Dietary glucosinolates derived isothiocyanates: chemical properties, metabolism and their potential in prevention of Alzheimer's disease

Alzheimer's disease (AD) is the most prevalent form of dementia affecting millions of people worldwide. It is a progressive, irreversible, and incurable neurodegenerative disorder that disrupts the synaptic communication between millions of neurons, resulting in neuronal death and functional loss due to the abnormal accumulation of two naturally occurring proteins, amyloid β (Aβ) and tau. According to the 2018 World Alzheimer's Report, there is no single case of an Alzheimer's survivor; even 1 in 3 people die from Alzheimer's disease, and it is a growing epidemic across the globe fruits and vegetables rich in glucosinolates (GLCs), the precursors of isothiocyanates (ITCs), have long been known for their pharmacological properties and recently attracted increased interest for the possible prevention and treatment of neurodegenerative diseases. Epidemiological evidence from systematic research findings and clinical trials suggests that nutritional and functional dietary isothiocyanates interfere with the molecular cascades of Alzheimer's disease pathogenesis and prevent neurons from functional loss. The aim of this review is to explore the role of glucosinolates derived isothiocyanates in various molecular mechanisms involved in the progression of Alzheimer's disease and their potential in the prevention and treatment of Alzheimer's disease. It also covers the chemical diversity of isothiocyanates and their detailed mechanisms of action as reported by various in vitro and in vivo studies. Further clinical studies are necessary to evaluate their pharmacokinetic parameters and effectiveness in humans.

Histochemical and histomorphological evidence of the modulating role of 1-isothiocyanate-4-methyl sulfonyl butane on cisplatin-induced testicular-pituitary axis degeneration and cholesterol homeostasis in male Sprague-Dawley rats

BACKGROUND

This study examine the histochemical and histomorphological effect of 1-isothiocyanato-4-methyl sulfonyl butane (SFN) on cisplatin (CP) induced testicular alteration and cholesterol homeostasis.

MATERIALS AND METHODS

Ninety adult-male Sprague-Dawley rats were randomized into nine groups of ten (n=10) rats each. Group A (control) received normal saline, group B received a single dose of 10mg/Kg body weight (bwt) CP (i.p.), group C received 50mg/Kg bwt of SFN, group D received 100mg/Kg bwt of SFN, group E received 10mg/Kg bwt CP and 50mg/Kg bwt of SFN, group F received 10mg/Kg bwt CP and 100mg/Kg bwt of SFN, group G received 10mg/Kg bwt CP and 50mg/Kg bwt vitamin C, group H received 50mg/Kg bwt of SFN and 10mg/Kg bwt CP, group I received 100mg/Kg bwt of SFN and 10mg/Kg bwt CP. The procedure lasted for 56 days. Testicular histomorphology and histochemistry, testicular testosterone, sperm parameters, total antioxidant status (TSA), total oxidant status (TOS), oxidative stress index (OSI), and serum lipid profile were examined.

RESULTS

Cisplatin decrease intra-testicular testosterone, sperm quality, and expression of glycogen and increases testicular TOS and OSI, serum lipid profile, collagen, and disruption of germinal epithelium. However, the intervention of SFN reversed the effect of CP on testes' weight and volume, DSP, ESP, testosterone production, TAS, TOS, and OSI. Histoarchitectecture showing normal seminiferous tubules and even distribution of glycogen and collagen fibers.

CONCLUSION

Treatment with SFN ameliorate CP-induced testicular toxicity by reversing the cytotoxic mechanisms of CP.

Assessment of Methodological Pipelines for the Determination of Isothiocyanates Derived from Natural Sources

Isothiocyanates are biologically active secondary metabolites liberated via enzymatic hydrolysis of their sulfur enriched precursors, glucosinolates, upon tissue plant disruption. The importance of this class of compounds lies in their capacity to induce anti-cancer, anti-microbial, anti-inflammatory, neuroprotective, and other bioactive properties. As such, their isolation from natural sources is of utmost importance. In this review article, an extensive examination of the various parameters (hydrolysis, extraction, and quantification) affecting the isolation of isothiocyanates from naturally-derived sources is presented. Overall, the effective isolation/extraction and quantification of isothiocyanate is strongly associated with their chemical and physicochemical properties, such as polarity-solubility as well as thermal and acidic stability. Furthermore, the successful activation of myrosinase appears to be a major factor affecting the conversion of glucosinolates into active isothiocyanates.

Bacterial-Assisted Extraction of Bioactive Compounds from Cauliflower

The market for nutraceutical molecules is growing at an impressive pace in all Western countries. A convenient source of bioactive compounds is found in vegetable waste products, and their re-use for the recovery of healthy biomolecules would increase the sustainability of the food production system. However, safe, cheap, and sustainable technologies should be applied for the recovery of these beneficial molecules, avoiding the use of toxic organic solvents or expensive equipment. The soil bacterium Bacillus subtilis is naturally endowed with several enzymes targeting complex vegetable polymers. In this work, a raw bacterial culture supernatant was used to assist in the extraction of bioactives using isothermal pressurization cycles. Besides a wild-type Bacillus subtilis strain, a new strain showing increased secretion of cellulases and xylanases, pivotal enzymes for the digestion of the plant cell wall, was also used. Results indicate that the recovery of compounds correlates with the amount of cellulolytic enzymes applied, demonstrating that the pretreatment with non-purified culture broth effectively promotes the release of bioactives from the vegetable matrix. Therefore, this approach is a valid and sustainable procedure for the recovery of bioactive compounds from food waste.