride (TG) content was assessed. Key genes in lipogenesis and fatty acid oxidation pathways were tested. Additionally, db/db and wt/wt mice were divided into three groups, with the wt/wt mice representing the normal group and the db/db mice being divided into the NAFLD and CA groups. After 4 weeks of oral treatment, all mice were sacrificed and the blood lipid profile and liver tissues were assessed.

RESULTS

CA treatment reduced the lipid accumulation in HepG2 cells and in db/db mouse livers. ACLY, ACC, FAS, SCD1, PPARγ, and CD36 were significantly downregulated, while CPT1A, PGC1α, and PPARα were significantly upregulated.

CONCLUSION

CA's therapeutic effect on NAFLD may be attributed to its ability to lower hepatic lipid accumulation, which is mediated by suppression of hepatic lipogenesis and fatty acid intake, as well as increased fatty acid oxidation.

Preparation and evaluation of oral self-microemulsifying drug delivery system of Chlorophyll

OBJECTIVE

This study was aimed at improving the water solubility and oral bioavailability of Chl by self-microemulsifying drug delivery system (Chl-SMEDDS).

METHODS

Compatibility experiments, pseudo-ternary phase diagram and central composite design were used to optimize the formulation. The selected systems were further evaluated for physical characteristics, including particle size, zeta potential, and appearance. The stability, in vitro dispersion test, and in vivo intestinal perfusion experiments were used to evaluate the SMEDDS.

RESULTS

The optimal composition of Chl-SMEDDS included: Labrafil M 1944 CS (35%), kolliphor RH 40 (46%), Transcutol HP (19%) and 60 mg/g Chl. The appearance of water emulsified Chl-SMEDDS was green and transparent. The particle size, ζ-potential, and transmission electron microscopy studies showed that spherical globules of Chl-SMEDDS with a size of about 22.82 ± 1.29 nm and a negative surface charge of -24.21 ± 3.45 mV were obtained. Chl-SMEDDS could remain stable at 25 °C and 4 °C for at least 6 months. The dispersion test showed that Chl-SMEDDS dispersed spontaneously to form microemulsion after disintegration of capsule shell and 90% drug dispersed in just 30 min in pH 1.2 HCl without any drug precipitation during the test period. In vivo intestinal perfusion experiment revealed that the main absorption site for Chl-SMEDDS was duodenum.

CONCLUSIONS

This study indicates that SMEDDS formulation could be an effective strategy for the oral administration of Chl.

Phytotherapeutic potential of bi-herbal extract of cinnamon and turmeric: in vivo antidiabetic studies

Background

The spices, cinnamon and turmeric have both culinary and pharmaceutical applications. Earlier studies proved their effect on reducing the symptoms associated with type 2 diabetes, a major lifestyle disease affecting millions world over. In our work, we prepared a bi-herbal extract of cinnamon and turmeric and studied its effect to alleviate the symptoms of type 2 diabetes in rat model.

Method

The phenolic rich bi-herbal extract was given to diabetes induced male wistar rats for 28 days at two different concentrations (50 and 150 mg/Kg bwt.). The changes in blood glucose level were monitored at weekly interval. At the end of the experiment, blood serum was collected and used for the estimation of lipid profile, Glucose, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), Total Protein (TP), Albumin, Urea and Creatinine levels.

Result

The serum analysis revealed that administration of the bi-herbal extract at 150 mg/Kg bwt. significantly reduced the blood glucose level (152.60 ± 40.2 mg/dL; p < 0.05) of diabetic animals as compared to diabetic control (335.40 ± 67.3 mg/dL; p < 0.05) at the end of 4 weeks. The treatment also resulted in the reduction of total cholesterol and LDL-cholestrol levels as compared to diabetic control animals. The histopathological examination of tissues showed the improvement in pancreatic architecture and restoration of tissue integrity in liver and kidney.

Conclusion

The study concludes that methanol extract of combination of cinnamon and turmeric has good hypoglycemic, hypolipidemic and organ protective potential in diabetic rats which could be developed into functional food supplementation for the prevention of type 2 diabetes.

Improvement of Oral Bioavailability and Anti-Tumor Effect of Zingerone Self-Microemulsion Drug Delivery System

This study sought to prepare a self-microemulsion drug delivery system containing zingerone (Z-SMEDDS) to improve the low oral bioavailability of zingerone and anti-tumor effect. Z-SMEDDS was characterized by particle size, zeta potential and encapsulation efficiency, while its pharmacokinetics and anti-tumor effects were also evaluated. Z-SMEDDS had stable physicochemical properties, including average particle size of 17.29 ± 0.07 nm, the zeta potential of -22.81 ± 0.29 mV, and the encapsulation efficiency of 97.96% ± 0.02%. In vitro release studies have shown the release of zingerone released by Z-SMEDDS was significantly higher than free zingerone in different release media. The relative oral bioavailability of Z-SMEDDS was 7.63 times compared with free drug. Meanwhile, the half inhibitory concentration （IC50）of Z-SMEDDS and free zingerone was 8.45 μg/mL and 13.30 μg/mL, respectively on HepG2. This study may provide a preliminary basis for further clinical research and application of Z-SMEDDS.

Improved Oral Bioavailability and Hypolipidemic Effect of Syringic Acid via a Self-microemulsifying Drug Delivery System

This study aimed to develop a self-microemulsifying drug delivery system (SMEDDS) to enhance the solubility, oral bioavailability, and hypolipidemic effects of syringic acid (SA), a bioactive and poorly-soluble polyphenol. Based on the response surface methodology-central composite design (RSM-CCD), an optimum formulation of SA-SMEDDS, consisting of ethyl oleate (oil, 12.30%), Cremophor-EL (surfactant, 66.25%), 1,2-propanediol (cosurfactant, 21.44%), and drug loading (50 mg/g), was obtained. The droplets of SA-SMEDDS were nanosized (16.38 ± 0.12 nm), spherically shaped, and homogeneously distributed (PDI = 0.058 ± 0.013) nanoparticles with high encapsulation efficiency (98.04 ± 1.39%) and stability. In vitro release study demonstrated a prolonged and controlled release of SA from SMEDDS. In vitro cell studies signified that SA-SMEDDS droplets substantially promoted cellular internalization. In comparison with the SA suspension, SA-SMEDDS showed significant prolonged T_max, t_1/2, and MRT after oral administration. Also, SA-SMEDDS exhibited a delayed in vivo elimination, increased bioavailability (2.1-fold), and enhanced liver accumulation. Furthermore, SA-SMEDDS demonstrated significant improvement in alleviating serum lipid profiles and hepatic steatosis in high-fat diet-induced hyperlipidemia in mice. Collectively, SMEDDS demonstrated potential as a nanosystem for the oral delivery of SA with enhanced bioavailability and hypolipidemic effects.

Oral Nano Drug Delivery Systems for the Treatment of Type 2 Diabetes Mellitus: An Available Administration Strategy for Antidiabetic Phytocompounds

In view of the worldwide serious health threat of type 2 diabetes mellitus (T2DM), natural sources of chemotherapies have been corroborated as the promising alternatives, with the excellent antidiabetic activities, bio-safety, and more cost-effective properties. However, their clinical application is somewhat limited, because of the poor solubility, instability in the gastrointestinal tract (GIT), low bioavailability, and so on. Nowadays, to develop nanoscaled systems has become a prominent strategy to improve the drug delivery of phytochemicals. In this review, we primarily summarized the intervention mechanisms of phytocompounds against T2DM and presented the recent advances in various nanosystems of antidiabetic phytocompounds. Selected nanosystems were grouped depending on their classification and structures, including polymeric NPs, lipid-based nanosystems, vesicular systems, inorganic nanocarriers, and so on. Based on this review, the state-of-the-art nanosystems for phytocompounds in T2DM treatment have been presented, suggesting the preponderance and potential of nanotechnologies.

Self-Nano-Emulsifying Drug-Delivery Systems: From the Development to the Current Applications and Challenges in Oral Drug Delivery

Approximately one third of newly discovered drug molecules show insufficient water solubility and therefore low oral bio-availability. Self-nano-emulsifying drug-delivery systems (SNEDDSs) are one of the emerging strategies developed to tackle the issues associated with their oral delivery. SNEDDSs are composed of an oil phase, surfactant, and cosurfactant or cosolvent. SNEDDSs characteristics, their ability to dissolve a drug, and in vivo considerations are determinant factors in the choice of SNEDDSs excipients. A SNEDDS formulation can be optimized through phase diagram approach or statistical design of experiments. The characterization of SNEDDSs includes multiple orthogonal methods required to fully control SNEDDS manufacture, stability, and biological fate. Encapsulating a drug in SNEDDSs can lead to increased solubilization, stability in the gastro-intestinal tract, and absorption, resulting in enhanced bio-availability. The transformation of liquid SNEDDSs into solid dosage forms has been shown to increase the stability and patient compliance. Supersaturated, mucus-permeating, and targeted SNEDDSs can be developed to increase efficacy and patient compliance. Self-emulsification approach has been successful in oral drug delivery. The present review gives an insight of SNEDDSs for the oral administration of both lipophilic and hydrophilic compounds from the experimental bench to marketed products.

Enhanced oral bioavailability of Bisdemethoxycurcumin-loaded self-microemulsifying drug delivery system: Formulation design, in vitro and in vivo evaluation

In this study, we sought to overcome the poor solubility and bioavailability of bismethoxycurcumin (BDMC) by fabricating a BDMC-loaded self micro-emulsifying system (BDMC-SMEDDS). Solubility and compatibility tests, pseudo-ternary phase diagrams (PTPDs) as well as d-optimal concept was applied to design the formulation. The assessment of the prepared BDMC-SMEDDS in-vitro mainly included droplet size (DS) and entrapment efficiency (EE) determination, morphology, drug release and stability testing. Besides, the in vivo behavior was also evaluated after oral administration of BDMC-SMEDDS to rats. The optimal formulation was found to compose of Kolliphor EL (K-EL, emulsifier, 645.3 mg), PEG 400 (co-emulsifier, 147.2 mg), ethyl oleate (EO, oil, 207.5 mg) and BDMC (50 mg). The BDMC-SMEDDS with satisfactory stability had a mean size of 21.25 ± 3.23 nm and EE of 98.31 ± 0.32%. Roughly 70% of BDMC was released from BDMC-SMEDDS within 84 h compared with <20% from the free BDMC. More importantly, the in-vivo behavior of BDMC-SMEDDS showed that the AUC_(0-12h) and plasma concentration of BDMC increased substantially as compared to the free BDMC. Altogether, BDMC-SMEDDS has the potential to enhance the solubility and bioavailability of BDMC and could be applied in the clinics.

Improved hepatoprotective activity of Beta vulgaris L. leaf extract loaded self-nanoemulsifying drug delivery system (SNEDDS): in vitro and in vivo evaluation

OBJECTIVE

Beta vulgaris L. (beetroot) is a vegetable plant rich in phytochemical compounds such as phenolic acids, carotenoids and flavonoids. The objective of the current study is the development and optimization of self-nanoemulsifying drug delivery systems (SNEDDSs) to enhance the hepatoprotective activity of beet leaf (BL) extract.

METHODS

Total flavonoids content was estimated in the BL extract and its solubility was evaluated in various vehicles to select proper component combinations. Pseudo-ternary phase diagrams were constructed employing olive, linseed, castor and sesame oils (oil phase), Tween^® 20 (Tw20) and Tween^® 80 (Tw80) (surfactants (SAs)) as well as dimethyl sulfoxide (DMSO) and propylene glycol (PG) (co-surfactants (Co-SAs)). Optimization of formulations from the phase diagrams took place through testing their thermodynamic stability, dispersibility and robustness to dilution.

RESULTS

Four optimized BL-SNEDDS formulations, comprising linseed oil or olive oil, Tw80 and DMSO at two SA/Co-SA ratios (2:1 or 3:1) were chosen. They exhibited high cloud point and percentage transmittance values with spherical morphology of mean droplet sizes ranging from 14.67 to 16.06 nm and monodisperse distribution with negatively charged zeta potential < -9.51 mV. The in vitro release profiles of the optimized formulations in pH 1.2 and 6.8 were nearly similar, with a non-Fickian release mechanism. In vivo evaluation of BL-SNEDDSs hepatoprotective activity in a thioacetamide-induced hepatotoxicity rat model depicted promoted liver functions, inflammatory markers and histopathological findings, most prominently in the group treated by F7.

CONCLUSION

The results indicate that SNEDDS, as a nanocarrier system, has potential to improve the hepatoprotective activity of the BL extract.

Dietary quinoa (Chenopodium quinoa Willd.) polysaccharides ameliorate high-fat diet-induced hyperlipidemia and modulate gut microbiota

As the high nutritional and functional values of quinoa acknowledged, the increasing researches focus on the bioactivities and related mechanisms of its abundant carbohydrates. Herein, the beneficial effects of the soluble polysaccharide fraction from quinoa was investigated to lower the serum lipid of rats treated by high-fat diet (HFD) and call the disordered gut microbiota back. The polysaccharide faction was firstly extracted by ultrasonic-assisted extraction technology (yield of 9.65%) and characterized of the monosaccharide composition with glucose and arabinose (1.17:1, molar ratio). And then, the oral administration of quinoa polysaccharide of 300 mg·kg^-1·day^-1 and 600 mg·kg^-1·day^-1 for 8 weeks remarkably alleviated dyslipidemia by decreasing the levels of serum total triglyceride (TG), low density lipoprotein cholesterol (LDL-C), malondialdehyde (MDA), total glutamic pyruvic transaminase (ALT) and glutamic oxaloacetic transaminase (AST) in rats fed with HFD, as well as the reduced hepatic lipid accumulation. Meanwhile, the relative abundance of gut microbiota could be disordered by the long term of HFD. Nevertheless, dietary supplementation of quinoa polysaccharide could enhance species richness and regulate the gut microbiota community structure, reducing the ratio of Firmicutes and Bacteroides, the relative abundance of Proteobacteria. Meanwhile, Sequencing of 16S rRNA gene revealed that intake of quinoa polysaccharide decreased the relative abundances of Desulfovibrio and Allobaculum, which were positively correlated with serum lipid profiles and beneficial to lessen intestinal inflammation. Taken together, the present study demonstrated that quinoa polysaccharide supplementation could ameliorate the hyperlipidemia induced by HFD in association with modulating gut microbiota in a positive way.

The polypharmacy reduction potential of cinnamic acids and some related compounds in pre- and post-onset management of type 2 diabetes mellitus

Objectives. This review assesses the polypharmacy reduction potential of cinnamic acids (CAs) and some related compounds in managing three or more of the cluster of seven, pre- and post-type 2 diabetes mellitus (T2DM)-related features (central obesity, hyperglycemia, hypertension, dyslipidemia, pro-thrombosis, oxidation, and inflammation).

Methods. Google scholar and Pubmed were searched for cinnam*, chlorogenic acid, ferulic acid, and caffeic acid in conjunction with each of pre- and post-onset T2DM, central obesity, hyperglycemia, hypertension, dyslipidemia, pro-thrombosis, oxidation, and inflammation. The study was divided into an introduction followed by findings on the impacts of each of the CAs including trans-CA acid, the E isomer of a CA-based thiazolidinedione and a metabolite of that isomer, as well as p-methoxy CA, various cinnamic amides and some other CA-related compounds (chlorogenic acid, cinnamaldehyde, ferulic and caffeic acid).

Results. Trans-CA has a potential to manage three, while each of chlorogenic acid, cinnamalde-hyde, caffeic acid and ferulic acid has a potential to manage all seven members of the cluster. Other CA-related compounds identified may manage only one or two of the cluster of seven.

Conclusions. Much of the work has been done in animal models of pre- and post-onset T2DM and non-pre- or post-onset T2DM humans and animals, along with some cell culture and in vitro work. Very little work has been done with human pre- and post-onset T2DM. While there is potential for managing 3 or more members of the cluster with many of these compounds, a definitive answer awaits large pre- and post-T2DM onset clinical trials with humans.

Plant-Based Antidiabetic Nanoformulations: The Emerging Paradigm for Effective Therapy

Diabetes mellitus is a life-threatening metabolic syndrome. Over the past few decades, the incidence of diabetes has climbed exponentially. Several therapeutic approaches have been undertaken, but the occurrence and risk still remain unabated. Several plant-derived small molecules have been proposed to be effective against diabetes and associated vascular complications via acting on several therapeutic targets. In addition, the biocompatibility of these phytochemicals increasingly enhances the interest of exploiting them as therapeutic negotiators. However, poor pharmacokinetic and biopharmaceutical attributes of these phytochemicals largely restrict their clinical usefulness as therapeutic agents. Several pharmaceutical attempts have been undertaken to enhance their compliance and therapeutic efficacy. In this regard, the application of nanotechnology has been proven to be the best approach to improve the compliance and clinical efficacy by overturning the pharmacokinetic and biopharmaceutical obstacles associated with the plant-derived antidiabetic agents. This review gives a comprehensive and up-to-date overview of the nanoformulations of phytochemicals in the management of diabetes and associated complications. The effects of nanosizing on pharmacokinetic, biopharmaceutical and therapeutic profiles of plant-derived small molecules, such as curcumin, resveratrol, naringenin, quercetin, apigenin, baicalin, luteolin, rosmarinic acid, berberine, gymnemic acid, emodin, scutellarin, catechins, thymoquinone, ferulic acid, stevioside, and others have been discussed comprehensively in this review.

WS2 nanosheets functionalized by biomimetic lipids with enhanced dispersibility for photothermal and chemo combination therapy

A WS₂-lipid nanocarrier with enhanced stability and intratumoral accumulation was synthesized for photothermal-chemo combination therapy

Improving The Oral Absorption Of Nintedanib By A Self-Microemulsion Drug Delivery System: Preparation And In Vitro/In Vivo Evaluation

OBJECTIVE

Nintedanib (NDNB) is a triple receptor tyrosine kinase inhibitor with poor solubility in neutral conditions and low bioavailability. A self-microemulsifying drug delivery system (SMEDDS) of NDNB was developed to improve drug solubility in physical conditions and absorption in vivo.

METHODS

The NDNB-SMEDDS formulation was optimized via pseudo-ternary phase diagrams. The physicochemical properties of NDNB-SMEDDS, viz., morphological observation, droplet size, stability, compatibility and in vitro release were investigated. The permeability of NDNB-SMEDDS was detected using both a Caco-2 cell monolayer in vitro and an intestinal perfusion study in vivo. Furthermore, the pharmacokinetic characteristics of NDNB-SMEDDS were evaluated.

RESULTS

The optimal formulation was composed of MCT as an oil phase, RH 40 as a surfactant and ethylene glycol as a co-surfactant. The average droplet size of the microemulsion was about 23 nm with good stability within 30 days. The formulation did not exhibit any obvious cytotoxic effect on Caco-2 cells. Permeability of nintedanib in a Caco-2 cell monolayer was enhanced by 2.8-fold upon incorporation in SMEDDS compared with the drug solution. The intestinal perfusion study demonstrated that the P app of NDNB-SMEDDS increased by 3.0-fold in the entire intestine and 3.2-fold in the colon in comparison with the drug solution. The pharmacokinetics study showed that the AUC of the NDNB-SMEDDS increased significantly.

CONCLUSION

This study showed that the self-microemulsion formulations could improve the absorption of nintedanib, and can thus serve as a promising carrier for the oral delivery of nintedanib.

Novel cuminaldehyde self-emulsified nanoemulsion for enhanced antihepatotoxicity in carbon tetrachloride-treated mice

Objectives

Cuminaldehyde self-emulsified nanoemulsion (CuA-SEN) was prepared and optimised to improve its oral bioavailability and antihepatotoxicity.

Methods

Cuminaldehyde self-emulsified nanoemulsion was developed through the self-nanoemulsification method using Box–Behnken Design (BBD) tool while appropriate physicochemical indices were evaluated. The optimised CuA-SEN was characterised via droplet size (DS), morphology, polydispersity index (PDI), zeta potential (ZP), entrapment efficiency, in-vitro release, and pharmacokinetic studies while its antihepatotoxicity was evaluated.

Key findings

Cuminaldehyde self-emulsified nanoemulsion with acceptable characteristics (mean DS-48.83 ± 1.06 nm; PDI-0.232 ± 0.140; ZP-29.92 ± 1.66 mV; EE-91.51 ± 0.44%; and drug-loading capacity (DL)-9.77 ± 0.75%) was formulated. In-vitro drug release of CuA-SEN significantly increased with an oral relative bioavailability of 171.02%. Oral administration of CuA-SEN to CCl4-induced hepatotoxicity mice markedly increased the levels of superoxide dismutase, glutathione and catalase in serum. Also, CuA-SEN reduced the levels of tumour necrosis factor-alpha and interleukin-6 in both serum and liver tissues while aspartate aminotransferase, alanine aminotransferase and malonaldehyde levels were significantly decreased.

Conclusions

These findings showed that the improved bioavailability of cuminaldehyde via SEN provided an effective approach for enhancing antioxidation, anti-inflammation and antihepatotoxicity of the drug.

Bibliometric analysis of research on the role of intestinal microbiota in obesity

BACKGROUND

Obesity is a key public health problem. The advancement of gut microbiota research sheds new light on this field. This article aims to present the research trends in global intestinal microbiota studies within the domain of obesity research.

METHODS

Bibliographic information of the publications on intestinal microbiota and obesity was retrieved from the Scopus database, and then analyzed by using bibliometric approaches.

RESULTS

A total of 3,446 references were retrieved; the data indicated a steady growth and an exponential increase in publication numbers. The references were written in 23 different languages (93.8% in English). A number of 3,056 English journal papers were included in the further analyses. Among the 940 journals, the most prolific ones were PLOS ONE, Scientific Reports, and British Journal of Nutrition. North America and Europe were the highest publication output areas. The US (995 publications) ranked first in the number of publications, followed by the China (243 publications) and France (242 publications). The publication numbers were significantly correlated with gross domestic product (GDP), human development index (HDI), and population number (PN). International collaboration analysis also shows that most of the collaborations are among developed countries.

DISCUSSION

This comprehensive bibliometric study indicates that gut microbiota is a significant topic in the obesity research. The structured information may be helpful in understanding research trends, and locating research hot spots and gaps in this domain.

Cinnamic Acid and Its Derivatives: Mechanisms for Prevention and Management of Diabetes and Its Complications

With recent insight into the development of dietary supplements and functional foods, search of effective phytochemical compounds and their mechanisms involved in prevention and management of diabetes and its complications are now being assessed. Cinnamic acid and its derivatives occur naturally in high levels of plant-based foods. Among various biological activities, cinnamic acid and its derivatives are associated with a beneficial influence on diabetes and its complications. The aim of the review is to summarize the potential mechanisms of these compounds for prevention and management of diabetes and its complications. Based on several in vitro studies and animal models, cinnamic acid and its derivatives act on different mechanism of actions, including stimulation of insulin secretion, improvement of pancreatic β-cell functionality, inhibition of hepatic gluconeogenesis, enhanced glucose uptake, increased insulin signaling pathway, delay of carbohydrate digestion and glucose absorption, and inhibition of protein glycation and insulin fibrillation. However, due to the limited intestinal absorption being a result of low bioavailability of cinnamic acid and its derivatives, current improvement efforts with entrapping into solid and liquid particles are highlighted. Further human clinical studies are needed to clarify the effects of cinnamic acid and its derivatives in diabetic patients.

Tissue distribution and enhanced in vivo anti-hyperlipidemic-antioxidant effects of perillaldehyde-loaded liposomal nanoformulation against Poloxamer 407-induced hyperlipidemia

An optimized perillaldehyde-loaded liposomal nanoformulation (PAH-LNF) was successfully applied to improve the pharmacological effect of perillaldehyde (PAH) in poloxamer 407-induced hyperlipidemia. Oral administration of PAH-LNF (240mg/kg per body weight) in rats significantly enhanced solubility and relative bioavailability (270.7%) compared to the free PAH with about 2.7-, 1.5-, 1.3-, 1.3- and 1.5-fold increase in AUC, T_1/2, MRT, C_max and T_max, respectively. Tissue distribution study also revealed the accumulation of PAH in the liver, lungs, spleen, kidney, brain and heart in order of decreasing affinity. Moreover, a significant decrease in serum total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) with simultaneous increase in high-density lipoprotein cholesterol (HDL-C) level was observed in the chemically-induced hyperlipidemic mice which further confirmed PAH's anti-hyperlipidemic properties. Additionally, PAH-LNF also significantly increased the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) with a concurrent decrease in malondialdehyde (MDA) to affirm the antioxidant and hepatoprotective effects of PAH. Thus, liposomal nanoformulation promises to be a useful drug delivery system for the development of PAH.

Hypolipidemic potential of perillaldehyde-loaded self-nanoemulsifying delivery system in high-fat diet induced hyperlipidemic mice: Formulation, in vitro and in vivo evaluation

This study reports the hypolipidemic effects of perillaldehyde-loaded self-nanoemulsifying delivery system (PAH-SNEDS) developed with D-optimal experimental design based on a three component system: 40% w/w drug-oil phase, X1 (a mixture of perillaldehyde-isopropyl myristate/medium chain triglyceride, 1:1, w/w); 48% surfactant, X2 (Kolliphor EL); and 12% co-surfactant, X3 (PEG 200). The design space was navigated using a linear model to produce spherical and homogenous droplets which were observed under TEM, with mean size, polydispersity index (PDI) and zeta potential of 32.8 ± 0.1 nm, 0.270 ± 0.029 and -10.14 ± 0.66 mV, respectively. PAH-SNEDS demonstrated significant increase in dissolution in vitro compared to the free PAH, and further yielded an oral relative bioavailability of about 206.18% in vivo which suggested a promising formulation design for potential liquid bioactive compounds. Oral administration of PAH-SNEDS (240 mg/kg per body weight) in high-fat induced hyperlipidemia in mice, also significantly decreased serum total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) while increasing high-density lipoprotein cholesterol (HDL-C) level. The improved bioavailability and functional application of PAH via SNEDDS suggested a suitable approach to promote hypolipidemic effect of the drug. Perillaldehyde, therefore, promises to be a useful bioactive compound to prevent high-fat diet induced hyperlipidemia.

Antidiabetic Effects of Simple Phenolic Acids: A Comprehensive Review

Diabetes mellitus (DM) has become a major public health threat across the globe. Current antidiabetic therapies are based on synthetic drugs that very often have side effects. It has been widely acknowledged that diet plays an important role in the management of diabetes. Phenolic acids are widely found in daily foods such as fruits, vegetables, cereals, legumes, and wine and they provide biological, medicinal, and health properties. Simple phenolic acids have been shown to increase glucose uptake and glycogen synthesis, improve glucose and lipid profiles of certain diseases (obesity, cardiovascular diseases, DM, and its complication). The current review is an attempt to list out the antidiabetic effects of simple phenolic acids from medicinal plants and botanical foods.

Formulation design and in vitro physicochemical characterization of surface modified self-nanoemulsifying formulations (SNEFs) of gentamicin

Self-nanoemulsifying formulations (SNEFs) structured with PEG 4000 as PEGylated SNEFs, were formulated after solubility studies using rational blends of soybean oil, a combination of Kolliphor(®) EL and Kolliphor(®) P188 as surfactants, and Transcutol(®) HP as co-surfactant, and evaluated for oral delivery of gentamicin. Incorporation of gentamicin and PEG 4000 reduced the initial area of nanoemulsion of the ternary phase diagrams produced by water titration method using oil, surfactant mixture and co-surfactant. Emulsion droplets were in the nanometer scale ranging from 80-210 nm. FT-IR study revealed that gentamicin structure remained intact in all formulations, and SEM micrographs showed spherical globules. Zeta potentials of SNEFs were in the range of -25.4 to -42.5 mV, and showed a stable system with minor flips in electrostatic charges. There was high in vitro diffusion-dependent permeation of gentamicin from the SNEFs. Results obtained in this work showed that oral delivery of gentamicin was improved by formulation as surface modified SNEFs.

Thiomorpholine Derivatives with Hypolipidemic and Antioxidant Activity

A number of thiomorpholine derivatives that are structurally similar to some substituted morpholines possessing antioxidant and hypocholesterolemic activity were synthesized. The new compounds incorporate an antioxidant moiety as the thiomorpholine N-substituent. The derivatives were found to inhibit the ferrous/ascorbate-induced lipid peroxidation of microsomal membrane lipids, with IC50 values as low as 7.5 µΜ. In addition, these compounds demonstrate hypocholesterolemic and hypolipidemic action. The most active compound (5) decreases the triglyceride, total cholesterol, and low-density lipoprotein levels in the plasma of Triton WR-1339-induced hyperlipidemic rats, by 80, 78, and 76%, respectively, at 56 mmol/kg (i.p.). They may also act as squalene synthase inhibitors. The above results indicate that the new molecules may be useful as leads for the design of novel compounds as potentially antiatherogenic factors.