Theobromine Upregulates Osteogenesis by Human Mesenchymal Stem Cells In Vitro and Accelerates Bone Development in Rats.

Theobromine (THB) is one of the major xanthine-like alkaloids found in cacao plant and a variety of other foodstuffs such as tea leaves, guarana and cola nuts. Historically, THB and its derivatives have been utilized to treat cardiac and circulatory disorders, drug-induced nephrotoxicity, proteinuria and as an immune-modulator. Our previous work demonstrated that THB has the capacity to improve the formation of hydroxyl-apatite during tooth development, suggesting that it may also enhance skeletal development. With its excellent safety profile and resistance to pharmacokinetic elimination, we reasoned that it might be an excellent natural osteoanabolic supplement during pregnancy, lactation and early postnatal growth. To determine whether THB had an effect on human osteoprogenitors, we subjected primary human bone marrow mesenchymal stem cells (hMSCs) to osteogenic assays after exposure to THB in vitro and observed that THB exposure increased the rate of osteogenesis and mineralization by hMSCs. Moreover, THB exposure resulted in a list of upregulated mRNA transcripts that best matched an osteogenic tissue expression signature as compared to other tissue expression signatures archived in several databases. To determine whether oral administration of THB resulted in improved skeletal growth, we provided pregnant rats with chow supplemented with THB during pregnancy and lactation. After weaning, offspring received THB continuously until postnatal day 50 (approximately 10 mg kg-1 day-1). Administration of THB resulted in neonates with larger bones, and 50-day-old offspring accumulated greater body mass, longer and thicker femora and superior tibial trabecular parameters. The accelerated growth did not adversely affect the strength and resilience of the bones. These results indicate that THB increases the osteogenic potential of bone marrow osteoprogenitors, and dietary supplementation of a safe dose of THB to expectant mothers and during the postnatal period could accelerate skeletal development in their offspring.

Adverse effects of incorporating ketoprofen into established rodent studies.

The use of analgesics to prevent or treat postprocedural pain in rodents is increasingly encouraged by the laboratory animal community and federal funding agencies. However, the effects of analgesics on experimental outcomes are not well-documented. In this study, we incorporated ketoprofen into a well-established experimental protocol. Of the 44 Sprague-Dawley (SD) rats obtained from vendor A that were given either ketoprofen (10 mg/kg s.c.) or saline and underwent ovariectomy, 19 that received ketoprofen died or were euthanized due to clinical illness within 3 to 7 d after surgery. Necropsy revealed gastrointestinal ulceration consistent with toxicity from nonsteroidal antiinflammatory drug. In an attempt to identify factors responsible for this unanticipated outcome, SD rats from vendors A and B were subjected to the same protocol, but no clinical signs or pathologic lesions were observed in any of these rats, regardless of source. A third experiment with rats obtained from vendor A and housed in barriers 1 and 2 was done to clarify the conflicting results and to determine whether response to ketoprofen differed at the barrier level. Three of the 6 rats from barrier 2 that received ketoprofen in the third study had gastrointestinal lesions similar to those observed in the fi rst study, whereas none of the rats from barrier 1 had any lesions. These results suggest that the adverse effects seen after administration of ketoprofen were due to differences between barriers.