Short time administration of antirheumatic drugs - Methotrexate as a strong inhibitor of osteoblast's proliferation in vitro

Abstract

IntroductionDue to increasing use of disease modifying antirheumatic drugs (DMARDs) as first line therapy in rheumatic diseases, dental and maxillofacial practitioner should be aware of drug related adverse events. Especially effects on bone-metabolism and its cells are discussed controversially. Therefore we investigate the in vitro effect of short time administration of low dose methotrexate (MTX) on osteoblasts as essential part of bone remodelling cells.MethodsPrimary bovine osteoblasts (OBs) were incubated with various concentrations of MTX, related to tissue concentrations, over a period of fourteen days by using a previously established standard protocol. The effect on cell proliferation as well as mitochondrial activity was assessed by using 3-(4, 5-dimethylthiazol-2-yl) 2, 5-diphenyltetrazolium bromide (MTT) assay, imaging and counting of living cells. Additionally, immunostaining of extracellular matrix proteins was used to survey osteogenic differentiation.ResultsAll methods indicate a strong inhibition of osteoblast`s proliferation by short time administration of low dose MTX within therapeutically relevant concentrations of 1 to 1000nM, without affecting cell differentiation of middle-stage differentiated OBs in general. More over a significant decrease of cell numbers and mitochondrial activity was found at these MTX concentrations. The most sensitive method seems to be the MTT-assay. MTX-concentration of 0,01nM and concentrations below had no inhibitory effects anymore.ConclusionEven low dose methotrexate acts as a potent inhibitor of osteoblast’s proliferation and mitochondrial metabolism in vitro, without affecting main differentiation of pre-differentiated osteoblasts. These results suggest possible negative effects of DMARDs concerning bone healing and for example osseointegration of dental implants. Especially the specifics of the jaw bone with its high vascularisation and physiological high tissue metabolism, suggests possible negative effects of DMARD therapy concerning oral and cranio-maxillofacial bone surgery as could be seen in a similar way in bisphosphonate related osteonecrosis of the jaw.

Dental implants in patients with Sjögren’s syndrome: a case series and a systematic review

“…42 Besides corticosteroids, methotrexate 43 and biological-targeted therapies, including TNF-α inhibitors and rituximab, 44 have been used in patients with primary SS-associated inflammatory arthritis. Methotrexate has been shown to be a potent inhibitor of osteoblast's proliferation and mitochondrial metabolism in vitro, 45 and to have the potential to interfere with the osseointegration process. 46 Concerning biological 13 agents, these have been found to have effects on human chondrocytes and osteocytes in vitro, 47 and to present a significant suppression in bone turnover.…”

Менеджмент Пацієнтів З Ревматоїдним Артритом У Періопераційному Періоді

“…It should be noted that recommendations as to starting and ceasing the drug use during surgery is forever changing. For instance, in the past it was recommended to suspend the methotrexate use 2 weeks before surgery and resume it 2 weeks afterwards to avoid inflammatory process [25][26][27]. The same recommendation concerned Leflunomide [28].…”

“…The reference sources contain controversial opinions on whether the Methotrexate (MTX) causes the osteoblast inhibition. In light of this controversy, some sources still recommend ceasing Methotrexate Bol', sustavy, pozvonočnik, ISSN 2224-1507 (print), ISSN 2307-1133 (online) Практична медицина / Practical Medicine (MTX) 1 week before the surgery and resume it 1-2 weeks afterwards [25][26][27].…”

Dental Implants in the Medically Compromised Patient Population

“…In animal studies, it is showed that immunosuppressive drugs reduce osteoblast's proliferation and impair implant osseointegration [79,80]. Furthermore, immunocompromised condition may present additional risks for blood borne infections [28].…”