The effect and mechanism of YH0618 granule on chemotherapy- induced hair loss in patients with breast cancer: study protocol for a randomized, double-blind, multi-center clinical trial.

BACKGROUND: Hair loss is one of the most common side effects of chemotherapy, and can cause persistent negative emotions, further affecting therapeutic effects and reducing the quality of life. However, there are no clinically safe and effective methods to solve the problem at present. Our previous clinical and animal studies showed that a medicinal and edible decoction, YH0618, could significantly promote hair growth in cancer patients after chemotherapy, without interfering with the anti-tumor effects of chemotherapy. Besides, the theory of Chinese Medicine believes that the "Essence of the kidney is reflected on the hair". Therefore, this study will further explore the efficacy of YH0618 granule on chemotherapy-induced hair loss in patients with breast cancer by a randomized, double-blind, multi-center clinical trial and elucidate the potential mechanism from the aspect of kidney deficiency or renal dysfunction. METHODS/DESIGN: Eligible breast cancer patients who will start chemotherapy will be randomly divided into group A (YH0618 granule) and group B (placebo). The chemotherapeutic agents contain taxanes or/and anthracyclines, and the chemotherapy regimen will be for at least six cycles with a cycle every 3 weeks. Subjects assigned to group A will receive YH0618 granules twice a day (6 g each time), 6 days a week, mixed with 300 ml warm water from the first to the fourth chemotherapy cycle. Subjects in group B will receive the placebo granule in the same manner. The primary outcome is the time point of occurrence of hair loss reaching grade II as assessed by the WHO Toxicity Grading Scale, and objective indices of hair quality and hair-follicle growth recorded by a hair and scalp detector before the fifth chemotherapy cycle. Secondary outcomes include changes of facial color and thumbnail color, grading of thumbnails ridging, assessment of quality life, level of fatigue, routine blood test results, hepatic and renal function, and certain medical indicators which can reflect kidney deficiency in Chinese Medicine. DISCUSSION: This research is of great significance for the treatment of cancer and improving the quality of life of cancer patients. The study may provide the most direct evidence for meeting clinical needs and lay a solid scientific foundation for later product development. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ID: ChiCTR1800020107. Registered on 14 December 2018.

Characterization of Thermostable and Chimeric Enzymes via Isopeptide Bond-Mediated Molecular Cyclization.

Mannooligosaccharides are released by mannan-degrading endo-ß-1,4-mannanase and are known as functional additives in human and animal diets. To satisfy demands for biocatalysis and bioprocessing in crowed environments, in this study, we employed a recently developed enzyme-engineering system, isopeptide bond-mediated molecular cyclization, to modify a mesophilic mannanase from Bacillus subtilis. The results revealed that the cyclized enzymes showed enhanced thermostability and ion stability and resilience to aggregation and freeze-thaw treatment by maintaining their conformational structures. Additionally, by using the SpyTag/SpyCatcher system, we generated a mannanase-xylanase bifunctional enzyme that exhibited a synergistic activity in substrate deconstruction without compromising substrate affinity. Interestingly, the dual-enzyme ring conformation was observed to be more robust than the linear enzyme but inferior to the single-enzyme ring conformation. Taken together, these findings provided new insights into the mechanisms of molecular cyclization on stability improvement and will be useful in the production of new functional oligosaccharides and feed additives.

Inhibitory effect of phloroglucinol on α-glucosidase: Kinetics and molecular dynamics simulation integration study.

Regulation of α-glucosidase (EC 3.2.1.20) and its inhibitors is of great interest to researchers due to its clinical relevance as a target enzyme for the treatment of α-glucosidase-mediated diseases, such as type 2 diabetes mellitus and Pompe disease. In this study, we conducted a phloroglucinol-induced inhibition kinetics assay and performed computational molecular dynamics (MD) simulations to assess binding manner in α-glucosidase. The results showed that phloroglucinol reversibly inhibited α-glucosidase in a dose-dependent but non-competitive manner (Ki=2.07±0.16mM). Interestingly, the maximum peak wavelength and the hydrophobic surface remained unchanged during the inhibition reaction, with computational MD simulations further revealing that phloroglucinol bound in front of the active site pocket rather than in the α-glucosidase active site. Therefore, we speculate that phloroglucinol-specific inhibition is mild and the inhibitor likely binds to a single binding site near but not in the active site. Our study provided insight into the effects and mechanisms associated with a mild inhibitor of α-glucosidase activity and promotes fundamental research and potential applications of inhibitors for treatment of α-glucosidase-mediated clinical disease.