Dramatic improvement in pharmacokinetic and pharmacodynamic effects of sustain release curcumin microparticles demonstrated in experimental type 1 diabetes model

Curcumin Nanoemulsion: Unveiling Cardioprotective Effects via ACE Inhibition and Antioxidant Properties in Hypertensive Rats

Background and Objectives: Curcumin, derived from Curcuma longa, is a well-known traditional medicinal compound recognized for its therapeutic attributes. Nevertheless, its efficacy is hampered by limited bioavailability, prompting researchers to explore the application of nanoemulsion as a potential alternative. Materials and Methods: This study delves into the antihypertensive effects of curcumin nanoemulsion (SNEC) by targeting the renin-angiotensin-aldosterone system (RAAS) and oxidative stress in deoxycorticosterone acetate (DOCA) salt-induced hypertensive rats. To gauge the cardio-protective impact of SNEC in DOCA salt-induced hypertension, molecular docking was undertaken, uncovering curcumin's high affinity and adept binding capabilities to the active site of angiotensin-converting enzyme (ACE). Additionally, the investigation employed uninephrectomized rats to assess hemodynamic parameters via an AD instrument. Serum ACE, angiotensin II, blood urea nitrogen (BUN), and creatinine levels were quantified using ELISA kits, while antioxidant parameters were evaluated through chemical assays. Result: The outcomes of the molecular docking analysis revealed robust binding of curcumin to the ACE active site. Furthermore, oral administration of SNEC significantly mitigated systolic, diastolic, and mean arterial blood pressure in contrast to the DOCA-induced hypertensive group. SNEC administration also led to a reduction in left ventricular end-diastolic pressure (LVEDP) and an elevation in the maximum rate of left ventricular pressure rise (LV (dP/dt) max). Moreover, SNEC administration distinctly lowered serum levels of ACE and angiotensin II compared to the hypertensive DOCA group. Renal markers, including serum creatinine and BUN, displayed a shift toward normalized levels with SNEC treatment. Additionally, SNEC showcased potent antioxidant characteristics by elevating reduced glutathione, catalase, and superoxide dismutase levels, while decreasing the concentration of thiobarbituric acid reactive substances. Conclusions: Collectively, these findings underscore that curcumin nanoemulsion exerts noteworthy cardio-protective effects through ACE activity inhibition and remarkable antioxidant properties.

Statistical optimization of tetrahydrocurcumin loaded solid lipid nanoparticles using Box Behnken design in the management of streptozotocin-induced diabetes mellitus

In the past, curcumin was the go-to medication for diabetes, but recent studies have shown that tetrahydrocurcumin is more effective. The problem is that it's not very soluble in water or very bioavailable. So, our research aims to increase the bioavailability and anti-diabetic efficacy of tetrahydrocurcumin in streptozotocin-induced diabetic rats by synthesizing tetrahydrocurcumin-loaded solid lipid nanoparticles. Box Behnken Design was employed for the optimization of tetrahydrocurcumin-loaded solid lipid nanoparticles (THC-SLNs). The optimal formulation was determined by doing an ANOVA to examine the relationship between the independent variables (drug-to-lipid ratio, surfactant concentration, and co-surfactant concentration) and the dependent variables (particle size, percent entrapment efficiency, and PDI). Particle size, PDI, and entrapment efficiency all showed statistical significance based on F-values and p-values. The optimized batch was prepared using a drug-to-lipid ratio (1:4.16), 1.21% concentration of surfactant, and 0.4775% co-surfactant (observed with a particle size of 147.1 nm, 83.58 ± 0.838 % entrapment efficiency, and 0.265 PDI, and the values were found very close with the predicted ones. As the THC peak vanishes from the DSC thermogram of the improved formulation, this indicates that the drug has been transformed from its crystalline form into its amorphous state. TEM analysis of optimized formulation demonstrated mono-dispersed particles with an average particle size of 145 nm which are closely related to zetasizer's results. In-vitro release study of optimized formulation demonstrated burst release followed by sustained release up to 71.04% throughout 24 hrs. Increased bioavailability of the adjusted THC-SLN was found in an in vivo pharmacokinetics research with 9.47 folds higher AUC(0-t) compared to plain THC-suspension. Additionally, pharmacodynamic experiments of optimized formulation demonstrated a marked decrease in blood glucose level to 63.7% and increased body weight from 195.8 ± 7.223 to 231.2 ± 7.653 on the 28th day of the study and showed a better anti-diabetic effect than plain drug suspension. Results of stability studies revealed that formulation can be stored for longer periods at room temperature. Tetrahydrocurcumin can be effectively administered by SLN for the treatment of diabetes.

Nanoceria Ameliorates Fibrosis, Inflammation, and Cellular Stress in Experimental Chronic Pancreatitis

Chronic pancreatitis (CP) is an inflammatory, irreversible disorder of the pancreas which leads to organ atrophy and poses high risk for the development of pancreatic cancer. Given the lack of clinically approved therapy, we explored the pharmacological potential of the nanoparticles of cerium oxide (nanoceria, NC) against animal models of CP. Nanoceria ameliorated the features of CP as evident from biochemical parameters. It inhibited the inflammatory cytokines and chemokines by abrogation of macrophage signaling. Further, NC attenuated the fibrogenesis by inhibition of TGF-β signaling, endoplasmic reticulum stress, and epithelial-to-mesenchymal transition. Our findings reveal the anti-CP potential of the novel redox regenerative nanoceria against two models of CP.

NAG-1/GDF15 protects against streptozotocin-induced type 1 diabetes by inhibiting apoptosis, preserving beta-cell function, and suppressing inflammation in pancreatic islets

The loss of functional insulin-producing β-cells is a hallmark of type 1 diabetes mellitus (T1DM). Previously, we reported that the non-steroidal anti-inflammatory drug activated gene-1, or growth differentiation factor-15 (NAG-1/GDF15) inhibits obesity and improves insulin sensitivity in both genetic and dietary-induced obese mice. However, the regulatory role of NAG-1/GDF15 in the structure and function of β-cells and the prevention of T1DM is largely unknown. In the current study, we reported that NAG-1/GDF15 transgenic (Tg) mice are resistant to diabetogenesis induced by multiple low-dose streptozotocin (MLD-STZ) treatment. NAG-1/GDF15 overexpression significantly reduced diabetes incidence, alleviated symptoms of T1DM, and improved MLD-STZ-induced glucose intolerance and insulin resistance. Both the mass and function of pancreatic β cells were preserved in the NAG-1/GDF15 Tg mice as evidenced by significantly increased islet area and insulin production. The mechanistic study revealed that NAG-1/GDF15 significantly inhibited STZ-induced apoptosis and preserved the reduction of proliferation in the islets of the Tg mice as compared to the wild-type (WT) mice upon MLD-STZ treatment. Additionally, NAG-1/GDF15 significantly reduced both the serum and islet levels of the inflammatory cytokines (IL-1β, IL-6, and TNFα), and reduced the expression of NF-κB expression and immune cells infiltration in the islets. Collectively, these results indicate that NAG-1/GDF15 is effective in improving STZ-induced glucose intolerance, probably was mediated via suppressing inflammation, inhibiting apoptosis, and preserving β-cell mass and function.

The levels of nitrite, nitrate and lipid peroxidation in diabetic mouse brain: the effect of melatonin and pentoxifylline

OBJECTIVE

This study investigated the relationship between diabetes (DM) and nitrite, nitrate and MDA levels and effect of melatonin and pentoxifylline.

METHODS

Sixty mice were randomly divided into four groups. Control: no action; Diabetes group (DM): after fasting-blood-glucose (FBG) was measured, 150 mg/kg alloxane was applied intraperitoneally three-times every other day; Diabetes + Melatonin (DM + MLT) and Diabetes + Pentoxifylline groups (DM + PTX): following the same procedures with DM, 10 mg/kg melatonin and 50 mg/kg pentoxifylline were administered subcutaneously six days, respectively. Following FBG analysis, brain tissues were taken under the anaesthesia. Nitrite, nitrate and MDA levels were measured.

RESULTS

In the all groups with alloxane, FBG were higher than in before application (p < .05). Also, FBG, nitrite, nitrate and MDA levels in the DM + MLT and DM + PTX groups were lower than in the DM (p < .05).

CONCLUSIONS

Nitrite and nitrate may be related to etiopathogenesis of DM, and pentoxifylline and especially melatonin relatively decrease nitrite, nitrate and lipid peroxidation.

Co-treatment of Nimbolide augmented the anti-arthritic effects of methotrexate while protecting against organ toxicities

Prolonged exposure to the pharmacological doses of disease-modifying anti-rheumatic drugs (DMARDs) often results in major organ toxicities resulting in poor patient compliance. Methotrexate (MTX) is one of the commonly prescribed DMARDs for the treatment of arthritis, which results in vital organ dysfunction. To retain the anti-arthritic activity of MTX with the reduction in toxicities, combination therapies are warranted. Nimbolide (NMB) is a potent anticancer, anti-inflammatory and anti-fibrotic agent whose potential has been demonstrated in various pre-clinical models. Monoarthritis was developed with Complete Freund's Adjuvant in the knees of Wistar rats and treatment was given with either NMB (3 mg/kg/day) or MTX (2 mg/kg/week) alone or combination therapy (NMB + MTX). The anti-arthritic effects were evaluated by arthritic scoring, radiological imaging, synovial tissue proteins analysis, and histopathological staining. While hepato-renal toxicity was assessed in serum by evaluating the kidney and liver functional parameters, in tissues by oxidative-nitrosative stress markers, and pro-inflammatory cytokines levels. Histopathological analysis was performed to study the extent of tissue damage. Molecular studies like immunoblotting and immunohistochemistry were performed to understand the effect of combination therapy. We thereby report that monotherapy with either NMB or MTX exhibited significant anti-arthritic effects, while combination therapy resulted in augmented anti-arthritic effects with significant reduction in hepato-renal toxicity produced by MTX probably through anti-inflammatory and anti-oxidant effects. Therefore, our proposed combination of NMB and MTX may serve as a potential strategy for the effective management of arthritis.

Pharmacokinetics and Pharmacodynamics of Curcumin-Loaded Solid Lipid Nanoparticles in the Management of Streptozotocin-Induced Diabetes Mellitus: Application of Central Composite Design

Due to poor bioavailability and chemical instability, the effectiveness of curcumin is negligible in the treatment of numerous diseases. Solid lipid nanoparticles (SLNs) increase the bioavailability of lipophilic compounds and protect the drug from gastrointestinal degradation. The objective of our study is the utilization of SLNs to improve the pharmacokinetics and pharmacodynamics of curcumin in the management of diabetes mellitus. Central composite design was used to prepare curcumin-loaded SLNs (Cur-SLN). The analysis of independent variables like drug concentration, lipid concentration, and surfactant concentration was carried out using analysis of variance (ANOVA) to obtain the optimized batch (optimized Cur-SLN) having the desired values of dependent variables particle size and entrapment efficiency. In vitro release, differential scanning calorimeter (DSC), transmission electron microscopy (TEM), and Fourier Transform Infra-Red (FTIR) studies of optimized Cur-SLN were carried out and then its pharmacokinetic and pharmacodynamic studies were performed. The model was found to be significant for particle size and entrapment efficiency based on F-value and p-value. The optimized batch's predicted values were in close agreement with the actual values of particle size and entrapment efficiency. TEM results confirm mono-dispersion and spherical shape of particles in the formulation. The DSC results confirmed the changing of drug from crystalline to amorphous form. Burst release followed by the sustained release was obtained in the in vitro release studies. The pharmacokinetic study shows enhanced bioavailability of optimized Cur-SLN compared with a plain drug suspension. The optimized Cur-SLN achieved higher antidiabetic activity in streptozotocin-induced diabetes mellitus rats than the plain drug suspension. SLNs can be used as a promising technique for delivering curcumin in the management of diabetes mellitus.

Development of a Curcumin-Loaded Polymeric Microparticulate Oral Drug Delivery System for Colon Targeting by Quality-by-Design Approach

The purpose of this study was to apply the quality-by-design (QbD) approach for the development of colon-targeted curcumin-loaded polymeric microparticles (Col-CUR-MPs). The proportion of the enterosoluble polymer (Eudragit^® FS) in the polymeric matrix, curcumin concentration, and the concentration of the polymer mixture (Eudragit^® FS-polycaprolactone) were identified as potential risk factors for the quality of the final product following risk assessment. The influence of these variables on the critical quality attributes (CQAs) of Col-CUR-MPs was investigated. Therefore, a central composite face experimental design was used in order to determine the functional relationships between variables and product CQAs. The obtained regression model and contour plots were used to establish the design space. Finally, the model was validated by preparing two microparticulate formulations, one corresponding to the robust setpoint from within the design space and one outside the established design space, and calculating the percentage bias between the experimental and predicted values. The in vivo study, which was conducted on a fluorescein-loaded formulation that corresponded to the robust setpoint determined by QbD and that contained a mixture of polycaprolactone and Eudragit^® FS (60:40, w/w), confirmed the colon-targeting qualities of this formulation.

Nanocurcumin improved glucose metabolism in streptozotocin-induced diabetic rats: a comparison study with Gliclazide

In the present study, the biochemical effect of nanocurcumin (nanoCUR) compared with Gliclazide (GLZ) on the diabetic rats was studied. Forty male albino rats (Sprague Dawley) weighted 110 ± 20 g were used. Rats were randomly separated into two groups. Control, received no treatment. Streptozotocin (STZ)-induced diabetic groups take 5 ml/kg of STZ in normal saline daily for 30 days, further divided into diabetic non-treated group, did not receive any treatment: diabetic group treated by nanoCUR, received 15 mg/kg/day of nanoCUR orally for 30 days; diabetic group treated by GLZ, received 2 mg/kg/day of GLZ for 30 days. The mean body weights of all rats were registered and serum samples were collected for determination of fasting blood glucose (FBG), insulin concentration, liver glucokinase (GK), and glycogen synthase (GS) activities. Liver tissues were collected for determination of mRNA expression of insulin (INS), insulin receptor A (IRA), glucokinase (GK), and glucose transporter 2 (GLUT2). The results revealed a significant reduction of body weight in diabetic rats, with no significant differences in nanoCUR and GLZ groups. There was a decline in FBG levels and significant elevation of INS levels, GK, and GS activities in diabetic rats received nanoCUR and GLZ. mRNA expression of INS, IRA, GK, and GLUT2 significantly upregulated in diabetic rats received nanoCUR and GLZ. The amazing observation was a non-significant difference in all measured parameters between nanoCUR and GLZ groups. In conclusion, nanoCUR is able to improve cellular uptake of glucose, the hepatic insulin signaling, and insulin sensitivity in diabetic rats. Its effect was similar to standard hypoglycemic drug (GLZ).

Comparative Effect Of Curcumin Versus Liposomal Curcumin On Systemic Pro-Inflammatory Cytokines Profile, MCP-1 And RANTES In Experimental Diabetes Mellitus

Purpose

Anti-inflammatory proprieties of curcumin were proved to be useful in various diseases, including diabetes mellitus. The aim of this study was to assess the anti-inflammatory comparative effect of curcumin solution with liposomal curcumin formula, regarding the improvement of serum levels of TNF-α (tumor necrosis factor-alpha), IL-6 (interleukin), IL-1α, IL-1β, MCP-1 (monocyte chemoattractant protein-1) and RANTES in experimental diabetes, induced by streptozotocin (STZ), in rats.

Materials and methods

Six groups of 7 rats were investigated regarding the effect of i.p. (intraperitoneal) administration of two concentrations of curcumin solution (CC1 and CC2) and two concentrations of liposomal curcumin (LCC1 and LCC2): group 1 – control group with i.p. administration of 1 mL saline solution, group 2 – i.p. STZ administration (60mg/kg bw, bw=body weight), group 3 – STZ+CC1 administration, group 4 – STZ+CC2 administration, group 5 – STZ+ LCC1 administration and group 6 – STZ+ LCC2 administration. The concentrations of curcumin formulas were 1 mg/0.1 kg bw for CC1 and LCC1 and 2 mg/0.1 kg bw for CC2 and LCC2, respectively. Serum levels of C-peptide (as an indicator of pancreatic function) and TNF-α, IL-6, IL-1α, IL-1β, MCP-1, and RANTES (as biomarkers for systemic inflammation) were assessed for each group.

Results

The plasma level of C-peptide showed significant improvements when LCC was administrated, with better results for LCC2 when compared to LCC1 (P<0.003). LCC2 pretreatment proved to be more efficient in reducing the level of TNF-α (P<0.003) and RANTES (P<0.003) than CC2 pretreatment. Upon comparing LCC2 with LCC1 formulas, the differences were significant for TNF-α (P=0.004), IL-1β (P=0.022), and RANTES (P=0.003) levels.

Conclusion

Liposomal curcumin in a dose of 2 mg/0.1 kg bw proved to have an optimum therapeutic effect as a pretreatment in DM induced by STZ. This result can constitute a base for clinical studies for curcumin efficiency as adjuvant therapy in type 1 DM.

Withaferin A reverses bile duct ligation-induced liver fibrosis by modulating extracellular matrix deposition: Role of LOXL2/Snail1, vimentin, and NFκB signaling

Herein, we studied the effect of Withaferin A (WFA) in reversing bile duct ligation (BDL)-induced liver fibrosis. BDL was performed on C57BL/6J mice and 2 days later, WFA (1 and 3 mg/kg) was administered for 12 days. Estimation of liver enzymes and assays for lipid peroxidation, reduced glutathione, and nitrite levels were performed. Picrosirius red, Masson's trichrome, and H&E staining were performed to study histological changes. WFA proved to be a holistic intervention for the attenuation and reversal of liver fibrosis. Reduction in inflammatory stimulus and oxidative stress restored the levels of stress-related chaperone Hsp70 (p < .001 vs. BDL) in WFA treated groups. We found 3.59-fold (p < .001) and 1.37-fold (p < .01) reduction in the expression of lysyl oxidase like2 (LOXL2) and Snail1, respectively, in WFA-treated animals as compared with BDL animals. These reductions led to 1.9-fold (p < .001) elevation in levels of E-cadherin signifying the reversal of epithelial to mesenchymal transition by WFA. Further, the reduction in LOXL2 levels enhanced the susceptibility of fibrotic scar toward degradation. The picrosirius red and Masson's trichrome staining done on liver tissue sections supported the above results. We, for the first time, report the role of WFA in modulating the expression of LOXL2 and Snail1 in addition to vimentin inhibition and regulation of NFκB signaling for the treatment of liver fibrosis.