Marsela Garza-Tapia

Liver disease represents a major global health issue, with limited availability of effective hepatoprotective treatments. Hojasé or hojasén or Flourensia cernua (Fc) is known for its antioxidant properties and high phenolic content and may exhibit a potential hepatoprotective effect. Additionally, natural products have been shown to restore gut microbiota and reduce liver inflammation. To evaluate the hepatoprotective activity of Fc and its impact on gut microbiota in a valproic acid (VPA)-induced injury model in Wistar rats. Seven groups of Wistar rats (n = 6) were treated as follows: Sham; Non-toxic Fc (NTox 200 and 400 mg/kg); VPA 500 mg/kg; VPA + Fc 200 and VPA + Fc 400; and silybinin 500 mg/kg (VPA + Slb). Liver function tests, malondialdehyde (MDA) and superoxide dismutase (SOD) markers, aerobic gut microbiota analysis, and histological analysis were conducted. No significant differences were observed in ALT and AST levels between NTox 200, NTox 400, and Sham. Only the 400 mg/kg dose of Fc significantly reduced ALT and AST versus VPA, similar to Slb. In VPA + Fc 200 and VPA + Fc 400, MDA and SOD decreased versus VPA, comparable to VPA + Slb. Only VPA + Fc 400 and VPA + Slb restored aerobic gut microbiota versus VPA. No histological changes were observed between groups. Fc extract demonstrated hepatoprotective effects at a dose of 400 mg/kg and impacted the restoration of aerobic gut microbiota against VPA-induced damage.

Background: The presence of side effects and low bioavailability of rhein has limited its use in the treatment of osteoarthritis. We aimed to evaluate the in vitro response of human articular chondrocytes to the presence of the combination of platelet-rich plasma (PRP) and rhein. Methods: Solutions of rhein were prepared to assess solubility and select a working concentration. A stimulus with interleukin-1β (IL-β, 10 ng/mL) was induced for 24 h on human chondrocytes. Five treatment groups were established: control, IL-β control, PRP, rhein, and PRP + rhein. Cell viability, cell migration, nitric oxide (NO) production, tumor necrosis factor-α (TNF-α), and gene expression analyses were carried out. Results: A concentration of 50 mg/L was selected after a dose–response curve assay. Both NO and tumor TNF-α production significantly decreased after PRP and PRP + rhein treatments at 24 and 48 h. The wound healing assay revealed a significant stimulation of migration after 72 h with the PRP and PRP + rhein treatments. Expression of IL-1β, IL-6, MMP-13, and ADAMTS-5 was significantly downregulated, particularly after treatment with the combination of PRP + rhein. Conclusions: Much of the determinations denoted a better performance of the combination of PRP and rhein in decreasing the levels of the different targets evaluated; however, this was not great enough to detect a significant difference in comparison with the PRP treatment alone.

Eudragit^® polymers have proven their potential as a means to control the release of aqueous insoluble drugs in various delivery systems as polymer nanoparticles (PNPs). The size (S) and polydispersity index (PDI) of PNPs are crucial factors for their interaction with biological systems from a pharmaceutical standpoint. This study aimed to determine the impact of the volumes of the organic phase (OP) and aqueous phase (AP), as well as the polymer amount (PA), on the size and PDI of PNPs prepared using the nanoprecipitation method for encapsulating quercetin (Qr). The study also evaluated the toxic effects of PNPs on human erythrocytes. The PNPs were prepared using preformed polymers derived from methacrylic acid and polyvinyl alcohol (PVA) as a surfactant. The nanoprecipitation technique enabled the production of particles smaller than 200 nm with a PDI lower than 0.2, and the study established the significant impact (p < 0.05) of the three variables related to the polymers and solvents. The selected PNPs contained 5 mg of Qr and 50 mg of Eudragit polymers (1:10 w/w Eudragit^® EPO, E100, L100, and Eudragit L100-55) and diverse concentrations of PVA. The study found that including PVA in the AP increased the Qr encapsulation by up to 98%. The hemolytic potential of Eudragit^® PNPs and Qr was assessed in human erythrocytes, with no significant cytotoxic activity observed (p < 0.001) compared with the control. In conclusion, via the nanoprecipitation technique, preparing PNPs with defined and homogeneous S to entrap the flavonol Qr efficiently is possible.

The usefulness of traditional plants in Mexico to treat human ailments has been known since ancient times. This work evaluated the antimicrobial, anticoagulant, antioxidant, cytotoxic, and anti-inflammatory potential of ethanolic extracts of Aloe vera, Equisetum arvense, Mimosa tenuiflora, Lippia graveolens, and Syzygium aromaticum. The antimicrobial activity of the extracts was evaluated against Streptococcus mutans and Streptococcus sorbinus; a significant inhibitory effect of the L. graveolens extract on both bacteria was observed at concentration levels of 250 µg/mL and greater. The anticoagulant activity was evaluated in terms of prothrombin time (PT) and activated partial thromboplastin time (APTT), A. vera and M. tenuiflora extracts showed no significant difference (p ˂ 0.05) in PT compared with the control, and for APTT the extracts of A. vera, L. graveolens, and S. aromaticum decreased the APTT significantly (p ˂ 0.05) compared with the control. The antioxidant potential by DPPH assay indicated that the E. arvense extract behaved statistically the same as the control. The cytotoxic activity was evaluated in HGF-1 cells using the fluorometric microculture cytotoxicity assay technique, and none of the extracts was toxic at 125 and 250 µg/mL concentrations. Finally, the anti-inflammatory activity was evaluated using ELISA, where the A. vera extract showed the best anti-inflammatory capacity. Further research on the search for bioactive metabolites and elucidation of action mechanisms of the most promising extracts will be carried out.

A novel coating for solid-phase microextraction (SPME) fibers was manufactured by using a mixture of 1-decyl-3methylimidazolium tetrafluoroborate ionic liquid and a commercial adhesive deposited on an etched stainless-steel support. The new coating was characterized by applying optical and electron microscopy, infrared spectroscopy and its extraction capacity was also evaluated. The extraction capacity was tested using as model analytes some pharmaceutical and personal care products (PPCPs) with different hydrophilicities. The potential use of the new fiber was evaluated through direct-immersion mode extractions and showed extraction capacity toward methylparaben, propylparaben, naproxen, diclofenac and benzophenone-3. Experimental design tools were used to study and optimize the variables that affect the extraction and desorption processes of the SPME by direct immersion. The analytical performance of proposed method was investigated under SPME procedure´s optimal conditions, coupled to a high-performance liquid chromatography-diode array detector (HPLC-DAD) method, which was developed and validated for analysis of the target PPCPs. The method of SPME by direct immersion was linear, precise and accurate. Detection and quantification limits of 0.023 to 0.093 μg mL-1 and 0.118 to 0.279 μg mL-1 were obtained, respectively. By the use of the developed method, tap water samples were analyzed and recoveries from 3.39 to 183.29 % were found. The new fiber presented an adequate stability and good extraction reproducibility (<15 % RSD). As a final point, this device is of easy and quick preparation, inexpensive, and suitable for extraction of some PPCPs. Resumen. Se fabricó un nuevo recubrimiento para fibras de microextracción en fase sólida (SPME) utilizando una mezcla del líquido iónico tetrafluoroborato de 1-decil-3metilimidazolio y un adhesivo comercial depositada sobre un soporte de acero inoxidable grabado. El nuevo recubrimiento se caracterizó mediante la aplicación de microscopía óptica y electrónica, espectroscopía de infrarrojo y también se evaluó su capacidad de extracción. La capacidad de extracción se probó utilizando como analitos modelo algunos productos farmacéuticos y de cuidado personal (PPCPs) con diferentes hidrofilicidades. El uso potencial de la nueva fibra se evaluó mediante extracciones en modo de inmersión directa y mostró capacidad de extracción hacia metilparabeno, propilparabeno, naproxeno, diclofenaco y benzofenona-3. Se utilizaron herramientas del diseño experimental para estudiar y optimizar las variables que afectan los procesos de extracción y desorción de la SPME por inmersión directa. El rendimiento analítico del método propuesto se investigó en las condiciones óptimas del procedimiento de SPME, acoplado a un método de cromatografía líquida de alto rendimiento con detector de arreglo de diodos (HPLC-DAD), que fue desarrollado y validado para el análisis de los PPCPs objetivo. El método de SPME por inmersión directa fue lineal, preciso y exacto. Se obtuvieron límites de detección y cuantificación de 0.023 a 0.093 μg mL-1 y 0.118 a 0.279 μg mL-1, respectivamente. Mediante el uso del método desarrollado, se analizaron muestras de agua del grifo y se encontraron recuperaciones de 3.39 a 183.29 %. La nueva fibra presentó una adecuada estabilidad y buena reproducibilidad de extracción (<15 % RSD). Como punto final, este dispositivo es de fácil y rápida preparación, económico y adecuado para la extracción de algunos PPCPs.

Solid-phase microextraction (SPME) is a sample preparation technique with many applications that is being continuously developed. In this technique, the type of fiber coating plays a crucial role for extraction efficiency. Currently available commercial coatings have certain drawbacks that have been overcome by the development of new coatings based on novel materials; these have improved the efficiency of extraction, selectivity and stability of commercial coatings. Pharmaceutical and personal care products (PPCPs) are one of the most important groups of emerging contaminants; however, some studies suggest that these compounds can cause adverse health effects. No official monitoring protocols for these compounds are currently available, so the establishment of analytical methods that allow their determination in environmental samples is required. The complexity of environmental samples together with the low concentration levels of these compounds makes necessary the use of sample preparation techniques capable of removing interferences, as well as preconcentrated analytes, and SPME is a very promising alternative to achieve this. This review describes the recent developments in SPME with classical and novel coatings and its applications for PPCP determination in environmental samples.

Background: The search for new natural or synthetic products with antioxidant activity is commonly based on methods that involve reduction of either 2,2-diphenyl-1-picrylhydrazyl (DPPH) or 2-2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS). However, the reported values of the effective concentrations are highly variable, even in controls. Herein, we optimize and validate both methods of determining antiradical activity. Methods: Optimization was carried out using both a fractionated factorial design and a basic sequential simplex method, by monitoring the reduction percentage. Quercetin or Trolox were used as positive control. Furthermore, for each method, linearity, precision, accuracy, robustness, plate uniformity, signal variability, and Z factor, were established. Results: The optimized conditions for the DPPH method were: DPPH 280 µM in ethanol and 15 min of reaction time in the dark. The linear range was between 7 and 140 µM with an R2 value of 0.9987. The optimized conditions for the ABTS method were: ABTS adjusted to 0.7 absorbance units, 70% concentration in ethanol, and a reaction time of 6 min in the dark. The linear range was found to be between 1 and 70% with an R2 = 0.9991. For both methods, the accuracy and precision were within limits and the Z factor value was higher than 0.89. The applicability of each method was assessed by analyzing eight plant extracts. Conclusion: The DPPH and ABTS reduction methods were optimized and validated on a microscale and could be expected to be implemented in any laboratory.

A new analytical temperature-assisted ionic liquid-based dispersive liquid–liquid microextraction (TA-IL-DLLME) method was developed for glyphosate and aminomethylphosphonic acid determination in water samples. Extracted analytes were derivatized using 9-fluoroenylmethylchloroformate and quantified by liquid chromatography with fluorescence detection. For the TA-IL-DLLME method, two strategies for phase solubilization were evaluated; in approach 1, the ionic liquid and aqueous matrix sample were mixed and then heated, while in approach 2, the aqueous sample was first heated and then the ionic liquid was injected. For both approaches, optimization included parameters that significantly affect extraction efficiency: ionic liquid type and volume, solubilization temperature and time, cooling and centrifugation time. Among the evaluated ionic liquids, 1-decyl-3-methylimidazolium tetrafluoroborate showed the best performance for TA-IL-DLLME and was selected for the two solubilization approaches; with approach 2, slightly better results were obtained. Thus, sample analyses were performed using a procedure based on approach 2. An important matrix effect, attributed to the presence of salts and metals in real water samples was observed. Sample acidification before derivatization allowed this problem to diminish, with recoveries ranging from 75 and 99%, and enrichment factors between 57 and 76 for target analytes. GRAPHICAL ABSTRACT