Herbal bioenhancers are active phytomolecules that increase the bioavailability, bioefficacy and biological activity of various drugs when coadministered at low concentrations. These valuable compounds reduce the dose, increase the treatment rate, decrease the treatment duration, drug resistance or related adverse reactions which have economical implications in livestock and pet medicine. Eventhough the concept of herbal bioenhancers are known for years through Ayurvedic medicine, the underlying mechanisms remains unclear. The main mechanisms involved are related to drug absorption (effect on solubility, drug efflux and transport proteins, increased permeability in gastrointestinal system) and drug metabolism (inhibition/induction of drug metabolysing enzymes, thermogenic effect). Due to species specific differences in these mechanisms, corresponding data on human and laboratory animal could not be attributed. As multidrug resistance is a major treat to both human and animal health, within “One Health” concept, efficient therapeutical strategies are encouraged by authorities, where focus on herbal supplements as a vast unexploited field remains to be researched within “Bioenhancement Concept.” This review brings insight to mechanims involved in bioenhancing effect, examples of herbal extracts and phytoactive compounds and their potential in the veterinary medicine including different classes of drugs such as antibiotics, anticancerous, antiviral, and antituberculosis.

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Environmental estrogen active compounds are strong determinants of estrogen receptor (ER)-positive breast cancers, and increased evidence indicates their contribution to chemotherapy resistance. In the current study, the efficacy of vincristine and tamoxifen, with the presence of diethylhexyl phthalate (DEHP) and bisphenol A (BPA) and the possible involvement of estrogen and estrogen receptor-related mechanisms, was evaluated in an ER+ mammary tumor cancer cell line, MCF-7. Chemotherapeutics tamoxifen as an estrogen receptor modulator and vincristine as an antimitotic compound were selected for evaluation against the presence of common endocrine disrupters. BPA and DEHP preincubation at their proliferative concentrations for 4 h was found to decrease the cytotoxicity of vincristine. mRNA and protein expression of ESR1 and ESR 2 were decreased by vincristine, while this decrease was reversed by DEHP and BPA. Both BPA and DEHP were able to interfere with the cytotoxic activity of vincristine against MCF-7 cells through ESR1 and ESR2. This study provides in vitro toxicological evidence for vincristine resistance and its relation to estrogen active environmental pollutants in ER+ breast cancer cells.

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Vücuttaki endokrin reseptörlerine bağlanıp bunları aktive veya bloke ederek doğal hormonların sentez/parçalanmasını değiştiren endokrin bozucu kimyasallarla ilgili çalışmaların geçmişi 1950'li yıllara kadar gitmektedir. Günümüzde yasaklı olan ama bir dönem yoğun olarak kullanılan organik klorlu pestisitler (OCP), poliklorlu bifeniller (PCB) ve polibromlu difenileterler (PBDE) stabilitelerinin yüksek olması ve yağda birikme özellikleri nedeniyle doğada uzun süre kalmaktadırlar. Bu bileşiklerin biyoakümülasyon ve biyomagnifikasyon nedeniyle gıda zincirine girdikten sonra miktarları sürekli artmaktadır. İnsanların bu kimyasallara maruziyetinin %90'ı bulaşık gıdalarla olmaktadır.