Chronic ethanol intake inhibits in vitro osteogenesis induced by osteoblasts differentiated from stem cells

Abstract

The study investigated whether chronic ethanol (ETH) intake and subsequent ETH exposure of cell cultures affects osteoblast differentiation by evaluating key parameters of in vitro osteogenesis. Rats were treated with 5-20% (0.85-3.43 mm) ETH, increasing by 5% per week for a period of 4 weeks (habituation), after which the 20% level was maintained for 15 days (chronic intake). Bone-marrow stem cells from control (CONT) or ETH-treated rats were cultured in osteogenic medium which was either supplemented (ETH) or not supplemented (CONT) with 1.3 mm ethanol. Thus, four groups relating to rat treatment/culture supplementation were evaluated: (1) CONT/CONT, (2) ETH/CONT, (3) CONT/ETH and (4) ETH/ETH. Cell morphology, proliferation and viability, total protein content, alkaline phosphatase (ALP) activity and bone-like nodule formation were evaluated. Chronic ethanol intake significantly reduced both food and liquid consumption and body weight gain. No difference was seen in cell morphology among treatments. Cell number was affected at 7 and 10 days as follows: CONT/CONT = CONT/ETH < ETH/CONT = ETH/ETH. Doubling time between 3 and 10 days was greater in groups of CONT animals: ETH/ETH = ETH/CONT < CONT/ETH = CONT/CONT. Cell viability and ALP activity were not affected by either animal treatment or culture exposure to ethanol. At day 21, the total protein content was affected as follows: ETH/ETH = CONT/ETH < ETH/CONT = CONT/CONT. Bone-like nodule formation was affected as follows: ETH/ETH < CONT/ETH < ETH/CONT < CONT/CONT. These results show that chronic ethanol intake, followed by the exposure of osteoblasts to ethanol, inhibited the differentiation of osteoblasts, as indicated by an increased proliferation rate and reduced bone-like nodule formation.

Alcohol and bone: review of dose effects and mechanisms

“…Despite the fact that the doses used by Cui et al are lethal for humans (Table 2), an inverse relationship between osteogenesis and adipogenesis has been observed in rat stromal cultures [101]. Gong and Wezeman observed that alcohol (50 mmol alcohol in the culture medium) alters osteogenic differentiation in human bone-marrow-derived mesenchymal stem cell (MSC) cultures during lineage progression [102] which was confirmed by Rosa et al with ethanol doses of between 0.85 and 3.43 mmol [103]. This result provides further insight into alcohol-induced reduced bone formation.…”

ER Stress Activating ATF4/CHOP-TNF-α Signaling Pathway Contributes to Alcohol-Induced Disruption of Osteogenic Lineage of Multipotential Mesenchymal Stem Cell

“…While it has long been known that excessive alcohol consumption promotes adipogenesis and inhibits osteogenesis [5,6,7,8,9] and induces ER stress [11,12,13] that mediates alcoholic damages to many organs, the relationship between ER stress and osteogenesis disruption in BMSCs remained unknown. The present study provides evidence for the role of ER stress in mediating osteogenesis disruption after chronic alcohol exposure.…”

“…Excessive alcohol consumption substantially promotes adipogenesis and inhibits osteogenesis [5,6,7,8,9]. Moreover, both chronic and binge consumptions of ethanol are known to cause suppression of bone formation and enhancement of bone resorption.…”

Detrimental Effects of Alcohol on Bone Growth

“…Alcohol consumption results in a dosedependent decrease in bone formation that is paralleled by reductions in osteoblast-lined bone surface and osteoblast precursor pool in bone marrow (Dyer et al 1998;Rosa et al 2008). Reduced bone formation is preceded by lower mRNA levels for bone matrix proteins ).…”