Presently the search for new drugs from natural resources is of growing interest to the pharmaceutical industry. Natural products have been the source of new drugs since ancient times. Plants are a good source of secondary metabolites which have been found to have beneficial properties. The present study is a review of the chemistry and pharmacology of Citrus sinensis. This review reveals the therapeutic potential of C. sinensis as a source of natural compounds with important activities that are beneficial for human health that could be used to develop new drugs.

Human skin works as a barrier against the adverse effects of environmental agents, including ultraviolet radiation (UVR). Exposure to UVR is associated with a variety of harmful effects on the skin, and it is one of the most common health concerns. Solar UVR constitutes the major etiological factor in the development of cutaneous malignancy. However, more than 90% of skin cancer cases could be avoided with appropriate preventive measures such as regular sunscreen use. Plants, constantly irradiated by sunlight, are able to synthesize specialized molecules to fight against UVR damage. Phenolic compounds, alkaloids and carotenoids constitute the major plant secondary metabolism compounds with relevant UVR protection activities. Hence, plants are an important source of molecules used to avoid UVR damage, reduce photoaging and prevent skin cancers and related illnesses. Due to its significance, we reviewed the main plant secondary metabolites related to UVR protection and its reported mechanisms. In addition, we summarized the research in Mexican plants related to UV protection. We presented the most studied Mexican plants and the photoprotective molecules found in them. Additionally, we analyzed the studies conducted to elucidate the mechanism of photoprotection of those molecules and their potential use as ingredients in sunscreen formulas.

Equisetum myriochaetum is a semi-aquatic plant found on riverbanks that is commonly used in traditional medicine as a diuretic agent. Additionally, the genus Equisetum stands out for its content of the flavonoid kaempferol, a well-known antiproliferative agent. Therefore, in this study, E. myriochaetum ethanolic extract was tested in vitro against a cervical cancer cell line (SiHa). Additionally, the antioxidative activity was evaluated through a 2,2-diphenyl-1-picrilhidrazil (DPPH) assay. Finally, a molecular docking analysis of apigenin, kaempferol, and quercetin on the active site of β-tubulin was performed to investigate their potential mechanism of action. All fractions of E. myriochaetum ethanolic extract showed antioxidative activity. Fraction 14 displayed an antiproliferative capacity with a half maximal inhibitory concentration (IC₅₀) value of 6.78 μg/mL against SiHa cells.

Background/Objectives: The formulation of microspheres for lipophilic drugs using aqueous methods, such as spray drying, faces significant challenges. The main objective of this study was to evaluate the effect of the process parameters and polymer selection on the production of microspheres by spray drying for a lipophilic drug. Methods: Lipophilic drug-loaded microspheres were developed using various polymers via the aqueous spray drying method. The effects of the factors on the yield percentage and encapsulation efficiency were analyzed. Microspheres preparation included Agave inulin, guar gum, hydroxypropyl methylcellulose, and Eudragit^® S100. A 2³ factorial design was performed, and the parameters were optimized. Results: Inlet temperature, feed flow, and polymer percentage showed a significant effect (p < 0.05) on the yield percentage of guar gum microspheres and encapsulation efficiency of the inulin microspheres. Inulin and guar gum microspheres showed the best yield percentage (75.41%) and encapsulation efficiency (100%), respectively. In addition, guar gum microspheres had the best morphology, and hydroxypropyl methylcellulose microspheres were smaller and had an irregular surface. Eudragit did not maintain its delayed release property due to limitations of the aqueous method; inulin released the drug immediately, and guar gum and hydroxypropyl methylcellulose microspheres prolonged release only by a few additional hours. Conclusions: The experimental design showed that optimizing the parameters (inlet temperature, feed flow, and the type and percentage of polymer) can regulate the microsphere development process to obtain improved product yield and encapsulation efficiency results.

Metabolic reprogramming in cancer is considered to be one of the most important hallmarks to drive proliferation, angiogenesis, and invasion. AMP-activated protein kinase activation is one of the established mechanisms for metformin’s anti-cancer actions. However, it has been suggested that metformin may exert antitumoral effects by the modulation of other master regulators of cellular energy. Here, based on structural and physicochemical criteria, we tested the hypothesis that metformin may act as an antagonist of L-arginine metabolism and other related metabolic pathways. First, we created a database containing different L-arginine-related metabolites and biguanides. After that, comparisons of structural and physicochemical properties were performed employing different cheminformatic tools. Finally, we performed molecular docking simulations using AutoDock 4.2 to compare the affinities and binding modes of biguanides and L-arginine-related metabolites against their corresponding targets. Our results showed that biguanides, especially metformin and buformin, exhibited a moderate-to-high similarity to the metabolites belonging to the urea cycle, polyamine metabolism, and creatine biosynthesis. The predicted affinities and binding modes for biguanides displayed good concordance with those obtained for some L-arginine-related metabolites, including L-arginine and creatine. In conclusion, metabolic reprogramming in cancer cells by metformin and biguanides may be also driven by metabolic disruption of L-arginine and structurally related compounds.

Cancer cells resort to metabolic reprogramming to sustain proliferation. Lung cancer has one of the highest mortality rates of all types of cancer. An important factor in its high mortality rate is its tumors’ ability to undergo significant metabolic reprogramming. Phytochemicals can counteract this altered metabolism and exhibit anticancer properties. Coleus hadiensis, a plant used in traditional medicine, has shown such potential. This study evaluated the in vitro cytotoxic activity of its methanolic extract and its effects on the metabolism of HTB-177 lung cancer cells. Qualitative and quantitative phytochemical analysis of this extract was performed to characterize its main constituents. Lung cancer cells were treated with different extract concentrations to evaluate their response to the extract. Cytotoxicity was determined using an MTT assay, and metabolites were analyzed through ¹H-NMR spectroscopy combined with multivariate statistical analysis. Transcriptomic profiling was also conducted to assess gene expression changes in metabolic pathways. Three main phenolic compounds were identified in the extract. The HPLC profile revealed peaks corresponding to gallic acid (GA), ferulic acid (FA), and rosmarinic acid (RA). The extract exhibited cytotoxic activity with an IC₅₀ of 192.85 µg/mL. Metabolic alterations were observed mainly in glycolysis, the Krebs cycle, and lipid metabolism—key pathways for tumor growth. Transcriptomic data revealed altered metabolism-related genes. The upregulation of ME1 correlated with the observed increase in pyruvate levels, while the downregulation of ALDH7A1 and ASRGL1 was linked to altered amino acid catabolism. Furthermore, transcriptomic data revealed the upregulation of the pro-apoptotic gene HRK. These results indicate that the methanolic extract of C. hadiensis possesses cytotoxic activity against lung cancer cells by modulating central metabolic routes and gene expression linked to cancer cell survival and proliferation.