Food as medicine
Geoffrey P. Webb in Nutrition, 2019
Plants do not produce cholesterol but they do produce a range of steroids which are very similar in chemical structure to cholesterol and are collectively termed phytosterols. The most prevalent of these plant sterols are called β-sitosterol and campesterol which make up over 80% of total dietary phytosterols. Other phytosterols include stigmasterol and the fungal steroid ergosterol which when irradiated with UV light yields vitamin D2. The average daily intake of these plant sterols is normally around 100–300 mg in the UK with the highest intakes in vegetarians. These plant sterols are structurally very similar to cholesterol e.g. the only difference between cholesterol and β-sitosterol is that the latter has an extra ethyl (CH3CH2) group attached to carbon 24 of cholesterol. Cholesterol and most plant sterols have a double bond in one of the rings of the steroid nucleus (between carbons 5 and 6). A tiny proportion of the plant sterols in the diet do not have this double bond and are sometimes termed the saturated phytosterols or the (phyto)stanols– these structures are exemplified in Figure 14.3 which shows the structures of cholesterol, β-sitosterol and β-sitostanol.
Pharmacognosy and Pharmacopoeial Standards for Syzygium cumini
K. N. Nair in The Genus Syzygium, 2017
The yield and physical characteristics of the leaf oil vary according to the season of collection. The essential oil is reported to be responsible for the antibacterial activity of the leaves of S. cumini (Anonymous 2002; Jagetia and Baliga 2002). Stem bark contains pentacyclic triterpenoid betulinic acid (m.p. 306°C–310°C) (Anonymous 2002; Ivan 2006). Betulinic acid is a naturally occurring triterpenoid, which has shown selective cytotoxicity against a number of specific tumors and promising activity against HIV, malaria, and demonstrated immunomodulatory as well as inflammatory actions. A plant sterol, β-sitosterol, is found in almost all parts of the plant. It has the same chemical structure as cholesterol. It has very beneficial pharmacological activity, for example, as an anti-inflammatory and in lowering blood cholesterol (Wang and Ng 1999; Yun et al. 2003). Friedelin (C30H50O, m.p. 256°C–260°C) is also a pentacyclic triterpenoid found in plants (Anonymous 2002; Ivan 2006). Plant bark also contains a substance that is an ester of epi-friedelanol (C30H51OH) with a fatty acid (C27H55COOH). It also contains tannins (10%–12%), gallic acid, ellagic acid, and the resin myricetin (Bhatia and Bajaj 1972).
Plant sterols
Linda M. Castell, Samantha J. Stear (Nottingham), Louise M. Burke in Nutritional Supplements in Sport, Exercise and Health, 2015
Sitosterol is the most abundant phytosterol in plants and consequently in Western diets. Ultramarathon runners supplemented with β-sitosterol capsules displayed fewer cellular markers of inflammation (particularly those related to neutrophils) after a race compared with placebo-treated controls, suggesting that phytosterols may mitigate the effects of acute, strenuous exercise on immunity (Bouic et al., 1999). However, in a study of trained runners subjected to an exercise bout of increasing intensity until exhaustion, heart rate and blood lactate were uninfluenced by phytosterols (Timmons et al., 2000). In a study of older sedentary adults, six months of endurance training reduced plasma cholesterol levels while increasing the absorption of phytosterols contained in a normal diet (Wilund et al., 2009), suggesting that phytosterols may have beneficially regulated plasma lipids. A separate study of middle-aged and older-aged sedentary adults demonstrated that eight weeks of endurance training combined with sitosterol supplementation was associated with decreases in blood low density lipoproteins and triglycerides, but increases in high density lipoproteins, effects that were more strongly manifest when exercise and sitosterol therapies were combined (Varady et al., 2004).
Assessments of in vitro and in vivo antineoplastic potentials of β-sitosterol-loaded PEGylated niosomes against hepatocellular carcinoma
Published in Journal of Liposome Research, 2020
Raquibun Nisha, Pranesh Kumar, Anurag Kumar Gautam, Hriday Bera, Bolay Bhattacharya, Poonam Parashar, Shubhini A. Saraf, Sudipta Saha
β-sitosterol (BS) is a plant-derived sterol molecule and structurally similar to cholesterol (Novotny et al.2017). It induces apoptosis by augmenting FAS levels and caspase-8 activity and by promoting phosphorylation of extracellular signals, which typically regulate kinase (ERK) and P38-MITOGEN ACTIVATED PROTEIN KINASE (MAPK) (Awad et al.2007, Moon et al.2007). Moreover, BS decreases the generation of free radicals due to its high oxidation potential (antioxidant property) and modulates the antioxidant enzyme levels such as liver lipid peroxides, which are affected during the pathogenesis of cancer (Moreno 2003, Vivancos and Moreno 2005). The antioxidants facilitate in maintaining oxidative stress which further prevents the generation of free radicals inhibiting any kind of biological alteration in the tissue/organ. It also inhibits cancer cell proliferation at low concentrations without causing the cytotoxic to non-cancerous cells (Jayaprakasha et al.2007). Particularly, BS is a potent growth inhibitor of human colon (HT-29) and prostate (LNCaP) cancer cells (Awad et al.1996, Bin Sayeed and Ameen 2015, von Holtz et al.1998).
Bridelia ferruginea inhibits key carbohydrate digesting enzyme and intestinal glucose absorption and modulates glucose metabolism in diabetic rats
Published in Archives of Physiology and Biochemistry, 2023
Olajumoke Oyebode, Lindiwe Zuma, Ochuko Lucky Erukainure, Neil Koorbanally, Md. Shahidul Islam
2-Methoxy-3–(2-propenyl) phenol found solely present in the aqueous fraction has been reported for its cytotoxic activity (Espineli et al. 2014), while pyrogallol has been reported to act as an anti-inflammatory agent (Nicolis et al. 2008). Phytol acetate has been reported for its ability to alleviate insulin resistance (Nicolis et al. 2008). Of utmost importance however is the sitosterol identified in the butanol, DCM and ethyl acetate fractions (Figure 8, Table 5). Sitosterol is a dietary phytosterol mainly found in plants, and studies have elucidated its anti-diabetic activity (Gupta et al. 2011, Balamurugan et al. 2011, Karan et al. 2012, Zeb et al. 2017). The presence of sitosterol and other identified phytochemicals in B. ferruginea may contribute synergistically to the antidiabetic, antihyperlipidemic and nephroprotective effects of the butanol fraction.
Effects of Lespedeza Cuneata aqueous extract on testosterone-induced prostatic hyperplasia
Published in Pharmaceutical Biology, 2019
Bong Kyun Park, Chang Won Kim, Jeong Eun Kwon, Manorma Negi, Yong Tae Koo, Sang Hun Lee, Dong Hyun Baek, Yoo Hun Noh, Se Chan Kang
Lespedeza cuneata G. Don (Fabaceae) is a species of flowering plant native to Asia and eastern Australia. L. cuneata is used as a traditional herbal medicine for asthma, abscesses, breast cancer, and protection of liver and kidney function (Ahn 1998). Several studies have indicated that it has therapeutic effects on diabetes, low stamina and amblyopia (Huang 1998). Its bioactive components include β-sitosterol, quercetin, kaempferol, pinitol, avicularin, juglanin and trifolin, among others (Matsuura et al. 1978). These are known to have antioxidant, anti-inflammation and anticancer effects. In particular, β-sitosterol has the potential to inhibit BPH and high blood cholesterol levels (Wilt et al. 1999; Rudkowska et al. 2008). Roots and leaves of L. cuneata also contain minerals, amino acids, vitamins and flavonoids, suggesting that extracts of the leaves may have antioxidative and anti-inflammatory effects (Ding et al. 2006; Deng et al. 2007; Kim & Kim 2010). Although many previous studies have examined the pharmacological effects of L. cuneata, the pharmacological effects of an aqueous extract of L. cuneata (LCW) on testosterone-induced prostatic hyperplasia (TPH) have not been explored.
Related Knowledge Centers
- Benign Prostatic Hyperplasia
- Boldenone
- Chemical Structure
- Phytosterol
- Vegetable Oil
- Cholesterol
- Food Additive
- Stigmasterol-Rich Plant Sterols
- Nut
- Sitosterolemia