Functions and mechanisms of green tea catechins in regulating bone remodeling.

Osteoporosis is caused by an imbalance in bone remodeling, a process involving bone-building osteoblasts and bone-resorptive osteoclasts. Excessive reactive oxygen species and inflammatory responses have been shown to stimulate differentiation and function of osteoclasts while inducing osteoblast apoptosis and suppressing osteoblastic proliferation and differentiation via extracellular signal-regulated kinases (ERK), ERK-dependent nuclear factor-κB and Wnt/ß-catenin signaling pathways. The anti-oxidant and anti-inflammatory green tea catechins (GTC) have been shown to promote osteoblastogenesis, suppress osteoclastogenesis and stimulate the differentiation of mesenchymal stem cells into osteoblasts rather than adipocytes by modulating the signaling pathways. This paper reviews the pharmacokinetics and metabolism of GTC, their bone-protective activities evidenced in in vitro and in vivo studies, and the limited clinical studies supporting these preclinical findings. In light of the physical, economical, and social burdens due to osteoporosis, easily accessible and affordable preventive measures such as GTC deserves further clinical studies prior to its clinical application.

Bioactive compounds and phenolic-linked functionality of powdered tropical fruit residues.

Tropical fruit residues consisting of seeds, peels and residual pulp generated as by-products of fruit processing industry were investigated for bioactive compounds, the in vitro antioxidant capacity as well as alpha-glucosidase and alpha-amylase inhibitory activities. Cyanidin, quercetin, ellagic acid (EA) and proanthocyanidins were found in acerola, jambolan, pitanga and cajá-umbu residue powders. Acerola powder had the highest phenolic content (8839.33 mg catechin equivalents (CE)/100 g) and also high-ascorbic acid (AA) concentration (2748.03 mg/100 g), followed by jambolan and pitanga. The greatest 1,1-Diphenyl-2-picrylhydrazyl (DPPH) inhibition was observed for jambolan (436.76 mmol Trolox eq/g) followed by pitanga (206.68 mmol Trolox eq/g) and acerola (192.60 mmol Trolox eq/g), while acerola had the highest ferric reducing antioxidant power (FRAP) assay result (7.87 mmol Trolox eq/g). All fruit powders exhibited enzymatic inhibition against alpha-amylase (IC50 ranging from 3.40 to 49.5 mg CE/mL) and alpha-glucosidase (IC50 ranging from 1.15 to 2.37 mg CE/mL). Therefore, acerola, jambolan and pitanga dried residues are promising natural ingredients for food and nutraceutical manufacturers, due to their rich bioactive compound content.

A cost-effectiveness analysis of sinecatechins in the treatment of external genital warts.

OBJECTIVE: To evaluate the cost-effectiveness and treatment-cost impact of sinecatechins (Veregen) as first-line therapy against its principal comparator, imiquimod (Aldara), in the treatment of external genital warts (EGWs). METHOD: A two-stage decision model is proposed to compare sinecatechins with its principal comparator, imiquimod, as a first-line topical therapy in the treatment of EGWs. The model utilizes estimates of sustained clearance from two pivotal sinecatechins trials and from a systematic literature review for imiquimod. Resource inputs are: (1) trial-based estimates of average drug utilization and (2) CPT (Current Procedural Terminology) codes describing anticipated office visits and utilization of second-line ablative procedures. The analysis considers: (1) comparative costs of achieving a successful outcome with sinecatechins versus imiquimod, and (2) comparative cost-consequences of sinecatechins versus imiquimod. As a modeled approach to evaluating comparative product effectiveness, the claims made reflect the structure of the model, which focuses on topical products as first-line therapy in EGW interventions and in its reliance on estimates of sustained clearance from pivotal randomized clinical trials (RCTs). Sustained clearance in this context being defined as the proportion of patients who report initial wart clearance over the RCT period corrected for subsequent recurrence. RESULTS: As first-line therapy, sinecatechins dominates imiquimod as a lower cost treatment with a higher sustained clearance rate (51.9 vs. 40.6%). First-line average cost of treatment with sinecatechins is $774 compared to imiquimod at $930. Cost per successful outcome with sinecatechins is $1,492, which is lower than $2,289 for imiquimod. Taking account of patients failing first-line therapy moving to a second-line ablative therapy yields an average cost of treatment for patients initiated to sinecatechins of $943 and $1,138 for those initiated to imiquimod. A sensitivity assessment confirmed the position of sinecatechins within the decision-model framework. CONCLUSION: Sinecatechins yields a lower cost of treatment compared to imiquimod in the treatment of EGW. It also offers cost savings to healthcare systems. This conclusion should be qualified by the limitations of the decision framework within which the assessment has been made. The model focuses on topical preparations as first-line therapies, with estimates of sustained clearance taken from pivotal RCTs. Treatment cost estimates are generated independently, but reflect current product and ancillary costs.