Poloxamer 407/188 Binary Thermosensitive Gel as a Moxidectin Delivery System: In Vitro Release and In Vivo Evaluation

Moxidectin (MXD) is an antiparasitic drug used extensively in veterinary clinics. In this study, to develop a new formulation of MXD, a thermosensitive gel of MXD (MXD-TG) was prepared based on poloxamer 407/188. Furthermore, the gelation temperature, the stability, in vitro release kinetics and in vivo pharmacokinetics of MXD-TG were evaluated. The results showed that the gelation temperature was approximately 27 °C. MXD-TG was physically stable and can be released continuously for more than 96 h in vitro. The Korsmeyer–Peppas model provided the best fit to the release kinetics, and the release mechanism followed a diffusive erosion style. MXD-TG was released persistently for over 70 days in sheep. Part of pharmacokinetic parameters had a difference in female and male sheep (p < 0.05). It was concluded that MXD-TG had a good stability, and its release followed the characteristics of a diffusive erosion style in vitro and a sustained release pattern in vivo.     

Self-Nanoemulsifying Drug Delivery System (SNEDDS) of Apremilast: In Vitro Evaluation and Pharmacokinetics Studies

Psoriatic arthritis is an autoimmune disease of the joints that can lead to persistent inflammation, irreversible joint damage and disability. The current treatments are of limited efficacy and inconvenient. Apremilast (APR) immediate release tablets Otezla^® have 20–33% bioavailability compared to the APR absolute bioavailability of 73%. As a result, self-nanoemulsifying drug delivery systems (SNEDDS) of APR were formulated to enhance APR’s solubility, dissolution, and oral bioavailability. The drug assay was carried out using a developed and validated HPLC method. Various thermodynamic tests were carried out on APR-SNEDDS. Stable SNEDDS were characterized then subjected to in vitro drug release studies via dialysis membrane. The optimum formulation was F9, which showed the maximum in vitro drug release (94.9%) over 24 h, and this was further investigated in in vivo studies. F9 was composed of 15% oil, 60% S_mix, and 25% water and had the lowest droplet size (17.505 ± 0.247 nm), low PDI (0.147 ± 0.014), low ZP (−13.35 mV), highest %T (99.15 ± 0.131) and optimum increases in the relative bioavailability (703.66%) compared to APR suspension (100%) over 24 h. These findings showed that APR-SNEDDS is a possible alternative delivery system for APR. Further studies are warranted to evaluate the major factors that influence the encapsulation efficiency and stability of APR-containing SNEDDS.     

In Vitro–In Vivo Correlation of Tianeptine Sodium Sustained-Release Dual-Layer Tablets

Tianeptine tablets are currently marketed to be designed for immediate-release tablets. The tianeptine has a short half-life, making it difficult to design for sustained-release tablets and achieve bioequivalence with the tianeptine immediate-release tablet (Stablon^®). We established the in vitro–in vivo correlation (IVIVC) of three formulations of tianeptine sustained-release tablets according to their granule size. To evaluate sustained drug release, in vitro tests were performed in pH 1.2 media for 24 h. In vivo pharmacokinetic analysis was performed following oral administration of reference drug and test drug to beagle dogs. The dissolution profile revealed delayed release as the size of the granules increased. The dissolution results were confirmed in pharmacokinetic analysis, showing that the half-life was delayed as granule size increased. The final formulation and reference drug showed an equivalent area under the curve (AUC). Through this, IVIVC was established according to the size of the tianeptine sodium granules, which is the purpose of this study, and was used to predict in vivo pharmacokinetics from the formulation composition. This approach may be useful for determining optimal formulation compositions to achieve the desired pharmacokinetics when developing new formulations.     

In Vitro Antineoplastic and Antiviral Activity and In Vivo Toxicity of Geum urbanum L. Extracts

This study evaluated the in vitro antineoplastic and antiviral potential and in vivo toxicity of twelve extracts with different polarity obtained from the herbaceous perennial plant Geum urbanum L. (Rosaceae). In vitro cytotoxicity was determined by ISO 10993-5/2009 on bladder cancer, (T-24 and BC-3C), liver carcinoma (HEP-G2) and normal embryonic kidney (HEK-293) cell lines. The antineoplastic activity was elucidated through assays of cell clonogenicity, apoptosis induction, nuclear factor kappa B p65 (NFκB p65) activation and total glutathione levels. Neutral red uptake study was applied for antiviral activity. The most promising G. urbanum extract was analyzed by UHPLC–HRMS. The acute in vivo toxicity analysis was carried out following OEDC 423. The ethyl acetate extract of aerial parts (EtOAc-AP) exhibited the strongest antineoplastic activity on bladder cancer cell lines (IC₅₀ = 21.33–25.28 µg/mL) by inducing apoptosis and inhibiting NFκB p65 and cell clonogenicity. EtOAc and n-butanol extracts showed moderate antiviral activity against human adenovirus type 5 and human simplex virus type I. Seventy four secondary metabolites (gallic and ellagic acid derivatives, phenolic acids, flavonoids, etc.) were identified in EtOAc-AP by UHPLC–HRMS. This extract induced no signs of acute toxicity in liver and kidney specimens of H-albino mice in doses up to 210 mg/kg. In conclusion, our study contributes substantially to the detailed pharmacological characterization of G. urbanum, thus helping the development of health-promoting phytopreparations.     

Pimenta dioica (L.) Merr. Bioactive Constituents Exert Anti-SARS-CoV-2 and Anti-Inflammatory Activities: Molecular Docking and Dynamics,In Vitro,and In Vivo Studies

In response to the urgent need to control Coronavirus disease 19 (COVID-19), this study aims to explore potential anti-SARS-CoV-2 agents from natural sources. Moreover, cytokine immunological responses to the viral infection could lead to acute respiratory distress which is considered a critical and life-threatening complication associated with the infection. Therefore, the anti-viral and anti-inflammatory agents can be key to the management of patients with COVID-19. Four bioactive compounds, namely ferulic acid 1, rutin 2, gallic acid 3, and chlorogenic acid 4 were isolated from the leaves of Pimenta dioica (L.) Merr (ethyl acetate extract) and identified using spectroscopic evidence. Furthermore, molecular docking and dynamics simulations were performed for the isolated and identified compounds (1–4) against SARS-CoV-2 main protease (Mpro) as a proposed mechanism of action. Furthermore, all compounds were tested for their half-maximal cytotoxicity (CC₅₀) and SARS-CoV-2 inhibitory concentrations (IC₅₀). Additionally, lung toxicity was induced in rats by mercuric chloride and the effects of treatment with P. dioca aqueous extract, ferulic acid 1, rutin 2, gallic acid 3, and chlorogenic acid 4 were recorded through measuring TNF-α, IL-1β, IL-2, IL-10, G-CSF, and genetic expression of miRNA 21-3P and miRNA-155 levels to assess their anti-inflammatory effects essential for COVID-19 patients. Interestingly, rutin 2, gallic acid 3, and chlorogenic acid 4 showed remarkable anti-SARS-CoV-2 activities with IC₅₀ values of 31 µg/mL, 108 μg/mL, and 360 µg/mL, respectively. Moreover, the anti-inflammatory effects were found to be better in ferulic acid 1 and rutin 2 treatments. Our results could be promising for more advanced preclinical and clinical studies especially on rutin 2 either alone or in combination with other isolates for COVID-19 management.     

Formulation and Optimization of Alogliptin-Loaded Polymeric Nanoparticles: In Vitro to In Vivo Assessment

The nano-drug delivery system has gained greater acceptability for poorly soluble drugs. Alogliptin (ALG) is a FDA-approved oral anti-hyperglycemic drug that inhibits dipeptidyl peptidase-4. The present study is designed to prepare polymeric ALG nanoparticles (NPs) for the management of diabetes. ALG-NPs were prepared using the nanoprecipitation method and further optimized by Box–Behnken experimental design (BBD). The formulation was optimized by varying the independent variables Eudragit RSPO (A), Tween 20 (B), and sonication time (C), and the effects on the hydrodynamic diameter (Y1) and entrapment efficiency (Y2) were evaluated. The optimized ALG-NPs were further evaluated for in vitro release, intestinal permeation, and pharmacokinetic and anti-diabetic activity. The prepared ALG-NPs show a hydrodynamic diameter of between 272.34 nm and 482.87 nm, and an entrapment efficiency of between 64.43 and 95.21%. The in vitro release data of ALG-NPs reveals a prolonged release pattern (84.52 ± 4.1%) in 24 h. The permeation study results show a 2.35-fold higher permeation flux than pure ALG. ALG-NPs exhibit a significantly (p < 0.05) higher pharmacokinetic profile than pure ALG. They also significantly (p < 0.05) reduce the blood sugar levels as compared to pure ALG. The findings of the study support the application of ALG-entrapped Eudragit RSPO nanoparticles as an alternative carrier for the improvement of therapeutic activity.     

Therapeutic Potential of Tuna Backbone Peptide and Its Analogs: An In Vitro and In Silico Study

Tuna backbone peptide (TBP) has been reported to exert potent inhibitory activity against lipid peroxidation in vitro. Since this bears relevant physiological implications, this study was undertaken to assess the impact of peptide modifications on its bioactivity and other therapeutic potential using in vitro and in silico approach. Some TBP analogs, despite lower purity than the parent peptide, exerted promising antioxidant activities in vitro demonstrated by ABTS radical scavenging assay and cellular antioxidant activity assay. In silico digestion of the peptides resulted in the generation of antioxidant, angiotensin-converting enzyme (ACE), and dipeptidyl peptidase-IV (DPPIV) inhibitory dipeptides. Using bioinformatics platforms, we found five stable TBP analogs that hold therapeutic potential with their predicted multifunctionality, stability, non-toxicity, and low bitterness intensity. This work shows how screening and prospecting for bioactive peptides can be improved with the use of in vitro and in silico approaches.     

In Vitro and In Vivo Evaluation of Tetracycline Loaded Chitosan‐Gelatin Nanosphere Coatings for Titanium Surface Functionalization

Owing to the biocompatibility of titanium surface, titanium implants are suitable substrates for microbial colonization and biofilm formation, which is still a serious clinical threat. Current research trends have been focused on the development of antibacterial coatings on titanium substrate or adhesion resistant surface. In our previous study, tetracycline (Tc) loaded chitosan‐gelatin (CSG) nanosphere coatings are successfully fabricated on titanium substrates via electrophoretic deposition. These coatings show nanosphere structure, and excellent antibacterial property in vitro. However, further in vitro and in vivo evaluation of the coatings is required for the future application. Therefore, in the present study, the authors investigate the coatings' mechanical, swelling and degradation property, in vitro cellular response to preosteoblast cells, and the antibacterial property in rabbits. Results show that Tc incorporation can improve the tensile bond strength of the coating, decrease the swelling ratio, and accelerate the degradation of the coating. Although high Tc concentration group exhibits cytotoxicity to MC3T3‐E1 cells, its in vivo antibacterial property is preferred, and shows better outcome than the prophylactic administration of Tc. Tc loaded CSG nanosphere coatings are suitable antibacterial coatings for titanium surface functionalization.

     

In Vitro and In Vivo Antidiabetic Potential of Monoterpenoids: An Update

Diabetes mellitus (DM) is a chronic metabolic condition characterized by persistent hyperglycemia due to insufficient insulin levels or insulin resistance. Despite the availability of several oral and injectable hypoglycemic agents, their use is associated with a wide range of side effects. Monoterpenes are compounds extracted from different plants including herbs, vegetables, and fruits and they contribute to their aroma and flavor. Based on their chemical structure, monoterpenes are classified into acyclic, monocyclic, and bicyclic monoterpenes. They have been found to exhibit numerous biological and medicinal effects such as antipruritic, antioxidant, anti-inflammatory, and analgesic activities. Therefore, monoterpenes emerged as promising molecules that can be used therapeutically to treat a vast range of diseases. Additionally, monoterpenes were found to modulate enzymes and proteins that contribute to insulin resistance and other pathological events caused by DM. In this review, we highlight the different mechanisms by which monoterpenes can be used in the pharmacological intervention of DM via the alteration of certain enzymes, proteins, and pathways involved in the pathophysiology of DM. Based on the fact that monoterpenes have multiple mechanisms of action on different targets in in vitro and in vivo studies, they can be considered as lead compounds for developing effective hypoglycemic agents. Incorporating these compounds in clinical trials is needed to investigate their actions in diabetic patients in order to confirm their ability in controlling hyperglycemia.     

Anthracene-Derived Bis-Aminophosphonates: Crystal Structure,In Vitro Antitumor Activity,and Genotoxicity In Vivo

Abstract

The X-ray crystal structures of the anthracene-derived bis-aminophosphonates 4.4′-bis[N-methyl(diethoxyphosphonyl)-1-(9-anthryl)]diaminodiphenylmethane (1) and 1,3-bis

[N-methyl(diethoxyphosphonyl)-1-(9-anthryl)]diaminobenzene (3) are reported. The X-ray analyses demonstrated that both compounds crystallize in a centrosymmetric manner containing a meso-form (1) and a pair of enantiomers (3).

The cytotoxic potential, genotoxicity, and antiproliferative activity of bis-aminophosphonates 1 and bis[N-methyl(diethoxyphosphonyl)-1-(9-anthryl)]benzidine (2), as well as their subcellular distribution in a tumor cell culture system, are also discussed. Compounds 1 and 2 showed optimal antiproliferative activity to human tumor cells from colon carcinoma line HT-29. In vitro and in vivo safety testing revealed that the compounds exert lower toxicity to normal cells as compared with well-known anticancer and cytotoxic agents.

Supplemental materials are available for this article. Go to the publisher's online edition ofPhosphorus, Sulfur, and Silicon and the Related Elementsto view the free supplemental file.     

The Therapeutic Potential of Celastrol in Central Nervous System Disorders: Highlights from In Vitro and In Vivo Approaches

Celastrol, the most abundant compound derived from the root of Tripterygium wilfordii, largely used in traditional Chinese medicine, has shown preclinical and clinical efficacy for a broad range of disorders, acting via numerous mechanisms, including the induction of the expression of several neuroprotective factors, the inhibition of cellular apoptosis, and the decrease of reactive oxygen species (ROS). Given the crucial implication of these pathways in the pathogenesis of Central Nervous System disorders, both in vitro and in vivo studies have focused their attention on the possible use of this compound in these diseases. However, although most of the available studies have reported significant neuroprotective effects of celastrol in cellular and animal models of these pathological conditions, some of these data could not be replicated. This review aims to discuss current in vitro and in vivo lines of evidence on the therapeutic potential of celastrol in neurodegenerative diseases, including Alzheimer’s and Parkinson’s diseases, amyotrophic lateral sclerosis, Huntington’s disease, multiple sclerosis, and cadmium-induced neurodegeneration, as well as in psychiatric disorders, such as psychosis and depression. In vitro and in vivo studies focused on celastrol effects in cerebral ischemia, ischemic stroke, traumatic brain injury, and epilepsy are also described.     

Evaluation of 2-Thioxoimadazolidin-4-one Derivatives as Potent Anti-Cancer Agents through Apoptosis Induction and Antioxidant Activation: In Vitro and In Vivo Approaches

Background: Hepatocellular carcinoma (HCC) is one of the most widespread malignancies and is reported as the fourth most prevalent cause of cancer deaths worldwide. Therefore, we aimed to investigate the probable mechanistic cytotoxic effect of the promising 2-thioxoimidazolidin-4-one derivative on liver cancer cells using in vitro and in vivo approaches. The compounds were tested for the in vitro cytotoxic activity using MTT assay, and the promising compound was tested in colony forming unit assay, flow cytometric analysis, RT-PCR, Western blotting, in vivo using SEC-carcinoma and in silico to highlight the virtual mechanism of action. Both compounds 4 and 2 performed cytotoxic effects against HepG2 cells with IC₅₀ values of 0.017 and 0.18 μM, respectively, compared to Staurosporine and 5-Fu as reference drugs with IC₅₀ values of 5.07 and 5.18 µM, respectively. Compound 4 treatment revealed apoptosis induction by 19.35-fold (11.42% compared to 0.59% in control), arresting the cell cycle at G2/M phase. Moreover, studying gene expression that plays critical roles in cell cycle and apoptosis by RT-PCR demonstrated that compound 4 enhances the expression of the pro-apoptotic genes p53, PUMA, and Caspase 3, 8, and 9, and impedes the anti-apoptotic Bcl-2 gene in the HepG2 cells. It can also inhibit the PI3K/AKT pathway at both gene and protein levels, which was reinforced by the in silico predictions of the molecular docking simulations towards the PI3K/AKT proteins. Finally, in vivo study verified that compound 4 has a promising anti-cancer activity through activating antioxidant levels (CAT, SOD and GSH) and ameliorating hematological, biochemical, and histopathological findings.     

Carduus edelbergii Rech. f. Mediated Fabrication of Gold Nanoparticles; Characterization and Evaluation of Antimicrobial,Antioxidant and Antidiabetic Potency of the Synthesized AuNPs

Background: Due to the high expense, less effectiveness and more side effects of available synthetic medicine, the researchers and communities are focusing on phyto-based natural bioactive compounds, which are considered safer for the treatment of syndromes and chronic diseases. Aim: The current project was aimed to determine the phytochemicals constituents available in the aerial parts of methanol extract of Carduus edelbergii via GC-MS, fabrication of AuNPs mediated with the mentioned extract; characterization and evaluation of antimicrobial, antioxidant and antidiabetic potency of the synthesized AuNPs. Methods: Confirmation of green synthesis of AuNPs, functional groups responsible for the reduction in Au⁺, size and crystallinity, morphology and quantity of gold (Au) were carried out by Ultraviolet-Visible (UV-Vis) spectroscopy, Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and dispersive X-ray (EDX), respectively, whereas in vitro antioxidant characteristics were assessed by DPPH and ABTS assays. Wistar albino rats were used to test the anti-diabetic properties of the methanol extract and AuNPs. Results: GC-MS revealed that the diluted methanol extract of Carduus edelbergii consists of about 19 chemical constituents. Among the identified compounds, the 13-Docosenoic acid, methyl ester, (Z)—has the highest concentration (38.16%), followed by 9-Octadecenoic acid, methyl ester, (E)—(15.72%) and n-Hexadecanoic acid (15.07%). Methanol extract and its fabricated nanoparticles showed significant antioxidant and antimicrobial activities. In vivo antidiabetic study revealed a noteworthy (p < 0.05) decline in body weight and HDL and elevated concentration of blood glucose, bilirubin, creatinine, urea, triglyceride, VLDL, LDL, ALP, ALT and AST in diabetic control. The said changes were recovered significantly (p < 0.05) by treatment of diabetic rats with methanol extract (150 and 300 mg/Kg BW) and AuNPs of Carduus edelbergii (5 and 10 mg/Kg BW). Conclusion: The green synthesized AuNPs exhibit significant antioxidant, antimicrobial and antidiabetic characteristics.     

Glucose Biosensor Based on Oxygen Electrode Part IV: In Vivo Evaluation of the Rechargeable Glucose Sensor

Abstract

A glucose monitoring system consisting of a pair of amperometric sensors: a glucose biosensor based on oxygen electrode and an oxygen sensor, two miniature potentiostats, an instrumentation amplifier and a data logger has been developed. The glucose sensor has linear response to the glucose concentration in vitro at 37°C up to 26 mM (480 mg/dL) in the phosphate buffer solution (pH 7.4), and linear range up to 21 mM (380 mg/dL) in undiluted bovine plasma. The system was evaluated in vivo with the sensors subcutaneously implanted in healthy mongrel dogs. During the implantation the system output was continuously recorded. The results of short-term subcutaneous implantation of the integrated system demonstrated good agreement between the glucose concentration measured by the biosensor and that obtained using standard glucose determination methods. The delay-time between the tissue glucose level (measured by the biosensor) and the blood glucose level (obtained by standard methodology) was 3 to 10 minutes. During the chronic implantation the biosensor was refilled in vivo. Rejuvenation of the sensor response after refilling was observed demonstrating the potential of such sensors for long-term implantation.     

Multifunctional Derivatives of Spiropyrrolidine Tethered Indeno-Quinoxaline Heterocyclic Hybrids as Potent Antimicrobial,Antioxidant and Antidiabetic Agents: Design,Synthesis, In Vitro and In Silico Approaches

To combat emerging antimicrobial-resistant microbes, there is an urgent need to develop new antimicrobials with better therapeutic profiles. For this, a series of 13 new spiropyrrolidine derivatives were designed, synthesized, characterized and evaluated for their in vitro antimicrobial, antioxidant and antidiabetic potential. Antimicrobial results revealed that the designed compounds displayed good activity against clinical isolated strains, with 5d being the most potent (MIC 3.95 mM against Staphylococcus aureus ATCC 25923) compared to tetracycline (MIC 576.01 mM). The antioxidant activity was assessed by trapping DPPH, ABTS and FRAP assays. The results suggest remarkable antioxidant potential of all synthesized compounds, particularly 5c, exhibiting the strongest activity with IC₅₀ of 3.26 ± 0.32 mM (DPPH), 7.03 ± 0.07 mM (ABTS) and 3.69 ± 0.72 mM (FRAP). Tested for their α-amylase inhibitory effect, the examined analogues display a variable degree of α-amylase activity with IC₅₀ ranging between 0.55 ± 0.38 mM and 2.19 ± 0.23 mM compared to acarbose (IC₅₀ 1.19 ± 0.02 mM), with the most active compounds being 5d, followed by 5c and 5j, affording IC₅₀ of 0.55 ± 0.38 mM, 0.92 ± 0.10 mM, and 0.95 ± 0.14 mM, respectively. Preliminary structure–activity relationships revealed the importance of such substituents in enhancing the activity. Furthermore, the ADME screening test was applied to optimize the physicochemical properties and determine their drug-like characteristics. Binding interactions and stability between ligands and active residues of the investigated enzymes were confirmed through molecular docking and dynamic simulation study. These findings provided guidance for further developing leading new spiropyrrolidine scaffolds with improved dual antimicrobial and antidiabetic activities.     

In Vitro and In Vivo Enzyme‐Mediated Biomineralization of Oligo(poly(ethylene glycol) Fumarate Hydrogels

The enzyme alkaline phosphatase (ALP) is added at different concentrations (i.e., 0, 2.5, and 10 mg · ml^?1) to oligo(poly(ethylene glycol)fumarate) (OPF) hydrogels. The scaffolds are either incubated in 10 mM calcium glycerophosphate (Ca–GP) solution for 2 weeks or implanted in a rat subcutaneous model for 4 weeks. Fourier transform infrared (FTIR) spectroscopy, X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and alizarin red staining show a strong ability to form minerals exclusively in ALP‐containing hydrogels in vitro. Additionally, the calcium content increases with increasing ALP concentration. Similarly, only ALP‐containing hydrogels induce mineralization in vivo. Specifically, small (≈5–20 µm) mineral deposits are observed at the periphery of the hydrogels near the dermis/scaffold interface using Von Kossa and alizarin red staining.

     

Preclinical Pharmacokinetics and Bioavailability of Oxypeucedanin in Rats after Single Intravenous and Oral Administration

Oxypeucedanin, a furanocoumarin extracted from many traditional Chinese herbal medicines, has a variety of pharmacological effects. However, the independent pharmacokinetic characteristics and bioavailability of this compound remains elusive. In this study, a rapid, sensitive, and selective method using ultra-high performance liquid chromatography–tandem mass spectrometry (UPLC/MS/MS) was developed for evaluating the intravenous and oral pharmacokinetics of oxypeucedanin. After intravenous administration of oxypeucedanin (2.5, 5, and 10 mg/kg), and intragastric administration of oxypeucedanin (20 mg/kg), blood samples were collected periodically from the tail vein. The plasma concentration-time curves were plotted, and the pharmacokinetic parameters were calculated using a non-compartmental model analysis. After intravenous administration of oxypeucedanin (single dosing at 2.5, 5, and 10 mg/kg) to rats, the pharmacokinetics fit the linear kinetics characteristics, which showed that some parameters including average elimination half-life (T_1/2Z of 0.61~0.66 h), mean residence time (MRT of 0.62~0.80 h), apparent volume of distribution (V_Z of 4.98~7.50 L/kg), and systemic clearance (CL_Z of 5.64~8.55 L/kg/h) are dose-independent and the area under concentration-time curve (AUC) increased in a dose-proportional manner. Single oral administration of oxypeucedanin (20 mg/kg) showed poor and slow absorption with the mean time to reach the peak concentration (T_max) of 3.38 h, MRT of 5.86 h, T_1/2Z of 2.94 h, and a mean absolute bioavailability of 10.26% in rats. These results provide critical information for a better understanding of the pharmacological effect of oxypeucedanin, which will facilitate its research and development.     

Brazilian Red Propolis Presents Promising Anti-H. pylori Activity in In Vitro and In Vivo Assays with the Ability to Modulate the Immune Response

Helicobacter pylori is a Gram-negative, microaerophilic, curved-rod, flagellated bacterium commonly found in the stomach mucosa and associated with different gastrointestinal diseases. With high levels of prevalence worldwide, it has developed resistance to the antibiotics used in its therapy. Brazilian red propolis has been studied due to its biological properties, and in the literature, it has shown promising antibacterial activities. The aim of this study was to evaluate anti-H. pylori from the crude hydroalcoholic extract of Brazilian red propolis (CHEBRP). For this, in vitro determination of the minimum inhibitory and bactericidal concentration (MIC/MBC) and synergistic activity and in vivo, microbiological, and histopathological analyses using Wistar rats were carried out using CHEBRP against H. pylori strains (ATCC 46523 and clinical isolate). CHEBRP presented MIC/MBC of 50 and 100 μg/mL against H. pylori strains (ATCC 43526 and clinical isolate, respectively) and tetracycline MIC/MBC of 0.74 µg/mL. The association of CHEBRP with tetracycline had an indifferent effect. In the stomach mucosa of rats, all treatments performed significantly decreased the number of H. pylori, and a concentration of 300 mg/kg was able to modulate the inflammatory response in the tissue. Therefore, CHEBRP showed promising anti-H. pylori in in vitro and in vivo assays.     

Design and Evaluation of a Lactate Microbiosensor: Toward Multianalyte Monitoring of Neurometabolic Markers In Vivo in the Brain

Direct in vivo measurements of neurometabolic markers in the brain with high spatio-temporal resolution, sensitivity, and selectivity is highly important to understand neurometabolism. Electrochemical biosensors based on microelectrodes are very attractive analytical tools for continuous monitoring of neurometabolic markers, such as lactate and glucose in the brain extracellular space at resting and following neuronal activation. Here, we assess the merits of a platinized carbon fiber microelectrode (CFM/Pt) as a sensing platform for developing enzyme oxidase-based microbiosensors to measure extracellular lactate in the brain. Lactate oxidase was immobilized on the CFM/Pt surface by crosslinking with glutaraldehyde. The CFM/Pt-based lactate microbiosensor exhibited high sensitivity and selectivity, good operational stability, and low dependence on oxygen, temperature, and pH. An array consisting of a glucose and lactate microbiosensors, including a null sensor, was used for concurrent measurement of both neurometabolic substrates in vivo in the anesthetized rat brain. Rapid changes of lactate and glucose were observed in the cortex and hippocampus in response to local glucose and lactate application and upon insulin-induced fluctuations of systemic glucose. Overall, these results indicate that microbiosensors are a valuable tool to investigate neurometabolism and to better understand the role of major neurometabolic markers, such as lactate and glucose.     

Bruguiera gymnorhiza (L.) Lam. at the Forefront of Pharma to Confront Zika Virus and Microbial Infections—An In Vitro and In Silico Perspective

The recent emergence of Zika virus (ZIKV) in Brazil and the increasing resistance developed by pathogenic bacteria to nearly all existing antibiotics should be taken as a wakeup call for the international authority as this represents a risk for global public health. The lack of antiviral drugs and effective antibiotics on the market triggers the need to search for safe therapeutics from medicinal plants to fight viral and microbial infections. In the present study, we investigated whether a mangrove plant, Bruguiera gymnorhiza (L.) Lam. (B. gymnorhiza) collected in Mauritius, possesses antimicrobial and antibiotic potentiating abilities and exerts anti-ZIKV activity at non-cytotoxic doses. Microorganisms Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 70603, methicillin-resistant Staphylococcus aureus ATCC 43300 (MRSA), Salmonella enteritidis ATCC 13076, Sarcina lutea ATCC 9341, Proteus mirabilis ATCC 25933, Bacillus cereus ATCC 11778 and Candida albicans ATCC 26555 were used to evaluate the antimicrobial properties. Ciprofloxacin, chloramphenicol and streptomycin antibiotics were used for assessing antibiotic potentiating activity. ZIKV^MC-MR766NIID (ZIKV^GFP) was used for assessing anti-ZIKV activity. In silico docking (Autodock 4) and ADME (SwissADME) analyses were performed on collected data. Antimicrobial results revealed that Bruguiera twig ethyl acetate (BTE) was the most potent extract inhibiting the growth of all nine microbes tested, with minimum inhibitory concentrations ranging from 0.19–0.39 mg/mL. BTE showed partial synergy effects against MRSA and Pseudomonas aeruginosa when applied in combination with streptomycin and ciprofloxacin, respectively. By using a recombinant ZIKV-expressing reporter GFP protein, we identified both Bruguiera root aqueous and Bruguiera fruit aqueous extracts as potent inhibitors of ZIKV infection in human epithelial A549 cells. The mechanisms by which such extracts prevented ZIKV infection are linked to the inability of the virus to bind to the host cell surface. In silico docking showed that ZIKV E protein, which is involved in cell receptor binding, could be a target for cryptochlorogenic acid, a chemical compound identified in B. gymnorhiza. From ADME results, cryptochlorogenic acid is predicted to be not orally bioavailable because it is too polar. Scientific data collected in this present work can open a new avenue for the development of potential inhibitors from B. gymnorhiza to fight ZIKV and microbial infections in the future.