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Phototherapy Using Nanomaterials
Published in D. Sakthi Kumar, Aswathy Ravindran Girija, Bionanotechnology in Cancer, 2023
A. N. Resmi, V. Nair Resmi, C. R. Rekha, V. Nair Lakshmi, Shaiju S. Nazeer, Ramapurath S. Jayasree
Albumin is a plasma protein, which is responsible for blood colloidal osmotic pressure. This is non-antigenic and biodegradable and has been studied extensively as a drug carrier. The average HSA half-life is 19 days [177]. The photosensitizer pheophorbide was loaded on human serum albumin (Pheo-HSA) nanoparticles with different cross-linked ratios by non-covalent adsorption. Intracellular uptake and phototoxicity of both pheophorbide and Pheo-HSA nanoparticles were studied in Jurkat cells. For irradiation, a laser diode with emission at 668 nm and a light dose of 96 mJ/cm2 were used as light source. Due to intramolecular interactions, 1O2 quantum yield of pheophorbide-loaded HSA nanoparticles was very low and the final phototoxicity was at the same level as induced by free pheophorbide [178].
Wild Plants of Northern Peru
Published in Mahendra Rai, Shandesh Bhattarai, Chistiane M. Feitosa, Wild Plants, 2020
Fidel A. Torres-Guevara, Mayar L. Ganoza-Yupanqui, Luz A. Suárez-Rebaza, Gonzalo R. Malca-García, Rainer W. Bussmann
Muehlenbeckia hastulata, commonly known as quilo mollaca and voqui, has been used for a long time in Peru, Argentina, and Chile as a diuretic, hypotensive, antihemorragic, sedative, and for reumatism treatment and burns. The chemical composition of the aerial part shows the presence of tannins, flavonoids, and anthraquinones (Figure 3.6) (Erazo et al. 2002, Mellado et al. 2012, 2013). The crude extract of quilo reported antioxidant activity on 2, 2-diphenyl-1-pycrylhydrazil (DPPH) assay (Mellado et al. 2012). Interestingly, crude extract was evaluated in vitro for the biological activity against influenza virus proliferation in MDCK cells. On the other hand, three active compounds responsible for the biological activity, such as pheophorbide A, hepericin, and protohypericin were determined (Figures 3.7–3.14) (Yasuda et al. 2010).
Marine-Algal Bioactive Compounds
Published in Gokare A. Ravishankar, Ranga Rao Ambati, Handbook of Algal Technologies and Phytochemicals, 2019
Iahtisham Ul-Haq, Masood Sadiq Butt, Natasha Amjad, Iqra Yasmin, Hafiz Ansar Rasul Suleria
Among bioactive compounds of algae, its natural pigments, phlorotannins, diterpenes and sulfated polysaccharides have gained significant importance. Algae being a photosynthetic organism contains chlorophylls as a major pigment (Chen et al. 2017). This pigment is converted to pheophorbide, pheophytin and pyropheophytin upon processing which possess plausible cancer preventive perspectives (Chen and Roca 2018a; Chen and Roca 2018b). Among other things, pheophytin has been found to acquire more cytotoxic effects than pheophorbide (Lin et al. 2014). The content of pigments is season dependent as are most of the fucoxanthin, violaxanthin, chlorophyll A and carotene in brown algae (Ascophyllum). Similar seasonal variation is also present in Fucus serratus where lower levels are seen during autumn. Moreover, chlorophyll contents are also influenced with the light exposure as harbored algae showed more pigment as compared to openly grown algae (Chen and Roca 2018b).
Recent advances towards natural plants as potential inhibitors of SARS-Cov-2 targets
Published in Pharmaceutical Biology, 2023
Zhouman He, Jia Yuan, Yuanwen Zhang, Runfeng Li, Meilan Mo, Yutao Wang, Huihui Ti
It is important to improve the effective utilization and application of natural products from Chinese medicine. Generally, activity-guided fractionation leads to the isolation of active pure compounds. Crude extracts can be fractionated into subfractions that are more suitable for high-performance liquid chromatography systems and analyzed by using nuclear magnetic resonance (NMR) spectrometry and liquid chromatography-high-resolution mass spectrometry. For example, Jimenez-Aleman et al. (2021) identified the antiviral metabolite as pheophorbide A (PheoA) from Marchantia polymorpha L. (Marchantiaceae) by using a bioactivity-guided chromatographic approach. These analytical approaches coupled with computational approaches generate natural product structures or spectral data. Various chemometric methods, such as principal component analysis, support vector machines, artificial neuronal networks and so on, correlate signals in NMR and MS data with the measured activity. These approaches might accelerate the identification of bioactive natural products. For example, Darwish et al. (2022) used UPLC-MS/MS coupled with chemometric analysis to detect chemical composition differences among different Lantana camara L. (Verbenaceae) (a widespread plant) cultivars extracts and correlated them to COVID-19 inhibitory activities allowing to determine possible biomarkers (Figure 1).
Phototherapeutic effect of transformable peptides containing pheophorbide a on colorectal cancer
Published in Drug Delivery, 2022
Zhiqin Zhang, Kaixin Wang, Manting Liu, Panxiang Hu, Yuchen Xu, Dongge Yin, Yuchang Yang, Xiaoxv Dong, Changhai Qu, Lu Zhang, Jian Ni, Xingbin Yin
Therefore, based on the self-assembled fibrils of KLVFF (Pham et al., 2014; Li et al., 2016; Yu et al., 2016; Zhang et al., 2020), we reported a new strategy to improve the biological properties of the photosensitizer (Scheme 1). Specifically, a smart transformable peptide monomer (GRGDLGRL-KLVFF-GGK-PheoA) was designed and synthesized. It consisted of three key parts, including (1) the hydrophilic core GRGDLGRL, which showed a high targeting ability toward the integrin αvβ6 protein on the tumor cell surface (Roesch et al., 2018), (2) the KLVFF, which can transform into nanofibrils through β-sheet (Li et al., 2016; Zhang et al., 2020), and (3) pheophorbide a (PheoA), a photosensitizer with the fluorescent ability (Xodo et al., 2012; Saide et al., 2020). Peptide GGK acted as a linker, which could be used to connect PhoeA, because lysine (K) has two amino groups, one of which could be used for dehydration condensation with the carboxyl group of PhoeA. In an aqueous condition, the peptide monomer self-assembled into nanoparticles (NPs) under the force of hydrophobic interaction. PheoA and the peptide KLVFF acted as lipophilic groups, and the peptide GRGDLGRL acted as the hydrophilic group in this process. The NPs displayed further transformation into nanofibrils (NFs) after NPs combination with the integrin αvβ6 protein on the HT-29 cancer cell surface with the help of the β-sheet-forming peptide KLVFF. We proved that the nanofibrillar aggregated state of PheoA was propitious to the pursuance of light-to-energy conversion efficiency, ROS generation, and tumor retention, which enhanced the inhibitory effect on tumors.
Modulating barriers of tumor microenvironment through nanocarrier systems for improved cancer immunotherapy: a review of current status and future perspective
Published in Drug Delivery, 2020
Huanrong Lan, Wei Zhang, Ketao Jin, Yuyao Liu, Zhen Wang
Wang et al. (2013) designed combining several features including ultra-pH-sensitive diblock (PDPA), and siRNA and pheophorbide A photosensitizer (PPa), may improve therapeutic ability. Hydrolyzed amphiphilic polycation, e.g. 1,2-epoxytetradecane alkylated oligoethylenimine (OEI-C14), having an intrinsic binding affinity with siRNA, thereby promoting proton sponge to ensure the endosomal escape of siRNA. PDPA-OEI-C14-PPa (POP) micelleplex was activated precisely in acidic pH (6.2) while maintaining an intact epithelial microenvironment. The pdna-PD-L1-conjugated micelleplexes (POP-PD-L1) efficiently triggered blockade of PD-L1 and therefore rescued the tumor cells from immunosuppression through silencing the expression of PD-L1. The immune reaction to antitumor was intensified by photodynamic therapy (PDT), where it effectively eradicated the tumor and remote metastasis in the B16-F10 melanoma model through encouraging cytokine production (TNF-α and IFN-ÿ) and tumor invasion lymphocyte frequency (CD8+ and CD4+). Within a week of combination therapy, its most apoptotic cancer death was observed than individual modalities and was thus ultimately caused by the existence of activated immune cells.