Medicinal Plants: A Potent Antimicrobial Source and An Alternative to Combat Antibiotic Resistance
Jayanta Kumar Patra, Gitishree Das, Sanjeet Kumar, Hrudayanath Thatoi in Ethnopharmacology and Biodiversity of Medicinal Plants, 2019
In 1942, the first peptides were reported having inhibitory effect on microorganisms (Balls, Hale and Harris, 1942). They contain disulfide bond and have positive charge (Zhang and Lewis, 1997). They inhibit the activity of microbes either by forming ion channels in microbial membrane or by inhibiting the action of enzymes and protein present inside the microbes. Thionins are active peptides used against yeast and bacteria (De Caleya et al., 1972). As per reports some of the thionin derivatives are potential agents against fungi but not for bacteria (Kragh et al., 1995). A newly identified peptide residue fabatin inhibit E. coli, P. aeruginosa as well as Enterococcus hirae but are not active against Candida or Saccharomyces (Zhang and Lewis, 1997). Lectins are proteins present in nature and in many plant species. They are generally active against viral infections (Balzarini et al., 1991). Few useful antimicrobial plant compounds are summarized in Table 12.5.
Growth Factor Receptors
Enrique Pimentel in Handbook of Growth Factors, 2017
Lateral mobility and aggregation (clustering) of growth factor-receptor complexes on the cell surface are important for the physiological activities of many of these agents. Plant lectins such as concanavalin A or wheat germ agglutinin are multivalent molecules that bind to specific carbohydrates on the cell surface and can crosslink various cell surface receptors. Lectins may display striking effects at the level of the plasma membrane. They may decrease EGF- and insulin-stimulated DNA synthesis.46 A close relationship between receptor aggregation/immobilization and response has been observed in a number of cellular systems. For many cell surface receptors, crosslinking by antireceptor antibodies is sufficient for receptor activation. This is not a general rule, however. The NGF receptor is preclustered and immobile on responsive cells, which suggests that immobilization of the receptor prior to ligand binding is required for signal transduction.47 In general, there are two classes of cell surface receptors: those that are preclustered and immobile and those that only become clustered and immobile upon ligand binding.
Medicinal Mushrooms
Anil K. Sharma, Raj K. Keservani, Surya Prakash Gautam in Herbal Product Development, 2020
Lectins have been demonstrated to have anticancer activities with both in vitro experiments and in clinical trials (Liu et al., 2010). They function by binding to membrane carbohydrates. Its therapeutic purpose is to bind to the membrane of a mutant cell or its receptors, leading to the death of the cancer cells and therefore, encouraging the reduction of tumor (Cheung et al., 2012; Wang et al., 1995). Lectins can also ameliorate the unwanted side effects that usually accompany chemotherapy in addition to their ability to eradicate tumor cells by increasing the activities of tumor-infiltrating lymphocytes (Cheung et al., 2012).
An Overview of Hepatocellular Carcinoma with Emphasis on Dietary Products and Herbal Remedies
Published in Nutrition and Cancer, 2022
Deepa S. Mandlik, Satish K. Mandlik
The research looked at the anti-proliferative properties of aqueous extracts from French bean aerial sections (Phaseolus vulgaris). The aqueous extracts showed strong antioxidant activity at 400 and 800 mg/mL doses and inhibited the development of HepG2 cells (62). The seed coats of P. vulgaris yielded several compounds, including triterpenoids and flavonoids, according to phytochemical review. Several compounds isolated from P. vulgaris showed anti-proliferative activity (63). The lectins are the most common protein found in legumes. Due to its assorted pharmacological roles such as antitumor, anti-HIV and antibacterial properties, lectin has gained a lot of attention as a therapeutic agent in recent years. The hemagglutinin extracted from the seeds of P. vulgaris had a moderate inhibitory effect on HepG2 cell growth but did not affect normal liver cells (64). According to their research, BTKL’s (legume lectin from the seeds) antitumor activities against HepG2 cells may be mediated by three mechanisms as inducing apoptosis and necrosis, promoting nitric oxide development through upregulation of iNOS and triggering the release of proinflammatory cytokines such as interleukin (IL)-1, IL-2, tumor necrosis factor (TNF)-α and Interferon (INF)-γ (65). A hemagglutinin isolated from P. vulgaris was found to have greater anti-proliferative activity than concanavalin A in the HepG2 cancer cells (66).
Novel approaches to glycomimetic design: development of small molecular weight lectin antagonists
Published in Expert Opinion on Drug Discovery, 2021
Vishnu C. Damalanka, Amarendar Reddy Maddirala, James W. Janetka
Lectins are carbohydrate-binding proteins that are found in most organisms ranging from viruses and bacteria to other parasites and to plants and mammals including humans [1]. They are critical to numerous biological processes such as cell adhesion [2], fertilization [3], migration [4], virulence [5], inflammatory responses [6], lysosomal storage [7], and several other functions [8,9]. Microorganisms (bacteria, viruses, and other parasites) utilize lectins to recognize specific carbohydrates on the extracellular surface of host cells to bind and invade (infect) the cells, which also prolongs their survival by protection from the immune system. Lectins, both mammalian and non-mammalian, have been widely studied for their involvement in both pathogenic and nonpathogenic processes [10,11]. Hundreds of lectins have been identified to date [12,13] and while some of them are recognized as promising drug targets for anti-infective and anticancer therapy, only a limited number of lectins have been thoroughly studied, and as a result, only a small number of them have been validated and realized practically as therapeutic targets.
Improving cellular uptake of therapeutic entities through interaction with components of cell membrane
Published in Drug Delivery, 2019
Renshuai Zhang, Xiaofei Qin, Fandong Kong, Pengwei Chen, Guojun Pan
Lectins are glycoproteins possessing at least one non-catalytic domain, which bind reversibly to specific mono- or oligosaccharides of the cell membrane (Peumans & Van Damme, 1995). Typically involving a high number of binding sites and determined by a specific sugar code, lectin binding is usually rapid and strong. Based on the outstanding binding properties, lectin-mediated drug delivery may become a promising strategy to improve the efficacy of poorly permeable drugs. Gabor et al. found that the dietary lectin wheat germ agglutinin can facilitate binding and uptake of protein drugs due to its cytoadhesive and cytoinvasive properties (Gabor et al., 2002). However, the potential disadvantage of natural lectins is of large size that results in immunogenicity and toxicity when they were used as drug carriers (Lehr & Gabor, 2004). One of the probable methods to overcome these problems is to design smaller peptides or even organic small molecules which can mimic the function of lectins. Several small size lectins (peptides) have been found, and shown better performance than natural lectins (Lü et al., 1999; Wang et al., 2003; Li et al., 2008). For example, odorranalectin, a lectin-like peptide from skin secretions of Odorrana grahami, showing extremely low toxicity and immunogenicity in mice (Li et al., 2008). However, the study of utilizing lectins as drug carriers was very little in recent 10 years compared to CPP and antibody delivery systems which have been discussed in above part. More efforts need to be put into the design field of lectins mimic before the ideal mimics were available.
Related Knowledge Centers
- Agglutination
- Bacteria
- Polysaccharide
- Protein
- Ricin
- Toxin
- Virus
- Carbohydrate
- Moiety
- Glycoconjugate