Bone-remodeling imbalance induced by increased bone resorption and osteoclast formation is known to cause skeletal diseases such as osteoporosis. There has been growing interest in the anabolic natural agents that enhance bone formation. Silymarin is flavonolignans extracted from blessed milk thistle. Several studies suggest that silymarin possesses antihepatotoxic properties and anticancer effects against carcinoma cells. This study investigated promoting effects of silymarin on differentiation and mineralization of osteoblastic MC3T3-E1 mouse cells and on bone mineral density (BMD) by in vivo fracture experiments. Osteoblasts were treated with 1–20 μmol/L silymarin for 15 days in a differentiating medium. In addition, this study explored signaling pathways implicated in the osteoblastogenesis of silymarin. It was found that silymarin stimulated alkaline phosphatase (ALP) activity and calcium nodule formation in a dose-dependent manner with a substantial effect on osteoblast proliferation. Silymarin treatment enhanced collagen secretion, osteocalcin transcription and bone morphogenetic protein (BMP) expression. The BMP inhibitor noggin suppressed the silymarin-promoted ALP activity in differentiated osteoblasts, suggesting that its osteoblastogenic actions entail the BMP pathway. This was proved by increased SMAD1/5/8 phosphorylation and runt-related transcription factor 2 (Runx2) expression in the presence of silymarin. In 21-day fracture-healing experiments, fractured and silymarin (10 mg/kg)-treated C57BL/6 mice showed better bone healing than fractured mice. Silymarin supplementation improved tibial bone strength with elevated BMD and serum levels of osteogenic ALP and osteocalcin. Taken together, these results demonstrate, for the first time, that silymarin has a potential to enhance osteoblastogenesis through accelerating BMP/SMAD/Runx2 signal pathways and to improve fracture healing and bone strength in mouse tibiae.
Few studies have summarized the association between dietary factors and breast cancer (BC) prognosis among breast cancer survivors (BCS). Therefore, we carried out a systematic review and meta-analysis to determine the associations between dietary factors and BC prognosis among BCS. We performed a literature search in PubMed and Embase to investigate the association between dietary factors and BC prognosis. We applied a random-effects model to compute the hazard ratio/relative risk and their 95% confidence intervals and heterogeneity (Higgins I2) and to generate forest plots using STATA. Among the 2279 papers identified, 63 cohort studies were included in the systematic review and meta-analysis. Our main finding was that higher consumption of beer and saturated fat negatively affected BC prognosis. However, the intake of lignans, fiber, multivitamins, and antioxidants was negatively associated with the risk of mortality. Furthermore, we performed subgroup analyses by menopausal status and dietary or supplementary micronutrient intake. Most trends were similar to the main findings; in particular, the vitamin C, vitamin D, and vitamin E supplements decreased the risk of mortality. This study’s current systematic review and meta-analysis provide comprehensive dietary information for the development of dietary guidelines/recommendations to improve prognosis among BCS.
Osteosarcoma is a common and aggressive bone cancer in children and adolescents, typically affecting the long bones during growth spurts. Treatment involves a combination of surgery, chemotherapy, and radiotherapy. Although surgery has become more limb-preserving, the overall prognosis remains challenging, with a 5-year survival rate of 60-70% for localized disease and much lower for advanced stages. Chemotherapy is the mainstay treatment; however, it can cause severe side effects. Targeted therapies (e.g., IGF-1R inhibitors, TKIs) and immunotherapy (e.g., checkpoint inhibitors, CAR-T therapies) are promising areas of research that aim to attack cancer cells more precisely with lower toxicity. Other novel approaches, such as gene therapy and drug delivery systems, are being explored. With continued research and development of new therapies, we hope to significantly improve the outlook of patients with osteosarcoma in the future.
Degenerative tendinopathy results from the accumulation of minor injuries following unsuccessful tendon repair during acute tendon injuries. The process of tendon repair is prolonged and varies between individuals, making it susceptible to reinjury. Moreover, treating chronic tendinopathy often requires expensive and extensive rehabilitation, along with a variety of combined therapies to facilitate recovery. This condition significantly affects the quality of life of affected individuals, underscoring the urgent need for more efficient and cost-effective treatment options. Although traditional treatments have improved significantly and are being used as substitutes for surgical interventions, the findings have been inconsistent and conflicting. This review aims to clarify these issues by exploring the strengths and limitations of current treatments as well as recent innovations in managing various forms of degenerative tendinopathy.
The imbalance between bone resorption and bone formation in favor of resorption results in bone loss and deterioration of bone architecture. Osteoblast differentiation is a sequential event accompanying biogenesis of matrix vesicles and mineralization of collagen matrix with hydroxyapatite crystals. Considerable efforts have been made in developing naturally-occurring plant compounds, preventing bone pathologies, or enhancing bone regeneration. Coumarin aesculetin inhibits osteoporosis through hampering the ruffled border formation of mature osteoclasts. However, little is known regarding the effects of aesculetin on the impairment of matrix vesicle biogenesis. MC3T3-E1 cells were cultured in differentiation media with 1–10 μM aesculetin for up to 21 days. Aesculetin boosted the bone morphogenetic protein-2 expression, and alkaline phosphatase activation of differentiating MC3T3-E1 cells. The presence of aesculetin strengthened the expression of collagen type 1 and osteoprotegerin and transcription of Runt-related transcription factor 2 in differentiating osteoblasts for 9 days. When ≥1–5 μM aesculetin was added to differentiating cells for 15–18 days, the induction of non-collagenous proteins of bone sialoprotein II, osteopontin, osteocalcin, and osteonectin was markedly enhanced, facilitating the formation of hydroxyapatite crystals and mineralized collagen matrix. The induction of annexin V and PHOSPHO 1 was further augmented in ≥5 μM aesculetin-treated differentiating osteoblasts for 21 days. In addition, the levels of tissue-nonspecific alkaline phosphatase and collagen type 1 were further enhanced within the extracellular space and on matrix vesicles of mature osteoblasts treated with aesculetin, indicating matrix vesicle-mediated bone mineralization. Finally, aesculetin markedly accelerated the production of thrombospondin-1 and tenascin C in mature osteoblasts, leading to their adhesion to preformed collagen matrix. Therefore, aesculetin enhanced osteoblast differentiation, and matrix vesicle biogenesis and mineralization. These findings suggest that aesculetin may be a potential osteo-inductive agent preventing bone pathologies or enhancing bone regeneration.
Osteoporosis is evident in postmenopausal women and is an osteolytic disease characterized by bone loss that further increases the susceptibility to bone fractures and frailty. The use of complementary therapies to alleviate postmenopausal osteoporosis is fairly widespread among women. Edible Cirsium setidens contains various polyphenols of linarin, pectolinarin, and apigenin with antioxidant and hepatoprotective effects. This study aimed to determine whether Cirsium setidens water extracts (CSEs), the component linarin, and its aglycone acacetin blocked ovariectomy (OVX)-induced bone loss. This study employed OVX C57BL/6 female mice as a model for postmenopausal osteoporosis. CSEs, acacetin, or linarin was orally administrated to OVX mice at a dose of 20 mg/kg for 8 weeks. Surgical estrogen loss in mice for 8 weeks reduced bone mineral density (BMD) of mouse femur and serum 17β-estradiol level and enhanced the serum receptor activator of NF-κB ligand/osteoprotegerin ratio with uterine atrophy. CSEs and linarin reversed such adverse effects and enhanced femoral BMD in OVX mice. Oral administration of CSEs and linarin attenuated tartrate-resistant acid phosphate activity and the induction of αvβ3 integrins and proton suppliers in resorption lacunae in femoral bone tissue of OVX mice. In addition, CSEs and linarin curtailed the bone levels of cathepsin K and matrix metalloproteinase-9 responsible for osteoclastic bone resorption. On the other hand, CSEs and linarin enhanced the formation of trabecular bones in estrogen-deficient femur with increased induction of osteocalcin and osteopontin. Further, treatment with CSEs and linarin enhanced the collagen formation-responsive propeptide levels in the circulation along with the increase in the tissue non-specific alkaline phosphatase level in bone exposed to OVX. Supplementing CSEs, acacetin, or linarin to OVX mice elevated the formation of collagen fibers in OVX trabecular bone, evidenced using Picrosirius red staining. Accordingly, CSEs and linarin were effective in retarding osteoclastic bone resorption and promoting osteoblastic bone matrix mineralization under OVX conditions. Therefore, linarin, which is abundant in CSEs, may be a natural compound for targeting postmenopausal osteoporosis and pathological osteoresorptive disorders.