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Additional Supplements That Support Glycemic Control and Reduce Chronic Inflammation
Published in Robert Fried, Richard M. Carlton, Type 2 Diabetes, 2018
Robert Fried, Richard M. Carlton
Not all combinations potentiate. For instance, lipoic acid competes with biotin for binding to the sodium-dependent multivitamin transporter, potentially decreasing the cellular uptake of biotin. Chronic administration of pharmacological doses of lipoic acid have been found to decrease the activities of pyruvate carboxylase and β-methylcrotonyl-CoA carboxylase in rat liver to 64% to 72% respectively, compared to controls (Zempleni, and Mock. 1999a; 1999b).
Pantothenic Acid and Biotin
Published in Judy A. Driskell, Ira Wolinsky, Sports Nutrition, 2005
Gabriela Camporeale, Rocío Rodriguez-Meléndez, Janos Zempleni
Uptake of pantothenic acid into intestinal cells is mediated by the sodium-dependent multivitamin transporter (SMVT).4 This transporter has similar affinity for pantothenic acid, biotin and lipoic acid.4–6 At high intestinal concentrations of pantothenic acid, absorption by passive diffusion is quantitatively more important than active transport.7 It remains unknown whether bacterial synthesis in the intestine contributes substantially to pantothenic acid supply. Note that SMVT is also expressed in the colon, where the bulk of intestinal microorganisms reside. If microbial synthesis of pantothenic acid is substantial, balance studies in humans may have underestimated pantothenic acid turnover and requirements. The bioavailability of pantothenic acid from dietary sources is about 50% compared with synthetic pantothenate from vitamin supplements.8 If supraphysiological doses of synthetic pantothenic acid (10–100 mg/day) are ingested orally, about 60% are excreted into urine.9
Enhancement of the anticancer effect of atorvastatin-loaded nanoemulsions by improving oral absorption via multivalent intestinal transporter-targeting lipids
Published in Drug Delivery, 2022
Laxman Subedi, Prashant Pandey, Bikram Khadka, Jung-Hyun Shim, Seung-Sik Cho, Seho Kweon, Youngro Byun, Ki-Taek Kim, Jin Woo Park
Alternatively, for enhanced intestinal permeation, the surface modification of nanocarriers with various moieties targeting intestinal membrane transporters (e.g., peptide transporter, glucose transporter, apical sodium-dependent bile acid transporter [ASBT], and sodium-dependent multivitamin transporter [SMVT]) has been introduced to facilitate drug transport (Pangeni et al., 2021). In our previous study, we improved the oral absorption of poorly permeable drugs by ionic complex formation with a positively charged bile acid derivative via ASBT-mediated transport (Deng & Bae, 2020; Li et al., 2020; Pangeni et al., 2020; Subedi et al., 2022). Additionally, we constructed docetaxel- and etoposide-loaded nanoemulsive systems to increase aqueous solubility and intestinal permeability by physically anchoring deoxycholic acid (DOCA) in an ionic complex with the cationic lipid, 1,2-dioleyl-3-trimethylammonium propane (DOTAP) (DOCA-DOTAP); we confirmed 249% and 1752% greater oral bioavailabilities, respectively, compared to the free drugs via ASBT-mediated endocytosis (Jha et al., 2020a; Jha et al., 2020b)
Development of novel biotinylated chitosan-decorated docetaxel-loaded nanocochleates for breast cancer targeting
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Ishwor Poudel, Raj Ahiwale, Atmaram Pawar, Kakasaheb Mahadik, C. Bothiraja
The exploration of active targeting techniques using ligands is getting popular as well as efficient for quite of a time now. The selectivity of ligands to cancerous cells averts the toxicity problem to healthy tissues and ensures maximum efficacy of the therapy. Biotin (BI) has been used as a targeting moiety over drug-loaded carriers like liposomes [18], dendrimers [19] and nanoparticles [20,21] designed to increase cellular uptake in tumour cells. BI receptors are over expressed in the majority of cancer cells like breast cancer, prostate cancer, pancreatic cancer and ovarian cancer [19]. BI is water soluble vitamin (vitamin H) having essential roles involving cell growth, signal transduction and many other cellular functions. BI is internalized into the cells through binding to the sodium-dependent multivitamin transporter (SMVT) present over cancer cell surfaces [22,23]. As cancer cells are under rapid proliferation, the transporters are highly expressed which desires more BI for rapid cell divisions. The use of BI as targeting moiety and NCs as carrier can ensures the selectivity and deliverability as well as stability of the formulation.
Metabolism of bioconjugate therapeutics: why, when, and how?
Published in Drug Metabolism Reviews, 2020
Hanlan Liu, Jayaprakasam Bolleddula, Andrew Nichols, Lei Tang, Zhiyang Zhao, Chandra Prakash
ACV, a guanosine analog, has been the standard first-line drug for prophylaxis and treatment of herpes simplex virus (HSV). In HSV-infected cells, ACV is converted to ACV monophosphate by viral thymidine kinases. The monophosphate derivative is then subsequently phosphorylated by cellular kinases to ACV triphosphate, which then serves as a substrate and a chain terminator for viral DNA polymerase. However, ACV has poor permeation across the cornea due to its hydrophilic nature. Vadlapudi and coworkers synthesized 5 biotinylated lipid prodrugs, namely biotin-ricinoleic acid-ACV (B-R-ACV), biotin-12-hydroxystearic acid-ACV (B-12HS-ACV), biotin-ACV (B-ACV), ricinoleic acid-ACV (R-ACV), and biotin-ricinoleic acid-ACV (12HS-ACV), all of which targeted the sodium-dependent multivitamin transporter on the cornea to facilitate an enhanced cellular absorption of ACV. They showed a sodium-dependent cellular accumulation of biotinylated lipid ACV prodrugs in human corneal epithelium cells and better ocular tissue (i.e. cornea, iris-ciliary body, and lens) stability of the lipid prodrugs (i.e. B-R-ACV and B-12HS-ACV) compared to non-lipidated but biotinylated prodrugs (i.e. B-ACV). The esterase activity in cornea is highly relevant since HSV establishes long-term latency in the cornea and the cornea acts as a major permeation pathway for topically administered drugs. B-R-ACV and B-12HS-ACV were more effective against HSV-1 and HSV-2 than ACV due to the synergistic effect of enhanced uptake via the sodium-dependent multivitamin transporter and cellular permeability. These biotinylated lipid prodrugs of ACV have not been tested in the clinic yet.